Subversion Repositories lxp32

---------------------------------------------------------------------

-- LXP32C CPU top-level module (C-series, with instruction cache)

--

-- Part of the LXP32 CPU

--

-- Copyright (c) 2016 by Alex I. Kuznetsov

--

-- This version uses Wishbone B3 interface for the instruction bus

-- (IBUS). It is designed for high-latency program memory, such as

-- external SDRAM chips.

--

-- Parameters:

--     DBUS_RMW:           Use RMW cycle instead of SEL_O() signal

--                         for byte-granular access to data bus

--     DIVIDER_EN:         enable divider

--     IBUS_BURST_SIZE:    size of the burst

--     IBUS_PREFETCH_SIZE: initiate read burst if number of words

--                         left in the buffer is less than specified

--     MUL_ARCH:           multiplier architecture ("dsp", "opt"

--                         or "seq")

--     START_ADDR:         address in program memory where execution

--                         starts

---------------------------------------------------------------------

library ieee;

use ieee.std_logic_1164.all;

entity lxp32c_top is

        generic(

                DBUS_RMW: boolean:=false;

                DIVIDER_EN: boolean:=true;

                IBUS_BURST_SIZE: integer:=16;

                IBUS_PREFETCH_SIZE: integer:=32;

                MUL_ARCH: string:="dsp";

                START_ADDR: std_logic_vector(31 downto 0):=(others=>'0')

        );

        port(

                clk_i: in std_logic;

                rst_i: in std_logic;

                ibus_cyc_o: out std_logic;

                ibus_stb_o: out std_logic;

                ibus_cti_o: out std_logic_vector(2 downto 0);

                ibus_bte_o: out std_logic_vector(1 downto 0);

                ibus_ack_i: in std_logic;

                ibus_adr_o: out std_logic_vector(29 downto 0);

                ibus_dat_i: in std_logic_vector(31 downto 0);

                dbus_cyc_o: out std_logic;

                dbus_stb_o: out std_logic;

                dbus_we_o: out std_logic;

                dbus_sel_o: out std_logic_vector(3 downto 0);

                dbus_ack_i: in std_logic;

                dbus_adr_o: out std_logic_vector(31 downto 2);

                dbus_dat_o: out std_logic_vector(31 downto 0);

                dbus_dat_i: in std_logic_vector(31 downto 0);

                irq_i: in std_logic_vector(7 downto 0)

        );

end entity;

architecture rtl of lxp32c_top is

signal lli_re: std_logic;

signal lli_adr: std_logic_vector(29 downto 0);

signal lli_dat: std_logic_vector(31 downto 0);

signal lli_busy: std_logic;

begin

cpu_inst: entity work.lxp32_cpu(rtl)

        generic map(

                DBUS_RMW=>DBUS_RMW,

                DIVIDER_EN=>DIVIDER_EN,

                MUL_ARCH=>MUL_ARCH,

                START_ADDR=>START_ADDR

        )

        port map(

                clk_i=>clk_i,

                rst_i=>rst_i,

                lli_re_o=>lli_re,

                lli_adr_o=>lli_adr,

                lli_dat_i=>lli_dat,

                lli_busy_i=>lli_busy,

                dbus_cyc_o=>dbus_cyc_o,

                dbus_stb_o=>dbus_stb_o,

                dbus_we_o=>dbus_we_o,

                dbus_sel_o=>dbus_sel_o,

                dbus_ack_i=>dbus_ack_i,

                dbus_adr_o=>dbus_adr_o,

                dbus_dat_o=>dbus_dat_o,

                dbus_dat_i=>dbus_dat_i,

                irq_i=>irq_i

        );

icache_inst: entity work.lxp32_icache(rtl)

        generic map(

                BURST_SIZE=>IBUS_BURST_SIZE,

                PREFETCH_SIZE=>IBUS_PREFETCH_SIZE

        )

        port map(

                clk_i=>clk_i,

                rst_i=>rst_i,

                lli_re_i=>lli_re,

                lli_adr_i=>lli_adr,

                lli_dat_o=>lli_dat,

                lli_busy_o=>lli_busy,

                wbm_cyc_o=>ibus_cyc_o,

                wbm_stb_o=>ibus_stb_o,

                wbm_cti_o=>ibus_cti_o,

                wbm_bte_o=>ibus_bte_o,

                wbm_ack_i=>ibus_ack_i,

                wbm_adr_o=>ibus_adr_o,

                wbm_dat_i=>ibus_dat_i

        );

end architecture;