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----------------------------------------------------------------------------------------------
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--
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-- Input file : core_Pkg.vhd
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-- Design name : core_Pkg
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-- Author : Tamar Kranenburg
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-- Company : Delft University of Technology
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-- : Faculty EEMCS, Department ME&CE
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-- : Systems and Circuits group
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--
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-- Description : Package with components and type definitions for the interface
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-- of the components
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--
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--
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----------------------------------------------------------------------------------------------
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takar |
library ieee;
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use ieee.std_logic_1164.all;
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use ieee.std_logic_unsigned.all;
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takar |
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library mblite;
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use mblite.config_Pkg.all;
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use mblite.std_Pkg.all;
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takar |
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package core_Pkg is
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constant C_8_ZEROS : std_logic_vector ( 7 downto 0) := (others => '0');
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constant C_16_ZEROS : std_logic_vector (15 downto 0) := (others => '0');
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constant C_24_ZEROS : std_logic_vector (23 downto 0) := (others => '0');
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constant C_32_ZEROS : std_logic_vector (31 downto 0) := (others => '0');
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takar |
----------------------------------------------------------------------------------------------
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-- TYPES USED IN MB-LITE
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----------------------------------------------------------------------------------------------
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takar |
type alu_operation is (ALU_ADD, ALU_OR, ALU_AND, ALU_XOR, ALU_SHIFT, ALU_SEXT8, ALU_SEXT16, ALU_MUL, ALU_BS);
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type src_type_a is (ALU_SRC_REGA, ALU_SRC_NOT_REGA, ALU_SRC_PC, ALU_SRC_ZERO);
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type src_type_b is (ALU_SRC_REGB, ALU_SRC_NOT_REGB, ALU_SRC_IMM, ALU_SRC_NOT_IMM);
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type carry_type is (CARRY_ZERO, CARRY_ONE, CARRY_ALU, CARRY_ARITH);
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type carry_keep_type is (CARRY_NOT_KEEP, CARRY_KEEP);
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type branch_condition is (NOP, BNC, BEQ, BNE, BLT, BLE, BGT, BGE);
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type transfer_size is (WORD, HALFWORD, BYTE);
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type ctrl_execution is record
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alu_op : alu_operation;
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alu_src_a : src_type_a;
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alu_src_b : src_type_b;
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operation : std_logic;
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carry : carry_type;
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carry_keep : carry_keep_type;
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branch_cond : branch_condition;
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delay : std_logic;
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end record;
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type ctrl_memory is record
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mem_write : std_logic;
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mem_read : std_logic;
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transfer_size : transfer_size;
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end record;
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type ctrl_memory_writeback_type is record
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mem_read : std_logic;
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transfer_size : transfer_size;
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end record;
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type forward_type is record
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reg_d : std_logic_vector(CFG_GPRF_SIZE - 1 downto 0);
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reg_write : std_logic;
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end record;
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type imem_in_type is record
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dat_i : std_logic_vector(CFG_IMEM_WIDTH - 1 downto 0);
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end record;
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type imem_out_type is record
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adr_o : std_logic_vector(CFG_IMEM_SIZE - 1 downto 0);
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ena_o : std_logic;
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end record;
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type fetch_in_type is record
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hazard : std_logic;
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branch : std_logic;
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branch_target : std_logic_vector(CFG_IMEM_SIZE - 1 downto 0);
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end record;
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type fetch_out_type is record
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program_counter : std_logic_vector(CFG_IMEM_SIZE - 1 downto 0);
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end record;
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type gprf_out_type is record
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dat_a_o : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0);
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dat_b_o : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0);
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dat_d_o : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0);
