-- #################################################################################################
|
-- #################################################################################################
|
-- # << NEORV32 - CPU Operations Control Unit >> #
|
-- # << NEORV32 - CPU Operations Control Unit >> #
|
-- # ********************************************************************************************* #
|
-- # ********************************************************************************************* #
|
-- # CPU operations are controlled by several "engines" (modules). These engines operate in #
|
-- # CPU operations are controlled by several "engines" (modules). These engines operate in #
|
-- # parallel to implement a simple pipeline: #
|
-- # parallel to implement a simple pipeline: #
|
-- # + Fetch engine: Fetches 32-bit chunks of instruction words #
|
-- # + Fetch engine: Fetches 32-bit chunks of instruction words #
|
-- # + Issue engine: Decodes compressed instructions, aligns and queues instruction words #
|
-- # + Issue engine: Decodes compressed instructions, aligns and queues instruction words #
|
-- # + Execute engine: Multi-cycle execution of instructions (generate control signals) #
|
-- # + Execute engine: Multi-cycle execution of instructions (generate control signals) #
|
-- # + Trap engine: Handles interrupts and exceptions #
|
-- # + Trap engine: Handles interrupts and exceptions #
|
-- # + CSR module: Read/write access to control and status registers #
|
-- # + CSR module: Read/write access to control and status registers #
|
-- # + Debug module: CPU debug mode handling (on-chip debugger) #
|
-- # + Debug module: CPU debug mode handling (on-chip debugger) #
|
-- # + Trigger module: Hardware-assisted breakpoints (on-chip debugger) #
|
-- # + Trigger module: Hardware-assisted breakpoints (on-chip debugger) #
|
-- # #
|
-- # #
|
-- # NOTE: If <dedicated_reset_c> = true then <def_rst_val_c> evaluates to '-'. Registers that #
|
-- # NOTE: If <dedicated_reset_c> = true then <def_rst_val_c> evaluates to '-'. Registers that #
|
-- # reset to <def_rst_val_c> do NOT actually have a real reset by default and have to be #
|
-- # reset to <def_rst_val_c> do NOT actually have a real reset by default and have to be #
|
-- # explicitly initialized by software! This is only used for "uncritical" registers. Many #
|
-- # explicitly initialized by software! This is only used for "uncritical" registers. Many #
|
-- # of them will be initialized by the default crt0 start-up code. #
|
-- # of them will be initialized by the default crt0 start-up code. #
|
-- # ********************************************************************************************* #
|
-- # ********************************************************************************************* #
|
-- # BSD 3-Clause License #
|
-- # BSD 3-Clause License #
|
-- # #
|
-- # #
|
-- # Copyright (c) 2022, Stephan Nolting. All rights reserved. #
|
-- # Copyright (c) 2022, Stephan Nolting. All rights reserved. #
|
-- # #
|
-- # #
|
-- # Redistribution and use in source and binary forms, with or without modification, are #
|
-- # Redistribution and use in source and binary forms, with or without modification, are #
|
-- # permitted provided that the following conditions are met: #
|
-- # permitted provided that the following conditions are met: #
|
-- # #
|
-- # #
|
-- # 1. Redistributions of source code must retain the above copyright notice, this list of #
|
-- # 1. Redistributions of source code must retain the above copyright notice, this list of #
|
-- # conditions and the following disclaimer. #
|
-- # conditions and the following disclaimer. #
|
-- # #
|
-- # #
|
-- # 2. Redistributions in binary form must reproduce the above copyright notice, this list of #
|
-- # 2. Redistributions in binary form must reproduce the above copyright notice, this list of #
|
-- # conditions and the following disclaimer in the documentation and/or other materials #
|
-- # conditions and the following disclaimer in the documentation and/or other materials #
|
-- # provided with the distribution. #
|
-- # provided with the distribution. #
|
-- # #
|
-- # #
|
-- # 3. Neither the name of the copyright holder nor the names of its contributors may be used to #
|
-- # 3. Neither the name of the copyright holder nor the names of its contributors may be used to #
|
-- # endorse or promote products derived from this software without specific prior written #
|
-- # endorse or promote products derived from this software without specific prior written #
|
-- # permission. #
|
-- # permission. #
|
-- # #
|
-- # #
|
-- # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS #
|
-- # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS #
|
-- # OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF #
|
-- # OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF #
|
-- # MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE #
|
-- # MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE #
|
-- # COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, #
|
-- # COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, #
|
-- # EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE #
|
-- # EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE #
|
-- # GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED #
|
-- # GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED #
|
-- # AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING #
|
-- # AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING #
|
-- # NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED #
|
-- # NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED #
|
-- # OF THE POSSIBILITY OF SUCH DAMAGE. #
|
-- # OF THE POSSIBILITY OF SUCH DAMAGE. #
|
-- # ********************************************************************************************* #
|
-- # ********************************************************************************************* #
|
-- # The NEORV32 Processor - https://github.com/stnolting/neorv32 (c) Stephan Nolting #
|
-- # The NEORV32 Processor - https://github.com/stnolting/neorv32 (c) Stephan Nolting #
|
-- #################################################################################################
|
-- #################################################################################################
|
|
|
library ieee;
|
library ieee;
|
use ieee.std_logic_1164.all;
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use ieee.std_logic_1164.all;
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use ieee.numeric_std.all;
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use ieee.numeric_std.all;
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|
|
library neorv32;
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library neorv32;
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use neorv32.neorv32_package.all;
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use neorv32.neorv32_package.all;
|
|
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entity neorv32_cpu_control is
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entity neorv32_cpu_control is
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generic (
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generic (
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-- General --
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-- General --
|
HW_THREAD_ID : natural; -- hardware thread id (32-bit)
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HW_THREAD_ID : natural; -- hardware thread id (32-bit)
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CPU_BOOT_ADDR : std_ulogic_vector(31 downto 0); -- cpu boot address
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CPU_BOOT_ADDR : std_ulogic_vector(31 downto 0); -- cpu boot address
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CPU_DEBUG_ADDR : std_ulogic_vector(31 downto 0); -- cpu debug mode start address
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CPU_DEBUG_ADDR : std_ulogic_vector(31 downto 0); -- cpu debug mode start address
|
-- RISC-V CPU Extensions --
|
-- RISC-V CPU Extensions --
|
CPU_EXTENSION_RISCV_A : boolean; -- implement atomic extension?
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CPU_EXTENSION_RISCV_A : boolean; -- implement atomic extension?
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CPU_EXTENSION_RISCV_B : boolean; -- implement bit-manipulation extension?
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CPU_EXTENSION_RISCV_B : boolean; -- implement bit-manipulation extension?
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CPU_EXTENSION_RISCV_C : boolean; -- implement compressed extension?
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CPU_EXTENSION_RISCV_C : boolean; -- implement compressed extension?
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CPU_EXTENSION_RISCV_E : boolean; -- implement embedded RF extension?
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CPU_EXTENSION_RISCV_E : boolean; -- implement embedded RF extension?
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CPU_EXTENSION_RISCV_M : boolean; -- implement mul/div extension?
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CPU_EXTENSION_RISCV_M : boolean; -- implement mul/div extension?
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CPU_EXTENSION_RISCV_U : boolean; -- implement user mode extension?
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CPU_EXTENSION_RISCV_U : boolean; -- implement user mode extension?
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CPU_EXTENSION_RISCV_Zfinx : boolean; -- implement 32-bit floating-point extension (using INT reg!)
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CPU_EXTENSION_RISCV_Zfinx : boolean; -- implement 32-bit floating-point extension (using INT reg!)
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CPU_EXTENSION_RISCV_Zicsr : boolean; -- implement CSR system?
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CPU_EXTENSION_RISCV_Zicsr : boolean; -- implement CSR system?
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CPU_EXTENSION_RISCV_Zicntr : boolean; -- implement base counters?
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CPU_EXTENSION_RISCV_Zicntr : boolean; -- implement base counters?
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CPU_EXTENSION_RISCV_Zihpm : boolean; -- implement hardware performance monitors?
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CPU_EXTENSION_RISCV_Zihpm : boolean; -- implement hardware performance monitors?
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CPU_EXTENSION_RISCV_Zifencei : boolean; -- implement instruction stream sync.?
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CPU_EXTENSION_RISCV_Zifencei : boolean; -- implement instruction stream sync.?
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CPU_EXTENSION_RISCV_Zmmul : boolean; -- implement multiply-only M sub-extension?
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CPU_EXTENSION_RISCV_Zmmul : boolean; -- implement multiply-only M sub-extension?
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CPU_EXTENSION_RISCV_Zxcfu : boolean; -- implement custom (instr.) functions unit?
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CPU_EXTENSION_RISCV_Zxcfu : boolean; -- implement custom (instr.) functions unit?
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CPU_EXTENSION_RISCV_DEBUG : boolean; -- implement CPU debug mode?
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CPU_EXTENSION_RISCV_DEBUG : boolean; -- implement CPU debug mode?
|
-- Tuning Options --
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-- Tuning Options --
|
FAST_MUL_EN : boolean; -- use DSPs for M extension's multiplier
|
FAST_MUL_EN : boolean; -- use DSPs for M extension's multiplier
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FAST_SHIFT_EN : boolean; -- use barrel shifter for shift operations
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FAST_SHIFT_EN : boolean; -- use barrel shifter for shift operations
|
CPU_CNT_WIDTH : natural; -- total width of CPU cycle and instret counters (0..64)
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CPU_CNT_WIDTH : natural; -- total width of CPU cycle and instret counters (0..64)
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CPU_IPB_ENTRIES : natural; -- entries is instruction prefetch buffer, has to be a power of 2
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CPU_IPB_ENTRIES : natural; -- entries is instruction prefetch buffer, has to be a power of 2
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-- Physical memory protection (PMP) --
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-- Physical memory protection (PMP) --
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PMP_NUM_REGIONS : natural; -- number of regions (0..16)
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PMP_NUM_REGIONS : natural; -- number of regions (0..16)
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PMP_MIN_GRANULARITY : natural; -- minimal region granularity in bytes, has to be a power of 2, min 4 bytes
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PMP_MIN_GRANULARITY : natural; -- minimal region granularity in bytes, has to be a power of 2, min 4 bytes
|
-- Hardware Performance Monitors (HPM) --
|
-- Hardware Performance Monitors (HPM) --
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HPM_NUM_CNTS : natural; -- number of implemented HPM counters (0..29)
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HPM_NUM_CNTS : natural; -- number of implemented HPM counters (0..29)
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HPM_CNT_WIDTH : natural -- total size of HPM counters (0..64)
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HPM_CNT_WIDTH : natural -- total size of HPM counters (0..64)
|
);
|
);
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port (
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port (
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-- global control --
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-- global control --
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clk_i : in std_ulogic; -- global clock, rising edge
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clk_i : in std_ulogic; -- global clock, rising edge
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rstn_i : in std_ulogic; -- global reset, low-active, async
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rstn_i : in std_ulogic; -- global reset, low-active, async
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ctrl_o : out std_ulogic_vector(ctrl_width_c-1 downto 0); -- main control bus
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ctrl_o : out std_ulogic_vector(ctrl_width_c-1 downto 0); -- main control bus
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-- status input --
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-- status input --
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alu_idone_i : in std_ulogic; -- ALU iterative operation done
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alu_idone_i : in std_ulogic; -- ALU iterative operation done
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bus_i_wait_i : in std_ulogic; -- wait for bus
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bus_i_wait_i : in std_ulogic; -- wait for bus
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bus_d_wait_i : in std_ulogic; -- wait for bus
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bus_d_wait_i : in std_ulogic; -- wait for bus
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excl_state_i : in std_ulogic; -- atomic/exclusive access lock status
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excl_state_i : in std_ulogic; -- atomic/exclusive access lock status
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-- data input --
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-- data input --
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instr_i : in std_ulogic_vector(data_width_c-1 downto 0); -- instruction
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instr_i : in std_ulogic_vector(data_width_c-1 downto 0); -- instruction
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cmp_i : in std_ulogic_vector(1 downto 0); -- comparator status
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cmp_i : in std_ulogic_vector(1 downto 0); -- comparator status
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alu_add_i : in std_ulogic_vector(data_width_c-1 downto 0); -- ALU address result
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alu_add_i : in std_ulogic_vector(data_width_c-1 downto 0); -- ALU address result
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rs1_i : in std_ulogic_vector(data_width_c-1 downto 0); -- rf source 1
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rs1_i : in std_ulogic_vector(data_width_c-1 downto 0); -- rf source 1
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-- data output --
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-- data output --
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imm_o : out std_ulogic_vector(data_width_c-1 downto 0); -- immediate
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imm_o : out std_ulogic_vector(data_width_c-1 downto 0); -- immediate
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fetch_pc_o : out std_ulogic_vector(data_width_c-1 downto 0); -- PC for instruction fetch
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fetch_pc_o : out std_ulogic_vector(data_width_c-1 downto 0); -- PC for instruction fetch
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curr_pc_o : out std_ulogic_vector(data_width_c-1 downto 0); -- current PC (corresponding to current instruction)
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curr_pc_o : out std_ulogic_vector(data_width_c-1 downto 0); -- current PC (corresponding to current instruction)
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next_pc_o : out std_ulogic_vector(data_width_c-1 downto 0); -- next PC (corresponding to next instruction)
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next_pc_o : out std_ulogic_vector(data_width_c-1 downto 0); -- next PC (corresponding to next instruction)
|
csr_rdata_o : out std_ulogic_vector(data_width_c-1 downto 0); -- CSR read data
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csr_rdata_o : out std_ulogic_vector(data_width_c-1 downto 0); -- CSR read data
|
-- FPU interface --
|
-- FPU interface --
|
fpu_flags_i : in std_ulogic_vector(04 downto 0); -- exception flags
|
fpu_flags_i : in std_ulogic_vector(04 downto 0); -- exception flags
|
-- debug mode (halt) request --
|
-- debug mode (halt) request --
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db_halt_req_i : in std_ulogic;
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db_halt_req_i : in std_ulogic;
|
-- interrupts (risc-v compliant) --
|
-- interrupts (risc-v compliant) --
|
msw_irq_i : in std_ulogic; -- machine software interrupt
|
msw_irq_i : in std_ulogic; -- machine software interrupt
|
mext_irq_i : in std_ulogic; -- machine external interrupt
|
mext_irq_i : in std_ulogic; -- machine external interrupt
|
mtime_irq_i : in std_ulogic; -- machine timer interrupt
|
mtime_irq_i : in std_ulogic; -- machine timer interrupt
|
-- fast interrupts (custom) --
|
-- fast interrupts (custom) --
|
firq_i : in std_ulogic_vector(15 downto 0);
|
firq_i : in std_ulogic_vector(15 downto 0);
|
-- system time input from MTIME --
|
-- system time input from MTIME --
|
time_i : in std_ulogic_vector(63 downto 0); -- current system time
|
time_i : in std_ulogic_vector(63 downto 0); -- current system time
|
-- physical memory protection --
|
-- physical memory protection --
|
pmp_addr_o : out pmp_addr_if_t; -- addresses
|
pmp_addr_o : out pmp_addr_if_t; -- addresses
|
pmp_ctrl_o : out pmp_ctrl_if_t; -- configs
|
pmp_ctrl_o : out pmp_ctrl_if_t; -- configs
|
-- bus access exceptions --
|
-- bus access exceptions --
|
mar_i : in std_ulogic_vector(data_width_c-1 downto 0); -- memory address register
|
mar_i : in std_ulogic_vector(data_width_c-1 downto 0); -- memory address register
|
ma_instr_i : in std_ulogic; -- misaligned instruction address
|
ma_instr_i : in std_ulogic; -- misaligned instruction address
|
ma_load_i : in std_ulogic; -- misaligned load data address
|
ma_load_i : in std_ulogic; -- misaligned load data address
|
ma_store_i : in std_ulogic; -- misaligned store data address
|
ma_store_i : in std_ulogic; -- misaligned store data address
|
be_instr_i : in std_ulogic; -- bus error on instruction access
|
be_instr_i : in std_ulogic; -- bus error on instruction access
|
be_load_i : in std_ulogic; -- bus error on load data access
|
be_load_i : in std_ulogic; -- bus error on load data access
|
be_store_i : in std_ulogic -- bus error on store data access
|
be_store_i : in std_ulogic -- bus error on store data access
|
);
|
);
|
end neorv32_cpu_control;
|
end neorv32_cpu_control;
|
|
|
architecture neorv32_cpu_control_rtl of neorv32_cpu_control is
|
architecture neorv32_cpu_control_rtl of neorv32_cpu_control is
|
|
|
-- CPU core counter ([m]cycle, [m]instret) width - high/low parts --
|
-- CPU core counter ([m]cycle, [m]instret) width - high/low parts --
|
constant cpu_cnt_lo_width_c : natural := natural(cond_sel_int_f(boolean(CPU_CNT_WIDTH < 32), CPU_CNT_WIDTH, 32));
|
constant cpu_cnt_lo_width_c : natural := natural(cond_sel_int_f(boolean(CPU_CNT_WIDTH < 32), CPU_CNT_WIDTH, 32));
|
constant cpu_cnt_hi_width_c : natural := natural(cond_sel_int_f(boolean(CPU_CNT_WIDTH > 32), CPU_CNT_WIDTH-32, 0));
|
constant cpu_cnt_hi_width_c : natural := natural(cond_sel_int_f(boolean(CPU_CNT_WIDTH > 32), CPU_CNT_WIDTH-32, 0));
|
|
|
-- HPM counter width - high/low parts --
|
-- HPM counter width - high/low parts --
|
constant hpm_cnt_lo_width_c : natural := natural(cond_sel_int_f(boolean(HPM_CNT_WIDTH < 32), HPM_CNT_WIDTH, 32));
|
constant hpm_cnt_lo_width_c : natural := natural(cond_sel_int_f(boolean(HPM_CNT_WIDTH < 32), HPM_CNT_WIDTH, 32));
|
constant hpm_cnt_hi_width_c : natural := natural(cond_sel_int_f(boolean(HPM_CNT_WIDTH > 32), HPM_CNT_WIDTH-32, 0));
|
constant hpm_cnt_hi_width_c : natural := natural(cond_sel_int_f(boolean(HPM_CNT_WIDTH > 32), HPM_CNT_WIDTH-32, 0));
|
|
|
-- instruction fetch engine --
|
-- instruction fetch engine --
|
type fetch_engine_state_t is (IFETCH_REQUEST, IFETCH_ISSUE);
|
type fetch_engine_state_t is (IFETCH_REQUEST, IFETCH_ISSUE);
|
type fetch_engine_t is record
|
type fetch_engine_t is record
|
state : fetch_engine_state_t;
|
state : fetch_engine_state_t;
|
state_nxt : fetch_engine_state_t;
|
state_nxt : fetch_engine_state_t;
|
state_prev : fetch_engine_state_t;
|
state_prev : fetch_engine_state_t;
|
restart : std_ulogic;
|
restart : std_ulogic;
|
restart_nxt : std_ulogic;
|
restart_nxt : std_ulogic;
|
|
align : std_ulogic;
|
|
align_nxt : std_ulogic;
|
pc : std_ulogic_vector(data_width_c-1 downto 0);
|
pc : std_ulogic_vector(data_width_c-1 downto 0);
|
pc_nxt : std_ulogic_vector(data_width_c-1 downto 0);
|
pc_nxt : std_ulogic_vector(data_width_c-1 downto 0);
|
reset : std_ulogic;
|
reset : std_ulogic;
|
bus_ir : std_ulogic;
|
bus_if : std_ulogic;
|
end record;
|
end record;
|
signal fetch_engine : fetch_engine_t;
|
signal fetch_engine : fetch_engine_t;
|
|
|
-- instruction prefetch buffer (FIFO) interface --
|
-- instruction prefetch buffer (FIFO) interface --
|
|
type ipb_data_t is array (0 to 1) of std_ulogic_vector((2+16)-1 downto 0); -- status (bus_error, align_error) + 16-bit instruction
|
type ipb_t is record
|
type ipb_t is record
|
wdata : std_ulogic_vector(2+31 downto 0); -- write status (bus_error, align_error) + 32-bit instruction data
|
wdata : ipb_data_t;
|
we : std_ulogic; -- trigger write
|
we : std_ulogic_vector(1 downto 0); -- trigger write
|
free : std_ulogic; -- free entry available?
|
free : std_ulogic_vector(1 downto 0); -- free entry available?
|
clear : std_ulogic; -- clear all entries
|
rdata : ipb_data_t;
|
--
|
re : std_ulogic_vector(1 downto 0); -- read enable
|
rdata : std_ulogic_vector(2+31 downto 0); -- read data: status (bus_error, align_error) + 32-bit instruction data
|
avail : std_ulogic_vector(1 downto 0); -- data available?
|
re : std_ulogic; -- read enable
|
|
avail : std_ulogic; -- data available?
|
|
end record;
|
end record;
|
signal ipb : ipb_t;
|
signal ipb : ipb_t;
|
|
|
-- pre-decoder --
|
|
signal ci_instr16 : std_ulogic_vector(15 downto 0);
|
|
signal ci_instr32 : std_ulogic_vector(31 downto 0);
|
|
signal ci_illegal : std_ulogic;
|
|
|
|
-- instruction issue engine --
|
-- instruction issue engine --
|
type issue_engine_t is record
|
type issue_engine_t is record
|
realign : std_ulogic;
|
|
realign_nxt : std_ulogic;
|
|
align : std_ulogic;
|
align : std_ulogic;
|
align_nxt : std_ulogic;
|
align_set : std_ulogic;
|
buf : std_ulogic_vector(2+15 downto 0);
|
align_clr : std_ulogic;
|
buf_nxt : std_ulogic_vector(2+15 downto 0);
|
ci_i16 : std_ulogic_vector(15 downto 0);
|
|
ci_i32 : std_ulogic_vector(31 downto 0);
|
|
ci_ill : std_ulogic;
|
|
data : std_ulogic_vector((4+32)-1 downto 0); -- 4-bit status + 32-bit instruction
|
|
valid : std_ulogic_vector(1 downto 0); -- data word is valid when != 0
|
end record;
|
end record;
|
signal issue_engine : issue_engine_t;
|
signal issue_engine : issue_engine_t;
|
|
|
-- instruction issue interface --
|
|
type cmd_issue_t is record
|
|
data : std_ulogic_vector(35 downto 0); -- 4-bit status + 32-bit instruction
|
|
valid : std_ulogic; -- data word is valid when set
|
|
end record;
|
|
signal cmd_issue : cmd_issue_t;
|
|
|
|
-- instruction decoding helper logic --
|
-- instruction decoding helper logic --
|
type decode_aux_t is record
|
type decode_aux_t is record
|
is_a_lr : std_ulogic;
|
is_a_lr : std_ulogic;
|
is_a_sc : std_ulogic;
|
is_a_sc : std_ulogic;
|
is_f_op : std_ulogic;
|
is_f_op : std_ulogic;
|
is_m_mul : std_ulogic;
|
is_m_mul : std_ulogic;
|
is_m_div : std_ulogic;
|
is_m_div : std_ulogic;
|
is_b_imm : std_ulogic;
|
is_b_imm : std_ulogic;
|
is_b_reg : std_ulogic;
|
is_b_reg : std_ulogic;
|
rs1_zero : std_ulogic;
|
rs1_zero : std_ulogic;
|
rd_zero : std_ulogic;
|
rd_zero : std_ulogic;
|
end record;
|
end record;
|
signal decode_aux : decode_aux_t;
|
signal decode_aux : decode_aux_t;
|
|
|
-- instruction execution engine --
|
-- instruction execution engine --
|
type execute_engine_state_t is (DISPATCH, TRAP_ENTER, TRAP_EXIT, TRAP_EXECUTE, EXECUTE, ALU_WAIT,
|
type execute_engine_state_t is (DISPATCH, TRAP_ENTER, TRAP_EXIT, TRAP_EXECUTE, EXECUTE, ALU_WAIT,
|
BRANCH, LOADSTORE_0, LOADSTORE_1, LOADSTORE_2, SYS_ENV, CSR_ACCESS);
|
BRANCH, BRANCHED, LOADSTORE_0, LOADSTORE_1, LOADSTORE_2, SYSTEM);
|
type execute_engine_t is record
|
type execute_engine_t is record
|
state : execute_engine_state_t;
|
state : execute_engine_state_t;
|
state_nxt : execute_engine_state_t;
|
state_nxt : execute_engine_state_t;
|
state_prev : execute_engine_state_t;
|
state_prev : execute_engine_state_t;
|
--
|
--
|
i_reg : std_ulogic_vector(31 downto 0);
|
i_reg : std_ulogic_vector(31 downto 0);
|
i_reg_nxt : std_ulogic_vector(31 downto 0);
|
i_reg_nxt : std_ulogic_vector(31 downto 0);
|
i_reg_last : std_ulogic_vector(31 downto 0); -- last executed instruction
|
i_reg_last : std_ulogic_vector(31 downto 0); -- last executed instruction
|
--
|
--
|
is_ci : std_ulogic; -- current instruction is de-compressed instruction
|
is_ci : std_ulogic; -- current instruction is de-compressed instruction
|
is_ci_nxt : std_ulogic;
|
is_ci_nxt : std_ulogic;
|
is_ici : std_ulogic; -- current instruction is illegal de-compressed instruction
|
is_ici : std_ulogic; -- current instruction is illegal de-compressed instruction
|
is_ici_nxt : std_ulogic;
|
is_ici_nxt : std_ulogic;
|
--
|
--
|
branch_taken : std_ulogic; -- branch condition fulfilled
|
branch_taken : std_ulogic; -- branch condition fulfilled
|
pc : std_ulogic_vector(data_width_c-1 downto 0); -- actual PC, corresponding to current executed instruction
|
pc : std_ulogic_vector(data_width_c-1 downto 0); -- actual PC, corresponding to current executed instruction
|
pc_mux_sel : std_ulogic; -- source select for PC update
|
pc_mux_sel : std_ulogic; -- source select for PC update
|
pc_we : std_ulogic; -- PC update enabled
|
pc_we : std_ulogic; -- PC update enabled
|
next_pc : std_ulogic_vector(data_width_c-1 downto 0); -- next PC, corresponding to next instruction to be executed
|
next_pc : std_ulogic_vector(data_width_c-1 downto 0); -- next PC, corresponding to next instruction to be executed
|
next_pc_inc : std_ulogic_vector(data_width_c-1 downto 0); -- increment to get next PC
|
next_pc_inc : std_ulogic_vector(data_width_c-1 downto 0); -- increment to get next PC
|
pc_last : std_ulogic_vector(data_width_c-1 downto 0); -- PC of last executed instruction
|
pc_last : std_ulogic_vector(data_width_c-1 downto 0); -- PC of last executed instruction
|
--
|
--
|
sleep : std_ulogic; -- CPU in sleep mode
|
sleep : std_ulogic; -- CPU in sleep mode
|
sleep_nxt : std_ulogic;
|
sleep_nxt : std_ulogic;
|
branched : std_ulogic; -- instruction fetch was reset
|
branched : std_ulogic; -- instruction fetch was reset
|
branched_nxt : std_ulogic;
|
branched_nxt : std_ulogic;
|
end record;
|
end record;
|
signal execute_engine : execute_engine_t;
|
signal execute_engine : execute_engine_t;
|
|
|
-- trap controller --
|
-- trap controller --
|
type trap_ctrl_t is record
|
type trap_ctrl_t is record
|
exc_buf : std_ulogic_vector(exc_width_c-1 downto 0);
|
exc_buf : std_ulogic_vector(exc_width_c-1 downto 0);
|
exc_fire : std_ulogic; -- set if there is a valid source in the exception buffer
|
exc_fire : std_ulogic; -- set if there is a valid source in the exception buffer
|
irq_buf : std_ulogic_vector(irq_width_c-1 downto 0);
|
irq_buf : std_ulogic_vector(irq_width_c-1 downto 0);
|
irq_fire : std_ulogic; -- set if there is a valid source in the interrupt buffer
|
irq_fire : std_ulogic; -- set if there is a valid source in the interrupt buffer
|
cause : std_ulogic_vector(6 downto 0); -- trap ID for mcause CSR
|
cause : std_ulogic_vector(6 downto 0); -- trap ID for mcause CSR
|
cause_nxt : std_ulogic_vector(6 downto 0);
|
cause_nxt : std_ulogic_vector(6 downto 0);
|
db_irq_fire : std_ulogic; -- set if there is a valid IRQ source in the "enter debug mode" trap buffer
|
db_irq_fire : std_ulogic; -- set if there is a valid IRQ source in the "enter debug mode" trap buffer
|
db_irq_en : std_ulogic; -- set if IRQs are allowed in debug mode
|
db_irq_en : std_ulogic; -- set if IRQs are allowed in debug mode
|
--
|
--
|
env_start : std_ulogic; -- start trap handler env
|
env_start : std_ulogic; -- start trap handler env
|
env_start_ack : std_ulogic; -- start of trap handler acknowledged
|
env_start_ack : std_ulogic; -- start of trap handler acknowledged
|
env_end : std_ulogic; -- end trap handler env
|
env_end : std_ulogic; -- end trap handler env
|
--
|
--
|
instr_be : std_ulogic; -- instruction fetch bus error
|
instr_be : std_ulogic; -- instruction fetch bus error
|
instr_ma : std_ulogic; -- instruction fetch misaligned address
|
instr_ma : std_ulogic; -- instruction fetch misaligned address
|
instr_il : std_ulogic; -- illegal instruction
|
instr_il : std_ulogic; -- illegal instruction
|
env_call : std_ulogic; -- ecall instruction
|
env_call : std_ulogic; -- ecall instruction
|
break_point : std_ulogic; -- ebreak instruction
|
break_point : std_ulogic; -- ebreak instruction
|
end record;
|
end record;
|
signal trap_ctrl : trap_ctrl_t;
|
signal trap_ctrl : trap_ctrl_t;
|
|
|
-- CPU main control bus --
|
-- CPU main control bus --
|
signal ctrl_nxt, ctrl : std_ulogic_vector(ctrl_width_c-1 downto 0);
|
signal ctrl_nxt, ctrl : std_ulogic_vector(ctrl_width_c-1 downto 0);
|
|
|
-- RISC-V control and status registers (CSRs) --
|
-- RISC-V control and status registers (CSRs) --
|
type pmpcfg_t is array (0 to 15) of std_ulogic_vector(7 downto 0);
|
type pmpcfg_t is array (0 to 15) of std_ulogic_vector(7 downto 0);
|
type pmpaddr_t is array (0 to PMP_NUM_REGIONS-1) of std_ulogic_vector(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2);
|
type pmpaddr_t is array (0 to PMP_NUM_REGIONS-1) of std_ulogic_vector(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2);
|
type mhpmevent_t is array (0 to HPM_NUM_CNTS-1) of std_ulogic_vector(hpmcnt_event_size_c-1 downto 0);
|
type mhpmevent_t is array (0 to HPM_NUM_CNTS-1) of std_ulogic_vector(hpmcnt_event_size_c-1 downto 0);
|
type mhpmevent_rd_t is array (0 to 28) of std_ulogic_vector(data_width_c-1 downto 0);
|
type mhpmevent_rd_t is array (0 to 28) of std_ulogic_vector(data_width_c-1 downto 0);
|
type mhpmcnt_t is array (0 to HPM_NUM_CNTS-1) of std_ulogic_vector(data_width_c-1 downto 0);
|
type mhpmcnt_t is array (0 to HPM_NUM_CNTS-1) of std_ulogic_vector(data_width_c-1 downto 0);
|
type mhpmcnt_nxt_t is array (0 to HPM_NUM_CNTS-1) of std_ulogic_vector(data_width_c downto 0);
|
type mhpmcnt_nxt_t is array (0 to HPM_NUM_CNTS-1) of std_ulogic_vector(data_width_c downto 0);
|
type mhpmcnt_ovfl_t is array (0 to HPM_NUM_CNTS-1) of std_ulogic_vector(0 downto 0);
|
type mhpmcnt_ovfl_t is array (0 to HPM_NUM_CNTS-1) of std_ulogic_vector(0 downto 0);
|
type mhpmcnt_rd_t is array (0 to 29) of std_ulogic_vector(data_width_c-1 downto 0);
|
type mhpmcnt_rd_t is array (0 to 29) of std_ulogic_vector(data_width_c-1 downto 0);
|
type csr_t is record
|
type csr_t is record
|
addr : std_ulogic_vector(11 downto 0); -- csr address
|
addr : std_ulogic_vector(11 downto 0); -- csr address
|
we : std_ulogic; -- csr write enable
|
we : std_ulogic; -- csr write enable
|
we_nxt : std_ulogic;
|
we_nxt : std_ulogic;
|
|
re : std_ulogic; -- csr read enable
|
|
re_nxt : std_ulogic;
|
wdata : std_ulogic_vector(data_width_c-1 downto 0); -- csr write data
|
wdata : std_ulogic_vector(data_width_c-1 downto 0); -- csr write data
|
rdata : std_ulogic_vector(data_width_c-1 downto 0); -- csr read data
|
rdata : std_ulogic_vector(data_width_c-1 downto 0); -- csr read data
|
--
|
--
|
mstatus_mie : std_ulogic; -- mstatus.MIE: global IRQ enable (R/W)
|
mstatus_mie : std_ulogic; -- mstatus.MIE: global IRQ enable (R/W)
|
mstatus_mpie : std_ulogic; -- mstatus.MPIE: previous global IRQ enable (R/W)
|
mstatus_mpie : std_ulogic; -- mstatus.MPIE: previous global IRQ enable (R/W)
|
mstatus_mpp : std_ulogic; -- mstatus.MPP: machine previous privilege mode
|
mstatus_mpp : std_ulogic; -- mstatus.MPP: machine previous privilege mode
|
mstatus_tw : std_ulogic; -- mstatus.TW: do not allow user mode to execute WFI instruction when set
|
mstatus_tw : std_ulogic; -- mstatus.TW: do not allow user mode to execute WFI instruction when set
|
--
|
--
|
mie_msie : std_ulogic; -- mie.MSIE: machine software interrupt enable (R/W)
|
mie_msie : std_ulogic; -- mie.MSIE: machine software interrupt enable (R/W)
|
mie_meie : std_ulogic; -- mie.MEIE: machine external interrupt enable (R/W)
|
mie_meie : std_ulogic; -- mie.MEIE: machine external interrupt enable (R/W)
|
mie_mtie : std_ulogic; -- mie.MEIE: machine timer interrupt enable (R/W)
|
mie_mtie : std_ulogic; -- mie.MEIE: machine timer interrupt enable (R/W)
|
mie_firqe : std_ulogic_vector(15 downto 0); -- mie.firq*e: fast interrupt enabled (R/W)
|
mie_firqe : std_ulogic_vector(15 downto 0); -- mie.firq*e: fast interrupt enabled (R/W)
|
--
|
--
|
mip_firq_nclr : std_ulogic_vector(15 downto 0); -- clear pending FIRQ (active-low)
|
mip_firq_nclr : std_ulogic_vector(15 downto 0); -- clear pending FIRQ (active-low)
|
--
|
--
|
mcounteren_cy : std_ulogic; -- mcounteren.cy: allow cycle[h] access from user-mode
|
mcounteren_cy : std_ulogic; -- mcounteren.cy: allow cycle[h] access from user-mode
|
mcounteren_tm : std_ulogic; -- mcounteren.tm: allow time[h] access from user-mode
|
mcounteren_tm : std_ulogic; -- mcounteren.tm: allow time[h] access from user-mode
|
mcounteren_ir : std_ulogic; -- mcounteren.ir: allow instret[h] access from user-mode
|
mcounteren_ir : std_ulogic; -- mcounteren.ir: allow instret[h] access from user-mode
|
--
|
--
|
mcountinhibit_cy : std_ulogic; -- mcounterinhibit.cy: enable auto-increment for [m]cycle[h]
|
mcountinhibit_cy : std_ulogic; -- mcounterinhibit.cy: enable auto-increment for [m]cycle[h]
|
mcountinhibit_ir : std_ulogic; -- mcounterinhibit.ir: enable auto-increment for [m]instret[h]
|
mcountinhibit_ir : std_ulogic; -- mcounterinhibit.ir: enable auto-increment for [m]instret[h]
|
mcountinhibit_hpm : std_ulogic_vector(HPM_NUM_CNTS-1 downto 0); -- mcounterinhibit.hpm3: enable auto-increment for mhpmcounterx[h]
|
mcountinhibit_hpm : std_ulogic_vector(HPM_NUM_CNTS-1 downto 0); -- mcounterinhibit.hpm3: enable auto-increment for mhpmcounterx[h]
|
--
|
--
|
privilege : std_ulogic; -- current privilege mode
|
privilege : std_ulogic; -- current privilege mode
|
privilege_eff : std_ulogic; -- current *effective* privilege mode
|
privilege_eff : std_ulogic; -- current *effective* privilege mode
|
--
|
--
|
mepc : std_ulogic_vector(data_width_c-1 downto 0); -- mepc: machine exception pc (R/W)
|
mepc : std_ulogic_vector(data_width_c-1 downto 0); -- mepc: machine exception pc (R/W)
|
mcause : std_ulogic_vector(5 downto 0); -- mcause: machine trap cause (R/W)
|
mcause : std_ulogic_vector(5 downto 0); -- mcause: machine trap cause (R/W)
|
mtvec : std_ulogic_vector(data_width_c-1 downto 0); -- mtvec: machine trap-handler base address (R/W), bit 1:0 == 00
|
mtvec : std_ulogic_vector(data_width_c-1 downto 0); -- mtvec: machine trap-handler base address (R/W), bit 1:0 == 00
|
mtval : std_ulogic_vector(data_width_c-1 downto 0); -- mtval: machine bad address or instruction (R/W)
|
mtval : std_ulogic_vector(data_width_c-1 downto 0); -- mtval: machine bad address or instruction (R/W)
|
--
|
--
|
mhpmevent : mhpmevent_t; -- mhpmevent*: machine performance-monitoring event selector (R/W)
|
mhpmevent : mhpmevent_t; -- mhpmevent*: machine performance-monitoring event selector (R/W)
|
mhpmevent_rd : mhpmevent_rd_t; -- read data
|
mhpmevent_rd : mhpmevent_rd_t; -- read data
|
--
|
--
|
mscratch : std_ulogic_vector(data_width_c-1 downto 0); -- mscratch: scratch register (R/W)
|
mscratch : std_ulogic_vector(data_width_c-1 downto 0); -- mscratch: scratch register (R/W)
|
--
|
--
|
mcycle : std_ulogic_vector(data_width_c-1 downto 0); -- mcycle (R/W)
|
mcycle : std_ulogic_vector(data_width_c-1 downto 0); -- mcycle (R/W)
|
mcycle_nxt : std_ulogic_vector(data_width_c downto 0);
|
mcycle_nxt : std_ulogic_vector(data_width_c downto 0);
|
mcycle_ovfl : std_ulogic_vector(00 downto 0); -- counter low-to-high-word overflow
|
mcycle_ovfl : std_ulogic_vector(00 downto 0); -- counter low-to-high-word overflow
|
mcycleh : std_ulogic_vector(data_width_c-1 downto 0); -- mcycleh (R/W)
|
mcycleh : std_ulogic_vector(data_width_c-1 downto 0); -- mcycleh (R/W)
|
minstret : std_ulogic_vector(data_width_c-1 downto 0); -- minstret (R/W)
|
minstret : std_ulogic_vector(data_width_c-1 downto 0); -- minstret (R/W)
|
minstret_nxt : std_ulogic_vector(data_width_c downto 0);
|
minstret_nxt : std_ulogic_vector(data_width_c downto 0);
|
minstret_ovfl : std_ulogic_vector(00 downto 0); -- counter low-to-high-word overflow
|
minstret_ovfl : std_ulogic_vector(00 downto 0); -- counter low-to-high-word overflow
|
minstreth : std_ulogic_vector(data_width_c-1 downto 0); -- minstreth (R/W)
|
minstreth : std_ulogic_vector(data_width_c-1 downto 0); -- minstreth (R/W)
|
--
|
--
|
mhpmcounter : mhpmcnt_t; -- mhpmcounter* (R/W), plus carry bit
|
mhpmcounter : mhpmcnt_t; -- mhpmcounter* (R/W), plus carry bit
|
mhpmcounter_nxt : mhpmcnt_nxt_t;
|
mhpmcounter_nxt : mhpmcnt_nxt_t;
|
mhpmcounter_ovfl : mhpmcnt_ovfl_t; -- counter low-to-high-word overflow
|
mhpmcounter_ovfl : mhpmcnt_ovfl_t; -- counter low-to-high-word overflow
|
mhpmcounterh : mhpmcnt_t; -- mhpmcounter*h (R/W)
|
mhpmcounterh : mhpmcnt_t; -- mhpmcounter*h (R/W)
|
mhpmcounter_rd : mhpmcnt_rd_t; -- mhpmcounter* (R/W): actual read data
|
mhpmcounter_rd : mhpmcnt_rd_t; -- mhpmcounter* (R/W): actual read data
|
mhpmcounterh_rd : mhpmcnt_rd_t; -- mhpmcounter*h (R/W): actual read data
|
mhpmcounterh_rd : mhpmcnt_rd_t; -- mhpmcounter*h (R/W): actual read data
|
--
|
--
|
pmpcfg : pmpcfg_t; -- physical memory protection - configuration registers
|
pmpcfg : pmpcfg_t; -- physical memory protection - configuration registers
|
pmpaddr : pmpaddr_t; -- physical memory protection - address registers (bits 33:2 of PHYSICAL address)
|
pmpaddr : pmpaddr_t; -- physical memory protection - address registers (bits 33:2 of PHYSICAL address)
|
--
|
--
|
frm : std_ulogic_vector(02 downto 0); -- frm (R/W): FPU rounding mode
|
frm : std_ulogic_vector(02 downto 0); -- frm (R/W): FPU rounding mode
|
fflags : std_ulogic_vector(04 downto 0); -- fflags (R/W): FPU exception flags
|
fflags : std_ulogic_vector(04 downto 0); -- fflags (R/W): FPU exception flags
|
--
|
--
|
dcsr_ebreakm : std_ulogic; -- dcsr.ebreakm (R/W): behavior of ebreak instruction on m-mode
|
dcsr_ebreakm : std_ulogic; -- dcsr.ebreakm (R/W): behavior of ebreak instruction on m-mode
|
dcsr_ebreaku : std_ulogic; -- dcsr.ebreaku (R/W): behavior of ebreak instruction on u-mode
|
dcsr_ebreaku : std_ulogic; -- dcsr.ebreaku (R/W): behavior of ebreak instruction on u-mode
|
dcsr_step : std_ulogic; -- dcsr.step (R/W): single-step mode
|
dcsr_step : std_ulogic; -- dcsr.step (R/W): single-step mode
|
dcsr_prv : std_ulogic; -- dcsr.prv (R/W): current privilege level when entering debug mode
|
dcsr_prv : std_ulogic; -- dcsr.prv (R/W): current privilege level when entering debug mode
|
dcsr_cause : std_ulogic_vector(02 downto 0); -- dcsr.cause (R/-): why was debug mode entered
|
dcsr_cause : std_ulogic_vector(02 downto 0); -- dcsr.cause (R/-): why was debug mode entered
|
dcsr_rd : std_ulogic_vector(data_width_c-1 downto 0); -- dcsr (R/(W)): debug mode control and status register
|
dcsr_rd : std_ulogic_vector(data_width_c-1 downto 0); -- dcsr (R/(W)): debug mode control and status register
|
dpc : std_ulogic_vector(data_width_c-1 downto 0); -- dpc (R/W): debug mode program counter
|
