Files
FireBee_SVN/vhdl/rtl/vhdl/DDR/DDR_CTRL.vhd
2014-12-22 08:40:35 +00:00

873 lines
39 KiB
VHDL

----------------------------------------------------------------------
---- ----
---- This file is part of the 'Firebee' project. ----
---- http://acp.atari.org ----
---- ----
---- Description: ----
---- This design unit provides the DDR controller of the 'Firebee'----
---- computer. It is optimized for the use of an Altera Cyclone ----
---- FPGA (EP3C40F484). This IP-Core is based on the first edi- ----
---- tion of the Firebee configware originally provided by Fredi ----
---- Aschwanden and Wolfgang Förster. This release is in compa- ----
---- rision to the first edition completely written in VHDL. ----
---- ----
---- Author(s): ----
---- - Wolfgang Foerster, wf@experiment-s.de; wf@inventronik.de ----
---- K ----
----------------------------------------------------------------------
---- ----
---- Copyright (C) 2012 Fredi Aschwanden, Wolfgang Förster ----
---- ----
---- This source file is free software; you can redistribute it ----
---- AND/OR modify it under the terms of the GNU General Public ----
---- License as published by the Free Software Foundation; either ----
---- version 2 of the License, OR (at your option) any later ----
---- version. ----
---- ----
---- This program is distributed in the hope that it will be ----
---- useful, but WITHOUT ANY WARRANTY; WITHout even the implied ----
---- warranty of MERCHANTABILITY OR FITNESS FOR A PARTICULAR ----
---- PURPOSE. See the GNU General Public License for more ----
---- details. ----
---- ----
---- You should have received a copy of the GNU General Public ----
---- License along WITH this program; IF not, write to the Free ----
---- Software Foundation, Inc., 51 Franklin Street, Fifth Floor, ----
---- Boston, MA 02110-1301, USA. ----
---- ----
----------------------------------------------------------------------
--
-- Revision History
--
-- Revision 2K12B 20120801 WF
-- Initial Release of the second edition.
LIBRARY IEEE;
USE IEEE.std_logic_1164.ALL;
USE IEEE.numeric_std.ALL;
ENTITY DDR_CTRL IS
PORT(
clk_main : IN STD_LOGIC;
ddr_sync_66m : IN STD_LOGIC;
fb_adr : IN STD_LOGIC_VECTOR (31 DOWNTO 0);
fb_cs1_n : IN STD_LOGIC;
fb_oe_n : IN STD_LOGIC;
fb_size0 : IN STD_LOGIC;
fb_size1 : IN STD_LOGIC;
fb_ale : IN STD_LOGIC;
fb_wr_n : IN STD_LOGIC;
fifo_clr : IN STD_LOGIC;
video_control_register : IN STD_LOGIC_VECTOR (15 DOWNTO 0);
blitter_adr : IN STD_LOGIC_VECTOR (31 DOWNTO 0);
blitter_sig : IN STD_LOGIC;
blitter_wr : IN STD_LOGIC;
ddrclk0 : IN STD_LOGIC;
clk_33m : IN STD_LOGIC;
fifo_mw : IN UNSIGNED (8 DOWNTO 0);
va : OUT STD_LOGIC_VECTOR (12 DOWNTO 0); -- video Adress bus at the DDR chips
vwe_n : OUT STD_LOGIC; -- video memory write enable
vras_n : OUT STD_LOGIC; -- video memory RAS
vcs_n : OUT STD_LOGIC; -- video memory chip SELECT
vcke : OUT STD_LOGIC; -- video memory clock enable
vcas_n : OUT STD_LOGIC; -- video memory CAS
fb_le : OUT STD_LOGIC_VECTOR (3 DOWNTO 0);
fb_vdoe : OUT STD_LOGIC_VECTOR (3 DOWNTO 0);
sr_fifo_wre : OUT STD_LOGIC;
sr_ddr_fb : OUT STD_LOGIC;
sr_ddr_wr : OUT STD_LOGIC;
sr_ddrwr_d_sel : OUT STD_LOGIC;
sr_vdmp : OUT STD_LOGIC_VECTOR (7 DOWNTO 0);
video_ddr_ta : OUT STD_LOGIC;
sr_blitter_dack : OUT STD_LOGIC;
ba : OUT STD_LOGIC_VECTOR (1 DOWNTO 0);
ddrwr_d_sel1 : OUT STD_LOGIC;
vdm_sel : OUT STD_LOGIC_VECTOR (3 DOWNTO 0);
data_in : IN STD_LOGIC_VECTOR (31 DOWNTO 0);
data_out : OUT STD_LOGIC_VECTOR (31 DOWNTO 16);
data_en_h : OUT STD_LOGIC;
data_en_l : OUT STD_LOGIC
);
END ENTITY DDR_CTRL;
ARCHITECTURE BEHAVIOUR of DDR_CTRL IS
-- fifo watermark:
CONSTANT FIFO_LWM : INTEGER := 0; -- low water mark
CONSTANT FIFO_MWM : INTEGER := 200; -- medium water mark
CONSTANT FIFO_HWM : INTEGER := 500; -- high water mark
-- constants for bits in video_control_register
CONSTANT VRCR_VCKE : INTEGER := 0;
CONSTANT VRCR_REFRESH_ON : INTEGER := 2;
CONSTANT VRCR_CONFIG_ON : INTEGER := 3;
CONSTANT VRCR_VCS : INTEGER := 1;
--
CONSTANT VRCR_FIFO_ON : INTEGER := 24;
CONSTANT VRCR_BORDER_ON : INTEGER := 25;
TYPE access_width_t IS (long_access, word_access, byte_access);
TYPE ddr_access_t IS (ddr_access_cpu, ddr_access_fifo, ddr_access_blitter, ddr_access_none);
TYPE fb_regddr_t IS (fr_wait, fr_s0, fr_s1, fr_s2, fr_s3);
TYPE ddr_sm_t IS (ds_t1, ds_t2a, ds_t2b, ds_t3, ds_n5, ds_n6, ds_n7, ds_n8, -- Start (normal 8 cycles total = 60ns).
