Subversion Repositories neorv32

-- #################################################################################################

-- # << NEORV32 - Processor Top Entity with AvalonMM Compatible Master Interface >>                #

-- # ********************************************************************************************* #

-- # (c) "AvalonMM", "NIOS-2", "Qsys", "MegaWizard"  and "Platform Designer"                       # 

-- # are trademarks of Intel                                                                       #

-- # ********************************************************************************************* #

-- # BSD 3-Clause License                                                                          #

-- #                                                                                               #

-- # Copyright (c) 2021, Stephan Nolting. All rights reserved.                                     #

-- #                                                                                               #

-- # Redistribution and use in source and binary forms, with or without modification, are          #

-- # permitted provided that the following conditions are met:                                     #

-- #                                                                                               #

-- # 1. Redistributions of source code must retain the above copyright notice, this list of        #

-- #    conditions and the following disclaimer.                                                   #

-- #                                                                                               #

-- # 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        #

-- #    provided with the distribution.                                                            #

-- #                                                                                               #

-- # 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      #

-- #    permission.                                                                                #

-- #                                                                                               #

-- # 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               #

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-- # ********************************************************************************************* #

-- # The NEORV32 Processor - https://github.com/stnolting/neorv32              (c) Stephan Nolting #

-- #################################################################################################

library ieee;

use ieee.std_logic_1164.all;

use ieee.numeric_std.all;

library neorv32;

use neorv32.neorv32_package.all;

entity neorv32_top_avalonmm is

  generic (

    -- General --

    CLOCK_FREQUENCY              : natural;           -- clock frequency of clk_i in Hz

    HW_THREAD_ID                 : natural := 0;      -- hardware thread id (32-bit)

    INT_BOOTLOADER_EN            : boolean := false;  -- boot configuration: true = boot explicit bootloader; false = boot from int/ext (I)MEM

    -- On-Chip Debugger (OCD) --

    ON_CHIP_DEBUGGER_EN          : boolean := false;  -- implement on-chip debugger

    -- RISC-V CPU Extensions --

    CPU_EXTENSION_RISCV_A        : boolean := false;  -- implement atomic extension?

    CPU_EXTENSION_RISCV_B        : boolean := false;  -- implement bit-manipulation extension?

    CPU_EXTENSION_RISCV_C        : boolean := false;  -- implement compressed extension?

    CPU_EXTENSION_RISCV_E        : boolean := false;  -- implement embedded RF extension?

    CPU_EXTENSION_RISCV_M        : boolean := false;  -- implement mul/div extension?

    CPU_EXTENSION_RISCV_U        : boolean := false;  -- implement user mode extension?

    CPU_EXTENSION_RISCV_Zfinx    : boolean := false;  -- implement 32-bit floating-point extension (using INT regs!)

    CPU_EXTENSION_RISCV_Zicsr    : boolean := true;   -- implement CSR system?

    CPU_EXTENSION_RISCV_Zicntr   : boolean := true;   -- implement base counters?

    CPU_EXTENSION_RISCV_Zihpm    : boolean := false;  -- implement hardware performance monitors?

    CPU_EXTENSION_RISCV_Zifencei : boolean := false;  -- implement instruction stream sync.?

    CPU_EXTENSION_RISCV_Zmmul    : boolean := false;  -- implement multiply-only M sub-extension?

    -- Extension Options --

    FAST_MUL_EN                  : boolean := false;  -- use DSPs for M extension's multiplier

    FAST_SHIFT_EN                : boolean := false;  -- use barrel shifter for shift operations

    CPU_CNT_WIDTH                : natural := 64;     -- total width of CPU cycle and instret counters (0..64)

    CPU_IPB_ENTRIES              : natural := 2;      -- entries is instruction prefetch buffer, has to be a power of 2

    -- Physical Memory Protection (PMP) --

    PMP_NUM_REGIONS              : natural := 0;      -- number of regions (0..64)

    PMP_MIN_GRANULARITY          : natural := 64*1024; -- minimal region granularity in bytes, has to be a power of 2, min 8 bytes

    -- Hardware Performance Monitors (HPM) --

    HPM_NUM_CNTS                 : natural := 0;      -- number of implemented HPM counters (0..29)

