library ieee;
use ieee.std_logic_1164.all;
use ieee.numeric_std.all;
use std.textio.all;
library work;
use work.wishbone_types.all;
entity litedram_wrapper is
generic (
DRAM_ABITS : positive;
DRAM_ALINES : positive
);
port(
-- LiteDRAM generates the system clock and reset
-- from the input clkin
clk_in : in std_ulogic;
rst : in std_ulogic;
system_clk : out std_ulogic;
system_reset : out std_ulogic;
core_alt_reset : out std_ulogic;
pll_locked : out std_ulogic;
-- Wishbone ports:
wb_in : in wishbone_master_out;
wb_out : out wishbone_slave_out;
wb_ctrl_in : in wb_io_master_out;
wb_ctrl_out : out wb_io_slave_out;
wb_ctrl_is_csr : in std_ulogic;
wb_ctrl_is_init : in std_ulogic;
-- Init core serial debug
serial_tx : out std_ulogic;
serial_rx : in std_ulogic;
-- Misc
init_done : out std_ulogic;
init_error : out std_ulogic;
-- DRAM wires
ddram_a : out std_ulogic_vector(DRAM_ALINES-1 downto 0);
ddram_ba : out std_ulogic_vector(2 downto 0);
ddram_ras_n : out std_ulogic;
ddram_cas_n : out std_ulogic;
ddram_we_n : out std_ulogic;
ddram_cs_n : out std_ulogic;
ddram_dm : out std_ulogic_vector(1 downto 0);
ddram_dq : inout std_ulogic_vector(15 downto 0);
ddram_dqs_p : inout std_ulogic_vector(1 downto 0);
ddram_dqs_n : inout std_ulogic_vector(1 downto 0);
ddram_clk_p : out std_ulogic;
ddram_clk_n : out std_ulogic;
ddram_cke : out std_ulogic;
ddram_odt : out std_ulogic;
ddram_reset_n : out std_ulogic
);
end entity litedram_wrapper;
architecture behaviour of litedram_wrapper is
component litedram_core port (
clk : in std_ulogic;
rst : in std_ulogic;
pll_locked : out std_ulogic;
ddram_a : out std_ulogic_vector(DRAM_ALINES-1 downto 0);
ddram_ba : out std_ulogic_vector(2 downto 0);
ddram_ras_n : out std_ulogic;
ddram_cas_n : out std_ulogic;
ddram_we_n : out std_ulogic;
ddram_cs_n : out std_ulogic;
ddram_dm : out std_ulogic_vector(1 downto 0);
ddram_dq : inout std_ulogic_vector(15 downto 0);
ddram_dqs_p : inout std_ulogic_vector(1 downto 0);
ddram_dqs_n : inout std_ulogic_vector(1 downto 0);
ddram_clk_p : out std_ulogic;
ddram_clk_n : out std_ulogic;
ddram_cke : out std_ulogic;
ddram_odt : out std_ulogic;
ddram_reset_n : out std_ulogic;
init_done : out std_ulogic;
init_error : out std_ulogic;
user_clk : out std_ulogic;
user_rst : out std_ulogic;
wb_ctrl_adr : in std_ulogic_vector(29 downto 0);
wb_ctrl_dat_w : in std_ulogic_vector(31 downto 0);
wb_ctrl_dat_r : out std_ulogic_vector(31 downto 0);
wb_ctrl_sel : in std_ulogic_vector(3 downto 0);
wb_ctrl_cyc : in std_ulogic;
wb_ctrl_stb : in std_ulogic;
wb_ctrl_ack : out std_ulogic;
wb_ctrl_we : in std_ulogic;
wb_ctrl_cti : in std_ulogic_vector(2 downto 0);
wb_ctrl_bte : in std_ulogic_vector(1 downto 0);
wb_ctrl_err : out std_ulogic;
user_port_native_0_cmd_valid : in std_ulogic;
user_port_native_0_cmd_ready : out std_ulogic;
user_port_native_0_cmd_we : in std_ulogic;
user_port_native_0_cmd_addr : in std_ulogic_vector(DRAM_ABITS-1 downto 0);
user_port_native_0_wdata_valid : in std_ulogic;
user_port_native_0_wdata_ready : out std_ulogic;
user_port_native_0_wdata_we : in std_ulogic_vector(15 downto 0);
user_port_native_0_wdata_data : in std_ulogic_vector(127 downto 0);
user_port_native_0_rdata_valid : out std_ulogic;
user_port_native_0_rdata_ready : in std_ulogic;
user_port_native_0_rdata_data : out std_ulogic_vector(127 downto 0)