ds_c2, ds_c3, dc_c4, ds_c5, ds_c6, ds_c7, -- Configuration.
ds_t4r, ds_t5r, -- Read ddr_access_cpu OR ddr_access_blitter.
ds_t4w, ds_t5w, ds_t6w, ds_t7w, ds_t8w, ds_t9w, -- Write ddr_access_cpu OR ddr_access_blitter.
ds_t4f, ds_t5f, ds_t6f, ds_t7f, ds_t8f, ds_t9f, ds_t10f, -- Read ddr_access_fifo.
ds_cb6, ds_cb8, -- Close ddr_access_fifo bank.
ds_r2, ds_r3, ds_r4, ds_r5, ds_r6); -- Refresh: 10 x 7.5ns = 75ns.
SIGNAL access_width : access_width_t;
SIGNAL fb_regddr : fb_regddr_t;
SIGNAL fb_regddr_next : fb_regddr_t;
SIGNAL ddr_access : ddr_access_t;
SIGNAL ddr_state : ddr_sm_t;
SIGNAL ddr_next_state : ddr_sm_t;
SIGNAL byte_sel : STD_LOGIC_VECTOR (3 DOWNTO 0);
SIGNAL sr_fifo_wre_i : STD_LOGIC;
SIGNAL vcas : STD_LOGIC;
SIGNAL vras : STD_LOGIC;
SIGNAL vwe : STD_LOGIC;
SIGNAL mcs : STD_LOGIC_VECTOR (1 DOWNTO 0);
SIGNAL bus_cyc : STD_LOGIC;
SIGNAL bus_cyc_end : STD_LOGIC;
SIGNAL blitter_req : STD_LOGIC;
SIGNAL blitter_row_adr : STD_LOGIC_VECTOR (12 DOWNTO 0);
SIGNAL blitter_ba : STD_LOGIC_VECTOR (1 DOWNTO 0);
SIGNAL blitter_col_adr : STD_LOGIC_VECTOR (9 DOWNTO 0);
SIGNAL cpu_ddr_sync : STD_LOGIC;
SIGNAL cpu_row_adr : STD_LOGIC_VECTOR (12 DOWNTO 0);
SIGNAL cpu_ba : STD_LOGIC_VECTOR (1 DOWNTO 0);
SIGNAL cpu_col_adr : STD_LOGIC_VECTOR (9 DOWNTO 0);
SIGNAL cpu_req : STD_LOGIC;
SIGNAL ddr_sel : STD_LOGIC;
SIGNAL ddr_cs : STD_LOGIC;
SIGNAL ddr_config : STD_LOGIC;
SIGNAL fifo_req : STD_LOGIC;
SIGNAL fifo_row_adr : STD_LOGIC_VECTOR (12 DOWNTO 0);
SIGNAL fifo_ba : STD_LOGIC_VECTOR (1 DOWNTO 0);
SIGNAL fifo_col_adr : UNSIGNED(9 DOWNTO 0);
SIGNAL fifo_active : STD_LOGIC;
SIGNAL fifo_clr_sync : STD_LOGIC;
SIGNAL vdm_sel_i : STD_LOGIC_VECTOR (3 DOWNTO 0);
SIGNAL clear_fifo_cnt : STD_LOGIC;
SIGNAL stop : STD_LOGIC;
SIGNAL fifo_bank_ok : STD_LOGIC;
SIGNAL ddr_refresh_cnt : UNSIGNED(10 DOWNTO 0) := "00000000000";
SIGNAL ddr_refresh_req : STD_LOGIC;
SIGNAL ddr_refresh_sig : UNSIGNED(3 DOWNTO 0);
SIGNAL need_refresh : STD_LOGIC;
SIGNAL video_base_l_d : STD_LOGIC_VECTOR (7 DOWNTO 0);
SIGNAL video_base_l : STD_LOGIC;
SIGNAL video_base_m_d : STD_LOGIC_VECTOR (7 DOWNTO 0);
SIGNAL video_base_m : STD_LOGIC;
SIGNAL video_base_h_d : STD_LOGIC_VECTOR (7 DOWNTO 0);
SIGNAL video_base_h : STD_LOGIC;
SIGNAL video_base_x_d : STD_LOGIC_VECTOR (2 DOWNTO 0);
SIGNAL video_adr_cnt : UNSIGNED(22 DOWNTO 0);
SIGNAL video_cnt_l : STD_LOGIC;
SIGNAL video_cnt_m : STD_LOGIC;
SIGNAL video_cnt_h : STD_LOGIC;
SIGNAL video_base_adr : STD_LOGIC_VECTOR (22 DOWNTO 0);
SIGNAL video_act_adr : STD_LOGIC_VECTOR (26 DOWNTO 0);
SIGNAL fb_adr_i : STD_LOGIC_VECTOR (32 DOWNTO 0);
SIGNAL va_s : STD_LOGIC_VECTOR (12 DOWNTO 0);
SIGNAL va_p : STD_LOGIC_VECTOR (12 DOWNTO 0);
SIGNAL ba_s : STD_LOGIC_VECTOR (1 DOWNTO 0) ;
SIGNAL ba_p : STD_LOGIC_VECTOR (1 DOWNTO 0);
SIGNAL tsiz : STD_LOGIC_VECTOR (1 DOWNTO 0);
BEGIN
tsiz <= fb_size1 & fb_size0;
WITH tsiz SELECT