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end record;
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type decode_in_type is record
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program_counter : std_logic_vector(CFG_IMEM_SIZE - 1 downto 0);
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instruction : std_logic_vector(CFG_IMEM_WIDTH - 1 downto 0);
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ctrl_wrb : forward_type;
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ctrl_mem_wrb : ctrl_memory_writeback_type;
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mem_result : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0);
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alu_result : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0);
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interrupt : std_logic;
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flush_id : std_logic;
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end record;
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type decode_out_type is record
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reg_a : std_logic_vector(CFG_GPRF_SIZE - 1 downto 0);
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reg_b : std_logic_vector(CFG_GPRF_SIZE - 1 downto 0);
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imm : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0);
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program_counter : std_logic_vector(CFG_IMEM_SIZE - 1 downto 0);
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hazard : std_logic;
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ctrl_ex : ctrl_execution;
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ctrl_mem : ctrl_memory;
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ctrl_wrb : forward_type;
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fwd_dec_result : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0);
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fwd_dec : forward_type;
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end record;
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type gprf_in_type is record
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adr_a_i : std_logic_vector(CFG_GPRF_SIZE - 1 downto 0);
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adr_b_i : std_logic_vector(CFG_GPRF_SIZE - 1 downto 0);
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adr_d_i : std_logic_vector(CFG_GPRF_SIZE - 1 downto 0);
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dat_w_i : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0);
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adr_w_i : std_logic_vector(CFG_GPRF_SIZE - 1 downto 0);
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wre_i : std_logic;
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end record;
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type execute_out_type is record
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alu_result : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0);
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dat_d : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0);
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branch : std_logic;
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program_counter : std_logic_vector(CFG_IMEM_SIZE - 1 downto 0);
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flush_id : std_logic;
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ctrl_mem : ctrl_memory;
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ctrl_wrb : forward_type;
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end record;
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type execute_in_type is record
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reg_a : std_logic_vector(CFG_GPRF_SIZE - 1 downto 0);
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dat_a : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0);
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reg_b : std_logic_vector(CFG_GPRF_SIZE - 1 downto 0);
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dat_b : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0);
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dat_d : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0);
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imm : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0);
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program_counter : std_logic_vector(CFG_IMEM_SIZE - 1 downto 0);
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fwd_dec : forward_type;
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fwd_dec_result : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0);
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fwd_mem : forward_type;
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ctrl_ex : ctrl_execution;
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ctrl_mem : ctrl_memory;
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ctrl_wrb : forward_type;
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ctrl_mem_wrb : ctrl_memory_writeback_type;
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mem_result : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0);
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alu_result : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0);
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end record;
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type mem_in_type is record
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dat_d : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0);
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alu_result : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0);
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mem_result : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0);
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program_counter : std_logic_vector(CFG_IMEM_SIZE - 1 downto 0);
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branch : std_logic;
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ctrl_mem : ctrl_memory;
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ctrl_wrb : forward_type;
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end record;
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takar |
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takar |
type mem_out_type is record
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alu_result : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0);
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ctrl_wrb : forward_type;
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ctrl_mem_wrb : ctrl_memory_writeback_type;
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end record;
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takar |
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type dmem_in_type is record
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dat_i : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0);