);
end component;
signal user_port0_cmd_valid : std_ulogic;
signal user_port0_cmd_ready : std_ulogic;
signal user_port0_cmd_we : std_ulogic;
signal user_port0_cmd_addr : std_ulogic_vector(DRAM_ABITS-1 downto 0);
signal user_port0_wdata_valid : std_ulogic;
signal user_port0_wdata_ready : std_ulogic;
signal user_port0_wdata_we : std_ulogic_vector(15 downto 0);
signal user_port0_wdata_data : std_ulogic_vector(127 downto 0);
signal user_port0_rdata_valid : std_ulogic;
signal user_port0_rdata_ready : std_ulogic;
signal user_port0_rdata_data : std_ulogic_vector(127 downto 0);
signal ad3 : std_ulogic;
signal wb_ctrl_adr : std_ulogic_vector(29 downto 0);
signal wb_ctrl_dat_w : std_ulogic_vector(31 downto 0);
signal wb_ctrl_dat_r : std_ulogic_vector(31 downto 0);
signal wb_ctrl_sel : std_ulogic_vector(3 downto 0);
signal wb_ctrl_cyc : std_ulogic;
signal wb_ctrl_stb : std_ulogic;
signal wb_ctrl_ack : std_ulogic;
signal wb_ctrl_we : std_ulogic;
signal wb_init_in : wb_io_master_out;
signal wb_init_out : wb_io_slave_out;
type state_t is (CMD, MWRITE, MREAD);
signal state : state_t;
begin
-- alternate core reset address set when DRAM is not initialized.
core_alt_reset <= not init_done;
-- Init code BRAM memory slave
init_ram_0: entity work.dram_init_mem
port map(
clk => system_clk,
wb_in => wb_init_in,
wb_out => wb_init_out
);
--
-- Control bus wishbone: This muxes the wishbone to the CSRs
-- and an internal small one to the init BRAM
--
-- Init DRAM wishbone IN signals
wb_init_in.adr <= wb_ctrl_in.adr;
wb_init_in.dat <= wb_ctrl_in.dat;
wb_init_in.sel <= wb_ctrl_in.sel;
wb_init_in.we <= wb_ctrl_in.we;
wb_init_in.stb <= wb_ctrl_in.stb;
wb_init_in.cyc <= wb_ctrl_in.cyc and wb_ctrl_is_init;
-- DRAM CSR IN signals
wb_ctrl_adr <= x"0000" & wb_ctrl_in.adr(15 downto 2);
wb_ctrl_dat_w <= wb_ctrl_in.dat;
wb_ctrl_sel <= wb_ctrl_in.sel;
wb_ctrl_we <= wb_ctrl_in.we;
wb_ctrl_cyc <= wb_ctrl_in.cyc and wb_ctrl_is_csr;
wb_ctrl_stb <= wb_ctrl_in.stb and wb_ctrl_is_csr;
-- Ctrl bus wishbone OUT signals
wb_ctrl_out.ack <= wb_ctrl_ack when wb_ctrl_is_csr = '1'
else wb_init_out.ack;
wb_ctrl_out.dat <= wb_ctrl_dat_r when wb_ctrl_is_csr = '1'
else wb_init_out.dat;
wb_ctrl_out.stall <= wb_init_out.stall when wb_ctrl_is_init else
'0' when wb_ctrl_in.cyc = '0' else not wb_ctrl_ack;
--
-- Data bus wishbone to LiteDRAM native port
--
-- Address bit 3 selects the top or bottom half of the data
-- bus (64-bit wishbone vs. 128-bit DRAM interface)
--
-- XXX TODO: Figure out how to pipeline this
--
ad3 <= wb_in.adr(3);
-- Wishbone port IN signals
user_port0_cmd_valid <= wb_in.cyc and wb_in.stb when state = CMD else '0';
user_port0_cmd_we <= wb_in.we when state = CMD else '0';
user_port0_wdata_valid <= '1' when state = MWRITE else '0';
user_port0_rdata_ready <= '1' when state = MREAD else '0';
user_port0_cmd_addr <= wb_in.adr(DRAM_ABITS+3 downto 4);
user_port0_wdata_data <= wb_in.dat & wb_in.dat;
user_port0_wdata_we <= wb_in.sel & "00000000" when ad3 = '1' else
"00000000" & wb_in.sel;
-- Wishbone OUT signals
wb_out.ack <= user_port0_wdata_ready when state = MWRITE else
user_port0_rdata_valid when state = MREAD else '0';
wb_out.dat <= user_port0_rdata_data(127 downto 64) when ad3 = '1' else
user_port0_rdata_data(63 downto 0);
-- We don't do pipelining yet.