access_width <= long_access WHEN "11",
word_access WHEN "00",
byte_access WHEN OTHERS;
-- Byte selectors:
byte_sel(0) <= '1' WHEN access_width = long_access OR access_width = word_access ELSE
'1' WHEN fb_adr(1 DOWNTO 0) = "00" ELSE '0'; -- Byte 0.
byte_sel(1) <= '1' WHEN access_width = long_access OR access_width = word_access ELSE
'1' WHEN access_width = byte_access AND fb_adr(1) = '0' ELSE -- High word_access.
'1' WHEN fb_adr(1 DOWNTO 0) = "01" ELSE '0'; -- Byte 1.
byte_sel(2) <= '1' WHEN access_width = long_access OR access_width = word_access ELSE
'1' WHEN fb_adr(1 DOWNTO 0) = "10" ELSE '0'; -- Byte 2.
byte_sel(3) <= '1' WHEN access_width = long_access OR access_width = word_access ELSE
'1' WHEN access_width = byte_access AND fb_adr(1) = '1' ELSE -- Low word_access.
'1' WHEN fb_adr(1 DOWNTO 0) = "11" ELSE '0'; -- Byte 3.
---------------------------------------------------------------------------------------------------------------------------------------------------------------
------------------------------------ ddr_access_cpu READ (REG DDR => ddr_access_cpu) AND WRITE (ddr_access_cpu => REG DDR) ---------------------------------------------------------------------
fbctrl_reg : PROCESS
BEGIN
WAIT UNTIL RISING_EDGE(clk_33m);
fb_regddr <= fb_regddr_next;
END PROCESS FBCTRL_REG;
fbctrl_dec : PROCESS(fb_regddr, bus_cyc, ddr_sel, access_width, fb_wr_n, ddr_cs)
BEGIN
CASE fb_regddr IS
WHEN fr_wait =>
IF bus_cyc = '1' THEN
fb_regddr_next <= fr_s0;
ELSIF ddr_sel = '1' AND access_width = long_access AND fb_wr_n = '0' THEN
fb_regddr_next <= fr_s0;
ELSE
fb_regddr_next <= fr_wait;
END IF;
WHEN fr_s0 =>
IF ddr_cs = '1' AND access_width = long_access THEN
fb_regddr_next <= fr_s1;
ELSE
fb_regddr_next <= fr_wait;
END IF;
WHEN fr_s1 =>
IF ddr_cs = '1' THEN
fb_regddr_next <= fr_s2;
ELSE
fb_regddr_next <= fr_wait;
END IF;
WHEN fr_s2 =>
IF ddr_cs = '1' AND bus_cyc = '0' AND access_width = long_access AND fb_wr_n = '0' THEN -- wait during long_access word_access access if needed
fb_regddr_next <= fr_s2;
ELSIF ddr_cs = '1' THEN
fb_regddr_next <= fr_s3;
ELSE
fb_regddr_next <= fr_wait;
END IF;
WHEN fr_s3 =>
fb_regddr_next <= fr_wait;
END CASE;
END PROCESS FBCTRL_DEC;
-- Coldfire ddr_access_cpu access:
fb_le(0) <= NOT fb_wr_n WHEN fb_regddr = fr_wait ELSE
NOT fb_wr_n WHEN fb_regddr = fr_s0 AND ddr_cs = '1' ELSE '0';
fb_le(1) <= NOT fb_wr_n WHEN fb_regddr = fr_s1 AND ddr_cs = '1' ELSE '0';
fb_le(2) <= NOT fb_wr_n WHEN fb_regddr = fr_s2 AND ddr_cs = '1' ELSE '0';
fb_le(3) <= NOT fb_wr_n WHEN fb_regddr = fr_s3 AND ddr_cs = '1' ELSE '0';
-- video data access:
video_ddr_ta <= '1' WHEN fb_regddr = fr_s0 AND ddr_cs = '1' ELSE
'1' WHEN fb_regddr = fr_s1 AND ddr_cs = '1' ELSE
'1' WHEN fb_regddr = fr_s2 AND fb_regddr_next = fr_s3 ELSE
'1' WHEN fb_regddr = fr_s3 AND ddr_cs = '1' ELSE '0';
-- fb_vdoe # VIDEO_OE.