dpc : std_ulogic_vector(data_width_c-1 downto 0); -- dpc (R/W): debug mode program counter
|
dscratch0 : std_ulogic_vector(data_width_c-1 downto 0); -- dscratch0 (R/W): debug mode scratch register 0
|
dscratch0 : std_ulogic_vector(data_width_c-1 downto 0); -- dscratch0 (R/W): debug mode scratch register 0
|
--
|
--
|
tdata1_exe : std_ulogic; -- enable (match) trigger
|
tdata1_exe : std_ulogic; -- enable (match) trigger
|
tdata1_rd : std_ulogic_vector(data_width_c-1 downto 0); -- tdata1 (R/(W)): trigger register read-back
|
tdata1_rd : std_ulogic_vector(data_width_c-1 downto 0); -- tdata1 (R/(W)): trigger register read-back
|
tdata2 : std_ulogic_vector(data_width_c-1 downto 0); -- tdata2 (R/W): address-match register
|
tdata2 : std_ulogic_vector(data_width_c-1 downto 0); -- tdata2 (R/W): address-match register
|
end record;
|
end record;
|
signal csr : csr_t;
|
signal csr : csr_t;
|
|
|
-- debug mode controller --
|
-- debug mode controller --
|
type debug_ctrl_state_t is (DEBUG_OFFLINE, DEBUG_PENDING, DEBUG_ONLINE, DEBUG_EXIT);
|
type debug_ctrl_state_t is (DEBUG_OFFLINE, DEBUG_PENDING, DEBUG_ONLINE, DEBUG_EXIT);
|
type debug_ctrl_t is record
|
type debug_ctrl_t is record
|
state : debug_ctrl_state_t;
|
state : debug_ctrl_state_t;
|
-- decoded state --
|
-- decoded state --
|
running : std_ulogic; -- debug mode active
|
running : std_ulogic; -- debug mode active
|
pending : std_ulogic; -- waiting to start debug mode
|
pending : std_ulogic; -- waiting to start debug mode
|
-- entering triggers --
|
-- entering triggers --
|
trig_hw : std_ulogic; -- hardware trigger
|
trig_hw : std_ulogic; -- hardware trigger
|
trig_break : std_ulogic; -- ebreak instruction
|
trig_break : std_ulogic; -- ebreak instruction
|
trig_halt : std_ulogic; -- external request
|
trig_halt : std_ulogic; -- external request
|
trig_step : std_ulogic; -- single-stepping mode
|
trig_step : std_ulogic; -- single-stepping mode
|
-- leave debug mode --
|
-- leave debug mode --
|
dret : std_ulogic; -- executed DRET instruction
|
dret : std_ulogic; -- executed DRET instruction
|
-- misc --
|
-- misc --
|
ext_halt_req : std_ulogic;
|
ext_halt_req : std_ulogic;
|
end record;
|
end record;
|
signal debug_ctrl : debug_ctrl_t;
|
signal debug_ctrl : debug_ctrl_t;
|
|
|
-- (hpm) counter events --
|
-- (hpm) counter events --
|
signal cnt_event : std_ulogic_vector(hpmcnt_event_size_c-1 downto 0);
|
signal cnt_event : std_ulogic_vector(hpmcnt_event_size_c-1 downto 0);
|
signal hpmcnt_trigger : std_ulogic_vector(HPM_NUM_CNTS-1 downto 0);
|
signal hpmcnt_trigger : std_ulogic_vector(HPM_NUM_CNTS-1 downto 0);
|
|
|
-- illegal instruction check --
|
-- illegal instruction check --
|
signal illegal_opcode_lsbs : std_ulogic; -- opcode != rv32
|
signal illegal_cmd : std_ulogic;
|
signal illegal_instruction : std_ulogic;
|
signal illegal_reg : std_ulogic; -- illegal register (>x15) - E-extension
|
signal illegal_register : std_ulogic; -- illegal register (>x15) - E-extension
|
|
signal illegal_compressed : std_ulogic; -- illegal compressed instruction - C-extension
|
|
|
|
-- access (privilege) check --
|
-- access (privilege) check --
|
signal csr_acc_valid : std_ulogic; -- valid CSR access (implemented and valid access rights)
|
signal csr_acc_valid : std_ulogic; -- valid CSR access (implemented and valid access rights)
|
|
|
-- hardware trigger module --
|
-- hardware trigger module --
|
signal hw_trigger_fire : std_ulogic;
|
signal hw_trigger_fire : std_ulogic;
|
|
|
begin
|
begin
|
|
|
-- ****************************************************************************************************************************
|
-- ****************************************************************************************************************************
|
-- Instruction Fetch (always fetch 32-bit-aligned 32-bit chunks of data)
|
-- Instruction Fetch (always fetch 32-bit-aligned 32-bit chunks of data)
|
-- ****************************************************************************************************************************
|
-- ****************************************************************************************************************************
|
|
|
-- Fetch Engine FSM Sync ------------------------------------------------------------------
|
-- Fetch Engine FSM Sync ------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
fetch_engine_fsm_sync: process(rstn_i, clk_i)
|
fetch_engine_fsm_sync: process(rstn_i, clk_i)
|
begin
|
begin
|
if (rstn_i = '0') then
|
if (rstn_i = '0') then
|
fetch_engine.state <= IFETCH_REQUEST;
|
fetch_engine.state <= IFETCH_REQUEST;
|
fetch_engine.state_prev <= IFETCH_REQUEST;
|
fetch_engine.state_prev <= IFETCH_REQUEST;
|
fetch_engine.restart <= '1';
|
fetch_engine.restart <= '1';
|
|
fetch_engine.align <= '0'; -- always start at aligned address after reset
|
fetch_engine.pc <= (others => def_rst_val_c);
|
fetch_engine.pc <= (others => def_rst_val_c);
|
elsif rising_edge(clk_i) then
|
elsif rising_edge(clk_i) then
|
fetch_engine.state <= fetch_engine.state_nxt;
|
fetch_engine.state <= fetch_engine.state_nxt;
|
fetch_engine.state_prev <= fetch_engine.state;
|
fetch_engine.state_prev <= fetch_engine.state;
|
fetch_engine.restart <= fetch_engine.restart_nxt or fetch_engine.reset;
|
fetch_engine.restart <= fetch_engine.restart_nxt or fetch_engine.reset;
|
|
fetch_engine.align <= fetch_engine.align_nxt and bool_to_ulogic_f(CPU_EXTENSION_RISCV_C);
|
fetch_engine.pc <= fetch_engine.pc_nxt;
|
fetch_engine.pc <= fetch_engine.pc_nxt;
|
end if;
|
end if;
|
end process fetch_engine_fsm_sync;
|
end process fetch_engine_fsm_sync;
|
|
|
-- PC output --
|
-- PC output --
|
fetch_pc_o <= fetch_engine.pc(data_width_c-1 downto 1) & '0'; -- half-word aligned
|
fetch_pc_o <= fetch_engine.pc(data_width_c-1 downto 1) & '0'; -- half-word aligned
|
|
|
|
|
-- Fetch Engine FSM Comb ------------------------------------------------------------------
|
-- Fetch Engine FSM Comb ------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
fetch_engine_fsm_comb: process(fetch_engine, execute_engine, ipb, instr_i, bus_i_wait_i, be_instr_i, ma_instr_i)
|
fetch_engine_fsm_comb: process(fetch_engine, execute_engine, ipb, instr_i, bus_i_wait_i, be_instr_i, ma_instr_i)
|
begin
|
begin
|
-- arbiter defaults --
|
-- arbiter defaults --
|
fetch_engine.bus_ir <= '0';
|
fetch_engine.bus_if <= '0';
|
fetch_engine.state_nxt <= fetch_engine.state;
|
fetch_engine.state_nxt <= fetch_engine.state;
|
fetch_engine.pc_nxt <= fetch_engine.pc;
|
fetch_engine.pc_nxt <= fetch_engine.pc;
|
fetch_engine.restart_nxt <= fetch_engine.restart;
|
fetch_engine.restart_nxt <= fetch_engine.restart;
|
|
fetch_engine.align_nxt <= fetch_engine.align;
|
|
|
-- instruction prefetch buffer defaults --
|
-- instruction prefetch buffer defaults --
|
ipb.we <= '0';
|
ipb.we <= "00";
|
ipb.wdata <= be_instr_i & ma_instr_i & instr_i(31 downto 0); -- store exception info and instruction word
|
ipb.wdata(0) <= be_instr_i & ma_instr_i & instr_i(15 downto 00);
|
|
ipb.wdata(1) <= be_instr_i & ma_instr_i & instr_i(31 downto 16);
|
|
|
-- state machine --
|
-- state machine --
|
if (fetch_engine.state = IFETCH_REQUEST) then -- IFETCH_REQUEST: request new 32-bit-aligned instruction word
|
if (fetch_engine.state = IFETCH_REQUEST) then -- REQUEST: request new 32-bit-aligned instruction word
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
if (fetch_engine.restart = '1') then -- reset request
|
if (fetch_engine.restart = '1') then -- reset request
|
fetch_engine.pc_nxt <= execute_engine.pc(data_width_c-1 downto 1) & '0'; -- initialize with "real" application PC
|
fetch_engine.pc_nxt <= execute_engine.pc(data_width_c-1 downto 1) & '0'; -- initialize with "real" application PC
|
elsif (ipb.free = '1') then -- free entry in buffer
|
fetch_engine.align_nxt <= execute_engine.pc(1);
|
fetch_engine.bus_ir <= '1'; -- instruction fetch request
|
elsif (ipb.free = "11") then -- free entries in both buffers
|
|
fetch_engine.bus_if <= '1'; -- instruction fetch request
|
fetch_engine.state_nxt <= IFETCH_ISSUE;
|
fetch_engine.state_nxt <= IFETCH_ISSUE;
|
end if;
|
end if;
|
fetch_engine.restart_nxt <= '0';
|
fetch_engine.restart_nxt <= '0'; -- restart done
|
|
|
else -- IFETCH_ISSUE: store instruction data to prefetch buffer
|
else -- ISSUE: store instruction data to prefetch buffer
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
if (bus_i_wait_i = '0') or (be_instr_i = '1') or (ma_instr_i = '1') then -- wait for bus response
|
if (bus_i_wait_i = '0') or (be_instr_i = '1') or (ma_instr_i = '1') then -- wait for bus response
|
fetch_engine.pc_nxt <= std_ulogic_vector(unsigned(fetch_engine.pc) + 4);
|
fetch_engine.pc_nxt <= std_ulogic_vector(unsigned(fetch_engine.pc) + 4);
|
ipb.we <= not fetch_engine.restart; -- write to IPB if not being reset
|
fetch_engine.align_nxt <= '0';
|
fetch_engine.state_nxt <= IFETCH_REQUEST;
|
fetch_engine.state_nxt <= IFETCH_REQUEST;
|
|
if (fetch_engine.restart = '0') then -- write to IPB if not being reset
|
|
ipb.we(0) <= not fetch_engine.align; -- not start at unaligned address
|
|
ipb.we(1) <= '1';
|
|
end if;
|
end if;
|
end if;
|
|
|
end if;
|
end if;
|
end process fetch_engine_fsm_comb;
|
end process fetch_engine_fsm_comb;
|
|
|
-- clear instruction prefetch buffer while being reset --
|
|
ipb.clear <= fetch_engine.restart or fetch_engine.reset;
|
|
|
|
|
|
-- ****************************************************************************************************************************
|
-- ****************************************************************************************************************************
|
-- Instruction Prefetch Buffer
|
-- Instruction Prefetch Buffer
|
-- ****************************************************************************************************************************
|
-- ****************************************************************************************************************************
|
|
|
-- Instruction Prefetch Buffer (FIFO) -----------------------------------------------------
|
-- Instruction Prefetch Buffer (FIFO) -----------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
instr_prefetch_buffer: neorv32_fifo
|
prefetch_buffer:
|
|
for i in 0 to 1 generate -- high half-word and low half-word
|
|
prefetch_buffer_inst: neorv32_fifo
|
generic map (
|
generic map (
|
FIFO_DEPTH => CPU_IPB_ENTRIES, -- number of fifo entries; has to be a power of two; min 1
|
FIFO_DEPTH => CPU_IPB_ENTRIES, -- number of fifo entries; has to be a power of two; min 1
|
FIFO_WIDTH => ipb.wdata'length, -- size of data elements in fifo
|
FIFO_WIDTH => ipb.wdata(i)'length, -- size of data elements in fifo
|
FIFO_RSYNC => false, -- we NEED to read data asynchronously
|
FIFO_RSYNC => false, -- we NEED to read data asynchronously
|
FIFO_SAFE => false -- no safe access required (ensured by FIFO-external control)
|
FIFO_SAFE => false -- no safe access required (ensured by FIFO-external control)
|
)
|
)
|
port map (
|
port map (
|
-- control --
|
-- control --
|
clk_i => clk_i, -- clock, rising edge
|
clk_i => clk_i, -- clock, rising edge
|
rstn_i => '1', -- async reset, low-active
|
rstn_i => '1', -- async reset, low-active
|
clear_i => ipb.clear, -- sync reset, high-active
|
clear_i => fetch_engine.restart, -- sync reset, high-active
|
level_o => open,
|
level_o => open,
|
half_o => open,
|
half_o => open,
|
-- write port --
|
-- write port --
|
wdata_i => ipb.wdata, -- write data
|
wdata_i => ipb.wdata(i), -- write data
|
we_i => ipb.we, -- write enable
|
we_i => ipb.we(i), -- write enable
|
free_o => ipb.free, -- at least one entry is free when set
|
free_o => ipb.free(i), -- at least one entry is free when set
|
-- read port --
|
-- read port --
|
re_i => ipb.re, -- read enable
|
re_i => ipb.re(i), -- read enable
|
rdata_o => ipb.rdata, -- read data
|
rdata_o => ipb.rdata(i), -- read data
|
avail_o => ipb.avail -- data available when set
|
avail_o => ipb.avail(i) -- data available when set
|
);
|
);
|
|
end generate;
|
|
|
|
|
-- ****************************************************************************************************************************
|
-- ****************************************************************************************************************************
|
-- Instruction Issue (recoding of compressed instructions and 32-bit instruction word construction)
|
-- Instruction Issue (decompress 16-bit instructions and assemble 32-bit instruction word)
|
-- ****************************************************************************************************************************
|
-- ****************************************************************************************************************************
|
|
|
-- Issue Engine FSM Sync ------------------------------------------------------------------
|
-- Issue Engine FSM Sync ------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
issue_engine_fsm_sync: process(rstn_i, clk_i)
|
issue_engine_fsm_sync: process(rstn_i, clk_i)
|
begin
|
begin
|
if (rstn_i = '0') then -- always start aligned after reset
|
if (rstn_i = '0') then
|
issue_engine.align <= '0';
|
issue_engine.align <= '0'; -- always start aligned after reset
|
issue_engine.realign <= '0';
|
|
issue_engine.buf <= (others => def_rst_val_c);
|
|
elsif rising_edge(clk_i) then
|
elsif rising_edge(clk_i) then
|
if (ipb.clear = '1') then
|
if (CPU_EXTENSION_RISCV_C = true) then
|
if (CPU_EXTENSION_RISCV_C = true) and (execute_engine.pc(1) = '1') then -- branch to unaligned address?
|
if (fetch_engine.restart = '1') then
|
issue_engine.align <= '1'; -- aligned on 16-bit boundary
|
issue_engine.align <= execute_engine.pc(1); -- branch to unaligned address?
|
issue_engine.realign <= '1';
|
elsif (execute_engine.state = DISPATCH) then
|
else
|
issue_engine.align <= (issue_engine.align and (not issue_engine.align_clr)) or issue_engine.align_set;
|
issue_engine.align <= '0'; -- aligned on 32-bit boundary
|
|
issue_engine.realign <= '0';
|
|
end if;
|
end if;
|
else
|
else
|
issue_engine.align <= issue_engine.align_nxt;
|
issue_engine.align <= '0'; -- always aligned
|
issue_engine.realign <= issue_engine.realign_nxt;
|
|
end if;
|
end if;
|
issue_engine.buf <= issue_engine.buf_nxt;
|
|
end if;
|
end if;
|
end process issue_engine_fsm_sync;
|
end process issue_engine_fsm_sync;
|
|
|
|
|
-- Issue Engine FSM Comb ------------------------------------------------------------------
|
-- Issue Engine FSM Comb ------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
issue_engine_fsm_comb: process(issue_engine, ipb, execute_engine, ci_illegal, ci_instr32)
|
issue_engine_fsm_comb: process(issue_engine.align, ipb)
|
begin
|
begin
|
-- arbiter defaults --
|
-- defaults --
|
issue_engine.realign_nxt <= issue_engine.realign;
|
issue_engine.align_set <= '0';
|
issue_engine.align_nxt <= issue_engine.align;
|
issue_engine.align_clr <= '0';
|
issue_engine.buf_nxt <= issue_engine.buf;
|
issue_engine.valid <= "00";
|
|
|
-- instruction prefetch buffer interface defaults --
|
-- start with LOW half-word --
|
ipb.re <= '0';
|
if (issue_engine.align = '0') or (CPU_EXTENSION_RISCV_C = false) then
|
|
if (CPU_EXTENSION_RISCV_C = true) and (ipb.rdata(0)(1 downto 0) /= "11") then -- compressed
|
-- instruction issue interface defaults --
|
issue_engine.align_set <= ipb.avail(0); -- start of next instruction word is not 32-bit aligned
|
cmd_issue.valid <= '0';
|
issue_engine.valid(0) <= ipb.avail(0);
|
|
issue_engine.data <= issue_engine.ci_ill & ipb.rdata(0)(17 downto 16) & '1' & issue_engine.ci_i32;
|
-- construct instruction data --
|
else -- aligned uncompressed
|
-- cmd_issue.data = <illegal_compressed_instruction> & <bus_error & alignment_error> & <is_compressed_instrucion> & <32-bit_instruction_word>
|
issue_engine.valid <= (others => (ipb.avail(0) and ipb.avail(1)));
|
if (issue_engine.align = '0') or (CPU_EXTENSION_RISCV_C = false) then -- 32-bit aligned
|
issue_engine.data <= '0' & (ipb.rdata(1)(17 downto 16) or ipb.rdata(0)(17 downto 16)) &
|
if (ipb.rdata(1 downto 0) = "11") or (CPU_EXTENSION_RISCV_C = false) then -- uncompressed
|
'0' & (ipb.rdata(1)(15 downto 00) & ipb.rdata(0)(15 downto 00));
|
cmd_issue.data <= '0' & ipb.rdata(33 downto 32) & '0' & ipb.rdata(31 downto 0);
|
end if;
|
else -- compressed
|
-- start with HIGH half-word --
|
cmd_issue.data <= ci_illegal & ipb.rdata(33 downto 32) & '1' & ci_instr32;
|
else
|
end if;
|
if (CPU_EXTENSION_RISCV_C = true) and (ipb.rdata(1)(1 downto 0) /= "11") then -- compressed
|
else -- not 32-bit aligned
|
issue_engine.align_clr <= ipb.avail(1); -- start of next instruction word is 32-bit aligned again
|
if (issue_engine.buf(1 downto 0) = "11") then -- uncompressed
|
issue_engine.valid(1) <= ipb.avail(1);
|
cmd_issue.data <= '0' & (ipb.rdata(33 downto 32) or issue_engine.buf(17 downto 16)) & '0' & (ipb.rdata(15 downto 0) & issue_engine.buf(15 downto 0));
|
issue_engine.data <= issue_engine.ci_ill & ipb.rdata(1)(17 downto 16) & '1' & issue_engine.ci_i32;
|
else -- compressed
|
else -- unaligned uncompressed
|
cmd_issue.data <= ci_illegal & ipb.rdata(33 downto 32) & '1' & ci_instr32;
|
issue_engine.valid <= (others => (ipb.avail(0) and ipb.avail(1)));
|
end if;
|
issue_engine.data <= '0' & (ipb.rdata(0)(17 downto 16) or ipb.rdata(1)(17 downto 16)) &
|
end if;
|
'0' & (ipb.rdata(0)(15 downto 00) & ipb.rdata(1)(15 downto 00));
|
|
|
-- store high half-word - we might need it for an unaligned uncompressed instruction --
|
|
if (execute_engine.state = DISPATCH) and (ipb.avail = '1') and (CPU_EXTENSION_RISCV_C = true) then
|
|
issue_engine.buf_nxt <= ipb.rdata(33 downto 32) & ipb.rdata(31 downto 16);
|
|
end if;
|
|
|
|
-- state machine --
|
|
if (ipb.avail = '1') then -- instruction data available?
|
|
|
|
if (issue_engine.realign = '0') then -- issue instruction if available
|
|
-- ------------------------------------------------------------
|
|
cmd_issue.valid <= '1';
|
|
if (issue_engine.align = '0') or (CPU_EXTENSION_RISCV_C = false) then -- begin check in LOW instruction half-word
|
|
if (execute_engine.state = DISPATCH) then -- ready to issue new command?
|
|
ipb.re <= '1';
|
|
if (ipb.rdata(1 downto 0) /= "11") and (CPU_EXTENSION_RISCV_C = true) then -- compressed
|
|
issue_engine.align_nxt <= '1';
|
|
end if;
|
|
end if;
|
|
else -- begin check in HIGH instruction half-word
|
|
if (execute_engine.state = DISPATCH) then -- ready to issue new command?
|
|
if (issue_engine.buf(1 downto 0) = "11") then -- uncompressed and unaligned
|
|
ipb.re <= '1';
|
|
else -- compressed - do not read from ipb here!
|
|
issue_engine.align_nxt <= '0';
|
|
end if;
|
|
end if;
|
|
end if;
|
|
|
|
else -- re-align input fifo and half-word buffer after a branch to an unaligned address
|
|
-- ------------------------------------------------------------
|
|
ipb.re <= '1';
|
|
issue_engine.realign_nxt <= '0';
|
|
end if;
|
end if;
|
|
|
end if;
|
end if;
|
end process issue_engine_fsm_comb;
|
end process issue_engine_fsm_comb;
|
|
|
-- 16-bit instructions: half-word select --
|
-- update IPB FIFOs (read-for-next)? --
|
ci_instr16 <= ipb.rdata(15 downto 0) when (issue_engine.align = '0') else issue_engine.buf(15 downto 0);
|
ipb.re <= issue_engine.valid when (execute_engine.state = DISPATCH) else "00";
|
|
|
|
|
-- Compressed Instructions Recoding -------------------------------------------------------
|
-- Compressed Instructions Decoding -------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
neorv32_cpu_decompressor_inst_true:
|
neorv32_cpu_decompressor_inst_true:
|
if (CPU_EXTENSION_RISCV_C = true) generate
|
if (CPU_EXTENSION_RISCV_C = true) generate
|
neorv32_cpu_decompressor_inst: neorv32_cpu_decompressor
|
neorv32_cpu_decompressor_inst: neorv32_cpu_decompressor
|
generic map (
|
generic map (
|
FPU_ENABLE => CPU_EXTENSION_RISCV_Zfinx -- floating-point instruction enabled
|
FPU_ENABLE => CPU_EXTENSION_RISCV_Zfinx -- floating-point instructions enabled
|
)
|
)
|
port map (
|
port map (
|
-- instruction input --
|
-- instruction input --
|
ci_instr16_i => ci_instr16, -- compressed instruction input
|
ci_instr16_i => issue_engine.ci_i16, -- compressed instruction input
|
-- instruction output --
|
-- instruction output --
|
ci_illegal_o => ci_illegal, -- is an illegal compressed instruction
|
ci_illegal_o => issue_engine.ci_ill, -- illegal compressed instruction
|
ci_instr32_o => ci_instr32 -- 32-bit decompressed instruction
|
ci_instr32_o => issue_engine.ci_i32 -- 32-bit decompressed instruction
|
);
|
);
|
end generate;
|
end generate;
|
|
|
neorv32_cpu_decompressor_inst_false:
|
neorv32_cpu_decompressor_inst_false:
|
if (CPU_EXTENSION_RISCV_C = false) generate
|
if (CPU_EXTENSION_RISCV_C = false) generate
|
ci_instr32 <= (others => '0');
|
issue_engine.ci_i32 <= (others => '0');
|
ci_illegal <= '0';
|
issue_engine.ci_ill <= '0';
|
end generate;
|
end generate;
|
|
|
|
-- 16-bit instructions: half-word select --
|
|
issue_engine.ci_i16 <= ipb.rdata(0)(15 downto 0) when (issue_engine.align = '0') else ipb.rdata(1)(15 downto 0);
|
|
|
|
|
-- ****************************************************************************************************************************
|
-- ****************************************************************************************************************************
|
-- Instruction Execution
|
-- Instruction Execution
|
-- ****************************************************************************************************************************
|
-- ****************************************************************************************************************************
|
|
|
-- Immediate Generator --------------------------------------------------------------------
|
-- Immediate Generator --------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
imm_gen: process(clk_i)
|
imm_gen: process(clk_i)
|
variable opcode_v : std_ulogic_vector(6 downto 0);
|
variable opcode_v : std_ulogic_vector(6 downto 0);
|
begin
|
begin
|
if rising_edge(clk_i) then
|
if rising_edge(clk_i) then
|
-- default: I-immediate: ALU-immediate, loads, jump-and-link with register
|
-- default: I-immediate: ALU-immediate, loads, jump-and-link with register
|
imm_o(31 downto 11) <= (others => execute_engine.i_reg(31)); -- sign extension
|
imm_o(31 downto 11) <= (others => execute_engine.i_reg(31)); -- sign extension
|
imm_o(10 downto 05) <= execute_engine.i_reg(30 downto 25);
|
imm_o(10 downto 05) <= execute_engine.i_reg(30 downto 25);
|
imm_o(04 downto 01) <= execute_engine.i_reg(24 downto 21);
|
imm_o(04 downto 01) <= execute_engine.i_reg(24 downto 21);
|
imm_o(00) <= execute_engine.i_reg(20);
|
imm_o(00) <= execute_engine.i_reg(20);
|
|
|
opcode_v := execute_engine.i_reg(instr_opcode_msb_c downto instr_opcode_lsb_c+2) & "11";
|
opcode_v := execute_engine.i_reg(instr_opcode_msb_c downto instr_opcode_lsb_c+2) & "11";
|
case opcode_v is -- save some bits here, the two LSBs are always "11" for rv32
|
case opcode_v is -- save some bits here, the two LSBs are always "11" for rv32
|
when opcode_store_c => -- S-immediate: store
|
when opcode_store_c => -- S-immediate: store
|
imm_o(31 downto 11) <= (others => execute_engine.i_reg(31)); -- sign extension
|
imm_o(31 downto 11) <= (others => execute_engine.i_reg(31)); -- sign extension
|
imm_o(10 downto 05) <= execute_engine.i_reg(30 downto 25);
|
imm_o(10 downto 05) <= execute_engine.i_reg(30 downto 25);
|
imm_o(04 downto 01) <= execute_engine.i_reg(11 downto 08);
|
imm_o(04 downto 01) <= execute_engine.i_reg(11 downto 08);
|
imm_o(00) <= execute_engine.i_reg(07);
|
imm_o(00) <= execute_engine.i_reg(07);
|
when opcode_branch_c => -- B-immediate: conditional branches
|
when opcode_branch_c => -- B-immediate: conditional branches
|
imm_o(31 downto 12) <= (others => execute_engine.i_reg(31)); -- sign extension
|
imm_o(31 downto 12) <= (others => execute_engine.i_reg(31)); -- sign extension
|
imm_o(11) <= execute_engine.i_reg(07);
|
imm_o(11) <= execute_engine.i_reg(07);
|
imm_o(10 downto 05) <= execute_engine.i_reg(30 downto 25);
|
imm_o(10 downto 05) <= execute_engine.i_reg(30 downto 25);
|
imm_o(04 downto 01) <= execute_engine.i_reg(11 downto 08);
|
imm_o(04 downto 01) <= execute_engine.i_reg(11 downto 08);
|
imm_o(00) <= '0';
|
imm_o(00) <= '0';
|
when opcode_lui_c | opcode_auipc_c => -- U-immediate: lui, auipc
|
when opcode_lui_c | opcode_auipc_c => -- U-immediate: lui, auipc
|
imm_o(31 downto 20) <= execute_engine.i_reg(31 downto 20);
|
imm_o(31 downto 20) <= execute_engine.i_reg(31 downto 20);
|
imm_o(19 downto 12) <= execute_engine.i_reg(19 downto 12);
|
imm_o(19 downto 12) <= execute_engine.i_reg(19 downto 12);
|
imm_o(11 downto 00) <= (others => '0');
|
imm_o(11 downto 00) <= (others => '0');
|
when opcode_jal_c => -- J-immediate: unconditional jumps
|
when opcode_jal_c => -- J-immediate: unconditional jumps
|
imm_o(31 downto 20) <= (others => execute_engine.i_reg(31)); -- sign extension
|
imm_o(31 downto 20) <= (others => execute_engine.i_reg(31)); -- sign extension
|
imm_o(19 downto 12) <= execute_engine.i_reg(19 downto 12);
|
imm_o(19 downto 12) <= execute_engine.i_reg(19 downto 12);
|
imm_o(11) <= execute_engine.i_reg(20);
|
imm_o(11) <= execute_engine.i_reg(20);
|
imm_o(10 downto 05) <= execute_engine.i_reg(30 downto 25);
|
imm_o(10 downto 05) <= execute_engine.i_reg(30 downto 25);
|
imm_o(04 downto 01) <= execute_engine.i_reg(24 downto 21);
|
imm_o(04 downto 01) <= execute_engine.i_reg(24 downto 21);
|
imm_o(00) <= '0';
|
imm_o(00) <= '0';
|
when opcode_atomic_c => -- atomic memory access and everything else
|
when opcode_atomic_c => -- atomic memory access and everything else
|
if (CPU_EXTENSION_RISCV_A = true) then
|
if (CPU_EXTENSION_RISCV_A = true) then
|
imm_o <= (others => '0'); -- effective address is addr = reg + 0 = reg
|
imm_o <= (others => '0'); -- effective address is addr = reg + 0 = reg
|
else
|
else
|
NULL; -- use default
|
NULL; -- use default
|
end if;
|
end if;
|
when others => -- I-immediate
|
when others => -- I-immediate
|
NULL; -- use default
|
NULL; -- use default
|
end case;
|
end case;
|
end if;
|
end if;
|
end process imm_gen;
|
end process imm_gen;
|
|
|
|
|
-- Branch Condition Check -----------------------------------------------------------------
|
-- Branch Condition Check -----------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
branch_check: process(execute_engine.i_reg, cmp_i)
|
branch_check: process(execute_engine.i_reg, cmp_i)
|
begin
|
begin
|
case execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) is
|
case execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) is
|
when funct3_beq_c => -- branch if equal
|
when funct3_beq_c => -- branch if equal
|
execute_engine.branch_taken <= cmp_i(cmp_equal_c);
|
execute_engine.branch_taken <= cmp_i(cmp_equal_c);
|
when funct3_bne_c => -- branch if not equal
|
when funct3_bne_c => -- branch if not equal
|
execute_engine.branch_taken <= not cmp_i(cmp_equal_c);
|
execute_engine.branch_taken <= not cmp_i(cmp_equal_c);
|
when funct3_blt_c | funct3_bltu_c => -- branch if less (signed/unsigned)
|
when funct3_blt_c | funct3_bltu_c => -- branch if less (signed/unsigned)
|
execute_engine.branch_taken <= cmp_i(cmp_less_c);
|
execute_engine.branch_taken <= cmp_i(cmp_less_c);
|
when others => -- branch if greater or equal (signed/unsigned), invalid funct3 are checked by illegal instr. logic
|
when others => -- branch if greater or equal (signed/unsigned), invalid funct3 are checked by illegal instr. logic
|
execute_engine.branch_taken <= not cmp_i(cmp_less_c);
|
execute_engine.branch_taken <= not cmp_i(cmp_less_c);
|
end case;
|
end case;
|
end process branch_check;
|
end process branch_check;
|
|
|
|
|
-- Execute Engine FSM Sync ----------------------------------------------------------------
|
-- Execute Engine FSM Sync ----------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
execute_engine_fsm_sync: process(rstn_i, clk_i)
|
execute_engine_fsm_sync: process(rstn_i, clk_i)
|
begin
|
begin
|
if (rstn_i = '0') then
|
if (rstn_i = '0') then
|
-- no dedicated reset required --
|
-- no dedicated reset required --
|
execute_engine.state_prev <= DISPATCH; -- actual reset value is not relevant
|
execute_engine.state_prev <= BRANCHED; -- actual reset value is not relevant
|
execute_engine.i_reg <= (others => def_rst_val_c);
|
execute_engine.i_reg <= (others => def_rst_val_c);
|
execute_engine.is_ci <= def_rst_val_c;
|
execute_engine.is_ci <= def_rst_val_c;
|
execute_engine.is_ici <= def_rst_val_c;
|
execute_engine.is_ici <= def_rst_val_c;
|
execute_engine.i_reg_last <= (others => def_rst_val_c);
|
execute_engine.i_reg_last <= (others => def_rst_val_c);
|
execute_engine.next_pc <= (others => def_rst_val_c);
|
execute_engine.next_pc <= (others => def_rst_val_c);
|
ctrl <= (others => def_rst_val_c);
|
ctrl <= (others => def_rst_val_c);
|
-- registers that DO require a specific RESET state --
|
-- registers that DO require a specific RESET state --
|
execute_engine.pc <= CPU_BOOT_ADDR(data_width_c-1 downto 2) & "00"; -- 32-bit aligned!
|
execute_engine.pc <= CPU_BOOT_ADDR(data_width_c-1 downto 2) & "00"; -- 32-bit aligned!
|
execute_engine.pc_last <= CPU_BOOT_ADDR(data_width_c-1 downto 2) & "00";
|
execute_engine.pc_last <= CPU_BOOT_ADDR(data_width_c-1 downto 2) & "00";
|
execute_engine.state <= DISPATCH;
|
execute_engine.state <= BRANCHED;
|
execute_engine.sleep <= '0';
|
execute_engine.sleep <= '0';
|
execute_engine.branched <= '1'; -- reset is a branch from "somewhere"
|
execute_engine.branched <= '1'; -- reset is a branch from "somewhere"
|
ctrl(ctrl_bus_rd_c) <= '0';
|
ctrl(ctrl_bus_rd_c) <= '0';
|
ctrl(ctrl_bus_wr_c) <= '0';
|
ctrl(ctrl_bus_wr_c) <= '0';
|
elsif rising_edge(clk_i) then
|
elsif rising_edge(clk_i) then
|
-- PC update --
|
-- PC update --
|
if (execute_engine.pc_we = '1') then
|
if (execute_engine.pc_we = '1') then
|
if (execute_engine.pc_mux_sel = '0') then
|
if (execute_engine.pc_mux_sel = '0') then
|
execute_engine.pc <= execute_engine.next_pc(data_width_c-1 downto 1) & '0'; -- normal (linear) increment OR trap enter/exit
|
execute_engine.pc <= execute_engine.next_pc(data_width_c-1 downto 1) & '0'; -- normal (linear) increment OR trap enter/exit
|
else
|
else
|
execute_engine.pc <= alu_add_i(data_width_c-1 downto 1) & '0'; -- jump/taken_branch
|
execute_engine.pc <= alu_add_i(data_width_c-1 downto 1) & '0'; -- jump/taken_branch
|
end if;
|
end if;
|
end if;
|
end if;
|
|
|
-- execute engine arbiter --
|
-- execute engine arbiter --
|
execute_engine.state <= execute_engine.state_nxt;
|
execute_engine.state <= execute_engine.state_nxt;
|
execute_engine.state_prev <= execute_engine.state;
|
execute_engine.state_prev <= execute_engine.state;
|
execute_engine.sleep <= execute_engine.sleep_nxt;
|
|
execute_engine.branched <= execute_engine.branched_nxt;
|
execute_engine.branched <= execute_engine.branched_nxt;
|
execute_engine.i_reg <= execute_engine.i_reg_nxt;
|
execute_engine.i_reg <= execute_engine.i_reg_nxt;
|
execute_engine.is_ci <= execute_engine.is_ci_nxt;
|
execute_engine.is_ci <= execute_engine.is_ci_nxt;
|
execute_engine.is_ici <= execute_engine.is_ici_nxt;
|
execute_engine.is_ici <= execute_engine.is_ici_nxt;
|
|
|
|
-- sleep mode --
|
|
if (CPU_EXTENSION_RISCV_DEBUG = true) and ((debug_ctrl.running = '1') or (csr.dcsr_step = '1')) then
|
|
execute_engine.sleep <= '0'; -- no sleep when in debug mode
|
|
else
|
|
execute_engine.sleep <= execute_engine.sleep_nxt;
|
|
end if;
|
|
|
-- PC & IR of "last executed" instruction for trap handling --
|
-- PC & IR of "last executed" instruction for trap handling --
|
if (execute_engine.state = EXECUTE) then
|
if (execute_engine.state = EXECUTE) then
|
execute_engine.pc_last <= execute_engine.pc;
|
execute_engine.pc_last <= execute_engine.pc;
|
execute_engine.i_reg_last <= execute_engine.i_reg;
|
execute_engine.i_reg_last <= execute_engine.i_reg;
|
end if;
|
end if;
|
|
|
-- next PC logic --
|
-- next PC logic --
|
case execute_engine.state is
|
case execute_engine.state is
|
when TRAP_ENTER => -- ENTERING trap environment
|
when TRAP_ENTER => -- ENTERING trap environment
|
if (trap_ctrl.cause(5) = '1') and (CPU_EXTENSION_RISCV_DEBUG = true) then -- trap cause: debug mode (re-)entry
|
if (trap_ctrl.cause(5) = '1') and (CPU_EXTENSION_RISCV_DEBUG = true) then -- trap cause: debug mode (re-)entry
|
execute_engine.next_pc <= CPU_DEBUG_ADDR; -- debug mode enter; start at "parking loop" <normal_entry>
|
execute_engine.next_pc <= CPU_DEBUG_ADDR; -- debug mode enter; start at "parking loop" <normal_entry>
|
elsif (debug_ctrl.running = '1') and (CPU_EXTENSION_RISCV_DEBUG = true) then -- any other exception INSIDE debug mode
|
elsif (debug_ctrl.running = '1') and (CPU_EXTENSION_RISCV_DEBUG = true) then -- any other exception INSIDE debug mode
|
execute_engine.next_pc <= std_ulogic_vector(unsigned(CPU_DEBUG_ADDR) + 4); -- start at "parking loop" <exception_entry>
|
execute_engine.next_pc <= std_ulogic_vector(unsigned(CPU_DEBUG_ADDR) + 4); -- start at "parking loop" <exception_entry>
|
else -- normal trapping
|
else -- normal trapping
|
execute_engine.next_pc <= csr.mtvec(data_width_c-1 downto 1) & '0'; -- trap enter
|
execute_engine.next_pc <= csr.mtvec(data_width_c-1 downto 2) & "00"; -- trap enter
|
end if;
|
end if;
|
when TRAP_EXIT => -- LEAVING trap environment
|
when TRAP_EXIT => -- LEAVING trap environment
|
if (CPU_EXTENSION_RISCV_DEBUG = false) or (debug_ctrl.running = '0') then -- normal end of trap
|
if (CPU_EXTENSION_RISCV_DEBUG = false) or (debug_ctrl.running = '0') then -- normal end of trap
|
execute_engine.next_pc <= csr.mepc(data_width_c-1 downto 1) & '0'; -- trap exit
|
execute_engine.next_pc <= csr.mepc(data_width_c-1 downto 1) & '0'; -- trap exit
|
else -- DEBUG MODE exiting
|
else -- DEBUG MODE exiting
|
execute_engine.next_pc <= csr.dpc(data_width_c-1 downto 1) & '0'; -- debug mode exit
|
execute_engine.next_pc <= csr.dpc(data_width_c-1 downto 1) & '0'; -- debug mode exit
|
end if;
|
end if;
|
when EXECUTE => -- NORMAL pc increment
|
when EXECUTE => -- NORMAL pc increment
|
execute_engine.next_pc <= std_ulogic_vector(unsigned(execute_engine.pc) + unsigned(execute_engine.next_pc_inc)); -- next linear PC
|
execute_engine.next_pc <= std_ulogic_vector(unsigned(execute_engine.pc) + unsigned(execute_engine.next_pc_inc)); -- next linear PC
|
when others =>
|
when others =>
|
NULL;
|
NULL;
|
end case;
|
end case;
|
|
|
-- main control bus buffer --
|
-- main control bus buffer --
|
ctrl <= ctrl_nxt;
|
ctrl <= ctrl_nxt;
|
end if;
|
end if;
|
end process execute_engine_fsm_sync;
|
end process execute_engine_fsm_sync;
|
|
|
|
|
-- PC increment for next linear instruction (+2 for compressed instr., +4 otherwise) --
|
-- PC increment for next linear instruction (+2 for compressed instr., +4 otherwise) --
|
execute_engine.next_pc_inc(data_width_c-1 downto 4) <= (others => '0');
|
execute_engine.next_pc_inc(data_width_c-1 downto 4) <= (others => '0');
|
execute_engine.next_pc_inc(3 downto 0) <= x"4" when ((execute_engine.is_ci = '0') or (CPU_EXTENSION_RISCV_C = false)) else x"2";
|
execute_engine.next_pc_inc(3 downto 0) <= x"4" when ((execute_engine.is_ci = '0') or (CPU_EXTENSION_RISCV_C = false)) else x"2";
|
|
|
-- PC output --
|
-- PC output --
|
curr_pc_o <= execute_engine.pc(data_width_c-1 downto 1) & '0'; -- current PC
|
curr_pc_o <= execute_engine.pc(data_width_c-1 downto 1) & '0'; -- current PC
|
next_pc_o <= execute_engine.next_pc(data_width_c-1 downto 1) & '0'; -- next PC
|
next_pc_o <= execute_engine.next_pc(data_width_c-1 downto 1) & '0'; -- next PC
|
|
|
-- CSR access address --
|
|
csr.addr <= execute_engine.i_reg(instr_csr_id_msb_c downto instr_csr_id_lsb_c);
|
|
|
|
|
|
-- CPU Control Bus Output -----------------------------------------------------------------
|
-- CPU Control Bus Output -----------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
ctrl_output: process(ctrl, fetch_engine, trap_ctrl, execute_engine, csr, debug_ctrl)
|
ctrl_output: process(ctrl, fetch_engine, trap_ctrl, execute_engine, csr, debug_ctrl)
|
begin
|
begin
|
-- signals from execute engine --
|
-- signals from execute engine --
|
ctrl_o <= ctrl;
|
ctrl_o <= ctrl;
|
-- prevent commits if illegal instruction --
|
-- prevent commits if illegal instruction --
|
ctrl_o(ctrl_rf_wb_en_c) <= ctrl(ctrl_rf_wb_en_c) and (not trap_ctrl.exc_buf(exc_iillegal_c));
|
ctrl_o(ctrl_rf_wb_en_c) <= ctrl(ctrl_rf_wb_en_c) and (not trap_ctrl.exc_buf(exc_iillegal_c));
|
ctrl_o(ctrl_bus_rd_c) <= ctrl(ctrl_bus_rd_c) and (not trap_ctrl.exc_buf(exc_iillegal_c));
|
ctrl_o(ctrl_bus_rd_c) <= ctrl(ctrl_bus_rd_c) and (not trap_ctrl.exc_buf(exc_iillegal_c));
|
ctrl_o(ctrl_bus_wr_c) <= ctrl(ctrl_bus_wr_c) and (not trap_ctrl.exc_buf(exc_iillegal_c));
|
ctrl_o(ctrl_bus_wr_c) <= ctrl(ctrl_bus_wr_c) and (not trap_ctrl.exc_buf(exc_iillegal_c));
|
-- current effective privilege level --
|
-- current effective privilege level --
|
ctrl_o(ctrl_priv_mode_c) <= csr.privilege_eff;
|
ctrl_o(ctrl_priv_mode_c) <= csr.privilege_eff;
|
-- register addresses --
|
-- register addresses --
|
ctrl_o(ctrl_rf_rs1_adr4_c downto ctrl_rf_rs1_adr0_c) <= execute_engine.i_reg(instr_rs1_msb_c downto instr_rs1_lsb_c);
|
ctrl_o(ctrl_rf_rs1_adr4_c downto ctrl_rf_rs1_adr0_c) <= execute_engine.i_reg(instr_rs1_msb_c downto instr_rs1_lsb_c);
|
ctrl_o(ctrl_rf_rs2_adr4_c downto ctrl_rf_rs2_adr0_c) <= execute_engine.i_reg(instr_rs2_msb_c downto instr_rs2_lsb_c);
|
ctrl_o(ctrl_rf_rs2_adr4_c downto ctrl_rf_rs2_adr0_c) <= execute_engine.i_reg(instr_rs2_msb_c downto instr_rs2_lsb_c);
|
ctrl_o(ctrl_rf_rd_adr4_c downto ctrl_rf_rd_adr0_c) <= execute_engine.i_reg(instr_rd_msb_c downto instr_rd_lsb_c);
|
ctrl_o(ctrl_rf_rd_adr4_c downto ctrl_rf_rd_adr0_c) <= execute_engine.i_reg(instr_rd_msb_c downto instr_rd_lsb_c);
|
-- instruction fetch request --
|
-- instruction fetch request --
|
ctrl_o(ctrl_bus_if_c) <= fetch_engine.bus_ir;
|
ctrl_o(ctrl_bus_if_c) <= fetch_engine.bus_if;
|
-- memory access size / sign --
|
-- memory access size / sign --
|
ctrl_o(ctrl_bus_unsigned_c) <= execute_engine.i_reg(instr_funct3_msb_c); -- unsigned LOAD (LBU, LHU)
|
ctrl_o(ctrl_bus_unsigned_c) <= execute_engine.i_reg(instr_funct3_msb_c); -- unsigned LOAD (LBU, LHU)
|
ctrl_o(ctrl_bus_size_msb_c downto ctrl_bus_size_lsb_c) <= execute_engine.i_reg(instr_funct3_lsb_c+1 downto instr_funct3_lsb_c); -- mem transfer size
|
ctrl_o(ctrl_bus_size_msb_c downto ctrl_bus_size_lsb_c) <= execute_engine.i_reg(instr_funct3_lsb_c+1 downto instr_funct3_lsb_c); -- mem transfer size
|
-- alu.shifter --
|
|
ctrl_o(ctrl_alu_shift_dir_c) <= execute_engine.i_reg(instr_funct3_msb_c); -- shift direction (left/right)
|
|
ctrl_o(ctrl_alu_shift_ar_c) <= execute_engine.i_reg(30); -- is arithmetic shift
|
|
-- instruction's function blocks (for co-processors) --
|
-- instruction's function blocks (for co-processors) --
|
ctrl_o(ctrl_ir_opcode7_6_c downto ctrl_ir_opcode7_0_c) <= execute_engine.i_reg(instr_opcode_msb_c downto instr_opcode_lsb_c);
|
ctrl_o(ctrl_ir_opcode7_6_c downto ctrl_ir_opcode7_0_c) <= execute_engine.i_reg(instr_opcode_msb_c downto instr_opcode_lsb_c);
|
ctrl_o(ctrl_ir_funct12_11_c downto ctrl_ir_funct12_0_c) <= execute_engine.i_reg(instr_funct12_msb_c downto instr_funct12_lsb_c);
|
ctrl_o(ctrl_ir_funct12_11_c downto ctrl_ir_funct12_0_c) <= execute_engine.i_reg(instr_funct12_msb_c downto instr_funct12_lsb_c);
|
ctrl_o(ctrl_ir_funct3_2_c downto ctrl_ir_funct3_0_c) <= execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c);
|
ctrl_o(ctrl_ir_funct3_2_c downto ctrl_ir_funct3_0_c) <= execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c);
|
-- cpu status --
|
-- cpu status --
|
ctrl_o(ctrl_sleep_c) <= execute_engine.sleep; -- cpu is in sleep mode
|
ctrl_o(ctrl_sleep_c) <= execute_engine.sleep; -- cpu is in sleep mode
|
ctrl_o(ctrl_trap_c) <= trap_ctrl.env_start_ack; -- cpu is starting a trap handler
|
ctrl_o(ctrl_trap_c) <= trap_ctrl.env_start_ack; -- cpu is starting a trap handler
|
ctrl_o(ctrl_debug_running_c) <= debug_ctrl.running; -- cpu is currently in debug mode
|
ctrl_o(ctrl_debug_running_c) <= debug_ctrl.running; -- cpu is currently in debug mode
|
-- FPU rounding mode --
|
-- FPU rounding mode --
|
ctrl_o(ctrl_alu_frm2_c downto ctrl_alu_frm0_c) <= csr.frm;
|
ctrl_o(ctrl_alu_frm2_c downto ctrl_alu_frm0_c) <= csr.frm;
|
end process ctrl_output;
|
end process ctrl_output;
|
|
|
|
|
-- Decoding Helper Logic ------------------------------------------------------------------
|
-- Decoding Helper Logic ------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
decode_helper: process(execute_engine)
|
decode_helper: process(execute_engine)
|
begin
|
begin
|
-- defaults --
|
-- defaults --
|
decode_aux.is_a_lr <= '0';
|
decode_aux.is_a_lr <= '0';
|
decode_aux.is_a_sc <= '0';
|
decode_aux.is_a_sc <= '0';
|
decode_aux.is_f_op <= '0';
|
decode_aux.is_f_op <= '0';
|
decode_aux.is_m_mul <= '0';
|
decode_aux.is_m_mul <= '0';
|
decode_aux.is_m_div <= '0';
|
decode_aux.is_m_div <= '0';
|
decode_aux.is_b_imm <= '0';
|
decode_aux.is_b_imm <= '0';
|
decode_aux.is_b_reg <= '0';
|
decode_aux.is_b_reg <= '0';
|
decode_aux.rs1_zero <= '0';
|
decode_aux.rs1_zero <= '0';
|
decode_aux.rd_zero <= '0';
|
decode_aux.rd_zero <= '0';
|
|
|
-- is atomic load-reservate/store-conditional? --
|
-- is atomic load-reservate/store-conditional? --
|
if (CPU_EXTENSION_RISCV_A = true) and (execute_engine.i_reg(instr_opcode_lsb_c+2) = '1') then -- valid atomic sub-opcode
|
if (CPU_EXTENSION_RISCV_A = true) and (execute_engine.i_reg(instr_opcode_lsb_c+2) = '1') then -- valid atomic sub-opcode
|
decode_aux.is_a_lr <= not execute_engine.i_reg(instr_funct5_lsb_c);
|
decode_aux.is_a_lr <= not execute_engine.i_reg(instr_funct5_lsb_c);
|
decode_aux.is_a_sc <= execute_engine.i_reg(instr_funct5_lsb_c);
|
decode_aux.is_a_sc <= execute_engine.i_reg(instr_funct5_lsb_c);
|
end if;
|
end if;
|
|
|
-- is BITMANIP instruction? --
|
-- is BITMANIP instruction? --
|
-- pretty complex as we have to extract this from the ALU/ALUI instruction space --
|
-- pretty complex as we have to extract this from the ALU/ALUI instruction space --
|
if (CPU_EXTENSION_RISCV_B = true) then -- BITMANIP implemented at all?