    HPM_CNT_WIDTH                : natural := 40;     -- total size of HPM counters (0..64)

    -- Internal Instruction memory (IMEM) --

    MEM_INT_IMEM_EN              : boolean := false;  -- implement processor-internal instruction memory

    MEM_INT_IMEM_SIZE            : natural := 16*1024; -- size of processor-internal instruction memory in bytes

    -- Internal Data memory (DMEM) --

    MEM_INT_DMEM_EN              : boolean := false;  -- implement processor-internal data memory

    MEM_INT_DMEM_SIZE            : natural := 8*1024; -- size of processor-internal data memory in bytes

    -- Internal Cache memory (iCACHE) --

    ICACHE_EN                    : boolean := false;  -- implement instruction cache

    ICACHE_NUM_BLOCKS            : natural := 4;      -- i-cache: number of blocks (min 1), has to be a power of 2

    ICACHE_BLOCK_SIZE            : natural := 64;     -- i-cache: block size in bytes (min 4), has to be a power of 2

    ICACHE_ASSOCIATIVITY         : natural := 1;      -- i-cache: associativity / number of sets (1=direct_mapped), has to be a power of 2

    -- Stream link interface (SLINK) --

    SLINK_NUM_TX                 : natural := 0;      -- number of TX links (0..8)

    SLINK_NUM_RX                 : natural := 0;      -- number of TX links (0..8)

    SLINK_TX_FIFO                : natural := 1;      -- TX fifo depth, has to be a power of two

    SLINK_RX_FIFO                : natural := 1;      -- RX fifo depth, has to be a power of two

    -- External Interrupts Controller (XIRQ) --

    XIRQ_NUM_CH                  : natural := 0;      -- number of external IRQ channels (0..32)

    XIRQ_TRIGGER_TYPE            : std_ulogic_vector(31 downto 0) := x"ffffffff"; -- trigger type: 0=level, 1=edge

    XIRQ_TRIGGER_POLARITY        : std_ulogic_vector(31 downto 0) := x"ffffffff"; -- trigger polarity: 0=low-level/falling-edge, 1=high-level/rising-edge

    -- Processor peripherals --

    IO_GPIO_EN                   : boolean := false;  -- implement general purpose input/output port unit (GPIO)?

    IO_MTIME_EN                  : boolean := false;  -- implement machine system timer (MTIME)?

    IO_UART0_EN                  : boolean := false;  -- implement primary universal asynchronous receiver/transmitter (UART0)?

    IO_UART0_RX_FIFO             : natural := 1;      -- RX fifo depth, has to be a power of two, min 1

    IO_UART0_TX_FIFO             : natural := 1;      -- TX fifo depth, has to be a power of two, min 1

    IO_UART1_EN                  : boolean := false;  -- implement secondary universal asynchronous receiver/transmitter (UART1)?

    IO_UART1_RX_FIFO             : natural := 1;      -- RX fifo depth, has to be a power of two, min 1

    IO_UART1_TX_FIFO             : natural := 1;      -- TX fifo depth, has to be a power of two, min 1

    IO_SPI_EN                    : boolean := false;  -- implement serial peripheral interface (SPI)?

    IO_TWI_EN                    : boolean := false;  -- implement two-wire interface (TWI)?

    IO_PWM_NUM_CH                : natural := 0;      -- number of PWM channels to implement (0..60); 0 = disabled

    IO_WDT_EN                    : boolean := false;  -- implement watch dog timer (WDT)?

    IO_TRNG_EN                   : boolean := false;  -- implement true random number generator (TRNG)?

    IO_CFS_EN                    : boolean := false;  -- implement custom functions subsystem (CFS)?

    IO_CFS_CONFIG                : std_ulogic_vector(31 downto 0) := x"00000000"; -- custom CFS configuration generic

    IO_CFS_IN_SIZE               : positive := 32;    -- size of CFS input conduit in bits

    IO_CFS_OUT_SIZE              : positive := 32;    -- size of CFS output conduit in bits

    IO_NEOLED_EN                 : boolean := false;  -- implement NeoPixel-compatible smart LED interface (NEOLED)?