-- Write access for video data:
fb_vdoe(0) <= '1' WHEN fb_regddr = fr_s0 AND ddr_cs = '1' AND fb_oe_n = '0' AND ddr_config = '0' AND access_width = long_access ELSE
'1' WHEN fb_regddr = fr_s0 AND ddr_cs = '1' AND fb_oe_n = '0' AND ddr_config = '0' AND access_width /= long_access AND clk_33m = '0' ELSE '0';
fb_vdoe(1) <= '1' WHEN fb_regddr = fr_s1 AND ddr_cs = '1' AND fb_oe_n = '0' AND ddr_config = '0' ELSE '0';
fb_vdoe(2) <= '1' WHEN fb_regddr = fr_s2 AND ddr_cs = '1' AND fb_oe_n = '0' AND ddr_config = '0' ELSE '0';
fb_vdoe(3) <= '1' WHEN fb_regddr = fr_s3 AND ddr_cs = '1' AND fb_oe_n = '0' AND ddr_config = '0' AND clk_33m = '0' ELSE '0';
bus_cyc_end <= '1' WHEN fb_regddr = fr_s0 AND ddr_cs = '1' AND access_width /= long_access ELSE
'1' WHEN fb_regddr = fr_s3 AND ddr_cs = '1' ELSE '0';
---------------------------------------------------------------------------------------------------------------------------------------------------------------
------------------------------------------------------ DDR State Machine --------------------------------------------------------------------------------------
ddr_state_reg: PROCESS
BEGIN
WAIT UNTIL RISING_EDGE(ddrclk0);
ddr_state <= ddr_next_state;
END PROCESS ddr_state_reg;
ddr_state_dec: PROCESS(ddr_state, ddr_refresh_req, cpu_ddr_sync, ddr_config, fb_wr_n, ddr_access, blitter_wr, fifo_req, fifo_bank_ok,
fifo_mw, cpu_req, video_adr_cnt, ddr_sel, tsiz, data_in, fifo_ba, ddr_refresh_sig)
BEGIN
CASE ddr_state IS
WHEN ds_t1 =>
IF ddr_refresh_req = '1' THEN
ddr_next_state <= ds_r2;
ELSIF cpu_ddr_sync = '1' AND ddr_config = '1' THEN -- Synchronous start.
ddr_next_state <= ds_c2;
ELSIF cpu_ddr_sync = '1' AND cpu_req = '1' THEN -- Synchronous start.
ddr_next_state <= ds_t2b;
ELSIF cpu_ddr_sync = '1' THEN
ddr_next_state <= ds_t2a;
ELSE
ddr_next_state <= ds_t1; -- Synchronize.
END IF;
WHEN ds_t2a => -- Fast access, IN this CASE page IS always NOT ok.
ddr_next_state <= ds_t3;
WHEN ds_t2b =>
ddr_next_state <= ds_t3;
WHEN ds_t3 =>
IF ddr_access = ddr_access_cpu AND fb_wr_n = '0' THEN
ddr_next_state <= ds_t4w;
ELSIF ddr_access = ddr_access_blitter AND blitter_wr = '1' THEN
ddr_next_state <= ds_t4w;
ELSIF ddr_access = ddr_access_cpu THEN -- ddr_access_cpu?
ddr_next_state <= ds_t4r;
ELSIF ddr_access = ddr_access_fifo THEN -- ddr_access_fifo?