|
if (CPU_EXTENSION_RISCV_B = true) then -- BITMANIP implemented at all?
|
-- immediate operation --
|
-- immediate operation --
|
if ((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0110000") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "001") and
|
if ((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0110000") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "001") and
|
(
|
(
|
(execute_engine.i_reg(instr_funct12_lsb_c+4 downto instr_funct12_lsb_c) = "00000") or -- CLZ
|
(execute_engine.i_reg(instr_funct12_lsb_c+4 downto instr_funct12_lsb_c) = "00000") or -- CLZ
|
(execute_engine.i_reg(instr_funct12_lsb_c+4 downto instr_funct12_lsb_c) = "00001") or -- CTZ
|
(execute_engine.i_reg(instr_funct12_lsb_c+4 downto instr_funct12_lsb_c) = "00001") or -- CTZ
|
(execute_engine.i_reg(instr_funct12_lsb_c+4 downto instr_funct12_lsb_c) = "00010") or -- CPOP
|
(execute_engine.i_reg(instr_funct12_lsb_c+4 downto instr_funct12_lsb_c) = "00010") or -- CPOP
|
(execute_engine.i_reg(instr_funct12_lsb_c+4 downto instr_funct12_lsb_c) = "00100") or -- SEXT.B
|
(execute_engine.i_reg(instr_funct12_lsb_c+4 downto instr_funct12_lsb_c) = "00100") or -- SEXT.B
|
(execute_engine.i_reg(instr_funct12_lsb_c+4 downto instr_funct12_lsb_c) = "00101") -- SEXT.H
|
(execute_engine.i_reg(instr_funct12_lsb_c+4 downto instr_funct12_lsb_c) = "00101") -- SEXT.H
|
)
|
)
|
) or
|
) or
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0110000") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "101")) or -- RORI
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0110000") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "101")) or -- RORI
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0010100") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "101") and (execute_engine.i_reg(instr_funct12_lsb_c+4 downto instr_funct12_lsb_c) = "00111")) or -- ORCB
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0010100") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "101") and (execute_engine.i_reg(instr_funct12_lsb_c+4 downto instr_funct12_lsb_c) = "00111")) or -- ORCB
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0110100") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "101")) or -- REV8
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0110100") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "101")) or -- REV8
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0100100") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "001")) or -- BCLRI
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0100100") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "001")) or -- BCLRI
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0100100") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "101")) or -- BEXTI
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0100100") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "101")) or -- BEXTI
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0110100") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "001")) or -- BINVI
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0110100") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "001")) or -- BINVI
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0010100") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "001")) then -- BSETI
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0010100") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "001")) then -- BSETI
|
decode_aux.is_b_imm <= '1';
|
decode_aux.is_b_imm <= '1';
|
end if;
|
end if;
|
-- register operation --
|
-- register operation --
|
if ((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0110000") and (execute_engine.i_reg(instr_funct3_msb_c-1 downto instr_funct3_lsb_c) = "01")) or -- ROR / ROL
|
if ((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0110000") and (execute_engine.i_reg(instr_funct3_msb_c-1 downto instr_funct3_lsb_c) = "01")) or -- ROR / ROL
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0000101") and (execute_engine.i_reg(instr_funct3_msb_c) = '1')) or -- MIN[U] / MAX[U]
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0000101") and (execute_engine.i_reg(instr_funct3_msb_c) = '1')) or -- MIN[U] / MAX[U]
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0000100") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "100")) or -- ZEXTH
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0000100") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "100")) or -- ZEXTH
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0100100") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "001")) or -- BCLR
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0100100") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "001")) or -- BCLR
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0100100") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "101")) or -- BEXT
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0100100") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "101")) or -- BEXT
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0110100") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "001")) or -- BINV
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0110100") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "001")) or -- BINV
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0010100") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "001")) or -- BSET
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0010100") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "001")) or -- BSET
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0000101") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "001")) or -- CLMUL
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0000101") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "001")) or -- CLMUL
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0000101") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "011")) or -- CLMULH
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0000101") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "011")) or -- CLMULH
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0000101") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "010")) or -- CLMULR
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0000101") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "010")) or -- CLMULR
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0100000") and
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0100000") and
|
(
|
(
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "111") or -- ANDN
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "111") or -- ANDN
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "110") or -- ORN
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "110") or -- ORN
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "100") -- XORN
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "100") -- XORN
|
)
|
)
|
) or
|
) or
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0010000") and
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0010000") and
|
(
|
(
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "010") or -- SH1ADD
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "010") or -- SH1ADD
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "100") or -- SH2ADD
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "100") or -- SH2ADD
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "110") -- SH3ADD
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "110") -- SH3ADD
|
)
|
)
|
) then
|
) then
|
decode_aux.is_b_reg <= '1';
|
decode_aux.is_b_reg <= '1';
|
end if;
|
end if;
|
end if;
|
end if;
|
|
|
-- floating-point operations (Zfinx) --
|
-- floating-point operations (Zfinx) --
|
if (CPU_EXTENSION_RISCV_Zfinx = true) then -- FPU implemented at all?
|
if (CPU_EXTENSION_RISCV_Zfinx = true) then -- FPU implemented at all?
|
if ((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c+3) = "0000")) or -- FADD.S / FSUB.S
|
if ((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c+3) = "0000")) or -- FADD.S / FSUB.S
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c+2) = "00010")) or -- FMUL.S
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c+2) = "00010")) or -- FMUL.S
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c+2) = "11100") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "001")) or -- FCLASS.S
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c+2) = "11100") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "001")) or -- FCLASS.S
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c+2) = "00100") and (execute_engine.i_reg(instr_funct3_msb_c) = '0')) or -- FSGNJ[N/X].S
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c+2) = "00100") and (execute_engine.i_reg(instr_funct3_msb_c) = '0')) or -- FSGNJ[N/X].S
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c+2) = "00101") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_msb_c-1) = "00")) or -- FMIN.S / FMAX.S
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c+2) = "00101") and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_msb_c-1) = "00")) or -- FMIN.S / FMAX.S
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c+2) = "10100") and (execute_engine.i_reg(instr_funct3_msb_c) = '0')) or -- FEQ.S / FLT.S / FLE.S
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c+2) = "10100") and (execute_engine.i_reg(instr_funct3_msb_c) = '0')) or -- FEQ.S / FLT.S / FLE.S
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c+2) = "11010") and (execute_engine.i_reg(instr_funct12_lsb_c+4 downto instr_funct12_lsb_c+1) = "0000")) or -- FCVT.S.W*
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c+2) = "11010") and (execute_engine.i_reg(instr_funct12_lsb_c+4 downto instr_funct12_lsb_c+1) = "0000")) or -- FCVT.S.W*
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c+2) = "11000") and (execute_engine.i_reg(instr_funct12_lsb_c+4 downto instr_funct12_lsb_c+1) = "0000")) then -- FCVT.W*.S
|
((execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c+2) = "11000") and (execute_engine.i_reg(instr_funct12_lsb_c+4 downto instr_funct12_lsb_c+1) = "0000")) then -- FCVT.W*.S
|
decode_aux.is_f_op <= '1';
|
decode_aux.is_f_op <= '1';
|
end if;
|
end if;
|
end if;
|
end if;
|
|
|
-- integer MUL (M/Zmmul) / DIV (M) operation --
|
-- integer MUL (M/Zmmul) / DIV (M) operation --
|
if (execute_engine.i_reg(instr_opcode_lsb_c+5) = opcode_alu_c(5)) and (execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0000001") then
|
if (execute_engine.i_reg(instr_opcode_lsb_c+5) = opcode_alu_c(5)) and (execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0000001") then
|
if ((CPU_EXTENSION_RISCV_M = true) or (CPU_EXTENSION_RISCV_Zmmul = true)) and (execute_engine.i_reg(instr_funct3_msb_c) = '0') then
|
if ((CPU_EXTENSION_RISCV_M = true) or (CPU_EXTENSION_RISCV_Zmmul = true)) and (execute_engine.i_reg(instr_funct3_msb_c) = '0') then
|
decode_aux.is_m_mul <= '1';
|
decode_aux.is_m_mul <= '1';
|
end if;
|
end if;
|
if (CPU_EXTENSION_RISCV_M = true) and (execute_engine.i_reg(instr_funct3_msb_c) = '1') then
|
if (CPU_EXTENSION_RISCV_M = true) and (execute_engine.i_reg(instr_funct3_msb_c) = '1') then
|
decode_aux.is_m_div <= '1';
|
decode_aux.is_m_div <= '1';
|
end if;
|
end if;
|
end if;
|
end if;
|
|
|
-- register/uimm5 checks --
|
-- register/uimm5 checks --
|
decode_aux.rs1_zero <= not or_reduce_f(execute_engine.i_reg(instr_rs1_msb_c downto instr_rs1_lsb_c));
|
if (execute_engine.i_reg(instr_rs1_msb_c downto instr_rs1_lsb_c) = "00000") then
|
decode_aux.rd_zero <= not or_reduce_f(execute_engine.i_reg(instr_rd_msb_c downto instr_rd_lsb_c));
|
decode_aux.rs1_zero <= '1';
|
|
else
|
|
decode_aux.rs1_zero <= '0';
|
|
end if;
|
|
if (execute_engine.i_reg(instr_rd_msb_c downto instr_rd_lsb_c) = "00000") then
|
|
decode_aux.rd_zero <= '1';
|
|
else
|
|
decode_aux.rd_zero <= '0';
|
|
end if;
|
end process decode_helper;
|
end process decode_helper;
|
|
|
|
-- CSR access address --
|
|
csr.addr <= execute_engine.i_reg(instr_imm12_msb_c downto instr_imm12_lsb_c);
|
|
|
|
|
-- Execute Engine FSM Comb ----------------------------------------------------------------
|
-- Execute Engine FSM Comb ----------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
execute_engine_fsm_comb: process(execute_engine, debug_ctrl, trap_ctrl, decode_aux, fetch_engine, cmd_issue,
|
execute_engine_fsm_comb: process(execute_engine, debug_ctrl, trap_ctrl, decode_aux, fetch_engine, issue_engine,
|
csr, ctrl, alu_idone_i, bus_d_wait_i, excl_state_i)
|
csr, ctrl, alu_idone_i, bus_d_wait_i, excl_state_i)
|
variable opcode_v : std_ulogic_vector(6 downto 0);
|
|
begin
|
begin
|
-- arbiter defaults --
|
-- arbiter defaults --
|
execute_engine.state_nxt <= execute_engine.state;
|
execute_engine.state_nxt <= execute_engine.state;
|
execute_engine.i_reg_nxt <= execute_engine.i_reg;
|
execute_engine.i_reg_nxt <= execute_engine.i_reg;
|
execute_engine.is_ci_nxt <= execute_engine.is_ci;
|
execute_engine.is_ci_nxt <= execute_engine.is_ci;
|
execute_engine.is_ici_nxt <= '0';
|
execute_engine.is_ici_nxt <= '0';
|
execute_engine.sleep_nxt <= execute_engine.sleep;
|
execute_engine.sleep_nxt <= execute_engine.sleep;
|
execute_engine.branched_nxt <= execute_engine.branched;
|
execute_engine.branched_nxt <= execute_engine.branched;
|
--
|
--
|
execute_engine.pc_mux_sel <= '0';
|
execute_engine.pc_mux_sel <= '0';
|
execute_engine.pc_we <= '0';
|
execute_engine.pc_we <= '0';
|
|
|
-- instruction dispatch --
|
-- instruction dispatch --
|
fetch_engine.reset <= '0';
|
fetch_engine.reset <= '0';
|
|
|
-- trap environment control --
|
-- trap environment control --
|
trap_ctrl.env_start_ack <= '0';
|
trap_ctrl.env_start_ack <= '0';
|
trap_ctrl.env_end <= '0';
|
trap_ctrl.env_end <= '0';
|
|
|
-- leave debug mode --
|
-- leave debug mode --
|
debug_ctrl.dret <= '0';
|
debug_ctrl.dret <= '0';
|
|
|
-- exception trigger --
|
-- exception trigger --
|
trap_ctrl.instr_be <= '0';
|
trap_ctrl.instr_be <= '0';
|
trap_ctrl.instr_ma <= '0';
|
trap_ctrl.instr_ma <= '0';
|
trap_ctrl.env_call <= '0';
|
trap_ctrl.env_call <= '0';
|
trap_ctrl.break_point <= '0';
|
trap_ctrl.break_point <= '0';
|
|
|
-- CSR access --
|
-- CSR access --
|
csr.we_nxt <= '0';
|
csr.we_nxt <= '0';
|
|
csr.re_nxt <= '0';
|
|
|
-- CONTROL DEFAULTS --
|
-- CONTROL DEFAULTS --
|
ctrl_nxt <= (others => '0'); -- default: all off
|
ctrl_nxt <= (others => '0'); -- default: all off
|
ctrl_nxt(ctrl_alu_op2_c downto ctrl_alu_op0_c) <= alu_op_add_c; -- default ALU operation: ADD
|
ctrl_nxt(ctrl_alu_op2_c downto ctrl_alu_op0_c) <= alu_op_add_c; -- default ALU operation: ADD
|
ctrl_nxt(ctrl_rf_mux1_c downto ctrl_rf_mux0_c) <= rf_mux_alu_c; -- default RF input: ALU
|
ctrl_nxt(ctrl_rf_mux1_c downto ctrl_rf_mux0_c) <= rf_mux_alu_c; -- default RF input: ALU
|
-- ALU sign control --
|
-- ALU sign control --
|
if (execute_engine.i_reg(instr_opcode_lsb_c+4) = '1') then -- ALU ops
|
if (execute_engine.i_reg(instr_opcode_lsb_c+4) = '1') then -- ALU ops
|
ctrl_nxt(ctrl_alu_unsigned_c) <= execute_engine.i_reg(instr_funct3_lsb_c+0); -- unsigned ALU operation? (SLTIU, SLTU)
|
ctrl_nxt(ctrl_alu_unsigned_c) <= execute_engine.i_reg(instr_funct3_lsb_c+0); -- unsigned ALU operation? (SLTIU, SLTU)
|
else -- branches
|
else -- branches
|
ctrl_nxt(ctrl_alu_unsigned_c) <= execute_engine.i_reg(instr_funct3_lsb_c+1); -- unsigned branches? (BLTU, BGEU)
|
ctrl_nxt(ctrl_alu_unsigned_c) <= execute_engine.i_reg(instr_funct3_lsb_c+1); -- unsigned branches? (BLTU, BGEU)
|
end if;
|
end if;
|
-- atomic store-conditional instruction (evaluate lock status) --
|
-- atomic store-conditional instruction (evaluate lock status) --
|
ctrl_nxt(ctrl_bus_ch_lock_c) <= decode_aux.is_a_sc;
|
ctrl_nxt(ctrl_bus_ch_lock_c) <= decode_aux.is_a_sc;
|
|
|
|
|
-- state machine --
|
-- state machine --
|
case execute_engine.state is
|
case execute_engine.state is
|
|
|
when DISPATCH => -- Get new command from instruction issue engine
|
when DISPATCH => -- Get new command from instruction issue engine
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
-- PC update --
|
-- PC & IR update --
|
execute_engine.pc_mux_sel <= '0'; -- linear next PC
|
execute_engine.pc_mux_sel <= '0'; -- linear next PC
|
-- IR update --
|
execute_engine.i_reg_nxt <= issue_engine.data(31 downto 0);
|
execute_engine.is_ci_nxt <= cmd_issue.data(32); -- flag to indicate a de-compressed instruction
|
execute_engine.is_ci_nxt <= issue_engine.data(32); -- this is a de-compressed instruction
|
execute_engine.i_reg_nxt <= cmd_issue.data(31 downto 0);
|
execute_engine.is_ici_nxt <= issue_engine.data(35); -- illegal compressed instruction
|
--
|
--
|
if (cmd_issue.valid = '1') then -- instruction available?
|
if (issue_engine.valid(0) = '1') or (issue_engine.valid(1) = '1') then -- instruction available?
|
-- PC update --
|
-- PC update --
|
execute_engine.branched_nxt <= '0';
|
execute_engine.branched_nxt <= '0';
|
execute_engine.pc_we <= not execute_engine.branched; -- update PC with linear next_pc if there was no actual branch
|
execute_engine.pc_we <= not execute_engine.branched; -- update PC with linear next_pc if there was no actual branch
|
-- IR update - exceptions --
|
-- IR update - exceptions --
|
if (CPU_EXTENSION_RISCV_C = false) then
|
trap_ctrl.instr_ma <= issue_engine.data(33) and (not bool_to_ulogic_f(CPU_EXTENSION_RISCV_C)); -- misaligned instruction fetch (if C disabled)
|
trap_ctrl.instr_ma <= cmd_issue.data(33); -- misaligned instruction fetch address, if C disabled
|
trap_ctrl.instr_be <= issue_engine.data(34); -- bus access fault during instruction fetch
|
end if;
|
|
trap_ctrl.instr_be <= cmd_issue.data(34); -- bus access fault during instruction fetch
|
|
execute_engine.is_ici_nxt <= cmd_issue.data(35); -- invalid decompressed instruction
|
|
-- any reason to go to trap state? --
|
-- any reason to go to trap state? --
|
if (execute_engine.sleep = '1') or -- enter sleep state
|
if (execute_engine.sleep = '1') or -- enter sleep state
|
(trap_ctrl.exc_fire = '1') or -- exception during LAST instruction (e.g. illegal instruction)
|
(trap_ctrl.exc_fire = '1') or -- exception during LAST instruction (e.g. illegal instruction)
|
(trap_ctrl.env_start = '1') or -- pending trap (IRQ or exception)
|
(trap_ctrl.env_start = '1') or -- pending trap (IRQ or exception)
|
((cmd_issue.data(33) = '1') and (CPU_EXTENSION_RISCV_C = false)) or -- misaligned instruction fetch address (if C disabled)
|
((issue_engine.data(33) = '1') and (CPU_EXTENSION_RISCV_C = false)) or -- misaligned instruction fetch address (if C disabled)
|
(cmd_issue.data(34) = '1') then -- bus access fault during instruction fetch
|
(issue_engine.data(34) = '1') then -- bus access fault during instruction fetch
|
execute_engine.state_nxt <= TRAP_ENTER;
|
execute_engine.state_nxt <= TRAP_ENTER;
|
else
|
else
|
execute_engine.state_nxt <= EXECUTE;
|
execute_engine.state_nxt <= EXECUTE;
|
end if;
|
end if;
|
end if;
|
end if;
|
|
|
|
|
when TRAP_ENTER => -- Start trap environment - get trap vector (depc or epc), stay here for sleep mode
|
when TRAP_ENTER => -- Start trap environment - get trap vector, stay here for sleep mode
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
if (trap_ctrl.env_start = '1') then -- trap triggered?
|
if (trap_ctrl.env_start = '1') then -- trap triggered?
|
trap_ctrl.env_start_ack <= '1';
|
trap_ctrl.env_start_ack <= '1';
|
execute_engine.state_nxt <= TRAP_EXECUTE;
|
execute_engine.state_nxt <= TRAP_EXECUTE;
|
end if;
|
end if;
|
|
|
|
|
when TRAP_EXIT => -- Return from trap environment - get xEPC
|
when TRAP_EXIT => -- Return from trap environment - get xEPC
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
trap_ctrl.env_end <= '1';
|
trap_ctrl.env_end <= '1';
|
execute_engine.state_nxt <= TRAP_EXECUTE;
|
execute_engine.state_nxt <= TRAP_EXECUTE;
|
|
|
|
|
when TRAP_EXECUTE => -- Process trap environment -> jump to xTVEC / return from trap environment -> jump to xEPC
|
when TRAP_EXECUTE => -- Process trap environment
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
execute_engine.pc_mux_sel <= '0'; -- next_PC
|
execute_engine.pc_mux_sel <= '0'; -- next_PC (or xEPC / trap vector)
|
fetch_engine.reset <= '1';
|
fetch_engine.reset <= '1';
|
execute_engine.pc_we <= '1';
|
execute_engine.pc_we <= '1';
|
execute_engine.sleep_nxt <= '0'; -- disable sleep mode
|
execute_engine.sleep_nxt <= '0'; -- disable sleep mode
|
execute_engine.state_nxt <= DISPATCH;
|
execute_engine.state_nxt <= BRANCHED;
|
|
|
|
|
when EXECUTE => -- Decode and execute instruction (control has to be here for exactly 1 cycle in any case!)
|
when EXECUTE => -- Decode and execute instruction (control has to be here for exactly 1 cycle in any case!)
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
opcode_v := execute_engine.i_reg(instr_opcode_msb_c downto instr_opcode_lsb_c+2) & "11"; -- save some bits here, LSBs are always 11 for rv32
|
case execute_engine.i_reg(instr_opcode_msb_c downto instr_opcode_lsb_c) is
|
case opcode_v is
|
|
|
|
when opcode_alu_c | opcode_alui_c => -- (register/immediate) ALU operation
|
when opcode_alu_c | opcode_alui_c => -- (register/immediate) ALU operation
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
ctrl_nxt(ctrl_alu_opb_mux_c) <= not execute_engine.i_reg(instr_opcode_msb_c-1); -- use IMM as ALU.OPB for immediate operations
|
ctrl_nxt(ctrl_alu_opb_mux_c) <= not execute_engine.i_reg(instr_opcode_msb_c-1); -- use IMM as ALU.OPB for immediate operations
|
|
|
-- ALU core operation --
|
-- ALU core operation --
|
case execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) is -- actual ALU.logic operation (re-coding)
|
case execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) is -- actual ALU.logic operation (re-coding)
|
when funct3_subadd_c => -- ADD(I)/SUB
|
when funct3_subadd_c => -- ADD(I)/SUB
|
if ((execute_engine.i_reg(instr_opcode_msb_c-1) = '1') and (execute_engine.i_reg(instr_funct7_msb_c-1) = '1')) then -- not an immediate op and funct7.6 set => SUB
|
if ((execute_engine.i_reg(instr_opcode_msb_c-1) = '1') and (execute_engine.i_reg(instr_funct7_msb_c-1) = '1')) then -- not an immediate op and funct7.6 set => SUB
|
ctrl_nxt(ctrl_alu_op2_c downto ctrl_alu_op0_c) <= alu_op_sub_c;
|
ctrl_nxt(ctrl_alu_op2_c downto ctrl_alu_op0_c) <= alu_op_sub_c;
|
else
|
else
|
ctrl_nxt(ctrl_alu_op2_c downto ctrl_alu_op0_c) <= alu_op_add_c;
|
ctrl_nxt(ctrl_alu_op2_c downto ctrl_alu_op0_c) <= alu_op_add_c;
|
end if;
|
end if;
|
when funct3_slt_c | funct3_sltu_c => -- SLT(I), SLTU(I)
|
when funct3_slt_c | funct3_sltu_c => -- SLT(I), SLTU(I)
|
ctrl_nxt(ctrl_alu_op2_c downto ctrl_alu_op0_c) <= alu_op_slt_c;
|
ctrl_nxt(ctrl_alu_op2_c downto ctrl_alu_op0_c) <= alu_op_slt_c;
|
when funct3_xor_c => -- XOR(I)
|
when funct3_xor_c => -- XOR(I)
|
ctrl_nxt(ctrl_alu_op2_c downto ctrl_alu_op0_c) <= alu_op_xor_c;
|
ctrl_nxt(ctrl_alu_op2_c downto ctrl_alu_op0_c) <= alu_op_xor_c;
|
when funct3_or_c => -- OR(I)
|
when funct3_or_c => -- OR(I)
|
ctrl_nxt(ctrl_alu_op2_c downto ctrl_alu_op0_c) <= alu_op_or_c;
|
ctrl_nxt(ctrl_alu_op2_c downto ctrl_alu_op0_c) <= alu_op_or_c;
|
when others => -- AND(I), multi-cycle / co-processor operations
|
when others => -- AND(I), multi-cycle / co-processor operations
|
ctrl_nxt(ctrl_alu_op2_c downto ctrl_alu_op0_c) <= alu_op_and_c;
|
ctrl_nxt(ctrl_alu_op2_c downto ctrl_alu_op0_c) <= alu_op_and_c;
|
end case;
|
end case;
|
|
|
-- co-processor MULDIV operation (multi-cycle) --
|
-- co-processor MULDIV operation (multi-cycle) --
|
if ((CPU_EXTENSION_RISCV_M = true) and ((decode_aux.is_m_mul = '1') or (decode_aux.is_m_div = '1'))) or -- MUL/DIV
|
if ((CPU_EXTENSION_RISCV_M = true) and ((decode_aux.is_m_mul = '1') or (decode_aux.is_m_div = '1'))) or -- MUL/DIV
|
((CPU_EXTENSION_RISCV_Zmmul = true) and (decode_aux.is_m_mul = '1')) then -- MUL
|
((CPU_EXTENSION_RISCV_Zmmul = true) and (decode_aux.is_m_mul = '1')) then -- MUL
|
ctrl_nxt(ctrl_cp_id_msb_c downto ctrl_cp_id_lsb_c) <= cp_sel_muldiv_c; -- trigger MULDIV CP
|
ctrl_nxt(ctrl_cp_trig7_c downto ctrl_cp_trig0_c) <= cp_sel_muldiv_c; -- trigger MULDIV CP
|
execute_engine.state_nxt <= ALU_WAIT;
|
execute_engine.state_nxt <= ALU_WAIT;
|
-- co-processor BIT-MANIPULATION operation (multi-cycle) --
|
-- co-processor BIT-MANIPULATION operation (multi-cycle) --
|
elsif (CPU_EXTENSION_RISCV_B = true) and
|
elsif (CPU_EXTENSION_RISCV_B = true) and
|
(((execute_engine.i_reg(instr_opcode_lsb_c+5) = opcode_alu_c(5)) and (decode_aux.is_b_reg = '1')) or -- register operation
|
(((execute_engine.i_reg(instr_opcode_lsb_c+5) = opcode_alu_c(5)) and (decode_aux.is_b_reg = '1')) or -- register operation
|
((execute_engine.i_reg(instr_opcode_lsb_c+5) = opcode_alui_c(5)) and (decode_aux.is_b_imm = '1'))) then -- immediate operation
|
((execute_engine.i_reg(instr_opcode_lsb_c+5) = opcode_alui_c(5)) and (decode_aux.is_b_imm = '1'))) then -- immediate operation
|
ctrl_nxt(ctrl_cp_id_msb_c downto ctrl_cp_id_lsb_c) <= cp_sel_bitmanip_c; -- trigger BITMANIP CP
|
ctrl_nxt(ctrl_cp_trig7_c downto ctrl_cp_trig0_c) <= cp_sel_bitmanip_c; -- trigger BITMANIP CP
|
execute_engine.state_nxt <= ALU_WAIT;
|
execute_engine.state_nxt <= ALU_WAIT;
|
-- co-processor SHIFT operation (multi-cycle) --
|
-- co-processor SHIFT operation (multi-cycle) --
|
elsif (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_sll_c) or
|
elsif (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_sll_c) or
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_sr_c) then
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_sr_c) then
|
ctrl_nxt(ctrl_cp_id_msb_c downto ctrl_cp_id_lsb_c) <= cp_sel_shifter_c; -- trigger SHIFTER CP
|
ctrl_nxt(ctrl_cp_trig7_c downto ctrl_cp_trig0_c) <= cp_sel_shifter_c; -- trigger SHIFTER CP
|
execute_engine.state_nxt <= ALU_WAIT;
|
execute_engine.state_nxt <= ALU_WAIT;
|
-- ALU CORE operation (single-cycle) --
|
-- ALU CORE operation (single-cycle) --
|
else
|
else
|
ctrl_nxt(ctrl_rf_wb_en_c) <= '1'; -- valid RF write-back
|
ctrl_nxt(ctrl_rf_wb_en_c) <= '1'; -- valid RF write-back
|
execute_engine.state_nxt <= DISPATCH;
|
execute_engine.state_nxt <= DISPATCH;
|
end if;
|
end if;
|
|
|
|
|
when opcode_lui_c | opcode_auipc_c => -- load upper immediate / add upper immediate to PC
|
when opcode_lui_c | opcode_auipc_c => -- load upper immediate / add upper immediate to PC
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
ctrl_nxt(ctrl_alu_opa_mux_c) <= '1'; -- ALU.OPA = PC (for AUIPC only)
|
ctrl_nxt(ctrl_alu_opa_mux_c) <= '1'; -- ALU.OPA = PC (for AUIPC only)
|
ctrl_nxt(ctrl_alu_opb_mux_c) <= '1'; -- use IMM as ALU.OPB
|
ctrl_nxt(ctrl_alu_opb_mux_c) <= '1'; -- use IMM as ALU.OPB
|
if (execute_engine.i_reg(instr_opcode_lsb_c+5) = opcode_lui_c(5)) then -- LUI
|
if (execute_engine.i_reg(instr_opcode_lsb_c+5) = opcode_lui_c(5)) then -- LUI
|
ctrl_nxt(ctrl_alu_op2_c downto ctrl_alu_op0_c) <= alu_op_movb_c; -- actual ALU operation = MOVB
|
ctrl_nxt(ctrl_alu_op2_c downto ctrl_alu_op0_c) <= alu_op_movb_c; -- actual ALU operation = MOVB
|
else -- AUIPC
|
else -- AUIPC
|
ctrl_nxt(ctrl_alu_op2_c downto ctrl_alu_op0_c) <= alu_op_add_c; -- actual ALU operation = ADD
|
ctrl_nxt(ctrl_alu_op2_c downto ctrl_alu_op0_c) <= alu_op_add_c; -- actual ALU operation = ADD
|
end if;
|
end if;
|
ctrl_nxt(ctrl_rf_wb_en_c) <= '1'; -- valid RF write-back
|
ctrl_nxt(ctrl_rf_wb_en_c) <= '1'; -- valid RF write-back
|
execute_engine.state_nxt <= DISPATCH;
|
execute_engine.state_nxt <= DISPATCH;
|
|
|
|
|
when opcode_load_c | opcode_store_c | opcode_atomic_c => -- load/store / atomic memory access
|
when opcode_load_c | opcode_store_c | opcode_atomic_c => -- load/store / atomic memory access
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
ctrl_nxt(ctrl_alu_opb_mux_c) <= '1'; -- use IMM as ALU.OPB
|
ctrl_nxt(ctrl_alu_opb_mux_c) <= '1'; -- use IMM as ALU.OPB
|
ctrl_nxt(ctrl_bus_mo_we_c) <= '1'; -- write to MAR and MDO (MDO only relevant for store)
|
ctrl_nxt(ctrl_bus_mo_we_c) <= '1'; -- write to MAR and MDO (MDO only relevant for store)
|
execute_engine.state_nxt <= LOADSTORE_0;
|
execute_engine.state_nxt <= LOADSTORE_0;
|
|
|
|
|
when opcode_branch_c | opcode_jal_c | opcode_jalr_c => -- branch / jump and link (with register)
|
when opcode_branch_c | opcode_jal_c | opcode_jalr_c => -- branch / jump and link (with register)
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
if (execute_engine.i_reg(instr_opcode_lsb_c+3 downto instr_opcode_lsb_c+2) = opcode_jalr_c(3 downto 2)) then -- JALR
|
if (execute_engine.i_reg(instr_opcode_lsb_c+3 downto instr_opcode_lsb_c+2) = opcode_jalr_c(3 downto 2)) then -- JALR
|
ctrl_nxt(ctrl_alu_opa_mux_c) <= '0'; -- use RS1 as ALU.OPA (branch target address base)
|
ctrl_nxt(ctrl_alu_opa_mux_c) <= '0'; -- use RS1 as ALU.OPA (branch target address base)
|
else -- JAL
|
else -- JAL
|
ctrl_nxt(ctrl_alu_opa_mux_c) <= '1'; -- use PC as ALU.OPA (branch target address base)
|
ctrl_nxt(ctrl_alu_opa_mux_c) <= '1'; -- use PC as ALU.OPA (branch target address base)
|
end if;
|
end if;
|
ctrl_nxt(ctrl_alu_opb_mux_c) <= '1'; -- use IMM as ALU.OPB (branch target address offset)
|
ctrl_nxt(ctrl_alu_opb_mux_c) <= '1'; -- use IMM as ALU.OPB (branch target address offset)
|
execute_engine.state_nxt <= BRANCH;
|
execute_engine.state_nxt <= BRANCH;
|
|
|
|
|
when opcode_fence_c => -- fence operations
|
when opcode_fence_c => -- fence operations
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
if (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_fence_c) then -- FENCE
|
if (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c+1) = funct3_fence_c(2 downto 1)) then -- FENCE / FENCE.I
|
ctrl_nxt(ctrl_bus_fence_c) <= '1';
|
ctrl_nxt(ctrl_bus_fence_c) <= not execute_engine.i_reg(instr_funct3_lsb_c); -- FENCE
|
execute_engine.state_nxt <= DISPATCH;
|
ctrl_nxt(ctrl_bus_fencei_c) <= execute_engine.i_reg(instr_funct3_lsb_c) and bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zifencei); -- FENCE.I
|
elsif (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_fencei_c) and (CPU_EXTENSION_RISCV_Zifencei = true) then -- FENCE.I
|
|
ctrl_nxt(ctrl_bus_fencei_c) <= '1';
|
|
execute_engine.branched_nxt <= '1'; -- this is an actual branch
|
|
execute_engine.state_nxt <= TRAP_EXECUTE; -- use TRAP_EXECUTE to "modify" PC (PC <= PC)
|
|
else -- illegal fence instruction
|
|
execute_engine.state_nxt <= DISPATCH;
|
|
end if;
|
end if;
|
|
execute_engine.state_nxt <= TRAP_EXECUTE; -- use TRAP_EXECUTE to "modify" PC (PC <= PC)
|
|
|
|
|
when opcode_fop_c => -- floating-point operations
|
when opcode_fop_c => -- floating-point operations
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
if (CPU_EXTENSION_RISCV_Zfinx = true) then
|
if (CPU_EXTENSION_RISCV_Zfinx = true) then
|
ctrl_nxt(ctrl_cp_id_msb_c downto ctrl_cp_id_lsb_c) <= cp_sel_fpu_c; -- trigger FPU CP
|
ctrl_nxt(ctrl_cp_trig7_c downto ctrl_cp_trig0_c) <= cp_sel_fpu_c; -- trigger FPU CP
|
execute_engine.state_nxt <= ALU_WAIT;
|
execute_engine.state_nxt <= ALU_WAIT;
|
else
|
else
|
execute_engine.state_nxt <= DISPATCH;
|
execute_engine.state_nxt <= DISPATCH;
|
end if;
|
end if;
|
|
|
|
|
when opcode_cust0_c => -- CFU: custom RISC-V instructions (CUSTOM0 OPCODE space)
|
when opcode_cust0_c => -- CFU: custom RISC-V instructions (CUSTOM0 OPCODE space)
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
if (CPU_EXTENSION_RISCV_Zxcfu = true) then
|
if (CPU_EXTENSION_RISCV_Zxcfu = true) then
|
ctrl_nxt(ctrl_cp_id_msb_c downto ctrl_cp_id_lsb_c) <= cp_sel_cfu_c; -- trigger CFU CP
|
ctrl_nxt(ctrl_cp_trig7_c downto ctrl_cp_trig0_c) <= cp_sel_cfu_c; -- trigger CFU CP
|
execute_engine.state_nxt <= ALU_WAIT;
|
execute_engine.state_nxt <= ALU_WAIT;
|
else
|
else
|
execute_engine.state_nxt <= DISPATCH;
|
execute_engine.state_nxt <= DISPATCH;
|
end if;
|
end if;
|
|
|
|
|
when others => -- system/csr access OR illegal opcode
|
when opcode_system_c => -- environment/csr access
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
|
csr.re_nxt <= '1'; -- always read CSR, only relevant for CSR access
|
if (CPU_EXTENSION_RISCV_Zicsr = true) then
|
if (CPU_EXTENSION_RISCV_Zicsr = true) then
|
if (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_env_c) then -- system/environment
|
execute_engine.state_nxt <= SYSTEM;
|
execute_engine.state_nxt <= SYS_ENV;
|
|
else -- CSR access
|
|
execute_engine.state_nxt <= CSR_ACCESS;
|
|
end if;
|
|
else
|
else
|
execute_engine.state_nxt <= DISPATCH;
|
execute_engine.state_nxt <= DISPATCH;
|
end if;
|
end if;
|
|
|
end case;
|
|
|
|
|
|
when SYS_ENV => -- system environment operation
|
when others => -- illegal opcode
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
-- MRET / DRET --
|
execute_engine.state_nxt <= DISPATCH;
|
if (execute_engine.i_reg(instr_funct12_msb_c downto instr_funct12_lsb_c) = funct12_mret_c) then
|
|
execute_engine.state_nxt <= TRAP_EXIT; -- mret
|
end case; -- /EXECUTE
|
elsif (execute_engine.i_reg(instr_funct12_msb_c downto instr_funct12_lsb_c) = funct12_dret_c) and
|
|
(CPU_EXTENSION_RISCV_DEBUG = true) then
|
|
debug_ctrl.dret <= '1';
|
|
execute_engine.state_nxt <= TRAP_EXIT; -- dret
|
|
else
|
|
execute_engine.state_nxt <= DISPATCH; -- default
|
|
end if;
|
|
-- ECALL / EBREAK --
|
|
if ((execute_engine.i_reg(instr_funct12_msb_c downto instr_funct12_lsb_c+1) = funct12_ecall_c(11 downto 1))) then
|
|
if (execute_engine.i_reg(instr_funct12_lsb_c) = funct12_ecall_c(0)) then
|
|
trap_ctrl.env_call <= '1'; -- ecall
|
|
else
|
|
trap_ctrl.break_point <= '1'; -- ebreak
|
|
end if;
|
|
end if;
|
|
-- WFI --
|
|
if (execute_engine.i_reg(instr_funct12_msb_c downto instr_funct12_lsb_c) = funct12_wfi_c) and
|
|
((CPU_EXTENSION_RISCV_DEBUG = false) or ((debug_ctrl.running = '0') and (csr.dcsr_step = '0'))) then
|
|
execute_engine.sleep_nxt <= '1'; -- not executed (NOP) when in debug-mode or during single-stepping
|
|
end if;
|
|
|
|
|
|
when CSR_ACCESS => -- read & write status and control register (CSR) - no read/write if illegal instruction
|
when SYSTEM => -- system environment operation
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
-- CSR write access [invalid CSR instructions are already checked by the illegal instruction logic] --
|
ctrl_nxt(ctrl_rf_mux1_c downto ctrl_rf_mux0_c) <= rf_mux_csr_c; -- only relevant for CSR access
|
if (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_csrrw_c) or
|
execute_engine.state_nxt <= DISPATCH; -- default
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_csrrwi_c) or -- CSRRW(I); always write CSR
|
if (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_env_c) and -- ENVIRONMENT
|
(decode_aux.rs1_zero = '0') then -- CSRRS(I) / CSRRC(I): write CSR if rs1/imm5 is NOT zero
|
(trap_ctrl.exc_buf(exc_iillegal_c) = '0') then -- and NOT already identified as illegal instruction
|
|
case execute_engine.i_reg(instr_funct12_msb_c downto instr_funct12_lsb_c) is
|
|
when funct12_ecall_c => trap_ctrl.env_call <= '1'; -- ecall
|
|
when funct12_ebreak_c => trap_ctrl.break_point <= '1'; -- ebreak
|
|
when funct12_mret_c => execute_engine.state_nxt <= TRAP_EXIT; -- mret
|
|
when funct12_dret_c => execute_engine.state_nxt <= TRAP_EXIT; debug_ctrl.dret <= '1'; -- dret
|
|
when others => execute_engine.sleep_nxt <= '1'; -- "funct12_wfi_c" - wfi/sleep
|
|
end case;
|
|
else -- CSR ACCESS - there will be no state change if illegal instruction
|
|
if (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_csrrw_c) or -- CSRRW: always write CSR
|
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_csrrwi_c) or -- CSRRWI: always write CSR
|
|
(decode_aux.rs1_zero = '0') then -- CSRR(S/C)(I): write CSR if rs1/imm5 is NOT zero
|
csr.we_nxt <= '1';
|
csr.we_nxt <= '1';
|
end if;
|
end if;
|
-- register file write back --
|
|
ctrl_nxt(ctrl_rf_mux1_c downto ctrl_rf_mux0_c) <= rf_mux_csr_c;
|
|
ctrl_nxt(ctrl_rf_wb_en_c) <= '1'; -- valid RF write-back
|
ctrl_nxt(ctrl_rf_wb_en_c) <= '1'; -- valid RF write-back
|
execute_engine.state_nxt <= DISPATCH;
|
end if;
|
|
|
|
|
when ALU_WAIT => -- wait for multi-cycle ALU operation (ALU co-processor) to finish
|
when ALU_WAIT => -- wait for multi-cycle ALU operation (ALU co-processor) to finish
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
ctrl_nxt(ctrl_alu_op2_c downto ctrl_alu_op0_c) <= alu_op_cp_c;
|
ctrl_nxt(ctrl_alu_op2_c downto ctrl_alu_op0_c) <= alu_op_cp_c;
|
-- wait for completion or abort on illegal instruction exception (the co-processor will also terminate operations)
|
-- wait for completion or abort on illegal instruction exception (the co-processor will also terminate operations)
|
if (alu_idone_i = '1') or (trap_ctrl.exc_buf(exc_iillegal_c) = '1') then
|
if (alu_idone_i = '1') or (trap_ctrl.exc_buf(exc_iillegal_c) = '1') then
|
ctrl_nxt(ctrl_rf_wb_en_c) <= '1'; -- valid RF write-back (won't happen in case of an illegal instruction)
|
ctrl_nxt(ctrl_rf_wb_en_c) <= '1'; -- valid RF write-back (won't happen in case of an illegal instruction)
|
execute_engine.state_nxt <= DISPATCH;
|
execute_engine.state_nxt <= DISPATCH;
|
end if;
|
end if;
|
|
|
|
|
when BRANCH => -- update PC for taken branches and jumps
|
when BRANCH => -- update PC on taken branches and jumps
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
-- get and store return address (only relevant for jump-and-link operations) --
|
-- get and store return address (only relevant for jump-and-link operations) --
|
ctrl_nxt(ctrl_rf_mux1_c downto ctrl_rf_mux0_c) <= rf_mux_npc_c; -- next PC
|
ctrl_nxt(ctrl_rf_mux1_c downto ctrl_rf_mux0_c) <= rf_mux_npc_c; -- next PC
|
ctrl_nxt(ctrl_rf_wb_en_c) <= execute_engine.i_reg(instr_opcode_lsb_c+2); -- valid RF write-back? (is jump-and-link?)