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ena_i : std_logic;
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end record;
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takar |
type dmem_out_type is record
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dat_o : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0);
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adr_o : std_logic_vector(CFG_DMEM_SIZE - 1 downto 0);
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sel_o : std_logic_vector(3 downto 0);
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we_o : std_logic;
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ena_o : std_logic;
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end record;
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takar |
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type dmem_in_array_type is array(natural range <>) of dmem_in_type;
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type dmem_out_array_type is array(natural range <>) of dmem_out_type;
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takar |
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-- WB-master inputs from the wb-slaves
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type wb_mst_in_type is record
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clk_i : std_logic; -- master clock input
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rst_i : std_logic; -- synchronous active high reset
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dat_i : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0); -- databus input
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ack_i : std_logic; -- buscycle acknowledge input
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int_i : std_logic; -- interrupt request input
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end record;
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takar |
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-- WB-master outputs to the wb-slaves
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type wb_mst_out_type is record
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adr_o : std_logic_vector(CFG_DMEM_SIZE - 1 downto 0); -- address bits
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dat_o : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0); -- databus output
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we_o : std_logic; -- write enable output
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stb_o : std_logic; -- strobe signals
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sel_o : std_logic_vector(3 downto 0); -- select output array
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cyc_o : std_logic; -- valid BUS cycle output
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end record;
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takar |
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-- WB-slave inputs, from the WB-master
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takar |
type wb_slv_in_type is record
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clk_i : std_logic; -- master clock input
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rst_i : std_logic; -- synchronous active high reset
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adr_i : std_logic_vector(CFG_DMEM_SIZE - 1 downto 0); -- address bits
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dat_i : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0); -- Databus input
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we_i : std_logic; -- Write enable input
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stb_i : std_logic; -- strobe signals / core select signal
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sel_i : std_logic_vector(3 downto 0); -- select output array
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cyc_i : std_logic; -- valid BUS cycle input
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end record;
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takar |
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-- WB-slave outputs to the WB-master
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takar |
type wb_slv_out_type is record
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dat_o : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0); -- Databus output
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ack_o : std_logic; -- Bus cycle acknowledge output
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int_o : std_logic; -- interrupt request output
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end record;
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takar |
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----------------------------------------------------------------------------------------------
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-- COMPONENTS USED IN MB-LITE
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----------------------------------------------------------------------------------------------
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takar |
component core
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generic (
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G_INTERRUPT : boolean := CFG_INTERRUPT;
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G_USE_HW_MUL : boolean := CFG_USE_HW_MUL;
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G_USE_BARREL : boolean := CFG_USE_BARREL;
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G_DEBUG : boolean := CFG_DEBUG
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);
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port (
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imem_o : out imem_out_type;
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dmem_o : out dmem_out_type;
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imem_i : in imem_in_type;
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dmem_i : in dmem_in_type;
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int_i : in std_logic;
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rst_i : in std_logic;
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clk_i : in std_logic
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);
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end component;
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takar |
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takar |
component core_wb
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generic (
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G_INTERRUPT : boolean := CFG_INTERRUPT;
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G_USE_HW_MUL : boolean := CFG_USE_HW_MUL;
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G_USE_BARREL : boolean := CFG_USE_BARREL;
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G_DEBUG : boolean := CFG_DEBUG
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);
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port (
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imem_o : out imem_out_type;