ddr_next_state <= ds_t4f;
ELSIF ddr_access = ddr_access_blitter THEN
ddr_next_state <= ds_t4r;
ELSE
ddr_next_state <= ds_n8;
END IF;
-- Read:
WHEN ds_t4r =>
ddr_next_state <= ds_t5r;
WHEN ds_t5r =>
IF fifo_req = '1' AND fifo_bank_ok = '1' THEN -- Insert ddr_access_fifo read, WHEN bank ok.
ddr_next_state <= ds_t6f;
ELSE
ddr_next_state <= ds_cb6;
END IF;
-- Write:
WHEN ds_t4w =>
ddr_next_state <= ds_t5w;
WHEN ds_t5w =>
ddr_next_state <= ds_t6w;
WHEN ds_t6w =>
ddr_next_state <= ds_t7w;
WHEN ds_t7w =>
ddr_next_state <= ds_t8w;
WHEN ds_t8w =>
ddr_next_state <= ds_t9w;
WHEN ds_t9w =>
IF fifo_req = '1' AND fifo_bank_ok = '1' THEN
ddr_next_state <= ds_t6f;
ELSE
ddr_next_state <= ds_cb6;
END IF;
-- ddr_access_fifo read:
WHEN ds_t4f =>
ddr_next_state <= ds_t5f;
WHEN ds_t5f =>
IF fifo_req = '1' THEN
ddr_next_state <= ds_t6f;
ELSE
ddr_next_state <= ds_cb6; -- Leave open.
END IF;
WHEN ds_t6f =>
ddr_next_state <= ds_t7f;
WHEN ds_t7f =>
IF cpu_req = '1' AND fifo_mw > FIFO_LWM THEN
ddr_next_state <= ds_cb8; -- Close bank.
ELSIF fifo_req = '1' AND video_adr_cnt(7 DOWNTO 0) = x"FF" THEN -- New page?
ddr_next_state <= ds_cb8; -- Close bank.
ELSIF fifo_req = '1' THEN
ddr_next_state <= ds_t8f;
ELSE
ddr_next_state <= ds_cb8; -- Close bank.
END IF;
WHEN ds_t8f =>
IF fifo_mw < FIFO_LWM THEN -- Emergency?
ddr_next_state <= ds_t5f; -- Yes!
ELSE
ddr_next_state <= ds_t9f;
END IF;
WHEN ds_t9f =>
IF fifo_req = '1' AND video_adr_cnt(7 DOWNTO 0) = x"FF" THEN -- New page?
ddr_next_state <= ds_cb6; -- Close bank.
ELSIF fifo_req = '1' THEN
ddr_next_state <= ds_t10f;
ELSE
ddr_next_state <= ds_cb6; -- Close bank.
END IF;
WHEN ds_t10f =>
IF ddr_sel = '1' AND (fb_wr_n = '1' OR tsiz /= "11") AND data_in(13 DOWNTO 12) /= fifo_ba THEN
ddr_next_state <= ds_t3;
ELSE
ddr_next_state <= ds_t7f;
END IF;
-- Configuration cycles:
WHEN ds_c2 =>
ddr_next_state <= ds_c3;
WHEN ds_c3 =>
ddr_next_state <= dc_c4;
WHEN dc_c4 =>
IF cpu_req = '1' THEN
ddr_next_state <= ds_c5;
ELSE
ddr_next_state <= ds_t1;
END IF;
WHEN ds_c5 =>
ddr_next_state <= ds_c6;
WHEN ds_c6 =>
ddr_next_state <= ds_c7;
WHEN ds_c7 =>
ddr_next_state <= ds_n8;
-- Close ddr_access_fifo bank.
WHEN ds_cb6 =>
ddr_next_state <= ds_n7;
WHEN ds_cb8 =>
ddr_next_state <= ds_t1;
-- Refresh 70ns = ten cycles.
WHEN ds_r2 =>
IF ddr_refresh_sig = x"9" THEN -- One cycle delay to close all banks.