|
ctrl_nxt(ctrl_rf_wb_en_c) <= execute_engine.i_reg(instr_opcode_lsb_c+2); -- valid RF write-back? (is jump-and-link?)
|
-- destination address --
|
-- destination address --
|
execute_engine.pc_mux_sel <= '1'; -- PC <= alu.add = branch/jump destination
|
execute_engine.pc_mux_sel <= '1'; -- PC <= alu.add = branch/jump destination
|
|
execute_engine.pc_we <= '1'; -- update PC with destination; will be overridden again in DISPATCH if branch not taken
|
if (execute_engine.i_reg(instr_opcode_lsb_c+2) = '1') or (execute_engine.branch_taken = '1') then -- JAL/JALR or taken branch
|
if (execute_engine.i_reg(instr_opcode_lsb_c+2) = '1') or (execute_engine.branch_taken = '1') then -- JAL/JALR or taken branch
|
-- no need to check for illegal instructions here; the branch condition evaluation circuit will not set "branch_taken" if funct3 is invalid
|
fetch_engine.reset <= '1'; -- reset instruction fetch starting at modified PC
|
execute_engine.pc_we <= '1'; -- update PC
|
execute_engine.state_nxt <= BRANCHED;
|
execute_engine.branched_nxt <= '1'; -- this is an actual branch
|
else
|
fetch_engine.reset <= '1'; -- trigger new instruction fetch from modified PC
|
execute_engine.state_nxt <= DISPATCH;
|
end if;
|
end if;
|
|
|
|
|
|
when BRANCHED => -- delay cycle to wait for reset of pipeline front-end
|
|
-- ------------------------------------------------------------
|
|
execute_engine.branched_nxt <= '1'; -- this is an actual branch
|
execute_engine.state_nxt <= DISPATCH;
|
execute_engine.state_nxt <= DISPATCH;
|
|
|
|
|
when LOADSTORE_0 => -- trigger memory request
|
when LOADSTORE_0 => -- trigger memory request
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
ctrl_nxt(ctrl_bus_lock_c) <= decode_aux.is_a_lr; -- atomic.LR: set lock
|
|
if (execute_engine.i_reg(instr_opcode_msb_c-1) = '0') or (decode_aux.is_a_lr = '1') then -- normal load or atomic load-reservate
|
if (execute_engine.i_reg(instr_opcode_msb_c-1) = '0') or (decode_aux.is_a_lr = '1') then -- normal load or atomic load-reservate
|
ctrl_nxt(ctrl_bus_rd_c) <= '1'; -- read request
|
ctrl_nxt(ctrl_bus_rd_c) <= '1'; -- bus read request
|
else -- store
|
elsif (decode_aux.is_a_sc = '0') or (excl_state_i = '1') then -- normal store request or atomic store-conditional with lock still OK
|
if (decode_aux.is_a_sc = '0') or (CPU_EXTENSION_RISCV_A = false) then -- (normal) write request
|
ctrl_nxt(ctrl_bus_wr_c) <= '1'; -- bus write request
|
ctrl_nxt(ctrl_bus_wr_c) <= '1';
|
|
else -- evaluate lock state
|
|
ctrl_nxt(ctrl_bus_wr_c) <= excl_state_i; -- write request if lock is still ok
|
|
end if;
|
|
end if;
|
end if;
|
|
ctrl_nxt(ctrl_bus_lock_c) <= decode_aux.is_a_lr; -- atomic load-reservate: set lock
|
execute_engine.state_nxt <= LOADSTORE_1;
|
execute_engine.state_nxt <= LOADSTORE_1;
|
|
|
|
|
when LOADSTORE_1 => -- memory access latency
|
when LOADSTORE_1 => -- memory access latency
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
ctrl_nxt(ctrl_bus_mi_we_c) <= '1'; -- write input data to MDI (only relevant for LOADs)
|
ctrl_nxt(ctrl_bus_mi_we_c) <= '1'; -- write input data to MDI (only relevant for load and SC.W operations)
|
execute_engine.state_nxt <= LOADSTORE_2;
|
execute_engine.state_nxt <= LOADSTORE_2;
|
|
|
|
|
when LOADSTORE_2 => -- wait for bus transaction to finish
|
when LOADSTORE_2 => -- wait for bus transaction to finish
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
ctrl_nxt(ctrl_bus_mi_we_c) <= '1'; -- keep writing input data to MDI (only relevant for load (and SC.W) operations)
|
ctrl_nxt(ctrl_bus_mi_we_c) <= '1'; -- keep writing input data to MDI (only relevant for load and SC.W operations)
|
ctrl_nxt(ctrl_rf_mux1_c downto ctrl_rf_mux0_c) <= rf_mux_mem_c; -- memory read data
|
ctrl_nxt(ctrl_rf_mux1_c downto ctrl_rf_mux0_c) <= rf_mux_mem_c; -- memory read data
|
-- wait for memory response --
|
-- wait for memory response --
|
if (trap_ctrl.env_start = '1') and (trap_ctrl.cause(6 downto 5) = "00") then -- abort if SYNC EXCEPTION (from bus or illegal cmd) / no IRQs and NOT DEBUG-MODE-related
|
if (trap_ctrl.env_start = '1') and (trap_ctrl.cause(6 downto 5) = "00") then -- abort if SYNC EXCEPTION (from bus or illegal cmd) / no IRQs and NOT DEBUG-MODE-related
|
execute_engine.state_nxt <= DISPATCH;
|
execute_engine.state_nxt <= DISPATCH;
|
elsif (bus_d_wait_i = '0') then -- wait for bus to finish transaction
|
elsif (bus_d_wait_i = '0') then -- wait for bus to finish transaction
|
-- data write-back --
|
-- data write-back --
|
if (execute_engine.i_reg(instr_opcode_msb_c-1) = '0') or -- normal load
|
if (execute_engine.i_reg(instr_opcode_msb_c-1) = '0') or -- normal load
|
(decode_aux.is_a_lr = '1') or -- atomic load-reservate
|
(decode_aux.is_a_lr = '1') or -- atomic load-reservate
|
(decode_aux.is_a_sc = '1') then -- atomic store-conditional
|
(decode_aux.is_a_sc = '1') then -- atomic store-conditional
|
ctrl_nxt(ctrl_rf_wb_en_c) <= '1';
|
ctrl_nxt(ctrl_rf_wb_en_c) <= '1';
|
end if;
|
end if;
|
-- remove atomic lock if this is NOT the LR.W instruction used to SET the lock --
|
-- remove atomic lock if this is NOT the LR.W instruction used to SET the lock --
|
if (decode_aux.is_a_lr = '0') then -- execute and evaluate atomic store-conditional
|
if (decode_aux.is_a_lr = '0') then -- execute and evaluate atomic store-conditional
|
ctrl_nxt(ctrl_bus_de_lock_c) <= '1';
|
ctrl_nxt(ctrl_bus_de_lock_c) <= '1';
|
end if;
|
end if;
|
execute_engine.state_nxt <= DISPATCH;
|
execute_engine.state_nxt <= DISPATCH;
|
end if;
|
end if;
|
|
|
|
|
when others => -- undefined
|
when others => -- undefined
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
execute_engine.state_nxt <= DISPATCH;
|
execute_engine.state_nxt <= DISPATCH;
|
|
|
end case;
|
end case;
|
end process execute_engine_fsm_comb;
|
end process execute_engine_fsm_comb;
|
|
|
|
|
-- ****************************************************************************************************************************
|
-- ****************************************************************************************************************************
|
-- Illegal Instruction and CSR Access Check
|
-- Illegal Instruction and CSR Access Check
|
-- ****************************************************************************************************************************
|
-- ****************************************************************************************************************************
|
|
|
-- CSR Access Check -----------------------------------------------------------------------
|
-- CSR Access Check -----------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
csr_access_check: process(execute_engine.i_reg, decode_aux, csr, debug_ctrl)
|
csr_access_check: process(execute_engine.i_reg, decode_aux, csr, debug_ctrl)
|
variable csr_wacc_v : std_ulogic; -- actual CSR write
|
variable csr_wacc_v : std_ulogic; -- actual CSR write
|
begin
|
begin
|
-- is this CSR instruction really going to write to a CSR? --
|
-- is this CSR instruction really going to write to a CSR? --
|
if (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_csrrw_c) or -- always write CSR
|
if (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_csrrw_c) or -- always write CSR
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_csrrwi_c) or -- always write CSR
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_csrrwi_c) or -- always write CSR
|
(decode_aux.rs1_zero = '0') then -- clear/set: write CSR if rs1/imm5 is NOT zero
|
(decode_aux.rs1_zero = '0') then -- clear/set: write CSR if rs1/imm5 is NOT zero
|
csr_wacc_v := '1';
|
csr_wacc_v := '1';
|
else
|
else
|
csr_wacc_v := '0';
|
csr_wacc_v := '0';
|
end if;
|
end if;
|
|
|
-- check CSR access --
|
-- check CSR access --
|
csr_acc_valid <= '0'; -- default: invalid access
|
csr_acc_valid <= '0'; -- default: invalid access
|
case csr.addr is
|
case csr.addr is
|
|
|
-- floating-point CSRs --
|
-- floating-point CSRs --
|
when csr_fflags_c | csr_frm_c | csr_fcsr_c =>
|
when csr_fflags_c | csr_frm_c | csr_fcsr_c =>
|
csr_acc_valid <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zfinx); -- full access for everyone if FPU implemented
|
csr_acc_valid <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zfinx); -- full access for everyone if FPU implemented
|
|
|
-- machine trap setup/handling & counters --
|
-- machine trap setup/handling & counters --
|
when csr_mstatus_c | csr_mstatush_c | csr_misa_c | csr_mie_c | csr_mtvec_c | csr_mscratch_c | csr_mepc_c | csr_mcause_c | csr_mip_c | csr_mtval_c |
|
when csr_mstatus_c | csr_mstatush_c | csr_misa_c | csr_mie_c | csr_mtvec_c | csr_mscratch_c | csr_mepc_c | csr_mcause_c | csr_mip_c | csr_mtval_c |
|
csr_mcycle_c | csr_mcycleh_c | csr_minstret_c | csr_minstreth_c | csr_mcountinhibit_c =>
|
csr_mcycle_c | csr_mcycleh_c | csr_minstret_c | csr_minstreth_c | csr_mcountinhibit_c =>
|
-- NOTE: MISA and MTVAL are read-only in the NEORV32 but we do not cause an exception here for compatibility.
|
-- NOTE: MISA and MTVAL are read-only in the NEORV32 but we do not cause an exception here for compatibility.
|
-- Machine-level code should read-back those CSRs after writing them to realize they are read-only.
|
-- Machine-level code should read-back those CSRs after writing them to realize they are read-only.
|
csr_acc_valid <= csr.privilege_eff; -- M-mode only
|
csr_acc_valid <= csr.privilege_eff; -- M-mode only
|
|
|
-- machine information registers & NEORV32-specific registers, read-only --
|
-- machine information registers & NEORV32-specific registers, read-only --
|
when csr_mvendorid_c | csr_marchid_c | csr_mimpid_c | csr_mhartid_c | csr_mconfigptr_c | csr_mxisa_c =>
|
when csr_mvendorid_c | csr_marchid_c | csr_mimpid_c | csr_mhartid_c | csr_mconfigptr_c | csr_mxisa_c =>
|
csr_acc_valid <= (not csr_wacc_v) and csr.privilege_eff; -- M-mode only, read-only
|
csr_acc_valid <= (not csr_wacc_v) and csr.privilege_eff; -- M-mode only, read-only
|
|
|
-- user-mode registers --
|
-- user-mode registers --
|
when csr_mcounteren_c | csr_menvcfg_c | csr_menvcfgh_c =>
|
when csr_mcounteren_c | csr_menvcfg_c | csr_menvcfgh_c =>
|
csr_acc_valid <= csr.privilege_eff and bool_to_ulogic_f(CPU_EXTENSION_RISCV_U);
|
csr_acc_valid <= csr.privilege_eff and bool_to_ulogic_f(CPU_EXTENSION_RISCV_U);
|
|
|
-- physical memory protection (PMP) --
|
-- physical memory protection (PMP) --
|
when csr_pmpaddr0_c | csr_pmpaddr1_c | csr_pmpaddr2_c | csr_pmpaddr3_c | csr_pmpaddr4_c | csr_pmpaddr5_c | csr_pmpaddr6_c | csr_pmpaddr7_c | -- address
|
when csr_pmpaddr0_c | csr_pmpaddr1_c | csr_pmpaddr2_c | csr_pmpaddr3_c | csr_pmpaddr4_c | csr_pmpaddr5_c | csr_pmpaddr6_c | csr_pmpaddr7_c | -- address
|
csr_pmpaddr8_c | csr_pmpaddr9_c | csr_pmpaddr10_c | csr_pmpaddr11_c | csr_pmpaddr12_c | csr_pmpaddr13_c | csr_pmpaddr14_c | csr_pmpaddr15_c |
|
csr_pmpaddr8_c | csr_pmpaddr9_c | csr_pmpaddr10_c | csr_pmpaddr11_c | csr_pmpaddr12_c | csr_pmpaddr13_c | csr_pmpaddr14_c | csr_pmpaddr15_c |
|
csr_pmpcfg0_c | csr_pmpcfg1_c | csr_pmpcfg2_c | csr_pmpcfg3_c => -- configuration
|
csr_pmpcfg0_c | csr_pmpcfg1_c | csr_pmpcfg2_c | csr_pmpcfg3_c => -- configuration
|
csr_acc_valid <= csr.privilege_eff and bool_to_ulogic_f(boolean(PMP_NUM_REGIONS > 0)); -- M-mode only
|
csr_acc_valid <= csr.privilege_eff and bool_to_ulogic_f(boolean(PMP_NUM_REGIONS > 0)); -- M-mode only
|
|
|
-- machine hardware performance monitors (MHPM) --
|
-- machine hardware performance monitors (MHPM) --
|
when csr_mhpmcounter3_c | csr_mhpmcounter4_c | csr_mhpmcounter5_c | csr_mhpmcounter6_c | csr_mhpmcounter7_c | csr_mhpmcounter8_c | -- counter LOW
|
when csr_mhpmcounter3_c | csr_mhpmcounter4_c | csr_mhpmcounter5_c | csr_mhpmcounter6_c | csr_mhpmcounter7_c | csr_mhpmcounter8_c | -- counter LOW
|
csr_mhpmcounter9_c | csr_mhpmcounter10_c | csr_mhpmcounter11_c | csr_mhpmcounter12_c | csr_mhpmcounter13_c | csr_mhpmcounter14_c |
|
csr_mhpmcounter9_c | csr_mhpmcounter10_c | csr_mhpmcounter11_c | csr_mhpmcounter12_c | csr_mhpmcounter13_c | csr_mhpmcounter14_c |
|
csr_mhpmcounter15_c | csr_mhpmcounter16_c | csr_mhpmcounter17_c | csr_mhpmcounter18_c | csr_mhpmcounter19_c | csr_mhpmcounter20_c |
|
csr_mhpmcounter15_c | csr_mhpmcounter16_c | csr_mhpmcounter17_c | csr_mhpmcounter18_c | csr_mhpmcounter19_c | csr_mhpmcounter20_c |
|
csr_mhpmcounter21_c | csr_mhpmcounter22_c | csr_mhpmcounter23_c | csr_mhpmcounter24_c | csr_mhpmcounter25_c | csr_mhpmcounter26_c |
|
csr_mhpmcounter21_c | csr_mhpmcounter22_c | csr_mhpmcounter23_c | csr_mhpmcounter24_c | csr_mhpmcounter25_c | csr_mhpmcounter26_c |
|
csr_mhpmcounter27_c | csr_mhpmcounter28_c | csr_mhpmcounter29_c | csr_mhpmcounter30_c | csr_mhpmcounter31_c |
|
csr_mhpmcounter27_c | csr_mhpmcounter28_c | csr_mhpmcounter29_c | csr_mhpmcounter30_c | csr_mhpmcounter31_c |
|
csr_mhpmcounter3h_c | csr_mhpmcounter4h_c | csr_mhpmcounter5h_c | csr_mhpmcounter6h_c | csr_mhpmcounter7h_c | csr_mhpmcounter8h_c | -- counter HIGH
|
csr_mhpmcounter3h_c | csr_mhpmcounter4h_c | csr_mhpmcounter5h_c | csr_mhpmcounter6h_c | csr_mhpmcounter7h_c | csr_mhpmcounter8h_c | -- counter HIGH
|
csr_mhpmcounter9h_c | csr_mhpmcounter10h_c | csr_mhpmcounter11h_c | csr_mhpmcounter12h_c | csr_mhpmcounter13h_c | csr_mhpmcounter14h_c |
|
csr_mhpmcounter9h_c | csr_mhpmcounter10h_c | csr_mhpmcounter11h_c | csr_mhpmcounter12h_c | csr_mhpmcounter13h_c | csr_mhpmcounter14h_c |
|
csr_mhpmcounter15h_c | csr_mhpmcounter16h_c | csr_mhpmcounter17h_c | csr_mhpmcounter18h_c | csr_mhpmcounter19h_c | csr_mhpmcounter20h_c |
|
csr_mhpmcounter15h_c | csr_mhpmcounter16h_c | csr_mhpmcounter17h_c | csr_mhpmcounter18h_c | csr_mhpmcounter19h_c | csr_mhpmcounter20h_c |
|
csr_mhpmcounter21h_c | csr_mhpmcounter22h_c | csr_mhpmcounter23h_c | csr_mhpmcounter24h_c | csr_mhpmcounter25h_c | csr_mhpmcounter26h_c |
|
csr_mhpmcounter21h_c | csr_mhpmcounter22h_c | csr_mhpmcounter23h_c | csr_mhpmcounter24h_c | csr_mhpmcounter25h_c | csr_mhpmcounter26h_c |
|
csr_mhpmcounter27h_c | csr_mhpmcounter28h_c | csr_mhpmcounter29h_c | csr_mhpmcounter30h_c | csr_mhpmcounter31h_c |
|
csr_mhpmcounter27h_c | csr_mhpmcounter28h_c | csr_mhpmcounter29h_c | csr_mhpmcounter30h_c | csr_mhpmcounter31h_c |
|
csr_mhpmevent3_c | csr_mhpmevent4_c | csr_mhpmevent5_c | csr_mhpmevent6_c | csr_mhpmevent7_c | csr_mhpmevent8_c | -- event configuration
|
csr_mhpmevent3_c | csr_mhpmevent4_c | csr_mhpmevent5_c | csr_mhpmevent6_c | csr_mhpmevent7_c | csr_mhpmevent8_c | -- event configuration
|
csr_mhpmevent9_c | csr_mhpmevent10_c | csr_mhpmevent11_c | csr_mhpmevent12_c | csr_mhpmevent13_c | csr_mhpmevent14_c |
|
csr_mhpmevent9_c | csr_mhpmevent10_c | csr_mhpmevent11_c | csr_mhpmevent12_c | csr_mhpmevent13_c | csr_mhpmevent14_c |
|
csr_mhpmevent15_c | csr_mhpmevent16_c | csr_mhpmevent17_c | csr_mhpmevent18_c | csr_mhpmevent19_c | csr_mhpmevent20_c |
|
csr_mhpmevent15_c | csr_mhpmevent16_c | csr_mhpmevent17_c | csr_mhpmevent18_c | csr_mhpmevent19_c | csr_mhpmevent20_c |
|
csr_mhpmevent21_c | csr_mhpmevent22_c | csr_mhpmevent23_c | csr_mhpmevent24_c | csr_mhpmevent25_c | csr_mhpmevent26_c |
|
csr_mhpmevent21_c | csr_mhpmevent22_c | csr_mhpmevent23_c | csr_mhpmevent24_c | csr_mhpmevent25_c | csr_mhpmevent26_c |
|
csr_mhpmevent27_c | csr_mhpmevent28_c | csr_mhpmevent29_c | csr_mhpmevent30_c | csr_mhpmevent31_c =>
|
csr_mhpmevent27_c | csr_mhpmevent28_c | csr_mhpmevent29_c | csr_mhpmevent30_c | csr_mhpmevent31_c =>
|
csr_acc_valid <= csr.privilege_eff and bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zihpm); -- M-mode only
|
csr_acc_valid <= csr.privilege_eff and bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zihpm); -- M-mode only
|
|
|
-- -- user hardware performance monitors (HPM) --
|
-- -- user hardware performance monitors (HPM) --
|
-- when csr_hpmcounter3_c | csr_hpmcounter4_c | csr_hpmcounter5_c | csr_hpmcounter6_c | csr_hpmcounter7_c | csr_hpmcounter8_c | -- counter LOW
|
-- when csr_hpmcounter3_c | csr_hpmcounter4_c | csr_hpmcounter5_c | csr_hpmcounter6_c | csr_hpmcounter7_c | csr_hpmcounter8_c | -- counter LOW
|
-- csr_hpmcounter9_c | csr_hpmcounter10_c | csr_hpmcounter11_c | csr_hpmcounter12_c | csr_hpmcounter13_c | csr_hpmcounter14_c |
|
-- csr_hpmcounter9_c | csr_hpmcounter10_c | csr_hpmcounter11_c | csr_hpmcounter12_c | csr_hpmcounter13_c | csr_hpmcounter14_c |
|
-- csr_hpmcounter15_c | csr_hpmcounter16_c | csr_hpmcounter17_c | csr_hpmcounter18_c | csr_hpmcounter19_c | csr_hpmcounter20_c |
|
-- csr_hpmcounter15_c | csr_hpmcounter16_c | csr_hpmcounter17_c | csr_hpmcounter18_c | csr_hpmcounter19_c | csr_hpmcounter20_c |
|
-- csr_hpmcounter21_c | csr_hpmcounter22_c | csr_hpmcounter23_c | csr_hpmcounter24_c | csr_hpmcounter25_c | csr_hpmcounter26_c |
|
-- csr_hpmcounter21_c | csr_hpmcounter22_c | csr_hpmcounter23_c | csr_hpmcounter24_c | csr_hpmcounter25_c | csr_hpmcounter26_c |
|
-- csr_hpmcounter27_c | csr_hpmcounter28_c | csr_hpmcounter29_c | csr_hpmcounter30_c | csr_hpmcounter31_c |
|
-- csr_hpmcounter27_c | csr_hpmcounter28_c | csr_hpmcounter29_c | csr_hpmcounter30_c | csr_hpmcounter31_c |
|
-- csr_hpmcounter3h_c | csr_hpmcounter4h_c | csr_hpmcounter5h_c | csr_hpmcounter6h_c | csr_hpmcounter7h_c | csr_hpmcounter8h_c | -- counter HIGH
|
-- csr_hpmcounter3h_c | csr_hpmcounter4h_c | csr_hpmcounter5h_c | csr_hpmcounter6h_c | csr_hpmcounter7h_c | csr_hpmcounter8h_c | -- counter HIGH
|
-- csr_hpmcounter9h_c | csr_hpmcounter10h_c | csr_hpmcounter11h_c | csr_hpmcounter12h_c | csr_hpmcounter13h_c | csr_hpmcounter14h_c |
|
-- csr_hpmcounter9h_c | csr_hpmcounter10h_c | csr_hpmcounter11h_c | csr_hpmcounter12h_c | csr_hpmcounter13h_c | csr_hpmcounter14h_c |
|
-- csr_hpmcounter15h_c | csr_hpmcounter16h_c | csr_hpmcounter17h_c | csr_hpmcounter18h_c | csr_hpmcounter19h_c | csr_hpmcounter20h_c |
|
-- csr_hpmcounter15h_c | csr_hpmcounter16h_c | csr_hpmcounter17h_c | csr_hpmcounter18h_c | csr_hpmcounter19h_c | csr_hpmcounter20h_c |
|
-- csr_hpmcounter21h_c | csr_hpmcounter22h_c | csr_hpmcounter23h_c | csr_hpmcounter24h_c | csr_hpmcounter25h_c | csr_hpmcounter26h_c |
|
-- csr_hpmcounter21h_c | csr_hpmcounter22h_c | csr_hpmcounter23h_c | csr_hpmcounter24h_c | csr_hpmcounter25h_c | csr_hpmcounter26h_c |
|
-- csr_hpmcounter27h_c | csr_hpmcounter28h_c | csr_hpmcounter29h_c | csr_hpmcounter30h_c | csr_hpmcounter31h_c =>
|
-- csr_hpmcounter27h_c | csr_hpmcounter28h_c | csr_hpmcounter29h_c | csr_hpmcounter30h_c | csr_hpmcounter31h_c =>
|
-- csr_acc_valid <= '0'; -- >>> NOT IMPLEMENTED <<<
|
-- csr_acc_valid <= '0'; -- >>> NOT IMPLEMENTED <<<
|
|
|
-- user-level counters/timers (read-only) --
|
-- user-level counters/timers (read-only) --
|
when csr_cycle_c | csr_cycleh_c | csr_time_c | csr_timeh_c | csr_instret_c | csr_instreth_c =>
|
when csr_cycle_c | csr_cycleh_c | csr_time_c | csr_timeh_c | csr_instret_c | csr_instreth_c =>
|
case csr.addr(1 downto 0) is
|
case csr.addr(1 downto 0) is
|
when "00" => csr_acc_valid <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zicntr) and (not csr_wacc_v) and (csr.privilege_eff or csr.mcounteren_cy); -- cyle[h]: M-mode, U-mode if authorized, implemented at all, read-only
|
when "00" => csr_acc_valid <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zicntr) and (not csr_wacc_v) and (csr.privilege_eff or csr.mcounteren_cy); -- cyle[h]: M-mode, U-mode if authorized, implemented at all, read-only
|
when "01" => csr_acc_valid <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zicntr) and (not csr_wacc_v) and (csr.privilege_eff or csr.mcounteren_tm); -- time[h]: M-mode, U-mode if authorized, implemented at all, read-only
|
when "01" => csr_acc_valid <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zicntr) and (not csr_wacc_v) and (csr.privilege_eff or csr.mcounteren_tm); -- time[h]: M-mode, U-mode if authorized, implemented at all, read-only
|
when "10" => csr_acc_valid <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zicntr) and (not csr_wacc_v) and (csr.privilege_eff or csr.mcounteren_ir); -- instret[h]: M-mode, U-mode if authorized, implemented at all read-only
|
when "10" => csr_acc_valid <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zicntr) and (not csr_wacc_v) and (csr.privilege_eff or csr.mcounteren_ir); -- instret[h]: M-mode, U-mode if authorized, implemented at all read-only
|
when others => csr_acc_valid <= '0';
|
when others => csr_acc_valid <= '0';
|
end case;
|
end case;
|
|
|
-- debug mode CSRs --
|
-- debug mode CSRs --
|
when csr_dcsr_c | csr_dpc_c | csr_dscratch0_c =>
|
when csr_dcsr_c | csr_dpc_c | csr_dscratch0_c =>
|
csr_acc_valid <= debug_ctrl.running and bool_to_ulogic_f(CPU_EXTENSION_RISCV_DEBUG); -- access only in debug-mode
|
csr_acc_valid <= debug_ctrl.running and bool_to_ulogic_f(CPU_EXTENSION_RISCV_DEBUG); -- access only in debug-mode
|
|
|
-- trigger module CSRs --
|
-- trigger module CSRs --
|
when csr_tselect_c | csr_tdata1_c | csr_tdata2_c | csr_tdata3_c | csr_tinfo_c | csr_tcontrol_c | csr_mcontext_c | csr_scontext_c =>
|
when csr_tselect_c | csr_tdata1_c | csr_tdata2_c | csr_tdata3_c | csr_tinfo_c | csr_tcontrol_c | csr_mcontext_c | csr_scontext_c =>
|
-- access in debug-mode or M-mode (M-mode: writes to tdata* are ignored as DMODE is hardwired to 1)
|
-- access in debug-mode or M-mode (M-mode: writes to tdata* are ignored as DMODE is hardwired to 1)
|
csr_acc_valid <= (debug_ctrl.running or csr.privilege_eff) and bool_to_ulogic_f(CPU_EXTENSION_RISCV_DEBUG);
|
csr_acc_valid <= (debug_ctrl.running or csr.privilege_eff) and bool_to_ulogic_f(CPU_EXTENSION_RISCV_DEBUG);
|
|
|
-- undefined / not implemented --
|
-- undefined / not implemented --
|
when others =>
|
when others =>
|
csr_acc_valid <= '0'; -- invalid access
|
csr_acc_valid <= '0'; -- invalid access
|
end case;
|
end case;
|
end process csr_access_check;
|
end process csr_access_check;
|
|
|
|
|
-- Illegal Instruction Check --------------------------------------------------------------
|
-- Illegal Instruction Check --------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
illegal_instruction_check: process(execute_engine, decode_aux, csr, csr_acc_valid, debug_ctrl)
|
illegal_instruction_check: process(execute_engine, decode_aux, csr, csr_acc_valid, debug_ctrl)
|
variable opcode_v : std_ulogic_vector(6 downto 0);
|
|
begin
|
begin
|
-- defaults --
|
-- defaults --
|
illegal_instruction <= '0';
|
illegal_cmd <= '0';
|
illegal_register <= '0';
|
illegal_reg <= '0';
|
|
|
-- check opcode for rv32 --
|
-- check instruction word encoding and side effects --
|
if (execute_engine.i_reg(instr_opcode_lsb_c+1 downto instr_opcode_lsb_c) = "11") then
|
case execute_engine.i_reg(instr_opcode_msb_c downto instr_opcode_lsb_c) is
|
illegal_opcode_lsbs <= '0';
|
|
else
|
|
illegal_opcode_lsbs <= '1';
|
|
end if;
|
|
|
|
-- check for illegal compressed instruction --
|
when opcode_lui_c | opcode_auipc_c | opcode_jal_c => -- LUI, UIPC, JAL (only check actual OPCODE)
|
if (CPU_EXTENSION_RISCV_C = true) then
|
-- ------------------------------------------------------------
|
illegal_compressed <= execute_engine.is_ici;
|
illegal_cmd <= '0';
|
else
|
illegal_reg <= execute_engine.i_reg(instr_rd_msb_c); -- illegal 'E' register?
|
illegal_compressed <= '0';
|
|
end if;
|
|
|
|
-- check instructions --
|
when opcode_jalr_c => -- check JALR.funct3
|
opcode_v := execute_engine.i_reg(instr_opcode_msb_c downto instr_opcode_lsb_c+2) & "11"; -- save some bits here, LSBs are always 11 for rv32
|
-- ------------------------------------------------------------
|
case opcode_v is
|
case execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) is
|
|
when "000" => illegal_cmd <= '0';
|
|
when others => illegal_cmd <= '1';
|
|
end case;
|
|
illegal_reg <= execute_engine.i_reg(instr_rs1_msb_c) or execute_engine.i_reg(instr_rd_msb_c); -- illegal 'E' register?
|
|
|
when opcode_lui_c | opcode_auipc_c | opcode_jal_c => -- check sufficient LUI, UIPC, JAL (only check actual OPCODE)
|
when opcode_branch_c => -- check BRANCH.funct3
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
illegal_instruction <= '0';
|
case execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) is
|
-- illegal E-CPU register? --
|
when funct3_beq_c | funct3_bne_c | funct3_blt_c | funct3_bge_c | funct3_bltu_c | funct3_bgeu_c => illegal_cmd <= '0';
|
illegal_register <= execute_engine.i_reg(instr_rd_msb_c);
|
when others => illegal_cmd <= '1';
|
|
end case;
|
|
illegal_reg <= execute_engine.i_reg(instr_rs2_msb_c) or execute_engine.i_reg(instr_rs1_msb_c); -- illegal 'E' register?
|
|
|
|
when opcode_load_c => -- check LOAD.funct3
|
|
-- ------------------------------------------------------------
|
|
case execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) is
|
|
when funct3_lb_c | funct3_lh_c | funct3_lw_c | funct3_lbu_c | funct3_lhu_c => illegal_cmd <= '0';
|
|
when others => illegal_cmd <= '1';
|
|
end case;
|
|
illegal_reg <= execute_engine.i_reg(instr_rs1_msb_c) or execute_engine.i_reg(instr_rd_msb_c); -- illegal 'E' register?
|
|
|
|
when opcode_store_c => -- check STORE.funct3
|
|
-- ------------------------------------------------------------
|
|
case execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) is
|
|
when funct3_sb_c | funct3_sh_c | funct3_sw_c => illegal_cmd <= '0';
|
|
when others => illegal_cmd <= '1';
|
|
end case;
|
|
illegal_reg <= execute_engine.i_reg(instr_rs2_msb_c) or execute_engine.i_reg(instr_rs1_msb_c); -- illegal 'E' register?
|
|
|
when opcode_alu_c => -- check ALU.funct3 & ALU.funct7
|
when opcode_alu_c => -- check ALU.funct3 & ALU.funct7
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
if (((execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_subadd_c) or (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_sr_c)) and
|
if ((((execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_subadd_c) or (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_sr_c)) and
|
(execute_engine.i_reg(instr_funct7_msb_c-2 downto instr_funct7_lsb_c) = "00000") and (execute_engine.i_reg(instr_funct7_msb_c) = '0')) or
|
(execute_engine.i_reg(instr_funct7_msb_c-2 downto instr_funct7_lsb_c) = "00000") and (execute_engine.i_reg(instr_funct7_msb_c) = '0')) or
|
(((execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_sll_c) or
|
(((execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_sll_c) or
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_slt_c) or
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_slt_c) or
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_sltu_c) or
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_sltu_c) or
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_xor_c) or
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_xor_c) or
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_or_c) or
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_or_c) or
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_and_c)) and
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_and_c)) and
|
(execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0000000")) then -- valid base ALUI instruction?
|
(execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0000000"))) or -- valid base ALU instruction?
|
illegal_instruction <= '0';
|
(((CPU_EXTENSION_RISCV_M = true) or (CPU_EXTENSION_RISCV_Zmmul = true)) and (decode_aux.is_m_mul = '1')) or -- valid MUL instruction?
|
elsif ((CPU_EXTENSION_RISCV_M = true) or (CPU_EXTENSION_RISCV_Zmmul = false)) and (decode_aux.is_m_mul = '1') then -- valid MUL instruction?
|
((CPU_EXTENSION_RISCV_M = true) and (decode_aux.is_m_div = '1')) or -- valid DIV instruction?
|
illegal_instruction <= '0';
|
((CPU_EXTENSION_RISCV_B = true) and (decode_aux.is_b_reg = '1')) then -- valid BITMANIP register instruction?
|
elsif (CPU_EXTENSION_RISCV_M = true) and (decode_aux.is_m_div = '1') then -- valid DIV instruction?
|
illegal_cmd <= '0';
|
illegal_instruction <= '0';
|
|
elsif (CPU_EXTENSION_RISCV_B = true) and (decode_aux.is_b_reg = '1') then -- valid BITMANIP instruction?
|
|
illegal_instruction <= '0';
|
|
else
|
else
|
illegal_instruction <= '1';
|
illegal_cmd <= '1';
|
end if;
|
end if;
|
-- illegal E-CPU register? --
|
illegal_reg <= execute_engine.i_reg(instr_rd_msb_c) or execute_engine.i_reg(instr_rs1_msb_c) or execute_engine.i_reg(instr_rs2_msb_c); -- illegal 'E' register?
|
illegal_register <= execute_engine.i_reg(instr_rd_msb_c) or execute_engine.i_reg(instr_rs1_msb_c) or execute_engine.i_reg(instr_rs2_msb_c);
|
|
|
|
when opcode_alui_c => -- check ALUI.funct7
|
when opcode_alui_c => -- check ALU.funct3 & ALU.funct7
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
if (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_subadd_c) or
|
if ((execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_subadd_c) or
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_slt_c) or
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_slt_c) or
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_sltu_c) or
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_sltu_c) or
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_xor_c) or
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_xor_c) or
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_or_c) or
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_or_c) or
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_and_c) or
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_and_c) or
|
((execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_sll_c) and -- shift logical left
|
((execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_sll_c) and
|
(execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0000000")) or
|
(execute_engine.i_reg(instr_funct7_msb_c downto instr_funct7_lsb_c) = "0000000")) or
|
((execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_sr_c) and -- shift right
|
((execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_sr_c) and
|
((execute_engine.i_reg(instr_funct7_msb_c-2 downto instr_funct7_lsb_c) = "00000") and (execute_engine.i_reg(instr_funct7_msb_c) = '0'))) then -- valid base ALUI instruction?
|
((execute_engine.i_reg(instr_funct7_msb_c-2 downto instr_funct7_lsb_c) = "00000") and (execute_engine.i_reg(instr_funct7_msb_c) = '0')))) or -- valid base ALUI instruction?
|
illegal_instruction <= '0';
|
((CPU_EXTENSION_RISCV_B = true) and (decode_aux.is_b_imm = '1')) then -- valid BITMANIP immediate instruction?
|
elsif (CPU_EXTENSION_RISCV_B = true) and (decode_aux.is_b_imm = '1') then -- valid BITMANIP immediate instruction?
|
illegal_cmd <= '0';
|
illegal_instruction <= '0';
|
|
else
|
else
|
illegal_instruction <= '1';
|
illegal_cmd <= '1';
|
end if;
|
end if;
|
-- illegal E-CPU register? --
|
illegal_reg <= execute_engine.i_reg(instr_rs1_msb_c) or execute_engine.i_reg(instr_rd_msb_c); -- illegal 'E' register?
|
illegal_register <= execute_engine.i_reg(instr_rs1_msb_c) or execute_engine.i_reg(instr_rd_msb_c);
|
|
|
|
when opcode_load_c => -- check LOAD.funct3
|
when opcode_fence_c => -- check FENCE.funct3, ignore all remaining bit-fields
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
if (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_lb_c) or
|
case execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) is
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_lh_c) or
|
when funct3_fence_c => illegal_cmd <= '0'; -- FENCE
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_lw_c) or
|
when funct3_fencei_c => illegal_cmd <= not bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zifencei); -- FENCE.I
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_lbu_c) or
|
when others => illegal_cmd <= '1';
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_lhu_c) then
|
end case;
|
illegal_instruction <= '0';
|
|
else
|
|
illegal_instruction <= '1';
|
|
end if;
|
|
-- illegal E-CPU register? --
|
|
illegal_register <= execute_engine.i_reg(instr_rs1_msb_c) or execute_engine.i_reg(instr_rd_msb_c);
|
|
|
|
when opcode_store_c => -- check STORE.funct3
|
|
-- ------------------------------------------------------------
|
|
if (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_sb_c) or
|
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_sh_c) or
|
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_sw_c) then
|
|
illegal_instruction <= '0';
|
|
else
|
|
illegal_instruction <= '1';
|
|
end if;
|
|
-- illegal E-CPU register? --
|
|
illegal_register <= execute_engine.i_reg(instr_rs2_msb_c) or execute_engine.i_reg(instr_rs1_msb_c);
|
|
|
|
when opcode_atomic_c => -- atomic instructions
|
|
-- ------------------------------------------------------------
|
|
if (CPU_EXTENSION_RISCV_A = true) then
|
|
if (execute_engine.i_reg(instr_funct5_msb_c downto instr_funct5_lsb_c) = "00010") then -- LR
|
|
illegal_instruction <= '0';
|
|
-- illegal E-CPU register? --
|
|
illegal_register <= execute_engine.i_reg(instr_rs1_msb_c) or execute_engine.i_reg(instr_rd_msb_c);
|
|
elsif (execute_engine.i_reg(instr_funct5_msb_c downto instr_funct5_lsb_c) = "00011") then -- SC
|
|
illegal_instruction <= '0';
|
|
-- illegal E-CPU register? --
|
|
illegal_register <= execute_engine.i_reg(instr_rs1_msb_c) or execute_engine.i_reg(instr_rs2_msb_c) or execute_engine.i_reg(instr_rd_msb_c);
|
|
else
|
|
illegal_instruction <= '1';
|
|
end if;
|
|
else
|
|
illegal_instruction <= '1';
|
|
end if;
|
|
|
|
when opcode_branch_c => -- check BRANCH.funct3
|
when opcode_atomic_c => -- check AMO.funct3 and AMO.funct5
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
if (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_beq_c) or
|
if (CPU_EXTENSION_RISCV_A = true) and (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "010") and
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_bne_c) or
|
(execute_engine.i_reg(instr_funct5_msb_c downto instr_funct5_lsb_c+1) = "0001") then -- LR/SC
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_blt_c) or
|
illegal_cmd <= '0';
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_bge_c) or
|
else
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_bltu_c) or
|
illegal_cmd <= '1';
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_bgeu_c) then
|
end if;
|
illegal_instruction <= '0';
|
illegal_reg <= execute_engine.i_reg(instr_rs1_msb_c) or execute_engine.i_reg(instr_rs2_msb_c) or execute_engine.i_reg(instr_rd_msb_c); -- illegal 'E' register?