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wb_o : out wb_mst_out_type;
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imem_i : in imem_in_type;
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wb_i : in wb_mst_in_type
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);
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end component;
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takar |
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takar |
component core_wb_adapter
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port (
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dmem_i : out dmem_in_type;
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wb_o : out wb_mst_out_type;
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dmem_o : in dmem_out_type;
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wb_i : in wb_mst_in_type
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);
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end component;
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2 |
takar |
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8 |
takar |
component core_wb_async_adapter
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port (
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dmem_i : out dmem_in_type;
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wb_o : out wb_mst_out_type;
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dmem_o : in dmem_out_type;
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wb_i : in wb_mst_in_type
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);
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end component;
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takar |
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8 |
takar |
component fetch
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port (
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fetch_o : out fetch_out_type;
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imem_o : out imem_out_type;
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fetch_i : in fetch_in_type;
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rst_i : in std_logic;
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ena_i : in std_logic;
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clk_i : in std_logic
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);
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end component;
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2 |
takar |
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8 |
takar |
component decode
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generic (
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G_INTERRUPT : boolean := CFG_INTERRUPT;
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G_USE_HW_MUL : boolean := CFG_USE_HW_MUL;
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G_USE_BARREL : boolean := CFG_USE_BARREL;
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G_DEBUG : boolean := CFG_DEBUG
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);
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port (
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decode_o : out decode_out_type;
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gprf_o : out gprf_out_type;
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decode_i : in decode_in_type;
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ena_i : in std_logic;
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|
rst_i : in std_logic;
|
306 |
|
|
clk_i : in std_logic
|
307 |
|
|
);
|
308 |
|
|
end component;
|
309 |
2 |
takar |
|
310 |
8 |
takar |
component gprf
|
311 |
|
|
port (
|
312 |
|
|
gprf_o : out gprf_out_type;
|
313 |
|
|
gprf_i : in gprf_in_type;
|
314 |
|
|
ena_i : in std_logic;
|
315 |
|
|
clk_i : in std_logic
|
316 |
|
|
);
|
317 |
|
|
end component;
|
318 |
2 |
takar |
|
319 |
8 |
takar |
component execute
|
320 |
|
|
generic (
|
321 |
|
|
G_USE_HW_MUL : boolean := CFG_USE_HW_MUL;
|
322 |
|
|
G_USE_BARREL : boolean := CFG_USE_BARREL
|
323 |
|
|
);
|
324 |
|
|
port (
|
325 |
|
|
exec_o : out execute_out_type;
|
326 |
|
|
exec_i : in execute_in_type;
|
327 |
|
|
ena_i : in std_logic;
|
328 |
|
|
rst_i : in std_logic;
|
329 |
|
|
clk_i : in std_logic
|
330 |
|
|
);
|
331 |
|
|
end component;
|
332 |
2 |
takar |
|
333 |
8 |
takar |
component mem
|
334 |
|
|
port (
|
335 |
|
|
mem_o : out mem_out_type;
|
336 |
|
|
dmem_o : out dmem_out_type;
|
337 |
|
|
mem_i : in mem_in_type;
|
338 |
|
|
ena_i : in std_logic;
|
339 |
|
|
rst_i : in std_logic;
|
340 |
|
|
clk_i : in std_logic
|
341 |
|
|
);
|
342 |
|
|
end component;
|
343 |
2 |
takar |
|
344 |
8 |
takar |
component core_address_decoder
|
345 |
|
|
generic (
|
346 |
|
|
G_NUM_SLAVES : positive := CFG_NUM_SLAVES
|
347 |
|
|
);
|
348 |
|
|
port (
|
349 |
|
|
m_dmem_i : out dmem_in_type;
|
350 |
|
|
s_dmem_o : out dmem_out_array_type;
|
351 |
|
|
m_dmem_o : in dmem_out_type;
|
352 |
|
|
s_dmem_i : in dmem_in_array_type;
|
353 |
|
|
clk_i : in std_logic
|
354 |
|
|
);
|
355 |
|
|
end component;
|
356 |
2 |
takar |
----------------------------------------------------------------------------------------------
|
357 |
|
|
-- FUNCTIONS USED IN MB-LITE
|
358 |
|
|
----------------------------------------------------------------------------------------------
|
359 |
|
|
|
360 |
8 |
takar |
function select_register_data (reg_dat, reg, wb_dat : std_logic_vector; write : std_logic) return std_logic_vector;
|
361 |
|
|
function forward_condition (reg_write : std_logic; reg_a, reg_d : std_logic_vector) return std_logic;
|
362 |
|
|
function align_mem_load (data : std_logic_vector; size : transfer_size; address : std_logic_vector) return std_logic_vector;
|
363 |
|
|
function align_mem_store (data : std_logic_vector; size : transfer_size) return std_logic_vector;
|
364 |
|
|
function decode_mem_store (address : std_logic_vector(1 downto 0); size : transfer_size) return std_logic_vector;
|
365 |
2 |
takar |
|
366 |
8 |
takar |
end core_Pkg;
|
367 |
2 |
takar |
|
368 |
8 |
takar |
package body core_Pkg is
|
369 |
2 |
takar |
|
370 |
|
|
-- This function select the register value:
|
371 |
|
|
-- A) zero
|
372 |
|
|
-- B) bypass value read from register file
|
373 |
|
|
-- C) value from register file
|
374 |
8 |
takar |
function select_register_data (reg_dat, reg, wb_dat : std_logic_vector; write : std_logic) return std_logic_vector is
|
375 |
|
|
variable tmp : std_logic_vector(CFG_DMEM_WIDTH - 1 downto 0);
|
376 |
|
|
begin
|
377 |
|
|
if CFG_REG_FORCE_ZERO = true and is_zero(reg) = '1' then
|
378 |
|
|
tmp := (others => '0');
|
379 |
|
|
elsif CFG_REG_FWD_WRB = true and write = '1' then
|
380 |
2 |
takar |
tmp := wb_dat;
|
381 |
8 |
takar |
else
|
382 |
2 |
takar |
tmp := reg_dat;
|
383 |
8 |
takar |
end if;
|
384 |
|
|
return tmp;
|
385 |
|
|
end select_register_data;
|
386 |
2 |
takar |
|
387 |
|
|
-- This function checks if a forwarding condition is met. The condition is met of register A and D match
|
388 |
|
|
-- and the signal needs to be written back to the register file.