    IO_NEOLED_TX_FIFO            : natural := 1;      -- NEOLED TX FIFO depth, 1..32k, has to be a power of two

    IO_GPTMR_EN                  : boolean := false   -- implement general purpose timer (GPTMR)?

  );

  port (

    -- Global control --

    clk_i          : in  std_ulogic; -- global clock, rising edge

    rstn_i         : in  std_ulogic; -- global reset, low-active, async

    -- JTAG on-chip debugger interface (available if ON_CHIP_DEBUGGER_EN = true) --

    jtag_trst_i    : in  std_ulogic := 'U'; -- low-active TAP reset (optional)

    jtag_tck_i     : in  std_ulogic := 'U'; -- serial clock

    jtag_tdi_i     : in  std_ulogic := 'U'; -- serial data input

    jtag_tdo_o     : out std_ulogic;        -- serial data output

    jtag_tms_i     : in  std_ulogic := 'U'; -- mode select

    -- AvalonMM interface

    read_o         : out std_logic;

    write_o        : out std_logic;

    waitrequest_i  : in std_logic := '0';

    byteenable_o   : out std_logic_vector(3 downto 0);

    address_o      : out std_logic_vector(31 downto 0);

    writedata_o    : out std_logic_vector(31 downto 0);

    readdata_i     : in std_logic_vector(31 downto 0) := (others => '0');

    -- Advanced memory control signals (available if MEM_EXT_EN = true) --

    fence_o        : out std_ulogic; -- indicates an executed FENCE operation

    fencei_o       : out std_ulogic; -- indicates an executed FENCEI operation

    -- TX stream interfaces (available if SLINK_NUM_TX > 0) --

    slink_tx_dat_o : out sdata_8x32_t; -- output data

    slink_tx_val_o : out std_ulogic_vector(7 downto 0); -- valid output

    slink_tx_rdy_i : in  std_ulogic_vector(7 downto 0) := (others => 'L'); -- ready to send

    -- RX stream interfaces (available if SLINK_NUM_RX > 0) --

    slink_rx_dat_i : in  sdata_8x32_t := (others => (others => 'U')); -- input data

    slink_rx_val_i : in  std_ulogic_vector(7 downto 0) := (others => 'L'); -- valid input

    slink_rx_rdy_o : out std_ulogic_vector(7 downto 0); -- ready to receive

    -- GPIO (available if IO_GPIO_EN = true) --

    gpio_o         : out std_ulogic_vector(63 downto 0); -- parallel output

    gpio_i         : in  std_ulogic_vector(63 downto 0) := (others => 'U'); -- parallel input

    -- primary UART0 (available if IO_UART0_EN = true) --

    uart0_txd_o    : out std_ulogic; -- UART0 send data

    uart0_rxd_i    : in  std_ulogic := 'U'; -- UART0 receive data

    uart0_rts_o    : out std_ulogic; -- hw flow control: UART0.RX ready to receive ("RTR"), low-active, optional

    uart0_cts_i    : in  std_ulogic := 'L'; -- hw flow control: UART0.TX allowed to transmit, low-active, optional

    -- secondary UART1 (available if IO_UART1_EN = true) --

    uart1_txd_o    : out std_ulogic; -- UART1 send data

    uart1_rxd_i    : in  std_ulogic := 'U'; -- UART1 receive data

    uart1_rts_o    : out std_ulogic; -- hw flow control: UART1.RX ready to receive ("RTR"), low-active, optional

    uart1_cts_i    : in  std_ulogic := 'L'; -- hw flow control: UART1.TX allowed to transmit, low-active, optional

    -- SPI (available if IO_SPI_EN = true) --

    spi_sck_o      : out std_ulogic; -- SPI serial clock

    spi_sdo_o      : out std_ulogic; -- controller data out, peripheral data in

    spi_sdi_i      : in  std_ulogic := 'U'; -- controller data in, peripheral data out

    spi_csn_o      : out std_ulogic_vector(07 downto 0); -- chip-select

    -- TWI (available if IO_TWI_EN = true) --

    twi_sda_io     : inout std_logic := 'U'; -- twi serial data line

    twi_scl_io     : inout std_logic := 'U'; -- twi serial clock line

    -- PWM (available if IO_PWM_NUM_CH > 0) --

    pwm_o          : out std_ulogic_vector(IO_PWM_NUM_CH-1 downto 0); -- pwm channels