|
|
|
|
when opcode_system_c => -- check system instructions
|
|
-- ------------------------------------------------------------
|
|
if (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_env_c) then -- system environment
|
|
if (decode_aux.rs1_zero = '1') and (decode_aux.rd_zero = '1') then
|
|
case execute_engine.i_reg(instr_funct12_msb_c downto instr_funct12_lsb_c) is
|
|
when funct12_ecall_c | funct12_ebreak_c => illegal_cmd <= '0'; -- ECALL, EBREAK
|
|
when funct12_mret_c => illegal_cmd <= not csr.privilege; -- MRET (only allowed in ACTUAL M-mode)
|
|
when funct12_wfi_c => illegal_cmd <= (not csr.privilege) and csr.mstatus_tw; -- WFI (only allowed in ACTUAL M-mode or if mstatus.TW = 0)
|
|
when funct12_dret_c => illegal_cmd <= not debug_ctrl.running; -- DRET (only allowed in D-mode)
|
|
when others => illegal_cmd <= '1';
|
|
end case;
|
else
|
else
|
illegal_instruction <= '1';
|
illegal_cmd <= '1';
|
end if;
|
end if;
|
-- illegal E-CPU register? --
|
else -- CSR access
|
illegal_register <= execute_engine.i_reg(instr_rs2_msb_c) or execute_engine.i_reg(instr_rs1_msb_c);
|
if (csr_acc_valid = '0') then -- invalid CSR access?
|
|
illegal_cmd <= '1';
|
when opcode_jalr_c => -- check JALR.funct3
|
|
-- ------------------------------------------------------------
|
|
if (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "000") then
|
|
illegal_instruction <= '0';
|
|
else
|
|
illegal_instruction <= '1';
|
|
end if;
|
end if;
|
-- illegal E-CPU register? --
|
|
illegal_register <= execute_engine.i_reg(instr_rs1_msb_c) or execute_engine.i_reg(instr_rd_msb_c);
|
|
|
|
when opcode_fence_c => -- check FENCE.funct3
|
|
-- ------------------------------------------------------------
|
|
if ((execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_fencei_c) and (CPU_EXTENSION_RISCV_Zifencei = true)) or -- FENCE.I
|
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_fence_c) then -- FENCE
|
|
illegal_instruction <= '0';
|
|
else
|
|
illegal_instruction <= '1';
|
|
end if;
|
end if;
|
-- NOTE: ignore all remaining bit fields here
|
|
|
|
when opcode_syscsr_c => -- check system instructions
|
|
-- ------------------------------------------------------------
|
|
-- CSR access --
|
|
if ((execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_csrrw_c) or
|
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_csrrs_c) or
|
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_csrrc_c) or
|
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_csrrwi_c) or
|
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_csrrsi_c) or
|
|
(execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = funct3_csrrci_c)) and
|
|
(csr_acc_valid = '1') then -- valid CSR access?
|
|
illegal_instruction <= '0';
|
|
-- illegal E-CPU register? --
|
-- illegal E-CPU register? --
|
if (execute_engine.i_reg(instr_funct3_msb_c) = '0') then -- reg-reg CSR
|
if (execute_engine.i_reg(instr_funct3_msb_c) = '0') then -- reg-reg CSR (or ENV where rd=rs1=zero)
|
illegal_register <= execute_engine.i_reg(instr_rs1_msb_c) or execute_engine.i_reg(instr_rd_msb_c);
|
illegal_reg <= execute_engine.i_reg(instr_rd_msb_c) or execute_engine.i_reg(instr_rs1_msb_c);
|
else -- reg-imm CSR
|
else -- reg-imm CSR
|
illegal_register <= execute_engine.i_reg(instr_rd_msb_c);
|
illegal_reg <= execute_engine.i_reg(instr_rd_msb_c);
|
end if;
|
|
-- system: ecall, ebreak, mret, wfi, dret --
|
|
-- > WFI is always allowed to execute in M-mode; in U-mode it is allowed to execute if mstatus.TW = 0
|
|
elsif (execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) = "000") and
|
|
(decode_aux.rs1_zero = '1') and (decode_aux.rd_zero = '1') and
|
|
((execute_engine.i_reg(instr_funct12_msb_c downto instr_funct12_lsb_c) = funct12_ecall_c) or -- ECALL
|
|
(execute_engine.i_reg(instr_funct12_msb_c downto instr_funct12_lsb_c) = funct12_ebreak_c) or -- EBREAK
|
|
((execute_engine.i_reg(instr_funct12_msb_c downto instr_funct12_lsb_c) = funct12_mret_c) and (csr.privilege = priv_mode_m_c)) or -- MRET (only allowed in ACTUAL M-mode)
|
|
((execute_engine.i_reg(instr_funct12_msb_c downto instr_funct12_lsb_c) = funct12_dret_c) and (CPU_EXTENSION_RISCV_DEBUG = true) and (debug_ctrl.running = '1')) or -- DRET (only allowed in D-mode)
|
|
((execute_engine.i_reg(instr_funct12_msb_c downto instr_funct12_lsb_c) = funct12_wfi_c) and ((csr.privilege = priv_mode_m_c) or (csr.mstatus_tw = '0')))) then -- WFI
|
|
illegal_instruction <= '0';
|
|
else
|
|
illegal_instruction <= '1';
|
|
end if;
|
end if;
|
|
|
when opcode_fop_c => -- floating point operations - single/dual operands
|
when opcode_fop_c => -- floating point operations - single/dual operands
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
if (CPU_EXTENSION_RISCV_Zfinx = true) and -- F extension implemented
|
if (CPU_EXTENSION_RISCV_Zfinx = true) and -- F extension implemented
|
(execute_engine.i_reg(instr_funct7_lsb_c+1 downto instr_funct7_lsb_c) = float_single_c) and -- single-precision operations only
|
(execute_engine.i_reg(instr_funct7_lsb_c+1 downto instr_funct7_lsb_c) = float_single_c) and -- single-precision operations only
|
(decode_aux.is_f_op = '1') then -- is correct/supported floating-point instruction
|
(decode_aux.is_f_op = '1') then -- is correct/supported floating-point instruction
|
illegal_instruction <= '0';
|
illegal_cmd <= '0';
|
else
|
else
|
illegal_instruction <= '1';
|
illegal_cmd <= '1';
|
end if;
|
end if;
|
-- illegal E-CPU register? --
|
illegal_reg <= execute_engine.i_reg(instr_rs2_msb_c) or execute_engine.i_reg(instr_rs1_msb_c) or execute_engine.i_reg(instr_rd_msb_c); -- illegal 'E' register?
|
-- FIXME: rs2 is not checked!
|
|
illegal_register <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zfinx) and (execute_engine.i_reg(instr_rs1_msb_c) or execute_engine.i_reg(instr_rd_msb_c));
|
|
|
|
when opcode_cust0_c => -- CFU: custom instructions
|
when opcode_cust0_c => -- CFU: custom instructions
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
if (CPU_EXTENSION_RISCV_Zxcfu = true) then -- CFU extension implemented
|
illegal_cmd <= not bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zxcfu); -- CFU extension not implemented
|
illegal_instruction <= '0';
|
illegal_reg <= execute_engine.i_reg(instr_rs2_msb_c) or execute_engine.i_reg(instr_rs1_msb_c) or execute_engine.i_reg(instr_rd_msb_c); -- illegal 'E' register?
|
else
|
|
illegal_instruction <= '1';
|
|
end if;
|
|
-- illegal E-CPU register? --
|
|
illegal_register <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zxcfu) and (execute_engine.i_reg(instr_rs2_msb_c) or execute_engine.i_reg(instr_rs1_msb_c) or execute_engine.i_reg(instr_rd_msb_c));
|
|
|
|
when others => -- undefined instruction -> illegal!
|
when others => -- illegal opcode
|
-- ------------------------------------------------------------
|
-- ------------------------------------------------------------
|
illegal_instruction <= '1';
|
illegal_cmd <= '1';
|
|
|
end case;
|
end case;
|
end process illegal_instruction_check;
|
end process illegal_instruction_check;
|
|
|
|
|
-- Illegal Operation Check ----------------------------------------------------------------
|
-- Illegal Operation Check ----------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- check in EXECUTE state: any illegal condition? --
|
-- check in EXECUTE state: any illegal condition? --
|
trap_ctrl.instr_il <= (illegal_opcode_lsbs or -- illegal opcode LSB bits - not rv32
|
trap_ctrl.instr_il <= (illegal_cmd or -- illegal instruction
|
illegal_instruction or -- illegal instruction
|
(bool_to_ulogic_f(CPU_EXTENSION_RISCV_E) and illegal_reg) or -- illegal register access in E extension
|
(bool_to_ulogic_f(CPU_EXTENSION_RISCV_E) and illegal_register) or -- illegal register access in E extension
|
(bool_to_ulogic_f(CPU_EXTENSION_RISCV_C) and execute_engine.is_ici)) -- illegal compressed instruction
|
illegal_compressed) -- illegal compressed instruction
|
when (execute_engine.state = EXECUTE) else '0'; -- evaluate in EXECUTE stage only
|
when (execute_engine.state = EXECUTE) else '0';
|
|
|
|
|
|
-- ****************************************************************************************************************************
|
-- ****************************************************************************************************************************
|
-- Exception and Interrupt (= Traps) Control
|
-- Exception and Interrupt (= Traps) Control
|
-- ****************************************************************************************************************************
|
-- ****************************************************************************************************************************
|
|
|
-- Trap Controller ------------------------------------------------------------------------
|
-- Trap Controller ------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
trap_controller: process(rstn_i, clk_i)
|
trap_controller: process(rstn_i, clk_i)
|
variable mode_m_v, mode_u_v : std_ulogic;
|
|
begin
|
begin
|
if (rstn_i = '0') then
|
if (rstn_i = '0') then
|
trap_ctrl.exc_buf <= (others => '0');
|
trap_ctrl.exc_buf <= (others => '0');
|
trap_ctrl.irq_buf <= (others => '0');
|
trap_ctrl.irq_buf <= (others => '0');
|
trap_ctrl.env_start <= '0';
|
trap_ctrl.env_start <= '0';
|
trap_ctrl.cause <= (others => '0');
|
trap_ctrl.cause <= (others => '0');
|
elsif rising_edge(clk_i) then
|
elsif rising_edge(clk_i) then
|
if (CPU_EXTENSION_RISCV_Zicsr = true) then
|
if (CPU_EXTENSION_RISCV_Zicsr = true) then
|
-- > clear all queued exception triggers when starting the trap handling environment (trap_ctrl.env_start = 1)
|
-- > clear all queued exception triggers when starting the trap handling environment (trap_ctrl.env_start = 1)
|
|
|
-- exception queue: misaligned load/store/instruction address --
|
-- exception queue: misaligned load/store/instruction address --
|
trap_ctrl.exc_buf(exc_lalign_c) <= (trap_ctrl.exc_buf(exc_lalign_c) or ma_load_i) and (not trap_ctrl.env_start);
|
trap_ctrl.exc_buf(exc_lalign_c) <= (trap_ctrl.exc_buf(exc_lalign_c) or ma_load_i) and (not trap_ctrl.env_start);
|
trap_ctrl.exc_buf(exc_salign_c) <= (trap_ctrl.exc_buf(exc_salign_c) or ma_store_i) and (not trap_ctrl.env_start);
|
trap_ctrl.exc_buf(exc_salign_c) <= (trap_ctrl.exc_buf(exc_salign_c) or ma_store_i) and (not trap_ctrl.env_start);
|
trap_ctrl.exc_buf(exc_ialign_c) <= (trap_ctrl.exc_buf(exc_ialign_c) or trap_ctrl.instr_ma) and (not trap_ctrl.env_start);
|
trap_ctrl.exc_buf(exc_ialign_c) <= (trap_ctrl.exc_buf(exc_ialign_c) or trap_ctrl.instr_ma) and (not trap_ctrl.env_start);
|
|
|
-- exception queue: load/store/instruction bus access error --
|
-- exception queue: load/store/instruction bus access error --
|
trap_ctrl.exc_buf(exc_laccess_c) <= (trap_ctrl.exc_buf(exc_laccess_c) or be_load_i) and (not trap_ctrl.env_start);
|
trap_ctrl.exc_buf(exc_laccess_c) <= (trap_ctrl.exc_buf(exc_laccess_c) or be_load_i) and (not trap_ctrl.env_start);
|
trap_ctrl.exc_buf(exc_saccess_c) <= (trap_ctrl.exc_buf(exc_saccess_c) or be_store_i) and (not trap_ctrl.env_start);
|
trap_ctrl.exc_buf(exc_saccess_c) <= (trap_ctrl.exc_buf(exc_saccess_c) or be_store_i) and (not trap_ctrl.env_start);
|
trap_ctrl.exc_buf(exc_iaccess_c) <= (trap_ctrl.exc_buf(exc_iaccess_c) or trap_ctrl.instr_be) and (not trap_ctrl.env_start);
|
trap_ctrl.exc_buf(exc_iaccess_c) <= (trap_ctrl.exc_buf(exc_iaccess_c) or trap_ctrl.instr_be) and (not trap_ctrl.env_start);
|
|
|
-- exception queue: illegal instruction / environment calls --
|
-- exception queue: illegal instruction / environment calls --
|
trap_ctrl.exc_buf(exc_m_envcall_c) <= (trap_ctrl.exc_buf(exc_m_envcall_c) or (trap_ctrl.env_call and ( csr.privilege))) and (not trap_ctrl.env_start);
|
trap_ctrl.exc_buf(exc_m_envcall_c) <= (trap_ctrl.exc_buf(exc_m_envcall_c) or (trap_ctrl.env_call and ( csr.privilege))) and (not trap_ctrl.env_start);
|
trap_ctrl.exc_buf(exc_u_envcall_c) <= (trap_ctrl.exc_buf(exc_u_envcall_c) or (trap_ctrl.env_call and (not csr.privilege))) and (not trap_ctrl.env_start);
|
trap_ctrl.exc_buf(exc_u_envcall_c) <= (trap_ctrl.exc_buf(exc_u_envcall_c) or (trap_ctrl.env_call and (not csr.privilege))) and (not trap_ctrl.env_start);
|
trap_ctrl.exc_buf(exc_iillegal_c) <= (trap_ctrl.exc_buf(exc_iillegal_c) or trap_ctrl.instr_il) and (not trap_ctrl.env_start);
|
trap_ctrl.exc_buf(exc_iillegal_c) <= (trap_ctrl.exc_buf(exc_iillegal_c) or trap_ctrl.instr_il) and (not trap_ctrl.env_start);
|
|
|
-- exception queue: break point --
|
-- exception queue: break point --
|
if (CPU_EXTENSION_RISCV_DEBUG = true) then
|
if (CPU_EXTENSION_RISCV_DEBUG = true) then
|
trap_ctrl.exc_buf(exc_break_c) <= (not trap_ctrl.env_start) and (trap_ctrl.exc_buf(exc_break_c) or
|
trap_ctrl.exc_buf(exc_break_c) <= (not trap_ctrl.env_start) and (trap_ctrl.exc_buf(exc_break_c) or
|
(trap_ctrl.break_point and ( csr.privilege) and (not csr.dcsr_ebreakm) and (not debug_ctrl.running)) or -- break to machine-trap-handler when in machine mode on "ebreak"
|
(trap_ctrl.break_point and ( csr.privilege) and (not csr.dcsr_ebreakm) and (not debug_ctrl.running)) or -- break to machine-trap-handler when in machine mode on "ebreak"
|
(trap_ctrl.break_point and (not csr.privilege) and (not csr.dcsr_ebreaku) and (not debug_ctrl.running))); -- break to machine-trap-handler when in user mode on "ebreak"
|
(trap_ctrl.break_point and (not csr.privilege) and (not csr.dcsr_ebreaku) and (not debug_ctrl.running))); -- break to machine-trap-handler when in user mode on "ebreak"
|
else
|
else
|
trap_ctrl.exc_buf(exc_break_c) <= (trap_ctrl.exc_buf(exc_break_c) or trap_ctrl.break_point) and (not trap_ctrl.env_start);
|
trap_ctrl.exc_buf(exc_break_c) <= (trap_ctrl.exc_buf(exc_break_c) or trap_ctrl.break_point) and (not trap_ctrl.env_start);
|
end if;
|
end if;
|
|
|
-- exception queue / interrupt buffer: enter debug mode --
|
-- exception queue / interrupt buffer: enter debug mode --
|
if (CPU_EXTENSION_RISCV_DEBUG = true) then
|
if (CPU_EXTENSION_RISCV_DEBUG = true) then
|
trap_ctrl.exc_buf(exc_db_break_c) <= (trap_ctrl.exc_buf(exc_db_break_c) or debug_ctrl.trig_break) and (not trap_ctrl.env_start);
|
trap_ctrl.exc_buf(exc_db_break_c) <= (trap_ctrl.exc_buf(exc_db_break_c) or debug_ctrl.trig_break) and (not trap_ctrl.env_start);
|
trap_ctrl.exc_buf(exc_db_hw_c) <= (trap_ctrl.exc_buf(exc_db_hw_c) or debug_ctrl.trig_hw) and (not trap_ctrl.env_start);
|
trap_ctrl.exc_buf(exc_db_hw_c) <= (trap_ctrl.exc_buf(exc_db_hw_c) or debug_ctrl.trig_hw) and (not trap_ctrl.env_start);
|
trap_ctrl.irq_buf(irq_db_halt_c) <= debug_ctrl.trig_halt;
|
trap_ctrl.irq_buf(irq_db_halt_c) <= debug_ctrl.trig_halt;
|
trap_ctrl.irq_buf(irq_db_step_c) <= debug_ctrl.trig_step;
|
trap_ctrl.irq_buf(irq_db_step_c) <= debug_ctrl.trig_step;
|
end if;
|
end if;
|
|
|
-- interrupt buffer: machine software/external/timer interrupt --
|
-- interrupt buffer: machine software/external/timer interrupt --
|
trap_ctrl.irq_buf(irq_msw_irq_c) <= csr.mie_msie and msw_irq_i;
|
trap_ctrl.irq_buf(irq_msw_irq_c) <= csr.mie_msie and msw_irq_i;
|
trap_ctrl.irq_buf(irq_mext_irq_c) <= csr.mie_meie and mext_irq_i;
|
trap_ctrl.irq_buf(irq_mext_irq_c) <= csr.mie_meie and mext_irq_i;
|
trap_ctrl.irq_buf(irq_mtime_irq_c) <= csr.mie_mtie and mtime_irq_i;
|
trap_ctrl.irq_buf(irq_mtime_irq_c) <= csr.mie_mtie and mtime_irq_i;
|
|
|
-- interrupt *queue*: NEORV32-specific fast interrupts (FIRQ) - require manual ACK/clear --
|
-- interrupt *queue*: NEORV32-specific fast interrupts (FIRQ) - require manual ACK/clear --
|
trap_ctrl.irq_buf(irq_firq_15_c downto irq_firq_0_c) <= (trap_ctrl.irq_buf(irq_firq_15_c downto irq_firq_0_c) or (csr.mie_firqe and firq_i)) and csr.mip_firq_nclr;
|
trap_ctrl.irq_buf(irq_firq_15_c downto irq_firq_0_c) <= (trap_ctrl.irq_buf(irq_firq_15_c downto irq_firq_0_c) or (csr.mie_firqe and firq_i)) and csr.mip_firq_nclr;
|
|
|
-- trap environment control --
|
-- trap environment control --
|
if (trap_ctrl.env_start = '0') then -- no started trap handler
|
if (trap_ctrl.env_start = '0') then -- no started trap handler
|
if (trap_ctrl.exc_fire = '1') or ((trap_ctrl.irq_fire = '1') and -- exception triggered!
|
if (trap_ctrl.exc_fire = '1') or ((trap_ctrl.irq_fire = '1') and -- exception triggered!
|
((execute_engine.state = EXECUTE) or (execute_engine.state = TRAP_ENTER))) then -- fire IRQs in EXECUTE or TRAP state only to continue execution even on permanent IRQ
|
((execute_engine.state = EXECUTE) or (execute_engine.state = TRAP_ENTER))) then -- fire IRQs in EXECUTE or TRAP state only to continue execution even on permanent IRQ
|
trap_ctrl.cause <= trap_ctrl.cause_nxt; -- capture trap ID for mcause csr
|
trap_ctrl.cause <= trap_ctrl.cause_nxt; -- capture trap ID for mcause csr
|
trap_ctrl.env_start <= '1'; -- now execute engine can start trap handler
|
trap_ctrl.env_start <= '1'; -- now execute engine can start trap handler
|
end if;
|
end if;
|
elsif (trap_ctrl.env_start_ack = '1') then -- start of trap handler acknowledged by execute engine
|
elsif (trap_ctrl.env_start_ack = '1') then -- start of trap handler acknowledged by execute engine
|
trap_ctrl.env_start <= '0';
|
trap_ctrl.env_start <= '0';
|
end if;
|
end if;
|
end if;
|
end if;
|
end if;
|
end if;
|
end process trap_controller;
|
end process trap_controller;
|
|
|
-- any exception/interrupt? --
|
-- any exception/interrupt? --
|
trap_ctrl.exc_fire <= or_reduce_f(trap_ctrl.exc_buf); -- sync. exceptions CANNOT be masked
|
trap_ctrl.exc_fire <= '1' when (or_reduce_f(trap_ctrl.exc_buf) = '1') else '0'; -- sync. exceptions CANNOT be masked
|
trap_ctrl.irq_fire <= (or_reduce_f(trap_ctrl.irq_buf) and csr.mstatus_mie and trap_ctrl.db_irq_en) or trap_ctrl.db_irq_fire; -- interrupts CAN be masked (but not the DEBUG halt IRQ)
|
trap_ctrl.irq_fire <= '1' when ((or_reduce_f(trap_ctrl.irq_buf) = '1') and (csr.mstatus_mie = '1') and (trap_ctrl.db_irq_en = '1')) or -- interrupts CAN be masked
|
|
(trap_ctrl.db_irq_fire = '1') else '0'; -- but not the DEBUG halt IRQ
|
|
|
-- debug mode (entry) interrupts --
|
-- debug mode (entry) interrupts --
|
trap_ctrl.db_irq_en <= '0' when (CPU_EXTENSION_RISCV_DEBUG = true) and ((debug_ctrl.running = '1') or (csr.dcsr_step = '1')) else '1'; -- no interrupts when IN debug mode or IN single-step mode
|
trap_ctrl.db_irq_en <= '0' when (CPU_EXTENSION_RISCV_DEBUG = true) and ((debug_ctrl.running = '1') or (csr.dcsr_step = '1')) else '1'; -- no interrupts when IN debug mode or IN single-step mode
|
trap_ctrl.db_irq_fire <= (trap_ctrl.irq_buf(irq_db_step_c) or trap_ctrl.irq_buf(irq_db_halt_c)) when (CPU_EXTENSION_RISCV_DEBUG = true) else '0'; -- "NMI" for debug mode entry
|
trap_ctrl.db_irq_fire <= (trap_ctrl.irq_buf(irq_db_step_c) or trap_ctrl.irq_buf(irq_db_halt_c)) when (CPU_EXTENSION_RISCV_DEBUG = true) else '0'; -- "NMI" for debug mode entry
|
|
|
|
|
-- Trap Priority Encoder ------------------------------------------------------------------
|
-- Trap Priority Encoder ------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
trap_priority: process(trap_ctrl)
|
trap_priority: process(trap_ctrl)
|
begin
|
begin
|
-- ----------------------------------------------------------------------------------------
|
-- ----------------------------------------------------------------------------------------
|
-- the following traps are caused by *synchronous* exceptions; we do not need a
|
-- the following traps are caused by *synchronous* exceptions; we do not need a
|
-- specific acknowledge mask since only _one_ exception (the one with highest priority)
|
-- specific acknowledge mask since only _one_ exception (the one with highest priority)
|
-- is allowed to kick in at once
|
-- is allowed to kick in at once
|
-- ----------------------------------------------------------------------------------------
|
-- ----------------------------------------------------------------------------------------
|
|
|
-- exception: 0.0 instruction address misaligned --
|
-- exception: 0.0 instruction address misaligned --
|
if (trap_ctrl.exc_buf(exc_ialign_c) = '1') then
|
if (trap_ctrl.exc_buf(exc_ialign_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_ima_c;
|
trap_ctrl.cause_nxt <= trap_ima_c;
|
|
|
-- exception: 0.1 instruction access fault --
|
-- exception: 0.1 instruction access fault --
|
elsif (trap_ctrl.exc_buf(exc_iaccess_c) = '1') then
|
elsif (trap_ctrl.exc_buf(exc_iaccess_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_iba_c;
|
trap_ctrl.cause_nxt <= trap_iba_c;
|
|
|
-- exception: 0.2 illegal instruction --
|
-- exception: 0.2 illegal instruction --
|
elsif (trap_ctrl.exc_buf(exc_iillegal_c) = '1') then
|
elsif (trap_ctrl.exc_buf(exc_iillegal_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_iil_c;
|
trap_ctrl.cause_nxt <= trap_iil_c;
|
|
|
|
|
-- exception: 0.11 environment call from M-mode --
|
-- exception: 0.11 environment call from M-mode --
|
elsif (trap_ctrl.exc_buf(exc_m_envcall_c) = '1') then
|
elsif (trap_ctrl.exc_buf(exc_m_envcall_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_menv_c;
|
trap_ctrl.cause_nxt <= trap_menv_c;
|
|
|
-- exception: 0.8 environment call from U-mode --
|
-- exception: 0.8 environment call from U-mode --
|
elsif (trap_ctrl.exc_buf(exc_u_envcall_c) = '1') then
|
elsif (trap_ctrl.exc_buf(exc_u_envcall_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_uenv_c;
|
trap_ctrl.cause_nxt <= trap_uenv_c;
|
|
|
-- exception: 0.3 breakpoint --
|
-- exception: 0.3 breakpoint --
|
elsif (trap_ctrl.exc_buf(exc_break_c) = '1') then
|
elsif (trap_ctrl.exc_buf(exc_break_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_brk_c;
|
trap_ctrl.cause_nxt <= trap_brk_c;
|
|
|
|
|
-- exception: 0.6 store address misaligned -
|
-- exception: 0.6 store address misaligned -
|
elsif (trap_ctrl.exc_buf(exc_salign_c) = '1') then
|
elsif (trap_ctrl.exc_buf(exc_salign_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_sma_c;
|
trap_ctrl.cause_nxt <= trap_sma_c;
|
|
|
-- exception: 0.4 load address misaligned --
|
-- exception: 0.4 load address misaligned --
|
elsif (trap_ctrl.exc_buf(exc_lalign_c) = '1') then
|
elsif (trap_ctrl.exc_buf(exc_lalign_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_lma_c;
|
trap_ctrl.cause_nxt <= trap_lma_c;
|
|
|
-- exception: 0.7 store access fault --
|
-- exception: 0.7 store access fault --
|
elsif (trap_ctrl.exc_buf(exc_saccess_c) = '1') then
|
elsif (trap_ctrl.exc_buf(exc_saccess_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_sbe_c;
|
trap_ctrl.cause_nxt <= trap_sbe_c;
|
|
|
-- exception: 0.5 load access fault --
|
-- exception: 0.5 load access fault --
|
elsif (trap_ctrl.exc_buf(exc_laccess_c) = '1') then
|
elsif (trap_ctrl.exc_buf(exc_laccess_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_lbe_c;
|
trap_ctrl.cause_nxt <= trap_lbe_c;
|
|
|
-- ----------------------------------------------------------------------------------------
|
-- ----------------------------------------------------------------------------------------
|
-- (re-)enter debug mode requests: basically, these are standard traps that have some
|
-- (re-)enter debug mode requests: basically, these are standard traps that have some
|
-- special handling - they have the highest INTERRUPT priority in order to go to debug when requested
|
-- special handling - they have the highest INTERRUPT priority in order to go to debug when requested
|
-- even if other IRQs are pending right now
|
-- even if other IRQs are pending right now
|
-- ----------------------------------------------------------------------------------------
|
-- ----------------------------------------------------------------------------------------
|
|
|
-- hardware trigger (sync) --
|
-- hardware trigger (sync) --
|
elsif (trap_ctrl.exc_buf(exc_db_hw_c) = '1') then
|
elsif (trap_ctrl.exc_buf(exc_db_hw_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_db_hw_c;
|
trap_ctrl.cause_nxt <= trap_db_hw_c;
|
|
|
-- break instruction (sync) --
|
-- break instruction (sync) --
|
elsif (trap_ctrl.exc_buf(exc_db_break_c) = '1') then
|
elsif (trap_ctrl.exc_buf(exc_db_break_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_db_break_c;
|
trap_ctrl.cause_nxt <= trap_db_break_c;
|
|
|
-- async. exceptions / interrupts
|
-- async. exceptions / interrupts
|
|
|
-- external halt request (async) --
|
-- external halt request (async) --
|
elsif (trap_ctrl.irq_buf(irq_db_halt_c) = '1') then
|
elsif (trap_ctrl.irq_buf(irq_db_halt_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_db_halt_c;
|
trap_ctrl.cause_nxt <= trap_db_halt_c;
|
|
|
-- single stepping (async) --
|
-- single stepping (async) --
|
elsif (trap_ctrl.irq_buf(irq_db_step_c) = '1') then
|
elsif (trap_ctrl.irq_buf(irq_db_step_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_db_step_c;
|
trap_ctrl.cause_nxt <= trap_db_step_c;
|
|
|
-- ----------------------------------------------------------------------------------------
|
-- ----------------------------------------------------------------------------------------
|
-- custom FAST interrupts (*asynchronous* exceptions)
|
-- custom FAST interrupts (*asynchronous* exceptions)
|
-- ----------------------------------------------------------------------------------------
|
-- ----------------------------------------------------------------------------------------
|
|
|
-- interrupt: 1.16 fast interrupt channel 0 --
|
-- interrupt: 1.16 fast interrupt channel 0 --
|
elsif (trap_ctrl.irq_buf(irq_firq_0_c) = '1') then
|
elsif (trap_ctrl.irq_buf(irq_firq_0_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_firq0_c;
|
trap_ctrl.cause_nxt <= trap_firq0_c;
|
|
|
-- interrupt: 1.17 fast interrupt channel 1 --
|
-- interrupt: 1.17 fast interrupt channel 1 --
|
elsif (trap_ctrl.irq_buf(irq_firq_1_c) = '1') then
|
elsif (trap_ctrl.irq_buf(irq_firq_1_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_firq1_c;
|
trap_ctrl.cause_nxt <= trap_firq1_c;
|
|
|
-- interrupt: 1.18 fast interrupt channel 2 --
|
-- interrupt: 1.18 fast interrupt channel 2 --
|
elsif (trap_ctrl.irq_buf(irq_firq_2_c) = '1') then
|
elsif (trap_ctrl.irq_buf(irq_firq_2_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_firq2_c;
|
trap_ctrl.cause_nxt <= trap_firq2_c;
|
|
|
-- interrupt: 1.19 fast interrupt channel 3 --
|
-- interrupt: 1.19 fast interrupt channel 3 --
|
elsif (trap_ctrl.irq_buf(irq_firq_3_c) = '1') then
|
elsif (trap_ctrl.irq_buf(irq_firq_3_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_firq3_c;
|
trap_ctrl.cause_nxt <= trap_firq3_c;
|
|
|
-- interrupt: 1.20 fast interrupt channel 4 --
|
-- interrupt: 1.20 fast interrupt channel 4 --
|
elsif (trap_ctrl.irq_buf(irq_firq_4_c) = '1') then
|
elsif (trap_ctrl.irq_buf(irq_firq_4_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_firq4_c;
|
trap_ctrl.cause_nxt <= trap_firq4_c;
|
|
|
-- interrupt: 1.21 fast interrupt channel 5 --
|
-- interrupt: 1.21 fast interrupt channel 5 --
|
elsif (trap_ctrl.irq_buf(irq_firq_5_c) = '1') then
|
elsif (trap_ctrl.irq_buf(irq_firq_5_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_firq5_c;
|
trap_ctrl.cause_nxt <= trap_firq5_c;
|
|
|
-- interrupt: 1.22 fast interrupt channel 6 --
|
-- interrupt: 1.22 fast interrupt channel 6 --
|
elsif (trap_ctrl.irq_buf(irq_firq_6_c) = '1') then
|
elsif (trap_ctrl.irq_buf(irq_firq_6_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_firq6_c;
|
trap_ctrl.cause_nxt <= trap_firq6_c;
|
|
|
-- interrupt: 1.23 fast interrupt channel 7 --
|
-- interrupt: 1.23 fast interrupt channel 7 --
|
elsif (trap_ctrl.irq_buf(irq_firq_7_c) = '1') then
|
elsif (trap_ctrl.irq_buf(irq_firq_7_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_firq7_c;
|
trap_ctrl.cause_nxt <= trap_firq7_c;
|
|
|
-- interrupt: 1.24 fast interrupt channel 8 --
|
-- interrupt: 1.24 fast interrupt channel 8 --
|
elsif (trap_ctrl.irq_buf(irq_firq_8_c) = '1') then
|
elsif (trap_ctrl.irq_buf(irq_firq_8_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_firq8_c;
|
trap_ctrl.cause_nxt <= trap_firq8_c;
|
|
|
-- interrupt: 1.25 fast interrupt channel 9 --
|
-- interrupt: 1.25 fast interrupt channel 9 --
|
elsif (trap_ctrl.irq_buf(irq_firq_9_c) = '1') then
|
elsif (trap_ctrl.irq_buf(irq_firq_9_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_firq9_c;
|
trap_ctrl.cause_nxt <= trap_firq9_c;
|
|
|
-- interrupt: 1.26 fast interrupt channel 10 --
|
-- interrupt: 1.26 fast interrupt channel 10 --
|
elsif (trap_ctrl.irq_buf(irq_firq_10_c) = '1') then
|
elsif (trap_ctrl.irq_buf(irq_firq_10_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_firq10_c;
|
trap_ctrl.cause_nxt <= trap_firq10_c;
|
|
|
-- interrupt: 1.27 fast interrupt channel 11 --
|
-- interrupt: 1.27 fast interrupt channel 11 --
|
elsif (trap_ctrl.irq_buf(irq_firq_11_c) = '1') then
|
elsif (trap_ctrl.irq_buf(irq_firq_11_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_firq11_c;
|
trap_ctrl.cause_nxt <= trap_firq11_c;
|
|
|
-- interrupt: 1.28 fast interrupt channel 12 --
|
-- interrupt: 1.28 fast interrupt channel 12 --
|
elsif (trap_ctrl.irq_buf(irq_firq_12_c) = '1') then
|
elsif (trap_ctrl.irq_buf(irq_firq_12_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_firq12_c;
|
trap_ctrl.cause_nxt <= trap_firq12_c;
|
|
|
-- interrupt: 1.29 fast interrupt channel 13 --
|
-- interrupt: 1.29 fast interrupt channel 13 --
|
elsif (trap_ctrl.irq_buf(irq_firq_13_c) = '1') then
|
elsif (trap_ctrl.irq_buf(irq_firq_13_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_firq13_c;
|
trap_ctrl.cause_nxt <= trap_firq13_c;
|
|
|
-- interrupt: 1.30 fast interrupt channel 14 --
|
-- interrupt: 1.30 fast interrupt channel 14 --
|
elsif (trap_ctrl.irq_buf(irq_firq_14_c) = '1') then
|
elsif (trap_ctrl.irq_buf(irq_firq_14_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_firq14_c;
|
trap_ctrl.cause_nxt <= trap_firq14_c;
|
|
|
-- interrupt: 1.31 fast interrupt channel 15 --
|
-- interrupt: 1.31 fast interrupt channel 15 --
|
elsif (trap_ctrl.irq_buf(irq_firq_15_c) = '1') then
|
elsif (trap_ctrl.irq_buf(irq_firq_15_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_firq15_c;
|
trap_ctrl.cause_nxt <= trap_firq15_c;
|
|
|
-- ----------------------------------------------------------------------------------------
|
-- ----------------------------------------------------------------------------------------
|
-- standard RISC-V interrupts (*asynchronous* exceptions)
|
-- standard RISC-V interrupts (*asynchronous* exceptions)
|
-- ----------------------------------------------------------------------------------------
|
-- ----------------------------------------------------------------------------------------
|
|
|
-- interrupt: 1.11 machine external interrupt (MEI) --
|
-- interrupt: 1.11 machine external interrupt (MEI) --
|
elsif (trap_ctrl.irq_buf(irq_mext_irq_c) = '1') then
|
elsif (trap_ctrl.irq_buf(irq_mext_irq_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_mei_c;
|
trap_ctrl.cause_nxt <= trap_mei_c;
|
|
|
-- interrupt: 1.3 machine SW interrupt (MSI) --
|
-- interrupt: 1.3 machine SW interrupt (MSI) --
|
elsif (trap_ctrl.irq_buf(irq_msw_irq_c) = '1') then
|
elsif (trap_ctrl.irq_buf(irq_msw_irq_c) = '1') then
|
trap_ctrl.cause_nxt <= trap_msi_c;
|
trap_ctrl.cause_nxt <= trap_msi_c;
|
|
|
-- interrupt: 1.7 machine timer interrupt (MTI) --
|
-- interrupt: 1.7 machine timer interrupt (MTI) --
|
else--if (trap_ctrl.irq_buf(irq_mtime_irq_c) = '1') then -- last condition, so NO IF required
|
else--if (trap_ctrl.irq_buf(irq_mtime_irq_c) = '1') then -- last condition, so NO IF required
|
trap_ctrl.cause_nxt <= trap_mti_c;
|
trap_ctrl.cause_nxt <= trap_mti_c;
|
|
|
end if;
|
end if;
|
end process trap_priority;
|
end process trap_priority;
|
|
|
|
|
-- ****************************************************************************************************************************
|
-- ****************************************************************************************************************************
|
-- Control and Status Registers (CSRs)
|
-- Control and Status Registers (CSRs)
|
-- ****************************************************************************************************************************
|
-- ****************************************************************************************************************************
|
|
|
-- Control and Status Registers - Write Data ----------------------------------------------
|
-- Control and Status Registers - Write Data ----------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
csr_write_data: process(execute_engine.i_reg, csr.rdata, rs1_i)
|
csr_write_data: process(execute_engine.i_reg, csr.rdata, rs1_i)
|
variable csr_imm_v : std_ulogic_vector(data_width_c-1 downto 0);
|
variable csr_imm_v : std_ulogic_vector(data_width_c-1 downto 0);
|
begin
|
begin
|
-- tiny ALU to compute CSR write data --
|
-- tiny ALU to compute CSR write data --
|
csr_imm_v := (others => '0');
|
csr_imm_v := (others => '0');
|
csr_imm_v(4 downto 0) := execute_engine.i_reg(19 downto 15); -- uimm5
|
csr_imm_v(4 downto 0) := execute_engine.i_reg(19 downto 15); -- uimm5
|
case execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) is
|
case execute_engine.i_reg(instr_funct3_msb_c downto instr_funct3_lsb_c) is
|
when funct3_csrrw_c => csr.wdata <= rs1_i;
|
when funct3_csrrw_c => csr.wdata <= rs1_i;
|
when funct3_csrrs_c => csr.wdata <= csr.rdata or rs1_i;
|
when funct3_csrrs_c => csr.wdata <= csr.rdata or rs1_i;
|
when funct3_csrrc_c => csr.wdata <= csr.rdata and (not rs1_i);
|
when funct3_csrrc_c => csr.wdata <= csr.rdata and (not rs1_i);
|
when funct3_csrrwi_c => csr.wdata <= csr_imm_v;
|
when funct3_csrrwi_c => csr.wdata <= csr_imm_v;
|
when funct3_csrrsi_c => csr.wdata <= csr.rdata or csr_imm_v;
|
when funct3_csrrsi_c => csr.wdata <= csr.rdata or csr_imm_v;
|
when funct3_csrrci_c => csr.wdata <= csr.rdata and (not csr_imm_v);
|
when funct3_csrrci_c => csr.wdata <= csr.rdata and (not csr_imm_v);
|
when others => csr.wdata <= (others => '-'); -- undefined
|
when others => csr.wdata <= (others => '0'); -- undefined
|
end case;
|
end case;
|
end process csr_write_data;
|
end process csr_write_data;
|
|
|
|
|
-- Control and Status Registers - Write Access --------------------------------------------
|
-- Control and Status Registers - Write Access --------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
csr_write_access: process(rstn_i, clk_i)
|
csr_write_access: process(rstn_i, clk_i)
|
variable cause_v : std_ulogic_vector(6 downto 0);
|
variable cause_v : std_ulogic_vector(6 downto 0);
|
begin
|
begin
|
if (rstn_i = '0') then
|
if (rstn_i = '0') then
|
csr.we <= '0';
|
csr.we <= '0';
|
|
csr.re <= def_rst_val_c;
|
--
|
--
|
csr.mstatus_mie <= '0';
|
csr.mstatus_mie <= '0';
|
csr.mstatus_mpie <= '0';
|
csr.mstatus_mpie <= '0';
|
csr.mstatus_mpp <= '0';
|
csr.mstatus_mpp <= '0';
|
csr.mstatus_tw <= '0';
|
csr.mstatus_tw <= '0';
|
csr.privilege <= priv_mode_m_c; -- start in MACHINE mode
|
csr.privilege <= priv_mode_m_c; -- start in MACHINE mode
|
csr.mie_msie <= def_rst_val_c;
|
csr.mie_msie <= def_rst_val_c;
|
csr.mie_meie <= def_rst_val_c;
|
csr.mie_meie <= def_rst_val_c;
|
csr.mie_mtie <= def_rst_val_c;
|
csr.mie_mtie <= def_rst_val_c;
|
csr.mie_firqe <= (others => def_rst_val_c);
|
csr.mie_firqe <= (others => def_rst_val_c);
|
csr.mtvec <= (others => def_rst_val_c);
|
csr.mtvec <= (others => def_rst_val_c);
|
csr.mscratch <= x"19880704";
|
csr.mscratch <= x"19880704";
|
csr.mepc <= (others => def_rst_val_c);
|
csr.mepc <= (others => def_rst_val_c);
|
csr.mcause <= (others => def_rst_val_c);
|
csr.mcause <= (others => def_rst_val_c);
|
csr.mtval <= (others => def_rst_val_c);
|
csr.mtval <= (others => def_rst_val_c);
|
csr.mip_firq_nclr <= (others => def_rst_val_c);
|
csr.mip_firq_nclr <= (others => def_rst_val_c);
|
--
|
--
|
csr.pmpcfg <= (others => (others => '0'));
|
csr.pmpcfg <= (others => (others => '0'));
|
csr.pmpaddr <= (others => (others => def_rst_val_c));
|
csr.pmpaddr <= (others => (others => def_rst_val_c));
|
--
|
--
|
csr.mhpmevent <= (others => (others => def_rst_val_c));
|
csr.mhpmevent <= (others => (others => def_rst_val_c));
|
--
|
--
|
csr.mcounteren_cy <= def_rst_val_c;
|
csr.mcounteren_cy <= def_rst_val_c;
|
csr.mcounteren_tm <= def_rst_val_c;
|
csr.mcounteren_tm <= def_rst_val_c;
|
csr.mcounteren_ir <= def_rst_val_c;
|
csr.mcounteren_ir <= def_rst_val_c;
|
--
|
--
|
csr.mcountinhibit_cy <= def_rst_val_c;
|
csr.mcountinhibit_cy <= def_rst_val_c;
|
csr.mcountinhibit_ir <= def_rst_val_c;
|
csr.mcountinhibit_ir <= def_rst_val_c;
|
csr.mcountinhibit_hpm <= (others => def_rst_val_c);
|
csr.mcountinhibit_hpm <= (others => def_rst_val_c);
|
--
|
--
|
csr.fflags <= (others => def_rst_val_c);
|
csr.fflags <= (others => def_rst_val_c);
|
csr.frm <= (others => def_rst_val_c);
|
csr.frm <= (others => def_rst_val_c);
|
--
|
--
|
csr.dcsr_ebreakm <= '0';
|
csr.dcsr_ebreakm <= '0';
|
csr.dcsr_ebreaku <= '0';
|
csr.dcsr_ebreaku <= '0';
|
csr.dcsr_step <= '0';
|
csr.dcsr_step <= '0';
|
csr.dcsr_prv <= priv_mode_m_c;
|
csr.dcsr_prv <= priv_mode_m_c;
|
csr.dcsr_cause <= (others => def_rst_val_c);
|
csr.dcsr_cause <= (others => def_rst_val_c);
|
csr.dpc <= (others => def_rst_val_c);
|
csr.dpc <= (others => def_rst_val_c);
|
csr.dscratch0 <= (others => def_rst_val_c);
|
csr.dscratch0 <= (others => def_rst_val_c);
|
--
|
--
|
csr.tdata1_exe <= '0';
|
csr.tdata1_exe <= '0';
|
csr.tdata2 <= (others => def_rst_val_c);
|
csr.tdata2 <= (others => def_rst_val_c);
|
|
|
elsif rising_edge(clk_i) then
|
elsif rising_edge(clk_i) then
|
-- write access? --
|
-- write access? --
|
csr.we <= csr.we_nxt;
|
csr.we <= csr.we_nxt and (not trap_ctrl.exc_buf(exc_iillegal_c)); -- write if not illegal instruction
|
|
csr.re <= csr.re_nxt;
|
|
|
-- defaults --
|
-- defaults --
|
csr.mip_firq_nclr <= (others => '1'); -- active low
|
csr.mip_firq_nclr <= (others => '1'); -- active low
|
|
|
if (CPU_EXTENSION_RISCV_Zicsr = true) then
|
if (CPU_EXTENSION_RISCV_Zicsr = true) then
|
-- --------------------------------------------------------------------------------
|
-- --------------------------------------------------------------------------------
|
-- CSR access by application software
|
-- CSR access by application software
|
-- --------------------------------------------------------------------------------
|
-- --------------------------------------------------------------------------------
|
if (csr.we = '1') and (trap_ctrl.exc_buf(exc_iillegal_c) = '0') then -- manual write access and not illegal instruction
|
if (csr.we = '1') then -- manual write access and not illegal instruction
|
|
|
-- user floating-point CSRs --
|
-- user floating-point CSRs --
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
if (CPU_EXTENSION_RISCV_Zfinx = true) then -- floating point CSR class
|
if (CPU_EXTENSION_RISCV_Zfinx = true) then -- floating point CSR class
|
if (csr.addr(11 downto 2) = csr_class_float_c) then
|
if (csr.addr(11 downto 2) = csr_class_float_c) then
|
if (csr.addr(1 downto 0) = "01") then -- R/W: fflags - floating-point (FPU) exception flags
|
if (csr.addr(1 downto 0) = "01") then -- R/W: fflags - floating-point (FPU) exception flags
|
csr.fflags <= csr.wdata(4 downto 0);
|
csr.fflags <= csr.wdata(4 downto 0);
|
elsif (csr.addr(1 downto 0) = "10") then -- R/W: frm - floating-point (FPU) rounding mode
|
elsif (csr.addr(1 downto 0) = "10") then -- R/W: frm - floating-point (FPU) rounding mode
|
csr.frm <= csr.wdata(2 downto 0);
|
csr.frm <= csr.wdata(2 downto 0);
|
elsif (csr.addr(1 downto 0) = "11") then -- R/W: fcsr - floating-point (FPU) control/status (frm + fflags)
|
elsif (csr.addr(1 downto 0) = "11") then -- R/W: fcsr - floating-point (FPU) control/status (frm + fflags)
|
csr.frm <= csr.wdata(7 downto 5);
|
csr.frm <= csr.wdata(7 downto 5);
|
csr.fflags <= csr.wdata(4 downto 0);
|
csr.fflags <= csr.wdata(4 downto 0);
|
end if;
|
end if;
|
end if;
|
end if;
|
end if;
|
end if;
|
|
|
-- machine trap setup --
|
-- machine trap setup --
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
if (csr.addr(11 downto 3) = csr_class_setup_c) then -- trap setup CSR class
|
if (csr.addr(11 downto 3) = csr_class_setup_c) then -- trap setup CSR class
|
-- R/W: mstatus - machine status register --
|
-- R/W: mstatus - machine status register --
|
if (csr.addr(2 downto 0) = csr_mstatus_c(2 downto 0)) then
|
if (csr.addr(2 downto 0) = csr_mstatus_c(2 downto 0)) then
|
csr.mstatus_mie <= csr.wdata(03);
|
csr.mstatus_mie <= csr.wdata(03);
|
csr.mstatus_mpie <= csr.wdata(07);
|
csr.mstatus_mpie <= csr.wdata(07);
|
if (CPU_EXTENSION_RISCV_U = true) then -- user mode implemented
|
if (CPU_EXTENSION_RISCV_U = true) then -- user mode implemented
|
csr.mstatus_mpp <= csr.wdata(11) or csr.wdata(12); -- everything /= U will fall back to M
|
csr.mstatus_mpp <= csr.wdata(11) or csr.wdata(12); -- everything /= U will fall back to M
|
csr.mstatus_tw <= csr.wdata(21);
|
csr.mstatus_tw <= csr.wdata(21);
|
end if;
|
end if;
|
end if;
|
end if;
|
-- R/W: mie - machine interrupt enable register --
|
-- R/W: mie - machine interrupt enable register --
|
if (csr.addr(2 downto 0) = csr_mie_c(2 downto 0)) then
|
if (csr.addr(2 downto 0) = csr_mie_c(2 downto 0)) then
|
csr.mie_msie <= csr.wdata(03); -- machine SW IRQ enable
|
csr.mie_msie <= csr.wdata(03); -- machine SW IRQ enable
|
csr.mie_mtie <= csr.wdata(07); -- machine TIMER IRQ enable
|
csr.mie_mtie <= csr.wdata(07); -- machine TIMER IRQ enable
|
csr.mie_meie <= csr.wdata(11); -- machine EXT IRQ enable
|
csr.mie_meie <= csr.wdata(11); -- machine EXT IRQ enable
|
csr.mie_firqe <= csr.wdata(31 downto 16); -- fast interrupt channels 0..15
|
csr.mie_firqe <= csr.wdata(31 downto 16); -- fast interrupt channels 0..15
|
end if;
|
end if;
|
-- R/W: mtvec - machine trap-handler base address (for ALL exceptions) --
|
-- R/W: mtvec - machine trap-handler base address (for ALL exceptions) --
|
if (csr.addr(2 downto 0) = csr_mtvec_c(2 downto 0)) then
|
if (csr.addr(2 downto 0) = csr_mtvec_c(2 downto 0)) then
|
csr.mtvec <= csr.wdata(data_width_c-1 downto 2) & "00"; -- mtvec.MODE=0
|
csr.mtvec <= csr.wdata(data_width_c-1 downto 2) & "00"; -- mtvec.MODE=0
|
end if;
|
end if;
|
-- R/W: mcounteren - machine counter enable register --
|
-- R/W: mcounteren - machine counter enable register --
|
if (CPU_EXTENSION_RISCV_U = true) then -- this CSR is hardwired to zero if user mode is not implemented
|
if (CPU_EXTENSION_RISCV_U = true) then -- this CSR is hardwired to zero if user mode is not implemented
|
if (csr.addr(2 downto 0) = csr_mcounteren_c(2 downto 0)) then
|
if (csr.addr(2 downto 0) = csr_mcounteren_c(2 downto 0)) then
|
csr.mcounteren_cy <= csr.wdata(0); -- enable user-level access to cycle[h]
|
csr.mcounteren_cy <= csr.wdata(0); -- enable user-level access to cycle[h]
|
csr.mcounteren_tm <= csr.wdata(1); -- enable user-level access to time[h]
|
csr.mcounteren_tm <= csr.wdata(1); -- enable user-level access to time[h]
|
csr.mcounteren_ir <= csr.wdata(2); -- enable user-level access to instret[h]
|
csr.mcounteren_ir <= csr.wdata(2); -- enable user-level access to instret[h]
|
end if;
|
end if;
|
end if;
|
end if;
|
end if;
|
end if;
|
|
|
-- machine trap handling --
|
-- machine trap handling --
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
if (csr.addr(11 downto 4) = csr_class_trap_c) then -- machine trap handling CSR class
|
if (csr.addr(11 downto 4) = csr_class_trap_c) then -- machine trap handling CSR class
|
-- R/W: mscratch - machine scratch register --
|
-- R/W: mscratch - machine scratch register --
|
if (csr.addr(3 downto 0) = csr_mscratch_c(3 downto 0)) then
|
if (csr.addr(3 downto 0) = csr_mscratch_c(3 downto 0)) then
|
csr.mscratch <= csr.wdata;
|
csr.mscratch <= csr.wdata;
|
end if;
|
end if;
|
-- R/W: mepc - machine exception program counter --
|
-- R/W: mepc - machine exception program counter --
|
if (csr.addr(3 downto 0) = csr_mepc_c(3 downto 0)) then
|
if (csr.addr(3 downto 0) = csr_mepc_c(3 downto 0)) then
|
csr.mepc <= csr.wdata;
|
csr.mepc <= csr.wdata;
|
end if;
|
end if;
|
-- R/W: mcause - machine trap cause --
|
-- R/W: mcause - machine trap cause --
|
if (csr.addr(3 downto 0) = csr_mcause_c(3 downto 0)) then
|
if (csr.addr(3 downto 0) = csr_mcause_c(3 downto 0)) then
|
csr.mcause(csr.mcause'left) <= csr.wdata(31); -- 1: async/interrupt, 0: sync/exception
|
csr.mcause <= csr.wdata(31) & csr.wdata(4 downto 0); -- type + identifier
|
csr.mcause(4 downto 0) <= csr.wdata(4 downto 0); -- identifier
|
|
end if;
|
end if;
|
-- R/W: mip - machine interrupt pending --
|
-- R/W: mip - machine interrupt pending --
|
if (csr.addr(3 downto 0) = csr_mip_c(3 downto 0)) then
|
if (csr.addr(3 downto 0) = csr_mip_c(3 downto 0)) then
|
csr.mip_firq_nclr <= csr.wdata(31 downto 16); -- set low to clear according bit (FIRQs only)
|
csr.mip_firq_nclr <= csr.wdata(31 downto 16); -- set low to clear according bit (FIRQs only)
|
end if;
|
end if;
|
end if;
|
end if;
|
|
|
-- physical memory protection: R/W: pmpcfg* - PMP configuration registers --
|
-- physical memory protection --
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
if (PMP_NUM_REGIONS > 0) then
|
if (PMP_NUM_REGIONS > 0) then
|
|
-- R/W: pmpcfg* - PMP configuration registers --
|
if (csr.addr(11 downto 2) = csr_class_pmpcfg_c) then -- pmp configuration CSR class
|
if (csr.addr(11 downto 2) = csr_class_pmpcfg_c) then -- pmp configuration CSR class
|
for i in 0 to 3 loop -- 3 pmpcfg CSRs
|
for i in 0 to 3 loop -- 3 pmpcfg CSRs
|
if (csr.addr(1 downto 0) = std_ulogic_vector(to_unsigned(i, 2))) then
|
if (csr.addr(1 downto 0) = std_ulogic_vector(to_unsigned(i, 2))) then
|
for j in 0 to 3 loop -- 4 entries per CSR
|
for j in 0 to 3 loop -- 4 entries per CSR
|
if (csr.pmpcfg(i*4+j)(7) = '0') then -- unlocked pmpcfg entry
|
if (csr.pmpcfg(i*4+j)(7) = '0') then -- unlocked pmpcfg entry
|
csr.pmpcfg(i*4+j)(0) <= csr.wdata(j*8+0); -- R - read
|
csr.pmpcfg(i*4+j)(0) <= csr.wdata(j*8+0); -- R - read
|
csr.pmpcfg(i*4+j)(1) <= csr.wdata(j*8+1); -- W - write
|
csr.pmpcfg(i*4+j)(1) <= csr.wdata(j*8+1); -- W - write
|
csr.pmpcfg(i*4+j)(2) <= csr.wdata(j*8+2); -- X - execute
|
csr.pmpcfg(i*4+j)(2) <= csr.wdata(j*8+2); -- X - execute
|
csr.pmpcfg(i*4+j)(3) <= csr.wdata(j*8+3); -- A_L - mode low [TOR-mode only!]