|
389 |
8 |
takar |
function forward_condition (reg_write : std_logic; reg_a, reg_d : std_logic_vector ) return std_logic is
|
390 |
|
|
begin
|
391 |
|
|
return reg_write and compare(reg_a, reg_d);
|
392 |
|
|
end forward_condition;
|
393 |
2 |
takar |
|
394 |
8 |
takar |
-- This function aligns the memory load operation (Big endian decoding).
|
395 |
|
|
function align_mem_load (data : std_logic_vector; size : transfer_size; address : std_logic_vector ) return std_logic_vector is
|
396 |
|
|
begin
|
397 |
|
|
case size is
|
398 |
|
|
when byte =>
|
399 |
|
|
case address(1 downto 0) is
|
400 |
|
|
when "00" => return C_24_ZEROS & data(31 downto 24);
|
401 |
|
|
when "01" => return C_24_ZEROS & data(23 downto 16);
|
402 |
|
|
when "10" => return C_24_ZEROS & data(15 downto 8);
|
403 |
|
|
when "11" => return C_24_ZEROS & data( 7 downto 0);
|
404 |
|
|
when others => return C_32_ZEROS;
|
405 |
|
|
end case;
|
406 |
|
|
when halfword =>
|
407 |
|
|
case address(1 downto 0) is
|
408 |
|
|
when "00" => return C_16_ZEROS & data(31 downto 16);
|
409 |
|
|
when "10" => return C_16_ZEROS & data(15 downto 0);
|
410 |
|
|
when others => return C_32_ZEROS;
|
411 |
|
|
end case;
|
412 |
|
|
when others =>
|
413 |
|
|
return data;
|
414 |
|
|
end case;
|
415 |
|
|
end align_mem_load;
|
416 |
2 |
takar |
|
417 |
8 |
takar |
-- This function repeats the operand to all positions in a memory store operation.
|
418 |
|
|
function align_mem_store (data : std_logic_vector; size : transfer_size) return std_logic_vector is
|
419 |
|
|
begin
|
420 |
|
|
case size is
|
421 |
|
|
when byte => return data( 7 downto 0) & data( 7 downto 0) & data(7 downto 0) & data(7 downto 0);
|
422 |
|
|
when halfword => return data(15 downto 0) & data(15 downto 0);
|
423 |
|
|
when others => return data;
|
424 |
|
|
end case;
|
425 |
|
|
end align_mem_store;
|
426 |
2 |
takar |
|
427 |
8 |
takar |
-- This function selects the correct bytes for memory writes (Big endian encoding).
|
428 |
|
|
function decode_mem_store (address : std_logic_vector(1 downto 0); size : transfer_size) return std_logic_vector is
|
429 |
|
|
begin
|
430 |
|
|
case size is
|
431 |
|
|
when BYTE =>
|
432 |
|
|
case address is
|
433 |
|
|
when "00" => return "1000";
|
434 |
|
|
when "01" => return "0100";
|
435 |
|
|
when "10" => return "0010";
|
436 |
|
|
when "11" => return "0001";
|
437 |
|
|
when others => return "0000";
|
438 |
|
|
end case;
|
439 |
|
|
when HALFWORD =>
|
440 |
|
|
case address is
|
441 |
|
|
-- Big endian encoding
|
442 |
|
|
when "10" => return "0011";
|
443 |
|
|
when "00" => return "1100";
|
444 |
|
|
when others => return "0000";
|
445 |
|
|
end case;
|
446 |
|
|
when others =>
|
447 |
|
|
return "1111";
|
448 |
|
|
end case;
|
449 |
|
|
end decode_mem_store;
|
450 |
2 |
takar |
|
451 |
8 |
takar |
end core_Pkg;
|