    -- Custom Functions Subsystem IO (available if IO_CFS_EN = true) --

    cfs_in_i       : in  std_ulogic_vector(IO_CFS_IN_SIZE-1  downto 0) := (others => 'U'); -- custom CFS inputs conduit

    cfs_out_o      : out std_ulogic_vector(IO_CFS_OUT_SIZE-1 downto 0); -- custom CFS outputs conduit

    -- NeoPixel-compatible smart LED interface (available if IO_NEOLED_EN = true) --

    neoled_o       : out std_ulogic; -- async serial data line

    -- System time --

    mtime_i        : in  std_ulogic_vector(63 downto 0) := (others => 'U'); -- current system time from ext. MTIME (if IO_MTIME_EN = false)

    mtime_o        : out std_ulogic_vector(63 downto 0); -- current system time from int. MTIME (if IO_MTIME_EN = true)

    -- External platform interrupts (available if XIRQ_NUM_CH > 0) --

    xirq_i         : in  std_ulogic_vector(XIRQ_NUM_CH-1 downto 0) := (others => 'L'); -- IRQ channels

    -- CPU interrupts --

    mtime_irq_i    : in  std_ulogic := 'L'; -- machine timer interrupt, available if IO_MTIME_EN = false

    msw_irq_i      : in  std_ulogic := 'L'; -- machine software interrupt

    mext_irq_i     : in  std_ulogic := 'L'  -- machine external interrupt

  );

end neorv32_top_avalonmm;

architecture neorv32_top_avalonmm_rtl of neorv32_top_avalonmm is

  -- Wishbone bus interface (available if MEM_EXT_EN = true) --

  signal wb_tag_o  : std_ulogic_vector(02 downto 0); -- request tag

  signal wb_adr_o  : std_ulogic_vector(31 downto 0); -- address

  signal wb_dat_i  : std_ulogic_vector(31 downto 0) := (others => 'U'); -- read data