|
csr.pmpcfg(i*4+j)(3) <= csr.wdata(j*8+3); -- A_L - mode low [TOR-mode only!]
|
csr.pmpcfg(i*4+j)(4) <= '0'; -- A_H - mode high [TOR-mode only!]
|
csr.pmpcfg(i*4+j)(4) <= '0'; -- A_H - mode high [TOR-mode only!]
|
csr.pmpcfg(i*4+j)(5) <= '0'; -- reserved
|
csr.pmpcfg(i*4+j)(5) <= '0'; -- reserved
|
csr.pmpcfg(i*4+j)(6) <= '0'; -- reserved
|
csr.pmpcfg(i*4+j)(6) <= '0'; -- reserved
|
csr.pmpcfg(i*4+j)(7) <= csr.wdata(j*8+7); -- L (locked / also enforce in machine-mode)
|
csr.pmpcfg(i*4+j)(7) <= csr.wdata(j*8+7); -- L (locked / also enforce in machine-mode)
|
end if;
|
end if;
|
end loop; -- j (entry)
|
end loop; -- j (entry)
|
end if;
|
end if;
|
end loop; -- i (pmpcfg CSR)
|
end loop; -- i (pmpcfg CSR)
|
end if;
|
end if;
|
end if;
|
-- R/W: pmpaddr* - PMP address registers --
|
|
|
-- physical memory protection: R/W: pmpaddr* - PMP address registers --
|
|
-- --------------------------------------------------------------------
|
|
if (PMP_NUM_REGIONS > 0) then
|
|
if (csr.addr(11 downto 4) = csr_class_pmpaddr_c) then
|
if (csr.addr(11 downto 4) = csr_class_pmpaddr_c) then
|
for i in 0 to PMP_NUM_REGIONS-1 loop
|
for i in 0 to PMP_NUM_REGIONS-1 loop
|
if (csr.addr(3 downto 0) = std_ulogic_vector(to_unsigned(i, 4))) and (csr.pmpcfg(i)(7) = '0') then -- unlocked pmpaddr access
|
if (csr.addr(3 downto 0) = std_ulogic_vector(to_unsigned(i, 4))) and (csr.pmpcfg(i)(7) = '0') then -- unlocked pmpaddr access
|
csr.pmpaddr(i) <= csr.wdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2);
|
csr.pmpaddr(i) <= csr.wdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2);
|
end if;
|
end if;
|
end loop; -- i (PMP regions)
|
end loop; -- i (PMP regions)
|
end if;
|
end if;
|
end if;
|
end if;
|
|
|
-- machine counter setup --
|
-- machine counter setup --
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
if (csr.addr(11 downto 5) = csr_cnt_setup_c) then -- counter configuration CSR class
|
if (csr.addr(11 downto 5) = csr_cnt_setup_c) then -- counter configuration CSR class
|
-- R/W: mcountinhibit - machine counter-inhibit register --
|
-- R/W: mcountinhibit - machine counter-inhibit register --
|
if (csr.addr(4 downto 0) = csr_mcountinhibit_c(4 downto 0)) then
|
if (csr.addr(4 downto 0) = csr_mcountinhibit_c(4 downto 0)) then
|
csr.mcountinhibit_cy <= csr.wdata(0); -- enable auto-increment of [m]cycle[h] counter
|
csr.mcountinhibit_cy <= csr.wdata(0); -- enable auto-increment of [m]cycle[h] counter
|
csr.mcountinhibit_ir <= csr.wdata(2); -- enable auto-increment of [m]instret[h] counter
|
csr.mcountinhibit_ir <= csr.wdata(2); -- enable auto-increment of [m]instret[h] counter
|
if (HPM_NUM_CNTS > 0) and (CPU_EXTENSION_RISCV_Zihpm = true) then -- any HPMs available?
|
if (HPM_NUM_CNTS > 0) and (CPU_EXTENSION_RISCV_Zihpm = true) then -- any HPMs available?
|
csr.mcountinhibit_hpm <= csr.wdata(csr.mcountinhibit_hpm'left+3 downto 3); -- enable auto-increment of [m]hpmcounter*[h] counter
|
csr.mcountinhibit_hpm <= csr.wdata(csr.mcountinhibit_hpm'left+3 downto 3); -- enable auto-increment of [m]hpmcounter*[h] counter
|
end if;
|
end if;
|
end if;
|
end if;
|
-- R/W: mhpmevent - machine performance-monitors event selector --
|
-- R/W: mhpmevent - machine performance-monitors event selector --
|
if (HPM_NUM_CNTS > 0) and (CPU_EXTENSION_RISCV_Zihpm = true) then
|
if (HPM_NUM_CNTS > 0) and (CPU_EXTENSION_RISCV_Zihpm = true) then
|
for i in 0 to HPM_NUM_CNTS-1 loop
|
for i in 0 to HPM_NUM_CNTS-1 loop
|
if (csr.addr(4 downto 0) = std_ulogic_vector(to_unsigned(i+3, 5))) then
|
if (csr.addr(4 downto 0) = std_ulogic_vector(to_unsigned(i+3, 5))) then
|
csr.mhpmevent(i) <= csr.wdata(csr.mhpmevent(i)'left downto 0);
|
csr.mhpmevent(i) <= csr.wdata(csr.mhpmevent(i)'left downto 0);
|
end if;
|
end if;
|
csr.mhpmevent(i)(hpmcnt_event_never_c) <= '0'; -- would be used for "TIME"
|
csr.mhpmevent(i)(hpmcnt_event_never_c) <= '0'; -- would be used for "TIME"
|
end loop; -- i (CSRs)
|
end loop; -- i (CSRs)
|
end if;
|
end if;
|
end if;
|
end if;
|
|
|
-- debug mode CSRs --
|
-- debug mode CSRs --
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
if (CPU_EXTENSION_RISCV_DEBUG = true) then
|
if (CPU_EXTENSION_RISCV_DEBUG = true) then
|
if (csr.addr(11 downto 2) = csr_class_debug_c) then -- debug CSR class
|
if (csr.addr(11 downto 2) = csr_class_debug_c) then -- debug CSR class
|
-- R/W: dcsr - debug mode control and status register --
|
-- R/W: dcsr - debug mode control and status register --
|
if (csr.addr(1 downto 0) = csr_dcsr_c(1 downto 0)) then
|
if (csr.addr(1 downto 0) = csr_dcsr_c(1 downto 0)) then
|
csr.dcsr_ebreakm <= csr.wdata(15);
|
csr.dcsr_ebreakm <= csr.wdata(15);
|
csr.dcsr_step <= csr.wdata(2);
|
csr.dcsr_step <= csr.wdata(2);
|
if (CPU_EXTENSION_RISCV_U = true) then -- user mode implemented
|
if (CPU_EXTENSION_RISCV_U = true) then -- user mode implemented
|
csr.dcsr_ebreaku <= csr.wdata(12);
|
csr.dcsr_ebreaku <= csr.wdata(12);
|
csr.dcsr_prv <= csr.wdata(1) or csr.wdata(0); -- everything /= U will fall back to M
|
csr.dcsr_prv <= csr.wdata(1) or csr.wdata(0); -- everything /= U will fall back to M
|
end if;
|
end if;
|
end if;
|
end if;
|
-- R/W: dpc - debug mode program counter --
|
-- R/W: dpc - debug mode program counter --
|
if (csr.addr(1 downto 0) = csr_dpc_c(1 downto 0)) then
|
if (csr.addr(1 downto 0) = csr_dpc_c(1 downto 0)) then
|
csr.dpc <= csr.wdata(data_width_c-1 downto 1) & '0';
|
csr.dpc <= csr.wdata(data_width_c-1 downto 1) & '0';
|
end if;
|
end if;
|
-- R/W: dscratch0 - debug mode scratch register 0 --
|
-- R/W: dscratch0 - debug mode scratch register 0 --
|
if (csr.addr(1 downto 0) = csr_dscratch0_c(1 downto 0)) then
|
if (csr.addr(1 downto 0) = csr_dscratch0_c(1 downto 0)) then
|
csr.dscratch0 <= csr.wdata;
|
csr.dscratch0 <= csr.wdata;
|
end if;
|
end if;
|
end if;
|
end if;
|
end if;
|
end if;
|
|
|
-- trigger module CSRs - only writable in DEBUG MODE (dmode == 1) --
|
-- trigger module CSRs - only writable in DEBUG MODE (dmode == 1) --
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
if (CPU_EXTENSION_RISCV_DEBUG = true) then
|
if (CPU_EXTENSION_RISCV_DEBUG = true) then
|
if (csr.addr(11 downto 4) = csr_class_trigger_c) then -- trigger CSR class
|
if (csr.addr(11 downto 4) = csr_class_trigger_c) then -- trigger CSR class
|
if (debug_ctrl.running = '1') then -- actual write only in debug mode
|
if (debug_ctrl.running = '1') then -- actual write only in debug mode
|
-- R/W: tdata1 - match control --
|
-- R/W: tdata1 - match control --
|
if (csr.addr(3 downto 0) = csr_tdata1_c(3 downto 0)) then
|
if (csr.addr(3 downto 0) = csr_tdata1_c(3 downto 0)) then
|
csr.tdata1_exe <= csr.wdata(2);
|
csr.tdata1_exe <= csr.wdata(2);
|
end if;
|
end if;
|
-- R/W: tdata2 - address compare --
|
-- R/W: tdata2 - address compare --
|
if (csr.addr(3 downto 0) = csr_tdata2_c(3 downto 0)) then
|
if (csr.addr(3 downto 0) = csr_tdata2_c(3 downto 0)) then
|
csr.tdata2 <= csr.wdata(data_width_c-1 downto 1) & '0';
|
csr.tdata2 <= csr.wdata(data_width_c-1 downto 1) & '0';
|
end if;
|
end if;
|
end if;
|
end if;
|
end if;
|
end if;
|
end if;
|
end if;
|
|
|
|
|
-- --------------------------------------------------------------------------------
|
-- --------------------------------------------------------------------------------
|
-- CSR access by hardware
|
-- CSR access by hardware
|
-- --------------------------------------------------------------------------------
|
-- --------------------------------------------------------------------------------
|
else
|
else
|
|
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
-- floating-point (FPU) exception flags
|
-- floating-point (FPU) exception flags
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
if (CPU_EXTENSION_RISCV_Zfinx = true) and (trap_ctrl.exc_buf(exc_iillegal_c) = '0') then -- no illegal instruction
|
if (CPU_EXTENSION_RISCV_Zfinx = true) and (trap_ctrl.exc_buf(exc_iillegal_c) = '0') then -- no illegal instruction
|
csr.fflags <= csr.fflags or fpu_flags_i; -- accumulate flags ("accrued exception flags")
|
csr.fflags <= csr.fflags or fpu_flags_i; -- accumulate flags ("accrued exception flags")
|
end if;
|
end if;
|
|
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
-- TRAP ENTER: write machine trap cause, PC and trap value register
|
-- TRAP ENTER: write machine trap cause, PC and trap value register
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
if (trap_ctrl.env_start_ack = '1') then -- trap handler starting?
|
if (trap_ctrl.env_start_ack = '1') then -- trap handler starting?
|
|
|
-- normal trap entry: write mcause, mepc and mtval --
|
-- normal trap entry: write mcause, mepc and mtval --
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
if (CPU_EXTENSION_RISCV_DEBUG = false) or ((trap_ctrl.cause(5) = '0') and (debug_ctrl.running = '0')) then
|
if (CPU_EXTENSION_RISCV_DEBUG = false) or ((trap_ctrl.cause(5) = '0') and (debug_ctrl.running = '0')) then
|
|
|
-- trap cause ID code --
|
-- trap cause ID code --
|
csr.mcause(csr.mcause'left) <= trap_ctrl.cause(trap_ctrl.cause'left); -- 1: interrupt, 0: exception
|
csr.mcause <= trap_ctrl.cause(trap_ctrl.cause'left) & trap_ctrl.cause(4 downto 0); -- type + identifier
|
csr.mcause(4 downto 0) <= trap_ctrl.cause(4 downto 0); -- identifier
|
|
|
|
-- trap PC --
|
-- trap PC --
|
if (trap_ctrl.cause(trap_ctrl.cause'left) = '1') then -- for INTERRUPTS (async source)
|
if (trap_ctrl.cause(trap_ctrl.cause'left) = '1') then -- for INTERRUPTS (async source)
|
csr.mepc <= execute_engine.pc(data_width_c-1 downto 1) & '0'; -- this is the CURRENT pc = interrupted instruction
|
csr.mepc <= execute_engine.pc(data_width_c-1 downto 1) & '0'; -- this is the CURRENT pc = interrupted instruction
|
else -- for sync. EXCEPTIONS (sync source)
|
else -- for sync. EXCEPTIONS (sync source)
|
csr.mepc <= execute_engine.pc_last(data_width_c-1 downto 1) & '0'; -- this is the LAST pc = last executed instruction
|
csr.mepc <= execute_engine.pc_last(data_width_c-1 downto 1) & '0'; -- this is the LAST pc = last executed instruction
|
end if;
|
end if;
|
|
|
-- trap value --
|
-- trap value --
|
cause_v := trap_ctrl.cause;
|
cause_v := trap_ctrl.cause;
|
cause_v(5) := '0'; -- bit 5 is always zero here (= normal trapping), so we do not need to check that again
|
cause_v(5) := '0'; -- bit 5 is always zero here (= normal trapping / no debug-mode-entry), so we do not need to check that again
|
case cause_v is
|
case cause_v is
|
when trap_ima_c | trap_iba_c => -- misaligned instruction address OR instruction access error
|
when trap_ima_c | trap_iba_c => -- misaligned instruction address OR instruction access error
|
csr.mtval <= execute_engine.pc(data_width_c-1 downto 1) & '0'; -- address of faulting instruction
|
csr.mtval <= execute_engine.pc(data_width_c-1 downto 1) & '0'; -- address of faulting instruction
|
when trap_brk_c => -- breakpoint
|
|
csr.mtval <= execute_engine.pc_last(data_width_c-1 downto 1) & '0'; -- address of breakpoint instruction
|
|
when trap_lma_c | trap_lbe_c | trap_sma_c | trap_sbe_c => -- misaligned load/store address OR load/store access error
|
when trap_lma_c | trap_lbe_c | trap_sma_c | trap_sbe_c => -- misaligned load/store address OR load/store access error
|
csr.mtval <= mar_i; -- faulting data access address
|
csr.mtval <= mar_i; -- faulting data access address
|
when trap_iil_c => -- illegal instruction
|
when trap_iil_c => -- illegal instruction
|
csr.mtval <= execute_engine.i_reg_last; -- faulting instruction itself
|
csr.mtval <= execute_engine.i_reg_last; -- faulting instruction word (decompressed if C-instruction)
|
when others => -- everything else including all interrupts
|
when others => -- everything else including all interrupts
|
csr.mtval <= (others => '0');
|
csr.mtval <= (others => '0');
|
end case;
|
end case;
|
|
|
end if;
|
end if;
|
|
|
-- DEBUG MODE (trap) enter: write dpc and dcsr --
|
-- DEBUG MODE (trap) enter: write dpc and dcsr --
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
if (CPU_EXTENSION_RISCV_DEBUG = true) and (trap_ctrl.cause(5) = '1') and (debug_ctrl.running = '0') then
|
if (CPU_EXTENSION_RISCV_DEBUG = true) and (trap_ctrl.cause(5) = '1') and (debug_ctrl.running = '0') then
|
|
|
-- trap cause ID code --
|
-- trap cause ID code --
|
csr.dcsr_cause <= trap_ctrl.cause(2 downto 0); -- why did we enter debug mode?
|
csr.dcsr_cause <= trap_ctrl.cause(2 downto 0); -- why did we enter debug mode?
|
|
|
-- current privilege mode when debug mode was entered --
|
-- current privilege mode when debug mode was entered --
|
csr.dcsr_prv <= csr.privilege;
|
csr.dcsr_prv <= csr.privilege;
|
|
|
-- trap PC --
|
-- trap PC --
|
if (trap_ctrl.cause(trap_ctrl.cause'left) = '1') then -- for INTERRUPTS (async source)
|
if (trap_ctrl.cause(trap_ctrl.cause'left) = '1') then -- for INTERRUPTS (async source)
|
csr.dpc <= execute_engine.pc(data_width_c-1 downto 1) & '0'; -- this is the CURRENT pc = interrupted instruction
|
csr.dpc <= execute_engine.pc(data_width_c-1 downto 1) & '0'; -- this is the CURRENT pc = interrupted instruction
|
else -- for sync. EXCEPTIONS (sync source)
|
else -- for sync. EXCEPTIONS (sync source)
|
csr.dpc <= execute_engine.pc_last(data_width_c-1 downto 1) & '0'; -- this is the LAST pc = last executed instruction
|
csr.dpc <= execute_engine.pc_last(data_width_c-1 downto 1) & '0'; -- this is the LAST pc = last executed instruction
|
end if;
|
end if;
|
|
|
end if;
|
end if;
|
|
|
end if;
|
end if;
|
|
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
-- mstatus: context switch
|
-- mstatus: context switch
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
-- ENTER: trap handler starting
|
-- ENTER: trap handler starting
|
if (trap_ctrl.env_start_ack = '1') then -- trap handler starting?
|
if (trap_ctrl.env_start_ack = '1') then -- trap handler starting?
|
if (CPU_EXTENSION_RISCV_DEBUG = false) or -- normal trapping (debug mode NOT implemented)
|
if (CPU_EXTENSION_RISCV_DEBUG = false) or -- normal trapping (debug mode NOT implemented)
|
((debug_ctrl.running = '0') and (trap_ctrl.cause(5) = '0')) then -- not IN debug mode and not ENTERING debug mode
|
((debug_ctrl.running = '0') and (trap_ctrl.cause(5) = '0')) then -- not IN debug mode and not ENTERING debug mode
|
csr.mstatus_mie <= '0'; -- disable interrupts
|
csr.mstatus_mie <= '0'; -- disable interrupts
|
csr.mstatus_mpie <= csr.mstatus_mie; -- buffer previous mie state
|
csr.mstatus_mpie <= csr.mstatus_mie; -- buffer previous mie state
|
if (CPU_EXTENSION_RISCV_U = true) then -- user mode implemented
|
if (CPU_EXTENSION_RISCV_U = true) then -- user mode implemented
|
csr.privilege <= priv_mode_m_c; -- execute trap in machine mode
|
csr.privilege <= priv_mode_m_c; -- execute trap in machine mode
|
csr.mstatus_mpp <= csr.privilege; -- backup previous privilege mode
|
csr.mstatus_mpp <= csr.privilege; -- backup previous privilege mode
|
end if;
|
end if;
|
end if;
|
end if;
|
|
|
-- EXIT: return from trap
|
-- EXIT: return from trap
|
elsif (trap_ctrl.env_end = '1') then
|
elsif (trap_ctrl.env_end = '1') then
|
if (CPU_EXTENSION_RISCV_DEBUG = true) and (debug_ctrl.running = '1') then -- return from debug mode
|
if (CPU_EXTENSION_RISCV_DEBUG = true) and (debug_ctrl.running = '1') then -- return from debug mode
|
if (CPU_EXTENSION_RISCV_U = true) then -- user mode implemented
|
if (CPU_EXTENSION_RISCV_U = true) then -- user mode implemented
|
csr.privilege <= csr.dcsr_prv;
|
csr.privilege <= csr.dcsr_prv;
|
end if;
|
end if;
|
else -- return from "normal trap"
|
else -- return from "normal trap"
|
csr.mstatus_mie <= csr.mstatus_mpie; -- restore global IRQ enable flag
|
csr.mstatus_mie <= csr.mstatus_mpie; -- restore global IRQ enable flag
|
csr.mstatus_mpie <= '1';
|
csr.mstatus_mpie <= '1';
|
if (CPU_EXTENSION_RISCV_U = true) then -- user mode implemented
|
if (CPU_EXTENSION_RISCV_U = true) then -- user mode implemented
|
csr.privilege <= csr.mstatus_mpp; -- go back to previous privilege mode
|
csr.privilege <= csr.mstatus_mpp; -- go back to previous privilege mode
|
csr.mstatus_mpp <= '0'; -- MRET has to clear mstatus.MPP
|
csr.mstatus_mpp <= '0'; -- MRET has to clear mstatus.MPP
|
end if;
|
end if;
|
end if;
|
end if;
|
end if;
|
end if;
|
|
|
end if; -- /hardware csr access
|
end if; -- /hardware csr access
|
end if;
|
end if;
|
end if;
|
end if;
|
end process csr_write_access;
|
end process csr_write_access;
|
|
|
-- effective privilege mode is M when in debug mode --
|
-- effective privilege mode is M when in debug mode --
|
csr.privilege_eff <= priv_mode_m_c when (CPU_EXTENSION_RISCV_DEBUG = true) and (debug_ctrl.running = '1') else csr.privilege;
|
csr.privilege_eff <= priv_mode_m_c when (CPU_EXTENSION_RISCV_DEBUG = true) and (debug_ctrl.running = '1') else csr.privilege;
|
|
|
-- PMP output to bus unit --
|
-- PMP output to bus unit --
|
pmp_output:
|
pmp_output:
|
for i in 0 to PMP_NUM_REGIONS-1 generate
|
for i in 0 to PMP_NUM_REGIONS-1 generate
|
pmp_addr_o(i)(data_width_c-1 downto index_size_f(PMP_MIN_GRANULARITY)) <= csr.pmpaddr(i); -- physical address
|
pmp_addr_o(i)(data_width_c-1 downto index_size_f(PMP_MIN_GRANULARITY)) <= csr.pmpaddr(i); -- physical address
|
pmp_ctrl_o(i) <= csr.pmpcfg(i);
|
pmp_ctrl_o(i) <= csr.pmpcfg(i);
|
end generate;
|
end generate;
|
|
|
|
|
-- Control and Status Registers - Read Access ---------------------------------------------
|
-- Control and Status Registers - Read Access ---------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
csr_read_access: process(rstn_i, clk_i)
|
csr_read_access: process(clk_i)
|
variable csr_addr_v : std_ulogic_vector(11 downto 0);
|
variable csr_addr_v : std_ulogic_vector(11 downto 0);
|
begin
|
begin
|
if rising_edge(clk_i) then
|
if rising_edge(clk_i) then
|
csr.rdata <= (others => '0'); -- default output, unimplemented CSRs are hardwired to zero
|
csr.rdata <= (others => '0'); -- default output, unimplemented CSRs read as zero
|
if (CPU_EXTENSION_RISCV_Zicsr = true) then
|
if (CPU_EXTENSION_RISCV_Zicsr = true) then
|
|
|
|
-- AND-gate CSR read address: csr.rdata is zero if csr.re is not set --
|
|
if (csr.re = '1') then
|
csr_addr_v(11 downto 10) := csr.addr(11 downto 10);
|
csr_addr_v(11 downto 10) := csr.addr(11 downto 10);
|
csr_addr_v(09 downto 08) := (others => csr.addr(8)); -- !!! WARNING: MACHINE (11) and USER (00) CSRs ONLY !!!
|
csr_addr_v(09 downto 08) := (others => csr.addr(8)); -- !!! WARNING: MACHINE (11) and USER (00) CSRS ONLY !!!