wb_out.stall <= '0' when wb_in.cyc = '0' else not wb_out.ack;
-- DRAM user port State machine
sm: process(system_clk)
begin
if rising_edge(system_clk) then
if system_reset = '1' then
state <= CMD;
else
case state is
when CMD =>
if (user_port0_cmd_ready and user_port0_cmd_valid) = '1' then
state <= MWRITE when wb_in.we = '1' else MREAD;
end if;
when MWRITE =>
if user_port0_wdata_ready = '1' then
state <= CMD;
end if;
when MREAD =>
if user_port0_rdata_valid = '1' then
state <= CMD;
end if;
end case;
end if;
end if;
end process;
litedram: litedram_core
port map(
clk => clk_in,
rst => rst,
pll_locked => pll_locked,
ddram_a => ddram_a,
ddram_ba => ddram_ba,
ddram_ras_n => ddram_ras_n,
ddram_cas_n => ddram_cas_n,
ddram_we_n => ddram_we_n,
ddram_cs_n => ddram_cs_n,
ddram_dm => ddram_dm,
ddram_dq => ddram_dq,
ddram_dqs_p => ddram_dqs_p,
ddram_dqs_n => ddram_dqs_n,
ddram_clk_p => ddram_clk_p,
ddram_clk_n => ddram_clk_n,
ddram_cke => ddram_cke,
ddram_odt => ddram_odt,
ddram_reset_n => ddram_reset_n,
init_done => init_done,
init_error => init_error,
user_clk => system_clk,
user_rst => system_reset,
wb_ctrl_adr => wb_ctrl_adr,
wb_ctrl_dat_w => wb_ctrl_dat_w,
wb_ctrl_dat_r => wb_ctrl_dat_r,
wb_ctrl_sel => wb_ctrl_sel,
wb_ctrl_cyc => wb_ctrl_cyc,
wb_ctrl_stb => wb_ctrl_stb,
wb_ctrl_ack => wb_ctrl_ack,
wb_ctrl_we => wb_ctrl_we,
wb_ctrl_cti => "000",
wb_ctrl_bte => "00",
wb_ctrl_err => open,
user_port_native_0_cmd_valid => user_port0_cmd_valid,
user_port_native_0_cmd_ready => user_port0_cmd_ready,
user_port_native_0_cmd_we => user_port0_cmd_we,
user_port_native_0_cmd_addr => user_port0_cmd_addr,
user_port_native_0_wdata_valid => user_port0_wdata_valid,
user_port_native_0_wdata_ready => user_port0_wdata_ready,
user_port_native_0_wdata_we => user_port0_wdata_we,
user_port_native_0_wdata_data => user_port0_wdata_data,
user_port_native_0_rdata_valid => user_port0_rdata_valid,
user_port_native_0_rdata_ready => user_port0_rdata_ready,
user_port_native_0_rdata_data => user_port0_rdata_data
);
end architecture behaviour;