  signal wb_dat_o  : std_ulogic_vector(31 downto 0); -- write data

  signal wb_we_o   : std_ulogic; -- read/write

  signal wb_sel_o  : std_ulogic_vector(03 downto 0); -- byte enable

  signal wb_stb_o  : std_ulogic; -- strobe

  signal wb_cyc_o  : std_ulogic; -- valid cycle

  signal wb_lock_o : std_ulogic; -- exclusive access request

  signal wb_ack_i  : std_ulogic := 'L'; -- transfer acknowledge

  signal wb_err_i  : std_ulogic := 'L'; -- transfer error

begin

  neorv32_top_map : neorv32_top

  generic map (

    -- General --

    CLOCK_FREQUENCY => CLOCK_FREQUENCY,

    HW_THREAD_ID => HW_THREAD_ID,

    INT_BOOTLOADER_EN => INT_BOOTLOADER_EN,

    -- On-Chip Debugger (OCD) --

    ON_CHIP_DEBUGGER_EN => ON_CHIP_DEBUGGER_EN,

    -- RISC-V CPU Extensions --

    CPU_EXTENSION_RISCV_A => CPU_EXTENSION_RISCV_A,

    CPU_EXTENSION_RISCV_B => CPU_EXTENSION_RISCV_B,

    CPU_EXTENSION_RISCV_C => CPU_EXTENSION_RISCV_C,

    CPU_EXTENSION_RISCV_E => CPU_EXTENSION_RISCV_E,

    CPU_EXTENSION_RISCV_M => CPU_EXTENSION_RISCV_M,

    CPU_EXTENSION_RISCV_U => CPU_EXTENSION_RISCV_U,

    CPU_EXTENSION_RISCV_Zfinx => CPU_EXTENSION_RISCV_Zfinx,

    CPU_EXTENSION_RISCV_Zicsr => CPU_EXTENSION_RISCV_Zicsr,

    CPU_EXTENSION_RISCV_Zicntr => CPU_EXTENSION_RISCV_Zicntr,

    CPU_EXTENSION_RISCV_Zihpm => CPU_EXTENSION_RISCV_Zihpm,

    CPU_EXTENSION_RISCV_Zifencei => CPU_EXTENSION_RISCV_Zifencei,

    CPU_EXTENSION_RISCV_Zmmul => CPU_EXTENSION_RISCV_Zmmul,

    -- Extension Options --

    FAST_MUL_EN => FAST_MUL_EN,

    FAST_SHIFT_EN => FAST_SHIFT_EN,

    CPU_CNT_WIDTH => CPU_CNT_WIDTH,

    CPU_IPB_ENTRIES => CPU_IPB_ENTRIES,

    -- Physical Memory Protection (PMP) --

    PMP_NUM_REGIONS => PMP_NUM_REGIONS,

    PMP_MIN_GRANULARITY => PMP_MIN_GRANULARITY,

    -- Hardware Performance Monitors (HPM) --

    HPM_NUM_CNTS => HPM_NUM_CNTS,

    HPM_CNT_WIDTH => HPM_CNT_WIDTH,

    -- Internal Instruction memory (IMEM) --

    MEM_INT_IMEM_EN => MEM_INT_IMEM_EN,

    MEM_INT_IMEM_SIZE => MEM_INT_IMEM_SIZE,

    -- Internal Data memory (DMEM) --

    MEM_INT_DMEM_EN => MEM_INT_IMEM_EN,

    MEM_INT_DMEM_SIZE => MEM_INT_DMEM_SIZE,

    -- Internal Cache memory (iCACHE) --

    ICACHE_EN => ICACHE_EN,

    ICACHE_NUM_BLOCKS => ICACHE_NUM_BLOCKS,

    ICACHE_BLOCK_SIZE => ICACHE_BLOCK_SIZE,

    ICACHE_ASSOCIATIVITY => ICACHE_ASSOCIATIVITY,

    -- External memory interface (WISHBONE) --

    MEM_EXT_EN => true,

    MEM_EXT_TIMEOUT => 0,

    MEM_EXT_PIPE_MODE => false,

    MEM_EXT_BIG_ENDIAN => false,

    MEM_EXT_ASYNC_RX => false,

    -- Stream link interface (SLINK) --

    SLINK_NUM_TX => SLINK_NUM_TX,

    SLINK_NUM_RX => SLINK_NUM_RX,

    SLINK_TX_FIFO => SLINK_TX_FIFO,

    SLINK_RX_FIFO => SLINK_RX_FIFO,

    -- External Interrupts Controller (XIRQ) --

    XIRQ_NUM_CH => XIRQ_NUM_CH,

    XIRQ_TRIGGER_TYPE => XIRQ_TRIGGER_TYPE,

    XIRQ_TRIGGER_POLARITY => XIRQ_TRIGGER_POLARITY,

    -- Processor peripherals --

    IO_GPIO_EN => IO_GPIO_EN,

    IO_MTIME_EN => IO_MTIME_EN,

    IO_UART0_EN => IO_UART0_EN,

    IO_UART0_RX_FIFO => IO_UART0_RX_FIFO,

    IO_UART0_TX_FIFO => IO_UART0_TX_FIFO,

    IO_UART1_EN => IO_UART1_EN,

    IO_UART1_RX_FIFO => IO_UART1_RX_FIFO,

    IO_UART1_TX_FIFO => IO_UART1_TX_FIFO,

    IO_SPI_EN => IO_SPI_EN,

    IO_TWI_EN => IO_TWI_EN,

    IO_PWM_NUM_CH => IO_PWM_NUM_CH,

    IO_WDT_EN => IO_WDT_EN,

    IO_TRNG_EN => IO_TRNG_EN,

    IO_CFS_EN => IO_CFS_EN,

    IO_CFS_CONFIG => IO_CFS_CONFIG,

    IO_CFS_IN_SIZE => IO_CFS_IN_SIZE,

    IO_CFS_OUT_SIZE => IO_CFS_OUT_SIZE,

    IO_NEOLED_EN => IO_NEOLED_EN,

    IO_NEOLED_TX_FIFO => IO_NEOLED_TX_FIFO,

    IO_GPTMR_EN => IO_GPTMR_EN

    )