|
csr_addr_v(07 downto 00) := csr.addr(07 downto 00);
|
csr_addr_v(07 downto 00) := csr.addr(07 downto 00);
|
|
else -- reduce switching activity if not accessed
|
|
csr_addr_v := (others => '0'); -- = csr_zero_c
|
|
end if;
|
case csr_addr_v is
|
case csr_addr_v is
|
|
|
|
-- hardware-only CSRs --
|
|
-- --------------------------------------------------------------------
|
|
-- when csr_zero_c => -- zero (r/-): always returns zero, only relevant for hardware-access, not visible to ISA
|
|
-- csr.rdata <= (others => '0');
|
|
|
-- floating-point CSRs --
|
-- floating-point CSRs --
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
when csr_fflags_c => -- fflags (r/w): floating-point (FPU) exception flags
|
when csr_fflags_c => -- fflags (r/w): floating-point (FPU) exception flags
|
if (CPU_EXTENSION_RISCV_Zfinx) then csr.rdata(4 downto 0) <= csr.fflags; else NULL; end if;
|
if (CPU_EXTENSION_RISCV_Zfinx) then csr.rdata(4 downto 0) <= csr.fflags; else NULL; end if;
|
when csr_frm_c => -- frm (r/w): floating-point (FPU) rounding mode
|
when csr_frm_c => -- frm (r/w): floating-point (FPU) rounding mode
|
if (CPU_EXTENSION_RISCV_Zfinx) then csr.rdata(2 downto 0) <= csr.frm; else NULL; end if;
|
if (CPU_EXTENSION_RISCV_Zfinx) then csr.rdata(2 downto 0) <= csr.frm; else NULL; end if;
|
when csr_fcsr_c => -- fcsr (r/w): floating-point (FPU) control/status (frm + fflags)
|
when csr_fcsr_c => -- fcsr (r/w): floating-point (FPU) control/status (frm + fflags)
|
if (CPU_EXTENSION_RISCV_Zfinx) then csr.rdata(7 downto 0) <= csr.frm & csr.fflags; else NULL; end if;
|
if (CPU_EXTENSION_RISCV_Zfinx) then csr.rdata(7 downto 0) <= csr.frm & csr.fflags; else NULL; end if;
|
|
|
-- machine trap setup --
|
-- machine trap setup --
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
when csr_mstatus_c => -- mstatus (r/w): machine status register
|
when csr_mstatus_c => -- mstatus (r/w): machine status register - low word
|
csr.rdata(03) <= csr.mstatus_mie; -- MIE
|
csr.rdata(03) <= csr.mstatus_mie; -- MIE
|
csr.rdata(07) <= csr.mstatus_mpie; -- MPIE
|
csr.rdata(07) <= csr.mstatus_mpie; -- MPIE
|
csr.rdata(12 downto 11) <= (others => csr.mstatus_mpp); -- MPP: machine previous privilege mode
|
csr.rdata(12 downto 11) <= (others => csr.mstatus_mpp); -- MPP: machine previous privilege mode
|
csr.rdata(21) <= csr.mstatus_tw and bool_to_ulogic_f(CPU_EXTENSION_RISCV_U); -- TW
|
csr.rdata(21) <= csr.mstatus_tw and bool_to_ulogic_f(CPU_EXTENSION_RISCV_U); -- TW
|
-- when csr_mstatush_c => -- mstatush (r/w): machine status register - high, implemented but always zero
|
-- when csr_mstatush_c => -- mstatush (r/w): machine status register - high word, implemented but always zero
|
-- csr.rdata <= (others => '0');
|
-- csr.rdata <= (others => '0');
|
when csr_misa_c => -- misa (r/-): ISA and extensions
|
when csr_misa_c => -- misa (r/-): ISA and extensions
|
csr.rdata(00) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_A); -- A CPU extension
|
csr.rdata(00) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_A); -- A CPU extension
|
csr.rdata(01) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_B); -- B CPU extension
|
csr.rdata(01) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_B); -- B CPU extension
|
csr.rdata(02) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_C); -- C CPU extension
|
csr.rdata(02) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_C); -- C CPU extension
|
csr.rdata(04) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_E); -- E CPU extension
|
csr.rdata(04) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_E); -- E CPU extension
|
csr.rdata(08) <= not bool_to_ulogic_f(CPU_EXTENSION_RISCV_E); -- I CPU extension (if not E)
|
csr.rdata(08) <= not bool_to_ulogic_f(CPU_EXTENSION_RISCV_E); -- I CPU extension (if not E)
|
csr.rdata(12) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_M); -- M CPU extension
|
csr.rdata(12) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_M); -- M CPU extension
|
csr.rdata(20) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_U); -- U CPU extension
|
csr.rdata(20) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_U); -- U CPU extension
|
csr.rdata(23) <= '1'; -- X CPU extension (non-standard extensions / NEORV32-specific)
|
csr.rdata(23) <= '1'; -- X CPU extension (non-standard extensions / NEORV32-specific)
|
csr.rdata(30) <= '1'; -- 32-bit architecture (MXL lo)
|
csr.rdata(30) <= '1'; -- 32-bit architecture (MXL lo)
|
csr.rdata(31) <= '0'; -- 32-bit architecture (MXL hi)
|
csr.rdata(31) <= '0'; -- 32-bit architecture (MXL hi)
|
when csr_mie_c => -- mie (r/w): machine interrupt-enable register
|
when csr_mie_c => -- mie (r/w): machine interrupt-enable register
|
csr.rdata(03) <= csr.mie_msie; -- machine software IRQ enable
|
csr.rdata(03) <= csr.mie_msie; -- machine software IRQ enable
|
csr.rdata(07) <= csr.mie_mtie; -- machine timer IRQ enable
|
csr.rdata(07) <= csr.mie_mtie; -- machine timer IRQ enable
|
csr.rdata(11) <= csr.mie_meie; -- machine external IRQ enable
|
csr.rdata(11) <= csr.mie_meie; -- machine external IRQ enable
|
csr.rdata(31 downto 16) <= csr.mie_firqe;
|
csr.rdata(31 downto 16) <= csr.mie_firqe;
|
when csr_mtvec_c => -- mtvec (r/w): machine trap-handler base address (for ALL exceptions)
|
when csr_mtvec_c => -- mtvec (r/w): machine trap-handler base address (for ALL exceptions)
|
csr.rdata <= csr.mtvec(data_width_c-1 downto 2) & "00"; -- mtvec.MODE=0
|
csr.rdata <= csr.mtvec(data_width_c-1 downto 2) & "00"; -- mtvec.MODE=0
|
when csr_mcounteren_c => -- mcounteren (r/w): machine counter enable register, hardwired to zero if user mode is not implemented
|
when csr_mcounteren_c => -- mcounteren (r/w): machine counter enable register, hardwired to zero if user mode is not implemented
|
csr.rdata(0) <= csr.mcounteren_cy and bool_to_ulogic_f(CPU_EXTENSION_RISCV_U); -- enable user-level access to cycle[h]
|
csr.rdata(0) <= csr.mcounteren_cy and bool_to_ulogic_f(CPU_EXTENSION_RISCV_U); -- enable user-level access to cycle[h]
|
csr.rdata(1) <= csr.mcounteren_tm and bool_to_ulogic_f(CPU_EXTENSION_RISCV_U); -- enable user-level access to time[h]
|
csr.rdata(1) <= csr.mcounteren_tm and bool_to_ulogic_f(CPU_EXTENSION_RISCV_U); -- enable user-level access to time[h]
|
csr.rdata(2) <= csr.mcounteren_ir and bool_to_ulogic_f(CPU_EXTENSION_RISCV_U); -- enable user-level access to instret[h]
|
csr.rdata(2) <= csr.mcounteren_ir and bool_to_ulogic_f(CPU_EXTENSION_RISCV_U); -- enable user-level access to instret[h]
|
|
|
-- machine trap handling --
|
-- machine trap handling --
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
when csr_mscratch_c => -- mscratch (r/w): machine scratch register
|
when csr_mscratch_c => -- mscratch (r/w): machine scratch register
|
csr.rdata <= csr.mscratch;
|
csr.rdata <= csr.mscratch;
|
when csr_mepc_c => -- mepc (r/w): machine exception program counter
|
when csr_mepc_c => -- mepc (r/w): machine exception program counter
|
csr.rdata <= csr.mepc(data_width_c-1 downto 1) & '0';
|
csr.rdata <= csr.mepc(data_width_c-1 downto 1) & '0';
|
when csr_mcause_c => -- mcause (r/w): machine trap cause
|
when csr_mcause_c => -- mcause (r/w): machine trap cause
|
csr.rdata(31) <= csr.mcause(csr.mcause'left);
|
csr.rdata(31) <= csr.mcause(5);
|
csr.rdata(csr.mcause'left-1 downto 0) <= csr.mcause(csr.mcause'left-1 downto 0);
|
csr.rdata(4 downto 0) <= csr.mcause(4 downto 0);
|
when csr_mtval_c => -- mtval (r/-): machine bad address or instruction
|
when csr_mtval_c => -- mtval (r/-): machine bad address or instruction
|
csr.rdata <= csr.mtval;
|
csr.rdata <= csr.mtval;
|
when csr_mip_c => -- mip (r/w): machine interrupt pending
|
when csr_mip_c => -- mip (r/w): machine interrupt pending
|
csr.rdata(03) <= trap_ctrl.irq_buf(irq_msw_irq_c);
|
csr.rdata(03) <= trap_ctrl.irq_buf(irq_msw_irq_c);
|
csr.rdata(07) <= trap_ctrl.irq_buf(irq_mtime_irq_c);
|
csr.rdata(07) <= trap_ctrl.irq_buf(irq_mtime_irq_c);
|
csr.rdata(11) <= trap_ctrl.irq_buf(irq_mext_irq_c);
|
csr.rdata(11) <= trap_ctrl.irq_buf(irq_mext_irq_c);
|
csr.rdata(31 downto 16) <= trap_ctrl.irq_buf(irq_firq_15_c downto irq_firq_0_c);
|
csr.rdata(31 downto 16) <= trap_ctrl.irq_buf(irq_firq_15_c downto irq_firq_0_c);
|
|
|
-- physical memory protection - configuration (r/w) --
|
-- physical memory protection - configuration (r/w) --
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
when csr_pmpcfg0_c =>
|
when csr_pmpcfg0_c =>
|
if (PMP_NUM_REGIONS > 0) then
|
if (PMP_NUM_REGIONS > 0) then
|
if (PMP_NUM_REGIONS > 00) then csr.rdata(07 downto 00) <= csr.pmpcfg(00); end if;
|
if (PMP_NUM_REGIONS > 00) then csr.rdata(07 downto 00) <= csr.pmpcfg(00); end if;
|
if (PMP_NUM_REGIONS > 01) then csr.rdata(15 downto 08) <= csr.pmpcfg(01); end if;
|
if (PMP_NUM_REGIONS > 01) then csr.rdata(15 downto 08) <= csr.pmpcfg(01); end if;
|
if (PMP_NUM_REGIONS > 02) then csr.rdata(23 downto 16) <= csr.pmpcfg(02); end if;
|
if (PMP_NUM_REGIONS > 02) then csr.rdata(23 downto 16) <= csr.pmpcfg(02); end if;
|
if (PMP_NUM_REGIONS > 03) then csr.rdata(31 downto 24) <= csr.pmpcfg(03); end if;
|
if (PMP_NUM_REGIONS > 03) then csr.rdata(31 downto 24) <= csr.pmpcfg(03); end if;
|
else NULL; end if;
|
else NULL; end if;
|
when csr_pmpcfg1_c =>
|
when csr_pmpcfg1_c =>
|
if (PMP_NUM_REGIONS > 4) then
|
if (PMP_NUM_REGIONS > 4) then
|
if (PMP_NUM_REGIONS > 04) then csr.rdata(07 downto 00) <= csr.pmpcfg(04); end if;
|
if (PMP_NUM_REGIONS > 04) then csr.rdata(07 downto 00) <= csr.pmpcfg(04); end if;
|
if (PMP_NUM_REGIONS > 05) then csr.rdata(15 downto 08) <= csr.pmpcfg(05); end if;
|
if (PMP_NUM_REGIONS > 05) then csr.rdata(15 downto 08) <= csr.pmpcfg(05); end if;
|
if (PMP_NUM_REGIONS > 06) then csr.rdata(23 downto 16) <= csr.pmpcfg(06); end if;
|
if (PMP_NUM_REGIONS > 06) then csr.rdata(23 downto 16) <= csr.pmpcfg(06); end if;
|
if (PMP_NUM_REGIONS > 07) then csr.rdata(31 downto 24) <= csr.pmpcfg(07); end if;
|
if (PMP_NUM_REGIONS > 07) then csr.rdata(31 downto 24) <= csr.pmpcfg(07); end if;
|
else NULL; end if;
|
else NULL; end if;
|
when csr_pmpcfg2_c =>
|
when csr_pmpcfg2_c =>
|
if (PMP_NUM_REGIONS > 8) then
|
if (PMP_NUM_REGIONS > 8) then
|
if (PMP_NUM_REGIONS > 08) then csr.rdata(07 downto 00) <= csr.pmpcfg(08); end if;
|
if (PMP_NUM_REGIONS > 08) then csr.rdata(07 downto 00) <= csr.pmpcfg(08); end if;
|
if (PMP_NUM_REGIONS > 09) then csr.rdata(15 downto 08) <= csr.pmpcfg(09); end if;
|
if (PMP_NUM_REGIONS > 09) then csr.rdata(15 downto 08) <= csr.pmpcfg(09); end if;
|
if (PMP_NUM_REGIONS > 10) then csr.rdata(23 downto 16) <= csr.pmpcfg(10); end if;
|
if (PMP_NUM_REGIONS > 10) then csr.rdata(23 downto 16) <= csr.pmpcfg(10); end if;
|
if (PMP_NUM_REGIONS > 11) then csr.rdata(31 downto 24) <= csr.pmpcfg(11); end if;
|
if (PMP_NUM_REGIONS > 11) then csr.rdata(31 downto 24) <= csr.pmpcfg(11); end if;
|
else NULL; end if;
|
else NULL; end if;
|
when csr_pmpcfg3_c =>
|
when csr_pmpcfg3_c =>
|
if (PMP_NUM_REGIONS > 12) then
|
if (PMP_NUM_REGIONS > 12) then
|
if (PMP_NUM_REGIONS > 12) then csr.rdata(07 downto 00) <= csr.pmpcfg(12); end if;
|
if (PMP_NUM_REGIONS > 12) then csr.rdata(07 downto 00) <= csr.pmpcfg(12); end if;
|
if (PMP_NUM_REGIONS > 13) then csr.rdata(15 downto 08) <= csr.pmpcfg(13); end if;
|
if (PMP_NUM_REGIONS > 13) then csr.rdata(15 downto 08) <= csr.pmpcfg(13); end if;
|
if (PMP_NUM_REGIONS > 14) then csr.rdata(23 downto 16) <= csr.pmpcfg(14); end if;
|
if (PMP_NUM_REGIONS > 14) then csr.rdata(23 downto 16) <= csr.pmpcfg(14); end if;
|
if (PMP_NUM_REGIONS > 15) then csr.rdata(31 downto 24) <= csr.pmpcfg(15); end if;
|
if (PMP_NUM_REGIONS > 15) then csr.rdata(31 downto 24) <= csr.pmpcfg(15); end if;
|
else NULL; end if;
|
else NULL; end if;
|
|
|
-- physical memory protection - addresses (r/w) --
|
-- physical memory protection - addresses (r/w) --
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
when csr_pmpaddr0_c => if (PMP_NUM_REGIONS > 00) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(00); else NULL; end if;
|
when csr_pmpaddr0_c => if (PMP_NUM_REGIONS > 00) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(00); else NULL; end if;
|
when csr_pmpaddr1_c => if (PMP_NUM_REGIONS > 01) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(01); else NULL; end if;
|
when csr_pmpaddr1_c => if (PMP_NUM_REGIONS > 01) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(01); else NULL; end if;
|
when csr_pmpaddr2_c => if (PMP_NUM_REGIONS > 02) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(02); else NULL; end if;
|
when csr_pmpaddr2_c => if (PMP_NUM_REGIONS > 02) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(02); else NULL; end if;
|
when csr_pmpaddr3_c => if (PMP_NUM_REGIONS > 03) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(03); else NULL; end if;
|
when csr_pmpaddr3_c => if (PMP_NUM_REGIONS > 03) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(03); else NULL; end if;
|
when csr_pmpaddr4_c => if (PMP_NUM_REGIONS > 04) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(04); else NULL; end if;
|
when csr_pmpaddr4_c => if (PMP_NUM_REGIONS > 04) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(04); else NULL; end if;
|
when csr_pmpaddr5_c => if (PMP_NUM_REGIONS > 05) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(05); else NULL; end if;
|
when csr_pmpaddr5_c => if (PMP_NUM_REGIONS > 05) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(05); else NULL; end if;
|
when csr_pmpaddr6_c => if (PMP_NUM_REGIONS > 06) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(06); else NULL; end if;
|
when csr_pmpaddr6_c => if (PMP_NUM_REGIONS > 06) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(06); else NULL; end if;
|
when csr_pmpaddr7_c => if (PMP_NUM_REGIONS > 07) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(07); else NULL; end if;
|
when csr_pmpaddr7_c => if (PMP_NUM_REGIONS > 07) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(07); else NULL; end if;
|
when csr_pmpaddr8_c => if (PMP_NUM_REGIONS > 08) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(08); else NULL; end if;
|
when csr_pmpaddr8_c => if (PMP_NUM_REGIONS > 08) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(08); else NULL; end if;
|
when csr_pmpaddr9_c => if (PMP_NUM_REGIONS > 09) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(09); else NULL; end if;
|
when csr_pmpaddr9_c => if (PMP_NUM_REGIONS > 09) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(09); else NULL; end if;
|
when csr_pmpaddr10_c => if (PMP_NUM_REGIONS > 10) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(10); else NULL; end if;
|
when csr_pmpaddr10_c => if (PMP_NUM_REGIONS > 10) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(10); else NULL; end if;
|
when csr_pmpaddr11_c => if (PMP_NUM_REGIONS > 11) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(11); else NULL; end if;
|
when csr_pmpaddr11_c => if (PMP_NUM_REGIONS > 11) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(11); else NULL; end if;
|
when csr_pmpaddr12_c => if (PMP_NUM_REGIONS > 12) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(12); else NULL; end if;
|
when csr_pmpaddr12_c => if (PMP_NUM_REGIONS > 12) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(12); else NULL; end if;
|
when csr_pmpaddr13_c => if (PMP_NUM_REGIONS > 13) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(13); else NULL; end if;
|
when csr_pmpaddr13_c => if (PMP_NUM_REGIONS > 13) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(13); else NULL; end if;
|
when csr_pmpaddr14_c => if (PMP_NUM_REGIONS > 14) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(14); else NULL; end if;
|
when csr_pmpaddr14_c => if (PMP_NUM_REGIONS > 14) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(14); else NULL; end if;
|
when csr_pmpaddr15_c => if (PMP_NUM_REGIONS > 15) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(15); else NULL; end if;
|
when csr_pmpaddr15_c => if (PMP_NUM_REGIONS > 15) then csr.rdata(data_width_c-3 downto index_size_f(PMP_MIN_GRANULARITY)-2) <= csr.pmpaddr(15); else NULL; end if;
|
|
|
-- machine counter setup --
|
-- machine counter setup --
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
when csr_mcountinhibit_c => -- mcountinhibit (r/w): machine counter-inhibit register
|
when csr_mcountinhibit_c => -- mcountinhibit (r/w): machine counter-inhibit register
|
csr.rdata(0) <= csr.mcountinhibit_cy; -- enable auto-increment of [m]cycle[h] counter
|
csr.rdata(0) <= csr.mcountinhibit_cy; -- enable auto-increment of [m]cycle[h] counter
|
csr.rdata(2) <= csr.mcountinhibit_ir; -- enable auto-increment of [m]instret[h] counter
|
csr.rdata(2) <= csr.mcountinhibit_ir; -- enable auto-increment of [m]instret[h] counter
|
if (HPM_NUM_CNTS > 0) and (CPU_EXTENSION_RISCV_Zihpm = true) then -- any HPMs available?
|
if (HPM_NUM_CNTS > 0) and (CPU_EXTENSION_RISCV_Zihpm = true) then -- any HPMs available?
|
csr.rdata(csr.mcountinhibit_hpm'left+3 downto 3) <= csr.mcountinhibit_hpm; -- enable auto-increment of [m]hpmcounterx[h] counter
|
csr.rdata(csr.mcountinhibit_hpm'left+3 downto 3) <= csr.mcountinhibit_hpm; -- enable auto-increment of [m]hpmcounterx[h] counter
|
end if;
|
end if;
|
|
|
-- machine performance-monitoring event selector (r/w) --
|
-- machine performance-monitoring event selector (r/w) --
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
when csr_mhpmevent3_c => if (HPM_NUM_CNTS > 00) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(00); else NULL; end if;
|
when csr_mhpmevent3_c => if (HPM_NUM_CNTS > 00) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(00); else NULL; end if;
|
when csr_mhpmevent4_c => if (HPM_NUM_CNTS > 01) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(01); else NULL; end if;
|
when csr_mhpmevent4_c => if (HPM_NUM_CNTS > 01) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(01); else NULL; end if;
|
when csr_mhpmevent5_c => if (HPM_NUM_CNTS > 02) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(02); else NULL; end if;
|
when csr_mhpmevent5_c => if (HPM_NUM_CNTS > 02) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(02); else NULL; end if;
|
when csr_mhpmevent6_c => if (HPM_NUM_CNTS > 03) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(03); else NULL; end if;
|
when csr_mhpmevent6_c => if (HPM_NUM_CNTS > 03) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(03); else NULL; end if;
|
when csr_mhpmevent7_c => if (HPM_NUM_CNTS > 04) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(04); else NULL; end if;
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when csr_mhpmevent7_c => if (HPM_NUM_CNTS > 04) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(04); else NULL; end if;
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when csr_mhpmevent8_c => if (HPM_NUM_CNTS > 05) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(05); else NULL; end if;
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when csr_mhpmevent8_c => if (HPM_NUM_CNTS > 05) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(05); else NULL; end if;
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when csr_mhpmevent9_c => if (HPM_NUM_CNTS > 06) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(06); else NULL; end if;
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when csr_mhpmevent9_c => if (HPM_NUM_CNTS > 06) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(06); else NULL; end if;
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when csr_mhpmevent10_c => if (HPM_NUM_CNTS > 07) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(07); else NULL; end if;
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when csr_mhpmevent10_c => if (HPM_NUM_CNTS > 07) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(07); else NULL; end if;
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when csr_mhpmevent11_c => if (HPM_NUM_CNTS > 08) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(08); else NULL; end if;
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when csr_mhpmevent11_c => if (HPM_NUM_CNTS > 08) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(08); else NULL; end if;
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when csr_mhpmevent12_c => if (HPM_NUM_CNTS > 09) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(09); else NULL; end if;
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when csr_mhpmevent12_c => if (HPM_NUM_CNTS > 09) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(09); else NULL; end if;
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when csr_mhpmevent13_c => if (HPM_NUM_CNTS > 10) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(10); else NULL; end if;
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when csr_mhpmevent13_c => if (HPM_NUM_CNTS > 10) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(10); else NULL; end if;
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when csr_mhpmevent14_c => if (HPM_NUM_CNTS > 11) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(11); else NULL; end if;
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when csr_mhpmevent14_c => if (HPM_NUM_CNTS > 11) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(11); else NULL; end if;
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when csr_mhpmevent15_c => if (HPM_NUM_CNTS > 12) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(12); else NULL; end if;
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when csr_mhpmevent15_c => if (HPM_NUM_CNTS > 12) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(12); else NULL; end if;
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when csr_mhpmevent16_c => if (HPM_NUM_CNTS > 13) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(13); else NULL; end if;
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when csr_mhpmevent16_c => if (HPM_NUM_CNTS > 13) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(13); else NULL; end if;
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when csr_mhpmevent17_c => if (HPM_NUM_CNTS > 14) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(14); else NULL; end if;
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when csr_mhpmevent17_c => if (HPM_NUM_CNTS > 14) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(14); else NULL; end if;
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when csr_mhpmevent18_c => if (HPM_NUM_CNTS > 15) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(15); else NULL; end if;
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when csr_mhpmevent18_c => if (HPM_NUM_CNTS > 15) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(15); else NULL; end if;
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when csr_mhpmevent19_c => if (HPM_NUM_CNTS > 16) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(16); else NULL; end if;
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when csr_mhpmevent19_c => if (HPM_NUM_CNTS > 16) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(16); else NULL; end if;
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when csr_mhpmevent20_c => if (HPM_NUM_CNTS > 17) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(17); else NULL; end if;
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when csr_mhpmevent20_c => if (HPM_NUM_CNTS > 17) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(17); else NULL; end if;
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when csr_mhpmevent21_c => if (HPM_NUM_CNTS > 18) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(18); else NULL; end if;
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when csr_mhpmevent21_c => if (HPM_NUM_CNTS > 18) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(18); else NULL; end if;
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when csr_mhpmevent22_c => if (HPM_NUM_CNTS > 19) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(19); else NULL; end if;
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when csr_mhpmevent22_c => if (HPM_NUM_CNTS > 19) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(19); else NULL; end if;
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when csr_mhpmevent23_c => if (HPM_NUM_CNTS > 20) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(20); else NULL; end if;
|
when csr_mhpmevent23_c => if (HPM_NUM_CNTS > 20) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(20); else NULL; end if;
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when csr_mhpmevent24_c => if (HPM_NUM_CNTS > 21) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(21); else NULL; end if;
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when csr_mhpmevent24_c => if (HPM_NUM_CNTS > 21) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(21); else NULL; end if;
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when csr_mhpmevent25_c => if (HPM_NUM_CNTS > 22) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(22); else NULL; end if;
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when csr_mhpmevent25_c => if (HPM_NUM_CNTS > 22) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(22); else NULL; end if;
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when csr_mhpmevent26_c => if (HPM_NUM_CNTS > 23) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(23); else NULL; end if;
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when csr_mhpmevent26_c => if (HPM_NUM_CNTS > 23) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(23); else NULL; end if;
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when csr_mhpmevent27_c => if (HPM_NUM_CNTS > 24) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(24); else NULL; end if;
|
when csr_mhpmevent27_c => if (HPM_NUM_CNTS > 24) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(24); else NULL; end if;
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when csr_mhpmevent28_c => if (HPM_NUM_CNTS > 25) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(25); else NULL; end if;
|
when csr_mhpmevent28_c => if (HPM_NUM_CNTS > 25) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(25); else NULL; end if;
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when csr_mhpmevent29_c => if (HPM_NUM_CNTS > 26) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(26); else NULL; end if;
|
when csr_mhpmevent29_c => if (HPM_NUM_CNTS > 26) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(26); else NULL; end if;
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when csr_mhpmevent30_c => if (HPM_NUM_CNTS > 27) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(27); else NULL; end if;
|
when csr_mhpmevent30_c => if (HPM_NUM_CNTS > 27) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(27); else NULL; end if;
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when csr_mhpmevent31_c => if (HPM_NUM_CNTS > 28) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(28); else NULL; end if;
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when csr_mhpmevent31_c => if (HPM_NUM_CNTS > 28) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmevent_rd(28); else NULL; end if;
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|
|
-- counters and timers --
|
-- counters and timers --
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
when csr_cycle_c | csr_mcycle_c => -- [m]cycle (r/w): Cycle counter LOW
|
when csr_cycle_c | csr_mcycle_c => -- [m]cycle (r/w): Cycle counter LOW
|
if (cpu_cnt_lo_width_c > 0) and (CPU_EXTENSION_RISCV_Zicntr) then csr.rdata(cpu_cnt_lo_width_c-1 downto 0) <= csr.mcycle(cpu_cnt_lo_width_c-1 downto 0); else NULL; end if;
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if (cpu_cnt_lo_width_c > 0) and (CPU_EXTENSION_RISCV_Zicntr) then csr.rdata(cpu_cnt_lo_width_c-1 downto 0) <= csr.mcycle(cpu_cnt_lo_width_c-1 downto 0); else NULL; end if;
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when csr_cycleh_c | csr_mcycleh_c => -- [m]cycleh (r/w): Cycle counter HIGH
|
when csr_cycleh_c | csr_mcycleh_c => -- [m]cycleh (r/w): Cycle counter HIGH
|
if (cpu_cnt_hi_width_c > 0) and (CPU_EXTENSION_RISCV_Zicntr) then csr.rdata(cpu_cnt_hi_width_c-1 downto 0) <= csr.mcycleh(cpu_cnt_hi_width_c-1 downto 0); else NULL; end if;
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if (cpu_cnt_hi_width_c > 0) and (CPU_EXTENSION_RISCV_Zicntr) then csr.rdata(cpu_cnt_hi_width_c-1 downto 0) <= csr.mcycleh(cpu_cnt_hi_width_c-1 downto 0); else NULL; end if;
|
|
|
when csr_instret_c | csr_minstret_c => -- [m]instret (r/w): Instructions-retired counter LOW
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when csr_instret_c | csr_minstret_c => -- [m]instret (r/w): Instructions-retired counter LOW
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if (cpu_cnt_lo_width_c > 0) and (CPU_EXTENSION_RISCV_Zicntr) then csr.rdata(cpu_cnt_lo_width_c-1 downto 0) <= csr.minstret(cpu_cnt_lo_width_c-1 downto 0); else NULL; end if;
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if (cpu_cnt_lo_width_c > 0) and (CPU_EXTENSION_RISCV_Zicntr) then csr.rdata(cpu_cnt_lo_width_c-1 downto 0) <= csr.minstret(cpu_cnt_lo_width_c-1 downto 0); else NULL; end if;
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when csr_instreth_c | csr_minstreth_c => -- [m]instreth (r/w): Instructions-retired counter HIGH
|
when csr_instreth_c | csr_minstreth_c => -- [m]instreth (r/w): Instructions-retired counter HIGH
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if (cpu_cnt_hi_width_c > 0) and (CPU_EXTENSION_RISCV_Zicntr) then csr.rdata(cpu_cnt_hi_width_c-1 downto 0) <= csr.minstreth(cpu_cnt_hi_width_c-1 downto 0); else NULL; end if;
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if (cpu_cnt_hi_width_c > 0) and (CPU_EXTENSION_RISCV_Zicntr) then csr.rdata(cpu_cnt_hi_width_c-1 downto 0) <= csr.minstreth(cpu_cnt_hi_width_c-1 downto 0); else NULL; end if;
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|
|
when csr_time_c => -- time (r/-): System time LOW (from MTIME unit)
|
when csr_time_c => -- time (r/-): System time LOW (from MTIME unit)
|
if (CPU_EXTENSION_RISCV_Zicntr) then csr.rdata <= time_i(31 downto 00); else NULL; end if;
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if (CPU_EXTENSION_RISCV_Zicntr) then csr.rdata <= time_i(31 downto 00); else NULL; end if;
|
when csr_timeh_c => -- timeh (r/-): System time HIGH (from MTIME unit)
|
when csr_timeh_c => -- timeh (r/-): System time HIGH (from MTIME unit)
|
if (CPU_EXTENSION_RISCV_Zicntr) then csr.rdata <= time_i(63 downto 32); else NULL; end if;
|
if (CPU_EXTENSION_RISCV_Zicntr) then csr.rdata <= time_i(63 downto 32); else NULL; end if;
|
|
|
-- hardware performance counters --
|
-- hardware performance counters --
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
-- low word (r/w) --
|
-- low word (r/w) --
|
when csr_mhpmcounter3_c | csr_hpmcounter3_c => if (HPM_NUM_CNTS > 00) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(00); else NULL; end if;
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when csr_mhpmcounter3_c | csr_hpmcounter3_c => if (HPM_NUM_CNTS > 00) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(00); else NULL; end if;
|
when csr_mhpmcounter4_c | csr_hpmcounter4_c => if (HPM_NUM_CNTS > 01) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(01); else NULL; end if;
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when csr_mhpmcounter4_c | csr_hpmcounter4_c => if (HPM_NUM_CNTS > 01) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(01); else NULL; end if;
|
when csr_mhpmcounter5_c | csr_hpmcounter5_c => if (HPM_NUM_CNTS > 02) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(02); else NULL; end if;
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when csr_mhpmcounter5_c | csr_hpmcounter5_c => if (HPM_NUM_CNTS > 02) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(02); else NULL; end if;
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when csr_mhpmcounter6_c | csr_hpmcounter6_c => if (HPM_NUM_CNTS > 03) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(03); else NULL; end if;
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when csr_mhpmcounter6_c | csr_hpmcounter6_c => if (HPM_NUM_CNTS > 03) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(03); else NULL; end if;
|
when csr_mhpmcounter7_c | csr_hpmcounter7_c => if (HPM_NUM_CNTS > 04) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(04); else NULL; end if;
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when csr_mhpmcounter7_c | csr_hpmcounter7_c => if (HPM_NUM_CNTS > 04) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(04); else NULL; end if;
|
when csr_mhpmcounter8_c | csr_hpmcounter8_c => if (HPM_NUM_CNTS > 05) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(05); else NULL; end if;
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when csr_mhpmcounter8_c | csr_hpmcounter8_c => if (HPM_NUM_CNTS > 05) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(05); else NULL; end if;
|
when csr_mhpmcounter9_c | csr_hpmcounter9_c => if (HPM_NUM_CNTS > 06) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(06); else NULL; end if;
|
when csr_mhpmcounter9_c | csr_hpmcounter9_c => if (HPM_NUM_CNTS > 06) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(06); else NULL; end if;
|
when csr_mhpmcounter10_c | csr_hpmcounter10_c => if (HPM_NUM_CNTS > 07) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(07); else NULL; end if;
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when csr_mhpmcounter10_c | csr_hpmcounter10_c => if (HPM_NUM_CNTS > 07) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(07); else NULL; end if;
|
when csr_mhpmcounter11_c | csr_hpmcounter11_c => if (HPM_NUM_CNTS > 08) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(08); else NULL; end if;
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when csr_mhpmcounter11_c | csr_hpmcounter11_c => if (HPM_NUM_CNTS > 08) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(08); else NULL; end if;
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when csr_mhpmcounter12_c | csr_hpmcounter12_c => if (HPM_NUM_CNTS > 09) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(09); else NULL; end if;
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when csr_mhpmcounter12_c | csr_hpmcounter12_c => if (HPM_NUM_CNTS > 09) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(09); else NULL; end if;
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when csr_mhpmcounter13_c | csr_hpmcounter13_c => if (HPM_NUM_CNTS > 10) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(10); else NULL; end if;
|
when csr_mhpmcounter13_c | csr_hpmcounter13_c => if (HPM_NUM_CNTS > 10) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(10); else NULL; end if;
|
when csr_mhpmcounter14_c | csr_hpmcounter14_c => if (HPM_NUM_CNTS > 11) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(11); else NULL; end if;
|
when csr_mhpmcounter14_c | csr_hpmcounter14_c => if (HPM_NUM_CNTS > 11) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(11); else NULL; end if;
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when csr_mhpmcounter15_c | csr_hpmcounter15_c => if (HPM_NUM_CNTS > 12) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(12); else NULL; end if;
|
when csr_mhpmcounter15_c | csr_hpmcounter15_c => if (HPM_NUM_CNTS > 12) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(12); else NULL; end if;
|
when csr_mhpmcounter16_c | csr_hpmcounter16_c => if (HPM_NUM_CNTS > 13) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(13); else NULL; end if;
|
when csr_mhpmcounter16_c | csr_hpmcounter16_c => if (HPM_NUM_CNTS > 13) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(13); else NULL; end if;
|
when csr_mhpmcounter17_c | csr_hpmcounter17_c => if (HPM_NUM_CNTS > 14) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(14); else NULL; end if;
|
when csr_mhpmcounter17_c | csr_hpmcounter17_c => if (HPM_NUM_CNTS > 14) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(14); else NULL; end if;
|
when csr_mhpmcounter18_c | csr_hpmcounter18_c => if (HPM_NUM_CNTS > 15) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(15); else NULL; end if;
|
when csr_mhpmcounter18_c | csr_hpmcounter18_c => if (HPM_NUM_CNTS > 15) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(15); else NULL; end if;
|
when csr_mhpmcounter19_c | csr_hpmcounter19_c => if (HPM_NUM_CNTS > 16) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(16); else NULL; end if;
|
when csr_mhpmcounter19_c | csr_hpmcounter19_c => if (HPM_NUM_CNTS > 16) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(16); else NULL; end if;
|
when csr_mhpmcounter20_c | csr_hpmcounter20_c => if (HPM_NUM_CNTS > 17) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(17); else NULL; end if;
|
when csr_mhpmcounter20_c | csr_hpmcounter20_c => if (HPM_NUM_CNTS > 17) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(17); else NULL; end if;
|
when csr_mhpmcounter21_c | csr_hpmcounter21_c => if (HPM_NUM_CNTS > 18) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(18); else NULL; end if;
|
when csr_mhpmcounter21_c | csr_hpmcounter21_c => if (HPM_NUM_CNTS > 18) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(18); else NULL; end if;
|
when csr_mhpmcounter22_c | csr_hpmcounter22_c => if (HPM_NUM_CNTS > 19) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(19); else NULL; end if;
|
when csr_mhpmcounter22_c | csr_hpmcounter22_c => if (HPM_NUM_CNTS > 19) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(19); else NULL; end if;
|
when csr_mhpmcounter23_c | csr_hpmcounter23_c => if (HPM_NUM_CNTS > 20) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(20); else NULL; end if;
|
when csr_mhpmcounter23_c | csr_hpmcounter23_c => if (HPM_NUM_CNTS > 20) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(20); else NULL; end if;
|
when csr_mhpmcounter24_c | csr_hpmcounter24_c => if (HPM_NUM_CNTS > 21) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(21); else NULL; end if;
|
when csr_mhpmcounter24_c | csr_hpmcounter24_c => if (HPM_NUM_CNTS > 21) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(21); else NULL; end if;
|
when csr_mhpmcounter25_c | csr_hpmcounter25_c => if (HPM_NUM_CNTS > 22) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(22); else NULL; end if;
|
when csr_mhpmcounter25_c | csr_hpmcounter25_c => if (HPM_NUM_CNTS > 22) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(22); else NULL; end if;
|
when csr_mhpmcounter26_c | csr_hpmcounter26_c => if (HPM_NUM_CNTS > 23) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(23); else NULL; end if;
|
when csr_mhpmcounter26_c | csr_hpmcounter26_c => if (HPM_NUM_CNTS > 23) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(23); else NULL; end if;
|
when csr_mhpmcounter27_c | csr_hpmcounter27_c => if (HPM_NUM_CNTS > 24) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(24); else NULL; end if;
|
when csr_mhpmcounter27_c | csr_hpmcounter27_c => if (HPM_NUM_CNTS > 24) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(24); else NULL; end if;
|
when csr_mhpmcounter28_c | csr_hpmcounter28_c => if (HPM_NUM_CNTS > 25) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(25); else NULL; end if;
|
when csr_mhpmcounter28_c | csr_hpmcounter28_c => if (HPM_NUM_CNTS > 25) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(25); else NULL; end if;
|
when csr_mhpmcounter29_c | csr_hpmcounter29_c => if (HPM_NUM_CNTS > 26) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(26); else NULL; end if;
|
when csr_mhpmcounter29_c | csr_hpmcounter29_c => if (HPM_NUM_CNTS > 26) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(26); else NULL; end if;
|
when csr_mhpmcounter30_c | csr_hpmcounter30_c => if (HPM_NUM_CNTS > 27) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(27); else NULL; end if;
|
when csr_mhpmcounter30_c | csr_hpmcounter30_c => if (HPM_NUM_CNTS > 27) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(27); else NULL; end if;
|
when csr_mhpmcounter31_c | csr_hpmcounter31_c => if (HPM_NUM_CNTS > 28) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(28); else NULL; end if;
|
when csr_mhpmcounter31_c | csr_hpmcounter31_c => if (HPM_NUM_CNTS > 28) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounter_rd(28); else NULL; end if;
|
-- high word (r/w) --
|
-- high word (r/w) --
|
when csr_mhpmcounter3h_c | csr_hpmcounter3h_c => if (HPM_NUM_CNTS > 00) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(00); else NULL; end if;
|
when csr_mhpmcounter3h_c | csr_hpmcounter3h_c => if (HPM_NUM_CNTS > 00) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(00); else NULL; end if;
|
when csr_mhpmcounter4h_c | csr_hpmcounter4h_c => if (HPM_NUM_CNTS > 01) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(01); else NULL; end if;
|
when csr_mhpmcounter4h_c | csr_hpmcounter4h_c => if (HPM_NUM_CNTS > 01) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(01); else NULL; end if;
|
when csr_mhpmcounter5h_c | csr_hpmcounter5h_c => if (HPM_NUM_CNTS > 02) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(02); else NULL; end if;
|
when csr_mhpmcounter5h_c | csr_hpmcounter5h_c => if (HPM_NUM_CNTS > 02) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(02); else NULL; end if;
|
when csr_mhpmcounter6h_c | csr_hpmcounter6h_c => if (HPM_NUM_CNTS > 03) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(03); else NULL; end if;
|
when csr_mhpmcounter6h_c | csr_hpmcounter6h_c => if (HPM_NUM_CNTS > 03) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(03); else NULL; end if;
|
when csr_mhpmcounter7h_c | csr_hpmcounter7h_c => if (HPM_NUM_CNTS > 04) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(04); else NULL; end if;
|
when csr_mhpmcounter7h_c | csr_hpmcounter7h_c => if (HPM_NUM_CNTS > 04) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(04); else NULL; end if;
|
when csr_mhpmcounter8h_c | csr_hpmcounter8h_c => if (HPM_NUM_CNTS > 05) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(05); else NULL; end if;
|
when csr_mhpmcounter8h_c | csr_hpmcounter8h_c => if (HPM_NUM_CNTS > 05) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(05); else NULL; end if;
|
when csr_mhpmcounter9h_c | csr_hpmcounter9h_c => if (HPM_NUM_CNTS > 06) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(06); else NULL; end if;
|
when csr_mhpmcounter9h_c | csr_hpmcounter9h_c => if (HPM_NUM_CNTS > 06) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(06); else NULL; end if;
|
when csr_mhpmcounter10h_c | csr_hpmcounter10h_c => if (HPM_NUM_CNTS > 07) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(07); else NULL; end if;
|
when csr_mhpmcounter10h_c | csr_hpmcounter10h_c => if (HPM_NUM_CNTS > 07) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(07); else NULL; end if;
|
when csr_mhpmcounter11h_c | csr_hpmcounter11h_c => if (HPM_NUM_CNTS > 08) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(08); else NULL; end if;
|
when csr_mhpmcounter11h_c | csr_hpmcounter11h_c => if (HPM_NUM_CNTS > 08) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(08); else NULL; end if;
|
when csr_mhpmcounter12h_c | csr_hpmcounter12h_c => if (HPM_NUM_CNTS > 09) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(09); else NULL; end if;
|
when csr_mhpmcounter12h_c | csr_hpmcounter12h_c => if (HPM_NUM_CNTS > 09) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(09); else NULL; end if;
|
when csr_mhpmcounter13h_c | csr_hpmcounter13h_c => if (HPM_NUM_CNTS > 10) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(10); else NULL; end if;
|
when csr_mhpmcounter13h_c | csr_hpmcounter13h_c => if (HPM_NUM_CNTS > 10) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(10); else NULL; end if;
|
when csr_mhpmcounter14h_c | csr_hpmcounter14h_c => if (HPM_NUM_CNTS > 11) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(11); else NULL; end if;
|
when csr_mhpmcounter14h_c | csr_hpmcounter14h_c => if (HPM_NUM_CNTS > 11) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(11); else NULL; end if;
|
when csr_mhpmcounter15h_c | csr_hpmcounter15h_c => if (HPM_NUM_CNTS > 12) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(12); else NULL; end if;
|
when csr_mhpmcounter15h_c | csr_hpmcounter15h_c => if (HPM_NUM_CNTS > 12) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(12); else NULL; end if;
|
when csr_mhpmcounter16h_c | csr_hpmcounter16h_c => if (HPM_NUM_CNTS > 13) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(13); else NULL; end if;
|
when csr_mhpmcounter16h_c | csr_hpmcounter16h_c => if (HPM_NUM_CNTS > 13) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(13); else NULL; end if;
|
when csr_mhpmcounter17h_c | csr_hpmcounter17h_c => if (HPM_NUM_CNTS > 14) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(14); else NULL; end if;
|
when csr_mhpmcounter17h_c | csr_hpmcounter17h_c => if (HPM_NUM_CNTS > 14) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(14); else NULL; end if;
|
when csr_mhpmcounter18h_c | csr_hpmcounter18h_c => if (HPM_NUM_CNTS > 15) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(15); else NULL; end if;
|
when csr_mhpmcounter18h_c | csr_hpmcounter18h_c => if (HPM_NUM_CNTS > 15) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(15); else NULL; end if;
|
when csr_mhpmcounter19h_c | csr_hpmcounter19h_c => if (HPM_NUM_CNTS > 16) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(16); else NULL; end if;
|
when csr_mhpmcounter19h_c | csr_hpmcounter19h_c => if (HPM_NUM_CNTS > 16) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(16); else NULL; end if;
|
when csr_mhpmcounter20h_c | csr_hpmcounter20h_c => if (HPM_NUM_CNTS > 17) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(17); else NULL; end if;
|
when csr_mhpmcounter20h_c | csr_hpmcounter20h_c => if (HPM_NUM_CNTS > 17) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(17); else NULL; end if;
|
when csr_mhpmcounter21h_c | csr_hpmcounter21h_c => if (HPM_NUM_CNTS > 18) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(18); else NULL; end if;
|
when csr_mhpmcounter21h_c | csr_hpmcounter21h_c => if (HPM_NUM_CNTS > 18) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(18); else NULL; end if;
|
when csr_mhpmcounter22h_c | csr_hpmcounter22h_c => if (HPM_NUM_CNTS > 19) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(19); else NULL; end if;
|
when csr_mhpmcounter22h_c | csr_hpmcounter22h_c => if (HPM_NUM_CNTS > 19) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(19); else NULL; end if;
|
when csr_mhpmcounter23h_c | csr_hpmcounter23h_c => if (HPM_NUM_CNTS > 20) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(20); else NULL; end if;
|
when csr_mhpmcounter23h_c | csr_hpmcounter23h_c => if (HPM_NUM_CNTS > 20) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(20); else NULL; end if;
|
when csr_mhpmcounter24h_c | csr_hpmcounter24h_c => if (HPM_NUM_CNTS > 21) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(21); else NULL; end if;
|
when csr_mhpmcounter24h_c | csr_hpmcounter24h_c => if (HPM_NUM_CNTS > 21) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(21); else NULL; end if;
|
when csr_mhpmcounter25h_c | csr_hpmcounter25h_c => if (HPM_NUM_CNTS > 22) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(22); else NULL; end if;
|
when csr_mhpmcounter25h_c | csr_hpmcounter25h_c => if (HPM_NUM_CNTS > 22) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(22); else NULL; end if;
|
when csr_mhpmcounter26h_c | csr_hpmcounter26h_c => if (HPM_NUM_CNTS > 23) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(23); else NULL; end if;
|
when csr_mhpmcounter26h_c | csr_hpmcounter26h_c => if (HPM_NUM_CNTS > 23) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(23); else NULL; end if;
|
when csr_mhpmcounter27h_c | csr_hpmcounter27h_c => if (HPM_NUM_CNTS > 24) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(24); else NULL; end if;
|
when csr_mhpmcounter27h_c | csr_hpmcounter27h_c => if (HPM_NUM_CNTS > 24) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(24); else NULL; end if;
|
when csr_mhpmcounter28h_c | csr_hpmcounter28h_c => if (HPM_NUM_CNTS > 25) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(25); else NULL; end if;
|
when csr_mhpmcounter28h_c | csr_hpmcounter28h_c => if (HPM_NUM_CNTS > 25) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(25); else NULL; end if;
|
when csr_mhpmcounter29h_c | csr_hpmcounter29h_c => if (HPM_NUM_CNTS > 26) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(26); else NULL; end if;
|
when csr_mhpmcounter29h_c | csr_hpmcounter29h_c => if (HPM_NUM_CNTS > 26) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(26); else NULL; end if;
|
when csr_mhpmcounter30h_c | csr_hpmcounter30h_c => if (HPM_NUM_CNTS > 27) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(27); else NULL; end if;
|
when csr_mhpmcounter30h_c | csr_hpmcounter30h_c => if (HPM_NUM_CNTS > 27) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(27); else NULL; end if;
|
when csr_mhpmcounter31h_c | csr_hpmcounter31h_c => if (HPM_NUM_CNTS > 28) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(28); else NULL; end if;
|
when csr_mhpmcounter31h_c | csr_hpmcounter31h_c => if (HPM_NUM_CNTS > 28) and (CPU_EXTENSION_RISCV_Zihpm) then csr.rdata <= csr.mhpmcounterh_rd(28); else NULL; end if;
|
|
|
-- machine information registers --
|
-- machine information registers --
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
-- when csr_mvendorid_c => csr.rdata <= (others => '0'); -- mvendorid (r/-): vendor ID, implemented but always zero
|
-- when csr_mvendorid_c => csr.rdata <= (others => '0'); -- mvendorid (r/-): vendor ID, implemented but always zero
|
when csr_marchid_c => csr.rdata(4 downto 0) <= "10011"; -- marchid (r/-): arch ID - official RISC-V open-source arch ID
|
when csr_marchid_c => csr.rdata(4 downto 0) <= "10011"; -- marchid (r/-): arch ID - official RISC-V open-source arch ID
|
when csr_mimpid_c => csr.rdata <= hw_version_c; -- mimpid (r/-): implementation ID -- NEORV32 hardware version
|
when csr_mimpid_c => csr.rdata <= hw_version_c; -- mimpid (r/-): implementation ID -- NEORV32 hardware version
|
when csr_mhartid_c => csr.rdata <= std_ulogic_vector(to_unsigned(HW_THREAD_ID, 32)); -- mhartid (r/-): hardware thread ID
|
when csr_mhartid_c => csr.rdata <= std_ulogic_vector(to_unsigned(HW_THREAD_ID, 32)); -- mhartid (r/-): hardware thread ID
|
-- when csr_mconfigptr_c => csr.rdata <= (others => '0'); -- mconfigptr (r/-): machine configuration pointer register, implemented but always zero
|
-- when csr_mconfigptr_c => csr.rdata <= (others => '0'); -- mconfigptr (r/-): machine configuration pointer register, implemented but always zero
|
|
|
-- debug mode CSRs --
|
-- debug mode CSRs --
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
when csr_dcsr_c => if (CPU_EXTENSION_RISCV_DEBUG) then csr.rdata <= csr.dcsr_rd; else NULL; end if; -- dcsr (r/w): debug mode control and status
|
when csr_dcsr_c => if (CPU_EXTENSION_RISCV_DEBUG) then csr.rdata <= csr.dcsr_rd; else NULL; end if; -- dcsr (r/w): debug mode control and status
|
when csr_dpc_c => if (CPU_EXTENSION_RISCV_DEBUG) then csr.rdata <= csr.dpc; else NULL; end if; -- dpc (r/w): debug mode program counter
|
when csr_dpc_c => if (CPU_EXTENSION_RISCV_DEBUG) then csr.rdata <= csr.dpc; else NULL; end if; -- dpc (r/w): debug mode program counter
|
when csr_dscratch0_c => if (CPU_EXTENSION_RISCV_DEBUG) then csr.rdata <= csr.dscratch0; else NULL; end if; -- dscratch0 (r/w): debug mode scratch register 0
|
when csr_dscratch0_c => if (CPU_EXTENSION_RISCV_DEBUG) then csr.rdata <= csr.dscratch0; else NULL; end if; -- dscratch0 (r/w): debug mode scratch register 0
|
|
|
-- trigger module CSRs --
|
-- trigger module CSRs --
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
-- when csr_tselect_c => if (CPU_EXTENSION_RISCV_DEBUG) then csr.rdata <= (others => '0'); else NULL; end if; -- tselect (r/w): always zero = only 1 trigger available
|
-- when csr_tselect_c => if (CPU_EXTENSION_RISCV_DEBUG) then csr.rdata <= (others => '0'); else NULL; end if; -- tselect (r/w): always zero = only 1 trigger available
|
when csr_tdata1_c => if (CPU_EXTENSION_RISCV_DEBUG) then csr.rdata <= csr.tdata1_rd; else NULL; end if; -- tdata1 (r/w): match control
|
when csr_tdata1_c => if (CPU_EXTENSION_RISCV_DEBUG) then csr.rdata <= csr.tdata1_rd; else NULL; end if; -- tdata1 (r/w): match control
|
when csr_tdata2_c => if (CPU_EXTENSION_RISCV_DEBUG) then csr.rdata <= csr.tdata2; else NULL; end if; -- tdata2 (r/w): address-compare
|
when csr_tdata2_c => if (CPU_EXTENSION_RISCV_DEBUG) then csr.rdata <= csr.tdata2; else NULL; end if; -- tdata2 (r/w): address-compare
|
-- when csr_tdata3_c => if (CPU_EXTENSION_RISCV_DEBUG) then csr.rdata <= (others => '0'); else NULL; end if; -- tdata3 (r/w): implemented but always zero
|
-- when csr_tdata3_c => if (CPU_EXTENSION_RISCV_DEBUG) then csr.rdata <= (others => '0'); else NULL; end if; -- tdata3 (r/w): implemented but always zero
|
when csr_tinfo_c => if (CPU_EXTENSION_RISCV_DEBUG) then csr.rdata <= x"00000004"; else NULL; end if; -- tinfo (r/w): address-match trigger only
|
when csr_tinfo_c => if (CPU_EXTENSION_RISCV_DEBUG) then csr.rdata <= x"00000004"; else NULL; end if; -- tinfo (r/w): address-match trigger only
|
-- when csr_tcontrol_c => if (CPU_EXTENSION_RISCV_DEBUG) then csr.rdata <= (others => '0'); else NULL; end if; -- tcontrol (r/w): implemented but always zero
|
-- when csr_tcontrol_c => if (CPU_EXTENSION_RISCV_DEBUG) then csr.rdata <= (others => '0'); else NULL; end if; -- tcontrol (r/w): implemented but always zero
|
-- when csr_mcontext_c => if (CPU_EXTENSION_RISCV_DEBUG) then csr.rdata <= (others => '0'); else NULL; end if; -- mcontext (r/w): implemented but always zero
|
-- when csr_mcontext_c => if (CPU_EXTENSION_RISCV_DEBUG) then csr.rdata <= (others => '0'); else NULL; end if; -- mcontext (r/w): implemented but always zero
|
-- when csr_scontext_c => if (CPU_EXTENSION_RISCV_DEBUG) then csr.rdata <= (others => '0'); else NULL; end if; -- scontext (r/w): implemented but always zero
|
-- when csr_scontext_c => if (CPU_EXTENSION_RISCV_DEBUG) then csr.rdata <= (others => '0'); else NULL; end if; -- scontext (r/w): implemented but always zero
|
|
|
-- NEORV32-specific (RISC-V "custom") read-only CSRs --
|
-- NEORV32-specific (RISC-V "custom") read-only CSRs --
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
-- machine extended ISA extensions information --
|
-- machine extended ISA extensions information --
|
when csr_mxisa_c =>
|
when csr_mxisa_c =>
|
-- ISA extended (sub-)extensions --
|
-- ISA extended (sub-)extensions --
|
csr.rdata(00) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zicsr); -- Zicsr: privileged architecture (!!!)