ddr_next_state <= ds_r4;
ELSE
ddr_next_state <= ds_r3;
END IF;
WHEN ds_r3 =>
ddr_next_state <= ds_r4;
WHEN ds_r4 =>
ddr_next_state <= ds_r5;
WHEN ds_r5 =>
ddr_next_state <= ds_r6;
WHEN ds_r6 =>
ddr_next_state <= ds_n5;
-- Loop:
WHEN ds_n5 =>
ddr_next_state <= ds_n6;
WHEN ds_n6 =>
ddr_next_state <= ds_n7;
WHEN ds_n7 =>
ddr_next_state <= ds_n8;
WHEN ds_n8 =>
ddr_next_state <= ds_t1;
END CASE;
END PROCESS ddr_state_dec;
p_clk0 : PROCESS
BEGIN
WAIT UNTIL RISING_EDGE(ddrclk0);
-- Default assignments;
ddr_access <= ddr_access_none;
sr_fifo_wre_i <= '0';
sr_vdmp <= x"00";
sr_ddr_wr <= '0';
sr_ddrwr_d_sel <= '0';
mcs <= mcs(0) & clk_33m; -- sync on clk_33m
blitter_req <= blitter_sig AND NOT
video_control_register(VRCR_CONFIG_ON) AND
video_control_register(VRCR_VCKE) AND
video_control_register(VRCR_VCS);
fifo_clr_sync <= fifo_clr;
clear_fifo_cnt <= fifo_clr_sync OR NOT fifo_active;
stop <= fifo_clr_sync OR clear_fifo_cnt;
IF fifo_mw < fifo_mwm THEN
fifo_req <= '1';
ELSIF fifo_mw < FIFO_HWM AND fifo_req = '1' THEN
fifo_req <= '1';
ELSIF fifo_active = '1' AND
clear_fifo_cnt = '0' AND
stop = '0' AND
ddr_config = '0' AND
video_control_register(VRCR_VCKE) = '1' AND
video_control_register(VRCR_VCS) = '1' THEN
fifo_req <= '1';
ELSE
fifo_req <= '1';
END IF;
IF clear_fifo_cnt = '1' THEN
video_adr_cnt <= UNSIGNED(video_base_adr);
ELSIF sr_fifo_wre_i = '1' THEN
video_adr_cnt <= video_adr_cnt + 1;
END IF;
IF mcs = "10" AND video_control_register(VRCR_VCKE) = '1' AND video_control_register(VRCR_VCS) = '1' THEN
cpu_ddr_sync <= '1';
ELSE
cpu_ddr_sync <= '0';
END IF;
IF ddr_refresh_sig /= x"0" AND video_control_register(VRCR_REFRESH_ON) = '1' AND ddr_config = '0' AND need_refresh = '1' THEN
ddr_refresh_req <= '1';
ELSE
ddr_refresh_req <= '0';
END IF;
IF ddr_refresh_cnt = 0 AND clk_33m = '0' THEN
need_refresh <= '1';
ELSE
need_refresh <= '0';
END IF;
IF need_refresh = '1' AND video_control_register(VRCR_REFRESH_ON) = '1' AND ddr_config = '0' THEN
ddr_refresh_sig <= x"9";
ELSIF ddr_state = ds_r6 AND video_control_register(VRCR_REFRESH_ON) = '1' AND ddr_config = '0' THEN
ddr_refresh_sig <= ddr_refresh_sig - 1;
ELSE
ddr_refresh_sig <= x"0";
END IF;
IF bus_cyc_end = '1' THEN
bus_cyc <= '0';
ELSIF ddr_state = ds_t1 AND cpu_ddr_sync = '1' AND cpu_req = '1' THEN
bus_cyc <= '1';
ELSIF ddr_state = ds_t2a AND ddr_sel = '1' AND fb_wr_n = '0' THEN
bus_cyc <= '1';
ELSIF ddr_state = ds_t2a AND ddr_sel = '1' AND access_width /= long_access THEN
bus_cyc <= '1';
ELSIF ddr_state = ds_t2b THEN
bus_cyc <= '1';
ELSIF ddr_state = ds_t10f AND fb_wr_n = '0' AND data_in(13 DOWNTO 12) = fifo_ba THEN
bus_cyc <= '1';
ELSIF ddr_state = ds_t10f AND access_width /= long_access AND data_in(13 DOWNTO 12) = fifo_ba THEN
bus_cyc <= '1';
ELSIF ddr_state = ds_c3 THEN
bus_cyc <= cpu_req;
END IF;
IF ddr_state = ds_t1 AND cpu_ddr_sync = '1' AND cpu_req = '1' THEN
va_s <= cpu_row_adr;
ba_s <= cpu_ba;
ddr_access <= ddr_access_cpu;
ELSIF ddr_state = ds_t1 AND cpu_ddr_sync = '1' AND fifo_req = '1' THEN
va_p <= fifo_row_adr;
ba_p <= fifo_ba;
ddr_access <= ddr_access_fifo;