  port map (

    -- Global control --

    clk_i => clk_i,

    rstn_i => rstn_i,

    -- JTAG on-chip debugger interface (available if ON_CHIP_DEBUGGER_EN = true) --

    jtag_trst_i => jtag_trst_i,

    jtag_tck_i => jtag_tck_i,

    jtag_tdi_i => jtag_tdi_i,

    jtag_tdo_o => jtag_tdo_o,

    jtag_tms_i => jtag_tms_i,

    -- Wishbone bus interface (available if MEM_EXT_EN = true) --

    wb_tag_o => wb_tag_o,

    wb_adr_o => wb_adr_o,

    wb_dat_i => wb_dat_i,

    wb_dat_o => wb_dat_o,

    wb_we_o => wb_we_o,

    wb_sel_o => wb_sel_o,

    wb_stb_o => wb_stb_o,

    wb_cyc_o => wb_cyc_o,

    wb_lock_o => wb_lock_o,

    wb_ack_i => wb_ack_i,

    wb_err_i => wb_err_i,

    -- Advanced memory control signals (available if MEM_EXT_EN = true) --

    fence_o => fence_o,

    fencei_o => fencei_o,

    -- TX stream interfaces (available if SLINK_NUM_TX > 0) --

    slink_tx_dat_o => slink_tx_dat_o,

    slink_tx_val_o => slink_tx_val_o,

    slink_tx_rdy_i => slink_tx_rdy_i,

    -- RX stream interfaces (available if SLINK_NUM_RX > 0) --

    slink_rx_dat_i => slink_rx_dat_i,

    slink_rx_val_i => slink_rx_val_i,

    slink_rx_rdy_o => slink_rx_rdy_o,

    -- GPIO (available if IO_GPIO_EN = true) --

    gpio_o => gpio_o,

    gpio_i => gpio_i,

    -- primary UART0 (available if IO_UART0_EN = true) --

    uart0_txd_o => uart0_txd_o,

    uart0_rxd_i => uart0_rxd_i,

    uart0_rts_o => uart0_rts_o,

    uart0_cts_i => uart0_cts_i,

    -- secondary UART1 (available if IO_UART1_EN = true) --

    uart1_txd_o => uart1_txd_o,

    uart1_rxd_i => uart1_rxd_i,

    uart1_rts_o => uart1_rts_o,

    uart1_cts_i => uart1_cts_i,

    -- SPI (available if IO_SPI_EN = true) --

    spi_sck_o => spi_sck_o,

    spi_sdo_o => spi_sdo_o,

    spi_sdi_i => spi_sdi_i,

    spi_csn_o => spi_csn_o,

    -- TWI (available if IO_TWI_EN = true) --

    twi_sda_io => twi_sda_io,

    twi_scl_io => twi_scl_io,

    -- PWM (available if IO_PWM_NUM_CH > 0) --

    pwm_o => pwm_o,

    -- Custom Functions Subsystem IO (available if IO_CFS_EN = true) --

    cfs_in_i => cfs_in_i,

    cfs_out_o => cfs_out_o,

    -- NeoPixel-compatible smart LED interface (available if IO_NEOLED_EN = true) --

    neoled_o => neoled_o,

    -- System time --

    mtime_i => mtime_i,

    mtime_o => mtime_o,

    -- External platform interrupts (available if XIRQ_NUM_CH > 0) --

    xirq_i => xirq_i,

    -- CPU interrupts --

    mtime_irq_i => mtime_irq_i,

    msw_irq_i => msw_irq_i,

    mext_irq_i => mext_irq_i

  );

  -- Wishbone to AvalonMM bridge

  read_o <= '1' when (wb_stb_o = '1' and wb_we_o = '0') else '0';

  write_o <= '1' when (wb_stb_o = '1' and wb_we_o = '1') else '0';

  address_o <= std_logic_vector(wb_adr_o);

  writedata_o <= std_logic_vector(wb_dat_o);

  byteenable_o <= std_logic_vector(wb_sel_o);

  wb_dat_i <= std_ulogic_vector(readdata_i);

  wb_ack_i <= not(waitrequest_i);

  wb_err_i <= '0';

end neorv32_top_avalonmm_rtl;