|
csr.rdata(00) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zicsr); -- Zicsr: privileged architecture (!!!)
|
csr.rdata(01) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zifencei); -- Zifencei: instruction stream sync.
|
csr.rdata(01) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zifencei); -- Zifencei: instruction stream sync.
|
csr.rdata(02) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zmmul); -- Zmmul: mul/div
|
csr.rdata(02) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zmmul); -- Zmmul: mul/div
|
csr.rdata(03) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zxcfu); -- Zxcfu: custom RISC-V instructions
|
csr.rdata(03) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zxcfu); -- Zxcfu: custom RISC-V instructions
|
csr.rdata(04) <= '0'; -- reserved
|
csr.rdata(04) <= '0'; -- reserved
|
csr.rdata(05) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zfinx); -- Zfinx: FPU using x registers, "F-alternative"
|
csr.rdata(05) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zfinx); -- Zfinx: FPU using x registers, "F-alternative"
|
csr.rdata(06) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zicntr) and
|
csr.rdata(06) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zicntr) and
|
bool_to_ulogic_f(boolean(CPU_CNT_WIDTH /= 64)); -- Zxscnt: reduced-size CPU counters (from Zicntr)
|
bool_to_ulogic_f(boolean(CPU_CNT_WIDTH /= 64)); -- Zxscnt: reduced-size CPU counters (from Zicntr)
|
csr.rdata(07) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zicntr); -- Zicntr: base instructions, cycle and time CSRs
|
csr.rdata(07) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zicntr); -- Zicntr: base instructions, cycle and time CSRs
|
csr.rdata(08) <= bool_to_ulogic_f(boolean(PMP_NUM_REGIONS > 0)); -- PMP: physical memory protection (Zspmp)
|
csr.rdata(08) <= bool_to_ulogic_f(boolean(PMP_NUM_REGIONS > 0)); -- PMP: physical memory protection (Zspmp)
|
csr.rdata(09) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zihpm); -- Zihpm: hardware performance monitors
|
csr.rdata(09) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_Zihpm); -- Zihpm: hardware performance monitors
|
csr.rdata(10) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_DEBUG); -- RISC-V debug mode
|
csr.rdata(10) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_DEBUG); -- RISC-V debug mode
|
-- tuning options --
|
-- tuning options --
|
csr.rdata(30) <= bool_to_ulogic_f(FAST_MUL_EN); -- DSP-based multiplication (M extensions only)
|
csr.rdata(30) <= bool_to_ulogic_f(FAST_MUL_EN); -- DSP-based multiplication (M extensions only)
|
csr.rdata(31) <= bool_to_ulogic_f(FAST_SHIFT_EN); -- parallel logic for shifts (barrel shifters)
|
csr.rdata(31) <= bool_to_ulogic_f(FAST_SHIFT_EN); -- parallel logic for shifts (barrel shifters)
|
|
|
-- undefined/unavailable --
|
-- undefined/unavailable --
|
-- --------------------------------------------------------------------
|
-- --------------------------------------------------------------------
|
when others =>
|
when others =>
|
NULL; -- not implemented, read as zero
|
NULL; -- not implemented, read as zero
|
|
|
end case;
|
end case;
|
end if;
|
end if;
|
end if;
|
end if;
|
end process csr_read_access;
|
end process csr_read_access;
|
|
|
-- CSR read data output --
|
-- CSR read data output --
|
csr_rdata_o <= csr.rdata;
|
csr_rdata_o <= csr.rdata;
|
|
|
|
|
-- ****************************************************************************************************************************
|
-- ****************************************************************************************************************************
|
-- CPU Counters / HPMs (CSRs)
|
-- CPU Counters / HPMs (CSRs)
|
-- ****************************************************************************************************************************
|
-- ****************************************************************************************************************************
|
|
|
-- Control and Status Registers - Counters ------------------------------------------------
|
-- Control and Status Registers - Counters ------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
csr_counters: process(rstn_i, clk_i)
|
csr_counters: process(rstn_i, clk_i)
|
begin
|
begin
|
-- Counter CSRs (each counter is split into two 32-bit counters - coupled via an MSB overflow FF)
|
|
if (rstn_i = '0') then
|
if (rstn_i = '0') then
|
csr.mcycle <= (others => def_rst_val_c);
|
csr.mcycle <= (others => def_rst_val_c);
|
csr.mcycle_ovfl <= (others => def_rst_val_c);
|
csr.mcycle_ovfl <= (others => def_rst_val_c);
|
csr.mcycleh <= (others => def_rst_val_c);
|
csr.mcycleh <= (others => def_rst_val_c);
|
csr.minstret <= (others => def_rst_val_c);
|
csr.minstret <= (others => def_rst_val_c);
|
csr.minstret_ovfl <= (others => def_rst_val_c);
|
csr.minstret_ovfl <= (others => def_rst_val_c);
|
csr.minstreth <= (others => def_rst_val_c);
|
csr.minstreth <= (others => def_rst_val_c);
|
csr.mhpmcounter <= (others => (others => def_rst_val_c));
|
csr.mhpmcounter <= (others => (others => def_rst_val_c));
|
csr.mhpmcounter_ovfl <= (others => (others => def_rst_val_c));
|
csr.mhpmcounter_ovfl <= (others => (others => def_rst_val_c));
|
csr.mhpmcounterh <= (others => (others => def_rst_val_c));
|
csr.mhpmcounterh <= (others => (others => def_rst_val_c));
|
elsif rising_edge(clk_i) then
|
elsif rising_edge(clk_i) then
|
|
|
-- [m]cycle --
|
-- [m]cycle --
|
if (cpu_cnt_lo_width_c > 0) and (CPU_EXTENSION_RISCV_Zicntr = true) then
|
if (cpu_cnt_lo_width_c > 0) and (CPU_EXTENSION_RISCV_Zicntr = true) then
|
csr.mcycle_ovfl(0) <= csr.mcycle_nxt(csr.mcycle_nxt'left) and (not csr.mcountinhibit_cy);
|
csr.mcycle_ovfl(0) <= csr.mcycle_nxt(csr.mcycle_nxt'left) and (not csr.mcountinhibit_cy);
|
if (csr.we = '1') and (csr.addr = csr_mcycle_c) then -- write access
|
if (csr.we = '1') and (csr.addr = csr_mcycle_c) then -- write access
|
csr.mcycle(cpu_cnt_lo_width_c-1 downto 0) <= csr.wdata(cpu_cnt_lo_width_c-1 downto 0);
|
csr.mcycle(cpu_cnt_lo_width_c-1 downto 0) <= csr.wdata(cpu_cnt_lo_width_c-1 downto 0);
|
elsif (csr.mcountinhibit_cy = '0') and (cnt_event(hpmcnt_event_cy_c) = '1') and (debug_ctrl.running = '0') then -- non-inhibited automatic update and not in debug mode
|
elsif (csr.mcountinhibit_cy = '0') and (cnt_event(hpmcnt_event_cy_c) = '1') and (debug_ctrl.running = '0') then -- non-inhibited automatic update and not in debug mode
|
csr.mcycle(cpu_cnt_lo_width_c-1 downto 0) <= csr.mcycle_nxt(cpu_cnt_lo_width_c-1 downto 0);
|
csr.mcycle(cpu_cnt_lo_width_c-1 downto 0) <= csr.mcycle_nxt(cpu_cnt_lo_width_c-1 downto 0);
|
end if;
|
end if;
|
else
|
else
|
csr.mcycle_ovfl <= (others => '-');
|
csr.mcycle_ovfl <= (others => '0');
|
csr.mcycle <= (others => '-');
|
csr.mcycle <= (others => '0');
|
end if;
|
end if;
|
|
|
-- [m]cycleh --
|
-- [m]cycleh --
|
if (cpu_cnt_hi_width_c > 0) and (CPU_EXTENSION_RISCV_Zicntr = true) then
|
if (cpu_cnt_hi_width_c > 0) and (CPU_EXTENSION_RISCV_Zicntr = true) then
|
if (csr.we = '1') and (csr.addr = csr_mcycleh_c) then -- write access
|
if (csr.we = '1') and (csr.addr = csr_mcycleh_c) then -- write access
|
csr.mcycleh(cpu_cnt_hi_width_c-1 downto 0) <= csr.wdata(cpu_cnt_hi_width_c-1 downto 0);
|
csr.mcycleh(cpu_cnt_hi_width_c-1 downto 0) <= csr.wdata(cpu_cnt_hi_width_c-1 downto 0);
|
else -- automatic update
|
else -- automatic update
|
csr.mcycleh(cpu_cnt_hi_width_c-1 downto 0) <= std_ulogic_vector(unsigned(csr.mcycleh(cpu_cnt_hi_width_c-1 downto 0)) + unsigned(csr.mcycle_ovfl));
|
csr.mcycleh(cpu_cnt_hi_width_c-1 downto 0) <= std_ulogic_vector(unsigned(csr.mcycleh(cpu_cnt_hi_width_c-1 downto 0)) + unsigned(csr.mcycle_ovfl));
|
end if;
|
end if;
|
else
|
else
|
csr.mcycleh <= (others => '-');
|
csr.mcycleh <= (others => '0');
|
end if;
|
end if;
|
|
|
|
|
-- [m]instret --
|
-- [m]instret --
|
if (cpu_cnt_lo_width_c > 0) and (CPU_EXTENSION_RISCV_Zicntr = true) then
|
if (cpu_cnt_lo_width_c > 0) and (CPU_EXTENSION_RISCV_Zicntr = true) then
|
csr.minstret_ovfl(0) <= csr.minstret_nxt(csr.minstret_nxt'left) and (not csr.mcountinhibit_ir);
|
csr.minstret_ovfl(0) <= csr.minstret_nxt(csr.minstret_nxt'left) and (not csr.mcountinhibit_ir);
|
if (csr.we = '1') and (csr.addr = csr_minstret_c) then -- write access
|
if (csr.we = '1') and (csr.addr = csr_minstret_c) then -- write access
|
csr.minstret(cpu_cnt_lo_width_c-1 downto 0) <= csr.wdata(cpu_cnt_lo_width_c-1 downto 0);
|
csr.minstret(cpu_cnt_lo_width_c-1 downto 0) <= csr.wdata(cpu_cnt_lo_width_c-1 downto 0);
|
elsif (csr.mcountinhibit_ir = '0') and (cnt_event(hpmcnt_event_ir_c) = '1') and (debug_ctrl.running = '0') then -- non-inhibited automatic update and not in debug mode
|
elsif (csr.mcountinhibit_ir = '0') and (cnt_event(hpmcnt_event_ir_c) = '1') and (debug_ctrl.running = '0') then -- non-inhibited automatic update and not in debug mode
|
csr.minstret(cpu_cnt_lo_width_c-1 downto 0) <= csr.minstret_nxt(cpu_cnt_lo_width_c-1 downto 0);
|
csr.minstret(cpu_cnt_lo_width_c-1 downto 0) <= csr.minstret_nxt(cpu_cnt_lo_width_c-1 downto 0);
|
end if;
|
end if;
|
else
|
else
|
csr.minstret_ovfl <= (others => '-');
|
csr.minstret_ovfl <= (others => '0');
|
csr.minstret <= (others => '-');
|
csr.minstret <= (others => '0');
|
end if;
|
end if;
|
|
|
-- [m]instreth --
|
-- [m]instreth --
|
if (cpu_cnt_hi_width_c > 0) and (CPU_EXTENSION_RISCV_Zicntr = true) then
|
if (cpu_cnt_hi_width_c > 0) and (CPU_EXTENSION_RISCV_Zicntr = true) then
|
if (csr.we = '1') and (csr.addr = csr_minstreth_c) then -- write access
|
if (csr.we = '1') and (csr.addr = csr_minstreth_c) then -- write access
|
csr.minstreth(cpu_cnt_hi_width_c-1 downto 0) <= csr.wdata(cpu_cnt_hi_width_c-1 downto 0);
|
csr.minstreth(cpu_cnt_hi_width_c-1 downto 0) <= csr.wdata(cpu_cnt_hi_width_c-1 downto 0);
|
else -- automatic update
|
else -- automatic update
|
csr.minstreth(cpu_cnt_hi_width_c-1 downto 0) <= std_ulogic_vector(unsigned(csr.minstreth(cpu_cnt_hi_width_c-1 downto 0)) + unsigned(csr.minstret_ovfl));
|
csr.minstreth(cpu_cnt_hi_width_c-1 downto 0) <= std_ulogic_vector(unsigned(csr.minstreth(cpu_cnt_hi_width_c-1 downto 0)) + unsigned(csr.minstret_ovfl));
|
end if;
|
end if;
|
else
|
else
|
csr.minstreth <= (others => '-');
|
csr.minstreth <= (others => '0');
|
end if;
|
end if;
|
|
|
|
|
-- [machine] hardware performance monitors (counters) --
|
-- [machine] hardware performance monitors (counters) --
|
for i in 0 to HPM_NUM_CNTS-1 loop
|
for i in 0 to HPM_NUM_CNTS-1 loop
|
|
|
-- [m]hpmcounter* --
|
-- [m]hpmcounter* --
|
if (hpm_cnt_lo_width_c > 0) and (CPU_EXTENSION_RISCV_Zihpm = true) then
|
if (hpm_cnt_lo_width_c > 0) and (CPU_EXTENSION_RISCV_Zihpm = true) then
|
csr.mhpmcounter_ovfl(i)(0) <= csr.mhpmcounter_nxt(i)(csr.mhpmcounter_nxt(i)'left) and (not csr.mcountinhibit_hpm(i));
|
csr.mhpmcounter_ovfl(i)(0) <= csr.mhpmcounter_nxt(i)(csr.mhpmcounter_nxt(i)'left) and (not csr.mcountinhibit_hpm(i));
|
if (csr.we = '1') and (csr.addr = std_ulogic_vector(unsigned(csr_mhpmcounter3_c) + i)) then -- write access
|
if (csr.we = '1') and (csr.addr = std_ulogic_vector(unsigned(csr_mhpmcounter3_c) + i)) then -- write access
|
csr.mhpmcounter(i)(hpm_cnt_lo_width_c-1 downto 0) <= csr.wdata(hpm_cnt_lo_width_c-1 downto 0);
|
csr.mhpmcounter(i)(hpm_cnt_lo_width_c-1 downto 0) <= csr.wdata(hpm_cnt_lo_width_c-1 downto 0);
|
elsif (csr.mcountinhibit_hpm(i) = '0') and (hpmcnt_trigger(i) = '1') then -- non-inhibited automatic update
|
elsif (csr.mcountinhibit_hpm(i) = '0') and (hpmcnt_trigger(i) = '1') then -- non-inhibited automatic update
|
csr.mhpmcounter(i)(hpm_cnt_lo_width_c-1 downto 0) <= csr.mhpmcounter_nxt(i)(hpm_cnt_lo_width_c-1 downto 0);
|
csr.mhpmcounter(i)(hpm_cnt_lo_width_c-1 downto 0) <= csr.mhpmcounter_nxt(i)(hpm_cnt_lo_width_c-1 downto 0);
|
end if;
|
end if;
|
else
|
else
|
csr.mhpmcounter_ovfl(i) <= (others => '-');
|
csr.mhpmcounter_ovfl(i) <= (others => '0');
|
csr.mhpmcounter(i) <= (others => '-');
|
csr.mhpmcounter(i) <= (others => '0');
|
end if;
|
end if;
|
|
|
-- [m]hpmcounter*h --
|
-- [m]hpmcounter*h --
|
if (hpm_cnt_hi_width_c > 0) and (CPU_EXTENSION_RISCV_Zihpm = true) then
|
if (hpm_cnt_hi_width_c > 0) and (CPU_EXTENSION_RISCV_Zihpm = true) then
|
if (csr.we = '1') and (csr.addr = std_ulogic_vector(unsigned(csr_mhpmcounter3h_c) + i)) then -- write access
|
if (csr.we = '1') and (csr.addr = std_ulogic_vector(unsigned(csr_mhpmcounter3h_c) + i)) then -- write access
|
csr.mhpmcounterh(i)(hpm_cnt_hi_width_c-1 downto 0) <= csr.wdata(hpm_cnt_hi_width_c-1 downto 0);
|
csr.mhpmcounterh(i)(hpm_cnt_hi_width_c-1 downto 0) <= csr.wdata(hpm_cnt_hi_width_c-1 downto 0);
|
else -- automatic update
|
else -- automatic update
|
csr.mhpmcounterh(i)(hpm_cnt_hi_width_c-1 downto 0) <= std_ulogic_vector(unsigned(csr.mhpmcounterh(i)(hpm_cnt_hi_width_c-1 downto 0)) + unsigned(csr.mhpmcounter_ovfl(i)));
|
csr.mhpmcounterh(i)(hpm_cnt_hi_width_c-1 downto 0) <= std_ulogic_vector(unsigned(csr.mhpmcounterh(i)(hpm_cnt_hi_width_c-1 downto 0)) + unsigned(csr.mhpmcounter_ovfl(i)));
|
end if;
|
end if;
|
else
|
else
|
csr.mhpmcounterh(i) <= (others => '-');
|
csr.mhpmcounterh(i) <= (others => '0');
|
end if;
|
end if;
|
|
|
end loop; -- i
|
end loop; -- i
|
|
|
end if;
|
end if;
|
end process csr_counters;
|
end process csr_counters;
|
|
|
-- mcycle & minstret increment LOW --
|
-- mcycle & minstret increment LOW --
|
csr.mcycle_nxt <= std_ulogic_vector(unsigned('0' & csr.mcycle) + 1);
|
csr.mcycle_nxt <= std_ulogic_vector(unsigned('0' & csr.mcycle) + 1);
|
csr.minstret_nxt <= std_ulogic_vector(unsigned('0' & csr.minstret) + 1);
|
csr.minstret_nxt <= std_ulogic_vector(unsigned('0' & csr.minstret) + 1);
|
|
|
-- hpm counter increment LOW --
|
-- hpm counter increment LOW --
|
hmp_cnt_lo_inc:
|
hmp_cnt_lo_inc:
|
for i in 0 to HPM_NUM_CNTS-1 generate
|
for i in 0 to HPM_NUM_CNTS-1 generate
|
csr.mhpmcounter_nxt(i) <= std_ulogic_vector(unsigned('0' & csr.mhpmcounter(i)) + 1);
|
csr.mhpmcounter_nxt(i) <= std_ulogic_vector(unsigned('0' & csr.mhpmcounter(i)) + 1);
|
end generate;
|
end generate;
|
|
|
|
|
-- hpm counter read --
|
-- hpm counter read --
|
hpm_rd_dummy: process(csr)
|
hpm_rd_dummy: process(csr)
|
begin
|
begin
|
csr.mhpmevent_rd <= (others => (others => '0'));
|
csr.mhpmevent_rd <= (others => (others => '0'));
|
csr.mhpmcounter_rd <= (others => (others => '0'));
|
csr.mhpmcounter_rd <= (others => (others => '0'));
|
csr.mhpmcounterh_rd <= (others => (others => '0'));
|
csr.mhpmcounterh_rd <= (others => (others => '0'));
|
if (HPM_NUM_CNTS /= 0) and (CPU_EXTENSION_RISCV_Zihpm = true) then
|
if (HPM_NUM_CNTS /= 0) and (CPU_EXTENSION_RISCV_Zihpm = true) then
|
for i in 0 to HPM_NUM_CNTS-1 loop
|
for i in 0 to HPM_NUM_CNTS-1 loop
|
csr.mhpmevent_rd(i)(hpmcnt_event_size_c-1 downto 0) <= csr.mhpmevent(i);
|
csr.mhpmevent_rd(i)(hpmcnt_event_size_c-1 downto 0) <= csr.mhpmevent(i);
|
if (hpm_cnt_lo_width_c > 0) then
|
if (hpm_cnt_lo_width_c > 0) then
|
csr.mhpmcounter_rd(i)(hpm_cnt_lo_width_c-1 downto 0) <= csr.mhpmcounter(i)(hpm_cnt_lo_width_c-1 downto 0);
|
csr.mhpmcounter_rd(i)(hpm_cnt_lo_width_c-1 downto 0) <= csr.mhpmcounter(i)(hpm_cnt_lo_width_c-1 downto 0);
|
end if;
|
end if;
|
if (hpm_cnt_hi_width_c > 0) then
|
if (hpm_cnt_hi_width_c > 0) then
|
csr.mhpmcounterh_rd(i)(hpm_cnt_hi_width_c-1 downto 0) <= csr.mhpmcounterh(i)(hpm_cnt_hi_width_c-1 downto 0);
|
csr.mhpmcounterh_rd(i)(hpm_cnt_hi_width_c-1 downto 0) <= csr.mhpmcounterh(i)(hpm_cnt_hi_width_c-1 downto 0);
|
end if;
|
end if;
|
end loop; -- i
|
end loop; -- i
|
end if;
|
end if;
|
end process hpm_rd_dummy;
|
end process hpm_rd_dummy;
|
|
|
|
|
-- Hardware Performance Monitor - Counter Event Control -----------------------------------
|
-- Hardware Performance Monitor - Counter Event Control (Triggers) ------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
hpmcnt_ctrl: process(clk_i)
|
hpmcnt_ctrl: process(clk_i)
|
begin
|
begin
|
if rising_edge(clk_i) then
|
if rising_edge(clk_i) then
|
-- enable selected triggers by ANDing actual events and according CSR configuration bits --
|
-- enable selected triggers by ANDing actual events and according CSR configuration bits --
|
-- OR everything to see if counter should increment --
|
-- OR everything to see if counter should increment --
|
hpmcnt_trigger <= (others => '0'); -- default
|
hpmcnt_trigger <= (others => '0'); -- default
|
if (HPM_NUM_CNTS /= 0) then
|
if (HPM_NUM_CNTS /= 0) then
|
for i in 0 to HPM_NUM_CNTS-1 loop
|
for i in 0 to HPM_NUM_CNTS-1 loop
|
-- do not increment if CPU is in debug mode --
|
-- do not increment if CPU is in debug mode --
|
hpmcnt_trigger(i) <= or_reduce_f(cnt_event and csr.mhpmevent(i)(cnt_event'left downto 0)) and (not debug_ctrl.running);
|
if (or_reduce_f(cnt_event and csr.mhpmevent(i)(cnt_event'left downto 0)) = '1') and (debug_ctrl.running = '0') then
|
|
hpmcnt_trigger(i) <= '1';
|
|
else
|
|
hpmcnt_trigger(i) <= '0';
|
|
end if;
|
end loop; -- i
|
end loop; -- i
|
end if;
|
end if;
|
end if;
|
end if;
|
end process hpmcnt_ctrl;
|
end process hpmcnt_ctrl;
|
|
|
|
hpm_triggers:
|
|
if (HPM_NUM_CNTS /= 0) generate
|
-- counter event trigger - RISC-V-specific --
|
-- counter event trigger - RISC-V-specific --
|
cnt_event(hpmcnt_event_cy_c) <= not execute_engine.sleep; -- active cycle
|
cnt_event(hpmcnt_event_cy_c) <= not execute_engine.sleep; -- active cycle
|
cnt_event(hpmcnt_event_never_c) <= '0'; -- "never"
|
cnt_event(hpmcnt_event_never_c) <= '0'; -- "never"
|
cnt_event(hpmcnt_event_ir_c) <= '1' when (execute_engine.state = EXECUTE) else '0'; -- (any) retired instruction
|
cnt_event(hpmcnt_event_ir_c) <= '1' when (execute_engine.state = EXECUTE) else '0'; -- (any) retired instruction
|
|
|
-- counter event trigger - custom / NEORV32-specific --
|
-- counter event trigger - custom / NEORV32-specific --
|
cnt_event(hpmcnt_event_cir_c) <= '1' when (execute_engine.state = EXECUTE) and (execute_engine.is_ci = '1') else '0'; -- retired compressed instruction
|
cnt_event(hpmcnt_event_cir_c) <= '1' when (execute_engine.state = EXECUTE) and (execute_engine.is_ci = '1') else '0'; -- retired compressed instruction
|
cnt_event(hpmcnt_event_wait_if_c) <= '1' when (fetch_engine.state = IFETCH_ISSUE) and (fetch_engine.state_prev = IFETCH_ISSUE) else '0'; -- instruction fetch memory wait cycle
|
cnt_event(hpmcnt_event_wait_if_c) <= '1' when (fetch_engine.state = IFETCH_ISSUE) and (fetch_engine.state_prev = IFETCH_ISSUE) else '0'; -- instruction fetch memory wait cycle
|
cnt_event(hpmcnt_event_wait_ii_c) <= '1' when (execute_engine.state = DISPATCH) and (execute_engine.state_prev = DISPATCH) else '0'; -- instruction issue wait cycle
|
cnt_event(hpmcnt_event_wait_ii_c) <= '1' when (execute_engine.state = DISPATCH) and (execute_engine.state_prev = DISPATCH) else '0'; -- instruction issue wait cycle
|
cnt_event(hpmcnt_event_wait_mc_c) <= '1' when (execute_engine.state = ALU_WAIT) else '0'; -- multi-cycle alu-operation wait cycle
|
cnt_event(hpmcnt_event_wait_mc_c) <= '1' when (execute_engine.state = ALU_WAIT) else '0'; -- multi-cycle alu-operation wait cycle
|
|
|
cnt_event(hpmcnt_event_load_c) <= '1' when (ctrl(ctrl_bus_rd_c) = '1') else '0'; -- load operation
|
cnt_event(hpmcnt_event_load_c) <= '1' when (ctrl(ctrl_bus_rd_c) = '1') else '0'; -- load operation
|
cnt_event(hpmcnt_event_store_c) <= '1' when (ctrl(ctrl_bus_wr_c) = '1') else '0'; -- store operation
|
cnt_event(hpmcnt_event_store_c) <= '1' when (ctrl(ctrl_bus_wr_c) = '1') else '0'; -- store operation
|
cnt_event(hpmcnt_event_wait_ls_c) <= '1' when (execute_engine.state = LOADSTORE_2) and (execute_engine.state_prev = LOADSTORE_2) else '0'; -- load/store memory wait cycle
|
cnt_event(hpmcnt_event_wait_ls_c) <= '1' when (execute_engine.state = LOADSTORE_2) and (execute_engine.state_prev = LOADSTORE_2) else '0'; -- load/store memory wait cycle
|
|
|
cnt_event(hpmcnt_event_jump_c) <= '1' when (execute_engine.state = BRANCH) and (execute_engine.i_reg(instr_opcode_lsb_c+2) = '1') else '0'; -- jump (unconditional)
|
cnt_event(hpmcnt_event_jump_c) <= '1' when (execute_engine.state = BRANCH) and (execute_engine.i_reg(instr_opcode_lsb_c+2) = '1') else '0'; -- jump (unconditional)
|
cnt_event(hpmcnt_event_branch_c) <= '1' when (execute_engine.state = BRANCH) and (execute_engine.i_reg(instr_opcode_lsb_c+2) = '0') else '0'; -- branch (conditional, taken or not taken)
|
cnt_event(hpmcnt_event_branch_c) <= '1' when (execute_engine.state = BRANCH) and (execute_engine.i_reg(instr_opcode_lsb_c+2) = '0') else '0'; -- branch (conditional, taken or not taken)
|
cnt_event(hpmcnt_event_tbranch_c) <= '1' when (execute_engine.state = BRANCH) and (execute_engine.i_reg(instr_opcode_lsb_c+2) = '0') and (execute_engine.branch_taken = '1') else '0'; -- taken branch (conditional)
|
cnt_event(hpmcnt_event_tbranch_c) <= '1' when (execute_engine.state = BRANCH) and (execute_engine.i_reg(instr_opcode_lsb_c+2) = '0') and (execute_engine.branch_taken = '1') else '0'; -- taken branch (conditional)
|
|
|
cnt_event(hpmcnt_event_trap_c) <= '1' when (trap_ctrl.env_start_ack = '1') else '0'; -- entered trap
|
cnt_event(hpmcnt_event_trap_c) <= '1' when (trap_ctrl.env_start_ack = '1') else '0'; -- entered trap
|
cnt_event(hpmcnt_event_illegal_c) <= '1' when (trap_ctrl.env_start_ack = '1') and (trap_ctrl.cause = trap_iil_c) else '0'; -- illegal operation
|
cnt_event(hpmcnt_event_illegal_c) <= '1' when (trap_ctrl.env_start_ack = '1') and (trap_ctrl.cause = trap_iil_c) else '0'; -- illegal operation
|
|
end generate;
|
|
|
|
|
-- ****************************************************************************************************************************
|
-- ****************************************************************************************************************************
|
-- CPU Debug Mode (Part of the On-Chip Debugger)
|
-- CPU Debug Mode (Part of the On-Chip Debugger)
|
-- ****************************************************************************************************************************
|
-- ****************************************************************************************************************************
|
|
|
-- Debug Control --------------------------------------------------------------------------
|
-- Debug Control --------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
|
ocd_en:
|
|
if (CPU_EXTENSION_RISCV_DEBUG = true) generate
|
debug_control: process(rstn_i, clk_i)
|
debug_control: process(rstn_i, clk_i)
|
begin
|
begin
|
if (rstn_i = '0') then
|
if (rstn_i = '0') then
|
debug_ctrl.state <= DEBUG_OFFLINE;
|
debug_ctrl.state <= DEBUG_OFFLINE;
|
debug_ctrl.ext_halt_req <= '0';
|
debug_ctrl.ext_halt_req <= '0';
|
elsif rising_edge(clk_i) then
|
elsif rising_edge(clk_i) then
|
if (CPU_EXTENSION_RISCV_DEBUG = true) then
|
|
|
|
-- external halt request (from Debug Module) --
|
-- external halt request (from Debug Module) --
|
debug_ctrl.ext_halt_req <= db_halt_req_i;
|
debug_ctrl.ext_halt_req <= db_halt_req_i;
|
|
|
-- state machine --
|
-- state machine --
|
case debug_ctrl.state is
|
case debug_ctrl.state is
|
|
|
when DEBUG_OFFLINE => -- not in debug mode, waiting for entering request
|
when DEBUG_OFFLINE => -- not in debug mode, waiting for entering request
|
if (debug_ctrl.trig_halt = '1') or -- external request (from DM)
|
if (debug_ctrl.trig_halt = '1') or -- external request (from DM)
|
(debug_ctrl.trig_break = '1') or -- ebreak instruction
|
(debug_ctrl.trig_break = '1') or -- ebreak instruction
|
(debug_ctrl.trig_hw = '1') or -- hardware trigger module
|
(debug_ctrl.trig_hw = '1') or -- hardware trigger module
|
(debug_ctrl.trig_step = '1') then -- single-stepping mode
|
(debug_ctrl.trig_step = '1') then -- single-stepping mode
|
debug_ctrl.state <= DEBUG_PENDING;
|
debug_ctrl.state <= DEBUG_PENDING;
|
end if;
|
end if;
|
|
|
when DEBUG_PENDING => -- waiting to start debug mode
|
when DEBUG_PENDING => -- waiting to start debug mode
|
if (trap_ctrl.env_start_ack = '1') and (trap_ctrl.cause(5) = '1') then -- processing trap entry into debug mode
|
if (trap_ctrl.env_start_ack = '1') and (trap_ctrl.cause(5) = '1') then -- processing trap entry into debug mode
|
debug_ctrl.state <= DEBUG_ONLINE;
|
debug_ctrl.state <= DEBUG_ONLINE;
|
end if;
|
end if;
|
|
|
when DEBUG_ONLINE => -- we are in debug mode
|
when DEBUG_ONLINE => -- we are in debug mode
|
if (debug_ctrl.dret = '1') then -- DRET instruction
|
if (debug_ctrl.dret = '1') then -- DRET instruction
|
debug_ctrl.state <= DEBUG_EXIT;
|
debug_ctrl.state <= DEBUG_EXIT;
|
end if;
|
end if;
|
|
|
when DEBUG_EXIT => -- leaving debug mode
|
when DEBUG_EXIT => -- leaving debug mode
|
if (execute_engine.state = TRAP_EXECUTE) then -- processing trap exit
|
if (execute_engine.state = TRAP_EXECUTE) then -- processing trap exit
|
debug_ctrl.state <= DEBUG_OFFLINE;
|
debug_ctrl.state <= DEBUG_OFFLINE;
|
end if;
|
end if;
|
|
|
when others => -- undefined
|
when others => -- undefined
|
debug_ctrl.state <= DEBUG_OFFLINE;
|
debug_ctrl.state <= DEBUG_OFFLINE;
|
|
|
end case;
|
end case;
|
else -- debug mode NOT implemented
|
|
debug_ctrl.state <= DEBUG_OFFLINE;
|
|
debug_ctrl.ext_halt_req <= '0';
|
|
end if;
|
|
end if;
|
end if;
|
end process debug_control;
|
end process debug_control;
|
|
end generate;
|
|
|
-- state decoding --
|
-- state decoding --
|
debug_ctrl.pending <= '1' when (debug_ctrl.state = DEBUG_PENDING) and (CPU_EXTENSION_RISCV_DEBUG = true) else '0';
|
debug_ctrl.pending <= '1' when (debug_ctrl.state = DEBUG_PENDING) and (CPU_EXTENSION_RISCV_DEBUG = true) else '0';
|
debug_ctrl.running <= '1' when ((debug_ctrl.state = DEBUG_ONLINE) or (debug_ctrl.state = DEBUG_EXIT)) and (CPU_EXTENSION_RISCV_DEBUG = true) else '0';
|
debug_ctrl.running <= '1' when ((debug_ctrl.state = DEBUG_ONLINE) or (debug_ctrl.state = DEBUG_EXIT)) and (CPU_EXTENSION_RISCV_DEBUG = true) else '0';
|
|
|
-- entry debug mode triggers --
|
-- entry debug mode triggers --
|
debug_ctrl.trig_hw <= hw_trigger_fire and (not debug_ctrl.running); -- enter debug mode by HW trigger module request
|
debug_ctrl.trig_hw <= hw_trigger_fire and (not debug_ctrl.running); -- enter debug mode by HW trigger module request
|
debug_ctrl.trig_break <= trap_ctrl.break_point and (debug_ctrl.running or -- re-enter debug mode
|
debug_ctrl.trig_break <= trap_ctrl.break_point and (debug_ctrl.running or -- re-enter debug mode
|
(( csr.privilege) and csr.dcsr_ebreakm) or -- enabled goto-debug-mode in machine mode on "ebreak"
|
(( csr.privilege) and csr.dcsr_ebreakm) or -- enabled goto-debug-mode in machine mode on "ebreak"
|
((not csr.privilege) and csr.dcsr_ebreaku)); -- enabled goto-debug-mode in user mode on "ebreak"
|
((not csr.privilege) and csr.dcsr_ebreaku)); -- enabled goto-debug-mode in user mode on "ebreak"
|
debug_ctrl.trig_halt <= debug_ctrl.ext_halt_req and (not debug_ctrl.running); -- external halt request (if not halted already)
|
debug_ctrl.trig_halt <= debug_ctrl.ext_halt_req and (not debug_ctrl.running); -- external halt request (if not halted already)
|
debug_ctrl.trig_step <= csr.dcsr_step and (not debug_ctrl.running); -- single-step mode (trigger when NOT CURRENTLY in debug mode)
|
debug_ctrl.trig_step <= csr.dcsr_step and (not debug_ctrl.running); -- single-step mode (trigger when NOT CURRENTLY in debug mode)
|
|
|
|
|
-- Debug Control and Status Register (dcsr) - Read-Back -----------------------------------
|
-- Debug Control and Status Register (dcsr) - Read-Back -----------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
csr.dcsr_rd(31 downto 28) <= "0100"; -- xdebugver: external debug support compatible to spec
|
csr.dcsr_rd(31 downto 28) <= "0100"; -- xdebugver: external debug support compatible to spec
|
csr.dcsr_rd(27 downto 16) <= (others => '0'); -- reserved
|
csr.dcsr_rd(27 downto 16) <= (others => '0'); -- reserved
|
csr.dcsr_rd(15) <= csr.dcsr_ebreakm; -- ebreakm: what happens on ebreak in m-mode? (normal trap OR debug-enter)
|
csr.dcsr_rd(15) <= csr.dcsr_ebreakm; -- ebreakm: what happens on ebreak in m-mode? (normal trap OR debug-enter)
|
csr.dcsr_rd(14) <= '0'; -- ebreakh: hypervisor mode not implemented
|
csr.dcsr_rd(14) <= '0'; -- ebreakh: hypervisor mode not implemented
|
csr.dcsr_rd(13) <= '0'; -- ebreaks: supervisor mode not implemented
|
csr.dcsr_rd(13) <= '0'; -- ebreaks: supervisor mode not implemented
|
csr.dcsr_rd(12) <= csr.dcsr_ebreaku when (CPU_EXTENSION_RISCV_U = true) else '0'; -- ebreaku: what happens on ebreak in u-mode? (normal trap OR debug-enter)
|
csr.dcsr_rd(12) <= csr.dcsr_ebreaku when (CPU_EXTENSION_RISCV_U = true) else '0'; -- ebreaku: what happens on ebreak in u-mode? (normal trap OR debug-enter)
|
csr.dcsr_rd(11) <= '0'; -- stepie: interrupts are disabled during single-stepping
|
csr.dcsr_rd(11) <= '0'; -- stepie: interrupts are disabled during single-stepping
|
csr.dcsr_rd(10) <= '1'; -- stopcount: standard counters and HPMs are stopped when in debug mode
|
csr.dcsr_rd(10) <= '1'; -- stopcount: standard counters and HPMs are stopped when in debug mode
|
csr.dcsr_rd(09) <= '0'; -- stoptime: timers increment as usual
|
csr.dcsr_rd(09) <= '0'; -- stoptime: timers increment as usual
|
csr.dcsr_rd(08 downto 06) <= csr.dcsr_cause; -- debug mode entry cause
|
csr.dcsr_rd(08 downto 06) <= csr.dcsr_cause; -- debug mode entry cause
|
csr.dcsr_rd(05) <= '0'; -- reserved
|
csr.dcsr_rd(05) <= '0'; -- reserved
|
csr.dcsr_rd(04) <= '0'; -- mprven: mstatus.mprv is ignored in debug mode
|
csr.dcsr_rd(04) <= '0'; -- mprven: mstatus.mprv is ignored in debug mode
|
csr.dcsr_rd(03) <= '0'; -- nmip: no pending non-maskable interrupt
|
csr.dcsr_rd(03) <= '0'; -- nmip: no pending non-maskable interrupt
|
csr.dcsr_rd(02) <= csr.dcsr_step; -- step: single-step mode
|
csr.dcsr_rd(02) <= csr.dcsr_step; -- step: single-step mode
|
csr.dcsr_rd(01 downto 00) <= (others => csr.dcsr_prv); -- prv: privilege mode when debug mode was entered
|
csr.dcsr_rd(01 downto 00) <= (others => csr.dcsr_prv); -- prv: privilege mode when debug mode was entered
|
|
|
|
|
-- ****************************************************************************************************************************
|
-- ****************************************************************************************************************************
|
-- Hardware Trigger Module (Part of the On-Chip Debugger)
|
-- Hardware Trigger Module (Part of the On-Chip Debugger)
|
-- ****************************************************************************************************************************
|
-- ****************************************************************************************************************************
|
|
|
-- trigger to enter debug-mode: instruction address match (fire AFTER execution) --
|
-- trigger to enter debug-mode: instruction address match (fire AFTER execution) --
|
hw_trigger_fire <= '1' when (CPU_EXTENSION_RISCV_DEBUG = true) and (csr.tdata1_exe = '1') and
|
hw_trigger_fire <= '1' when (CPU_EXTENSION_RISCV_DEBUG = true) and (csr.tdata1_exe = '1') and
|
(csr.tdata2(data_width_c-1 downto 1) = execute_engine.pc(data_width_c-1 downto 1)) else '0';
|
(csr.tdata2(data_width_c-1 downto 1) = execute_engine.pc(data_width_c-1 downto 1)) and
|
|
(execute_engine.state = EXECUTE) else '0';
|
|
|
|
|
-- Match Control CSR (mcontrol @ tdata1) - Read-Back --------------------------------------
|
-- Match Control CSR (mcontrol @ tdata1) - Read-Back --------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
-- -------------------------------------------------------------------------------------------
|
csr.tdata1_rd(31 downto 28) <= "0010"; -- type: address(/data) match trigger
|
csr.tdata1_rd(31 downto 28) <= "0010"; -- type: address(/data) match trigger
|
csr.tdata1_rd(27) <= '1'; -- dmode: only debug-mode can write tdata* registers
|
csr.tdata1_rd(27) <= '1'; -- dmode: only debug-mode can write tdata* registers
|
csr.tdata1_rd(26 downto 21) <= "000000"; -- maskmax: only exact values
|
csr.tdata1_rd(26 downto 21) <= "000000"; -- maskmax: only exact values
|
csr.tdata1_rd(20) <= '0'; -- hit: feature not implemented
|
csr.tdata1_rd(20) <= '0'; -- hit: feature not implemented
|
csr.tdata1_rd(19) <= '0'; -- select: fire on address match
|
csr.tdata1_rd(19) <= '0'; -- select: fire on address match
|
csr.tdata1_rd(18) <= '1'; -- timing: trigger **after** executing the triggering instruction
|
csr.tdata1_rd(18) <= '1'; -- timing: trigger **after** executing the triggering instruction
|
csr.tdata1_rd(17 downto 16) <= "00"; -- sizelo: match against an access of any size
|
csr.tdata1_rd(17 downto 16) <= "00"; -- sizelo: match against an access of any size
|
csr.tdata1_rd(15 downto 12) <= "0001"; -- action: enter debug mode on trigger
|
csr.tdata1_rd(15 downto 12) <= "0001"; -- action: enter debug mode on trigger
|
csr.tdata1_rd(11) <= '0'; -- chain: chaining not supported - there is only one trigger
|
csr.tdata1_rd(11) <= '0'; -- chain: chaining not supported - there is only one trigger
|
csr.tdata1_rd(10 downto 07) <= "0000"; -- match: only full-address-match
|
csr.tdata1_rd(10 downto 07) <= "0000"; -- match: only full-address-match
|
csr.tdata1_rd(6) <= '1'; -- m: trigger enabled when in machine mode
|
csr.tdata1_rd(6) <= '1'; -- m: trigger enabled when in machine mode
|
csr.tdata1_rd(5) <= '0'; -- h: hypervisor mode not supported
|
csr.tdata1_rd(5) <= '0'; -- h: hypervisor mode not supported
|
csr.tdata1_rd(4) <= '0'; -- s: supervisor mode not supported
|
csr.tdata1_rd(4) <= '0'; -- s: supervisor mode not supported
|
csr.tdata1_rd(3) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_U); -- u: trigger enabled when in user mode
|
csr.tdata1_rd(3) <= bool_to_ulogic_f(CPU_EXTENSION_RISCV_U); -- u: trigger enabled when in user mode
|
csr.tdata1_rd(2) <= csr.tdata1_exe; -- execute: enable trigger
|
csr.tdata1_rd(2) <= csr.tdata1_exe; -- execute: enable trigger
|
csr.tdata1_rd(1) <= '0'; -- store: store address or data matching not supported
|
csr.tdata1_rd(1) <= '0'; -- store: store address or data matching not supported
|
csr.tdata1_rd(0) <= '0'; -- load: load address or data matching not supported
|
csr.tdata1_rd(0) <= '0'; -- load: load address or data matching not supported
|
|
|
|
|
end neorv32_cpu_control_rtl;
|
end neorv32_cpu_control_rtl;
|
|
|