ELSIF ddr_state = ds_t1 AND cpu_ddr_sync = '1' AND blitter_req = '0' THEN
va_p <= blitter_row_adr;
ba_p <= blitter_ba;
ddr_access <= ddr_access_blitter;
ELSIF ddr_state = ds_t2a AND ddr_sel = '1' AND fb_wr_n = '0' THEN
va_s(10) <= '1';
ddr_access <= ddr_access_cpu;
ELSIF ddr_state = ds_t2a AND ddr_sel = '1' AND access_width /= long_access THEN
va_s(10) <= '1';
ddr_access <= ddr_access_cpu;
ELSIF ddr_state = ds_t2a THEN
-- ?? mfro
va_s(10) <= NOT (fifo_active AND fifo_req);
ddr_access <= ddr_access_fifo;
fifo_bank_ok <= fifo_active AND fifo_req;
IF ddr_access = ddr_access_blitter AND blitter_req = '1' THEN
ddr_access <= ddr_access_blitter;
END IF;
-- ?? mfro BLITTER_AC <= BLITTER_ACTIVE AND blitter_req;
ELSIF ddr_state = ds_t2b THEN
fifo_bank_ok <= '0';
ELSIF ddr_state = ds_t3 THEN
va_s(10) <= va_s(10);
IF (fb_wr_n = '0' AND ddr_access = ddr_access_cpu) OR (blitter_wr = '1' AND ddr_access = ddr_access_blitter) THEN
va_s(9 DOWNTO 0) <= cpu_col_adr;
ba_s <= cpu_ba;
ELSIF fifo_active = '1' THEN
va_s(9 DOWNTO 0) <= STD_LOGIC_VECTOR (fifo_col_adr);
ba_s <= fifo_ba;
ELSIF ddr_access = ddr_access_blitter THEN
va_s(9 DOWNTO 0) <= blitter_col_adr;
ba_s <= blitter_ba;
END IF;
ELSIF ddr_state = ds_t4r THEN
-- mfro change next two statements
IF ddr_access = ddr_access_cpu THEN
sr_ddr_fb <= '1';
ELSIF ddr_access = ddr_access_blitter THEN
sr_blitter_dack <= '1';
END IF;
ELSIF ddr_state = ds_t5r AND fifo_req = '1' AND fifo_bank_ok = '1' THEN
va_s(10) <= '0';
va_s(9 DOWNTO 0) <= STD_LOGIC_VECTOR (fifo_col_adr);
ba_s <= fifo_ba;
ELSIF ddr_state = ds_t5r THEN
va_s(10) <= '1';
ELSIF ddr_state = ds_t4w THEN
va_s(10) <= va_s(10);
-- mfro changed next IF
IF ddr_access = ddr_access_blitter THEN
sr_blitter_dack <= '1';
END IF;
ELSIF ddr_state = ds_t5w THEN
va_s(10) <= va_s(10);
IF ddr_access = ddr_access_cpu THEN
va_s(9 DOWNTO 0) <= cpu_col_adr;
ba_s <= cpu_ba;
ELSIF ddr_access = ddr_access_blitter THEN
va_s(9 DOWNTO 0) <= blitter_col_adr;
ba_s <= blitter_ba;
END IF;
IF ddr_access = ddr_access_blitter AND access_width = long_access THEN
sr_vdmp <= byte_sel & x"F";
ELSIF ddr_access = ddr_access_blitter THEN
sr_vdmp <= byte_sel & x"0";
ELSE
sr_vdmp <= byte_sel & x"0";
END IF;
ELSIF ddr_state = ds_t6w THEN
sr_ddr_wr <= '1';
sr_ddrwr_d_sel <= '1';
IF ddr_access = ddr_access_blitter OR access_width = long_access THEN
sr_vdmp <= x"FF";
ELSE
sr_vdmp <= x"00";
END IF;
ELSIF ddr_state = ds_t7w THEN
sr_ddr_wr <= '1';
sr_ddrwr_d_sel <= '1';
ELSIF ddr_state = ds_t9w AND fifo_req = '1' AND fifo_bank_ok = '1' THEN
va_s(10) <= '0';
va_s(9 DOWNTO 0) <= STD_LOGIC_VECTOR (fifo_col_adr);
ba_s <= fifo_ba;
ELSIF ddr_state = ds_t9w THEN
va_s(10) <= '0';
ELSIF ddr_state = ds_t4f THEN
sr_fifo_wre_i <= '1';
ELSIF ddr_state = ds_t5f AND fifo_req = '1' AND video_adr_cnt(7 DOWNTO 0) = x"FF" THEN
va_s(10) <= '1';
ELSIF ddr_state = ds_t5f AND fifo_req = '1' THEN
va_s(10) <= '0';
va_s(9 DOWNTO 0) <= STD_LOGIC_VECTOR (fifo_col_adr + "100");
ba_s <= fifo_ba;
ELSIF ddr_state = ds_t5f THEN
va_s(10) <= '0';
ELSIF ddr_state = ds_t6f THEN
sr_fifo_wre_i <= '1';
