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-------------------------------------------------------------------------------
-- Title : Dual-port RAM for WR core
-- Project : WhiteRabbit
-------------------------------------------------------------------------------
-- File : wrc_dpram.vhd
-- Author : Grzegorz Daniluk
-- Company : Elproma
-- Created : 2011-02-15
-- Last update: 2011-07-18
-- Platform : FPGA-generics
-- Standard : VHDL
-------------------------------------------------------------------------------
-- Description:
-- Dual port RAM from genrams with wishbone interface
--
-------------------------------------------------------------------------------
-- Copyright (c) 2011 Grzegorz Daniluk
-------------------------------------------------------------------------------
-- Revisions :
-- Date Version Author Description
-- 2011-02-15 1.0 greg.d Created
-- 2011-06-09 1.01 twlostow Removed unnecessary generics
-------------------------------------------------------------------------------
library ieee;
use ieee.std_logic_1164.all;
library work;
use work.genram_pkg.all;
entity wrc_dpram is
generic(
g_size : natural := 16384; -- 16 * 32bit = 64kB
g_init_file : string := ""
);
port(
clk_i : in std_logic;
rst_n_i : in std_logic;
--PORT A (Wishbone)
wb_addr_i : in std_logic_vector(f_log2_size(g_size)-1 downto 0);
wb_data_i : in std_logic_vector(31 downto 0);
wb_data_o : out std_logic_vector(31 downto 0);
wb_sel_i : in std_logic_vector(3 downto 0);
wb_cyc_i : in std_logic;
wb_stb_i : in std_logic;
wb_we_i : in std_logic;
wb_ack_o : out std_logic;
--PORT B (miniNIC)
mem_addr_i : in std_logic_vector(f_log2_size(g_size)-1 downto 0);
mem_data_i : in std_logic_vector(31 downto 0);
mem_data_o : out std_logic_vector(31 downto 0);
mem_wr_i : in std_logic
);
end wrc_dpram;
architecture struct of wrc_dpram is
signal s_wb_ack_o : std_logic;
signal muxed_we : std_logic;
signal s_bwea : std_logic_vector(3 downto 0);
signal s_bweb : std_logic_vector(3 downto 0);
begin
wb_ack_o <= s_wb_ack_o;
DPRAM : generic_dpram
generic map(
-- standard parameters
g_data_width => 32,
g_size => g_size,
g_with_byte_enable => true,
g_addr_conflict_resolution => "read_first",
g_init_file => g_init_file,
g_dual_clock => false
)
port map(
rst_n_i => rst_n_i,
-- Port A
clka_i => clk_i,
bwea_i => s_bwea,
wea_i => muxed_we, --wb_we_i,
aa_i => wb_addr_i,
da_i => wb_data_i,
qa_o => wb_data_o,
-- Port B
clkb_i => clk_i,
bweb_i => s_bweb,
web_i => mem_wr_i,
ab_i => mem_addr_i,
db_i => mem_data_i,
qb_o => mem_data_o
);
s_bwea <= wb_sel_i when (wb_we_i = '1' and wb_stb_i = '1' and wb_cyc_i = '1') else "0000";
s_bweb <= (others => mem_wr_i);
muxed_we <= wb_we_i when (wb_stb_i='1' and wb_cyc_i='1') else '0';
process(clk_i)
begin
if(rising_edge(clk_i)) then
if(rst_n_i = '0') then
s_wb_ack_o <= '0';
else
if(s_wb_ack_o = '1') then
s_wb_ack_o <= '0';
else
s_wb_ack_o <= wb_cyc_i and wb_stb_i;
end if;
end if;
end if;
end process;
end struct;