ELSIF ddr_state = ds_t7f AND cpu_req = '1' AND fifo_mw > FIFO_LWM THEN
va_s(10) <= '1';
ELSIF ddr_state = ds_t7f AND fifo_req = '1' AND video_adr_cnt(7 DOWNTO 0) = x"FF" THEN
va_s(10) <= '1';
ELSIF ddr_state = ds_t7f AND fifo_req = '1' THEN
va_s(10) <= '0';
va_s(9 DOWNTO 0) <= STD_LOGIC_VECTOR (fifo_col_adr + "100");
ba_s <= fifo_ba;
ELSIF ddr_state = ds_t7f THEN
va_s(10) <= '1';
ELSIF ddr_state = ds_t9f AND fifo_req = '1' AND video_adr_cnt(7 DOWNTO 0) = x"FF" THEN
va_s(10) <= '1';
ELSIF ddr_state = ds_t9f AND fifo_req = '1' THEN
va_p(10) <= '0';
va_p(9 DOWNTO 0) <= STD_LOGIC_VECTOR (fifo_col_adr + "100");
ba_p <= fifo_ba;
ELSIF ddr_state = ds_t9f THEN
va_s(10) <= '1';
ELSIF ddr_state = ds_t10f AND fb_wr_n = '0' AND data_in(13 DOWNTO 12) = fifo_ba THEN
va_s(10) <= '1';
ddr_access <= ddr_access_cpu;
ELSIF ddr_state = ds_t10f AND access_width /= long_access AND data_in(13 DOWNTO 12) = fifo_ba THEN
va_s(10) <= '1';
ddr_access <= ddr_access_cpu;
ELSIF ddr_state = ds_t10f THEN
sr_fifo_wre_i <= '1';
ELSIF ddr_state = ds_c6 THEN
va_s <= data_in(12 DOWNTO 0);
ba_s <= data_in(14 DOWNTO 13);
ELSIF ddr_state = ds_cb6 THEN
fifo_bank_ok <= '0';
ELSIF ddr_state = ds_cb8 THEN
fifo_bank_ok <= '0';
ELSIF ddr_state = ds_r2 THEN
fifo_bank_ok <= '0';
ELSE
END IF;
END PROCESS p_clk0;
ddr_sel <= '1' WHEN fb_ale = '1' AND data_in(31 DOWNTO 30) = "01" ELSE '0';
p_ddr_cs: PROCESS
BEGIN
WAIT UNTIL RISING_EDGE(clk_33m);
IF fb_ale = '1' THEN
ddr_cs <= ddr_sel;
END IF;
END PROCESS p_ddr_cs;
p_cpu_req: PROCESS
BEGIN
WAIT UNTIL RISING_EDGE(ddr_sync_66m);
IF ddr_sel = '1' AND fb_wr_n = '1' AND ddr_config = '0' THEN
cpu_req <= '1';
ELSIF ddr_sel = '1' AND access_width /= long_access AND ddr_config = '0' THEN -- Start when not config and not longword access.
cpu_req <= '1';
ELSIF ddr_sel = '1' AND ddr_config = '1' THEN -- Config, start immediately.
cpu_req <= '1';
ELSIF fb_regddr = fr_s1 AND fb_wr_n = '0' THEN -- Longword write later.
cpu_req <= '1';
ELSIF fb_regddr /= fr_s1 AND fb_regddr /= fr_s3 AND bus_cyc_end = '0' AND bus_cyc = '0' THEN -- Halt, bus cycle in progress or ready.
cpu_req <= '0';
END IF;
END PROCESS p_cpu_req;
p_refresh : PROCESS
-- Refresh: Always 8 at a time every 7.8us.
-- 7.8us x 8 = 62.4us = 2059 -> 2048 @ 33MHz.
BEGIN
WAIT UNTIL RISING_EDGE(clk_33m);
ddr_refresh_cnt <= ddr_refresh_cnt + 1; -- Count from 0 to 2047
END PROCESS p_refresh;
sr_fifo_wre <= sr_fifo_wre_i;
va <= data_in(26 DOWNTO 14) WHEN ddr_state = ds_t2a AND ddr_sel = '1' AND fb_wr_n = '0' ELSE
data_in(26 DOWNTO 14) WHEN ddr_state = ds_t2a AND ddr_sel = '1' AND (fb_size0 = '0' OR fb_size1= '0') ELSE
va_p WHEN ddr_state = ds_t2a ELSE
data_in(26 DOWNTO 14) WHEN ddr_state = ds_t10f AND fb_wr_n = '0' AND data_in(13 DOWNTO 12) = fifo_ba ELSE
data_in(26 DOWNTO 14) WHEN ddr_state = ds_t10f AND (fb_size0 = '0' OR fb_size1= '0') AND data_in(13 DOWNTO 12) = fifo_ba ELSE
va_p WHEN ddr_state = ds_t10f ELSE
"0010000000000" WHEN ddr_state = ds_r2 AND ddr_refresh_sig = x"9" ELSE va_s;
ba <= data_in(13 DOWNTO 12) WHEN ddr_state = ds_t2a AND ddr_sel = '1' AND fb_wr_n = '0' ELSE
data_in(13 DOWNTO 12) WHEN ddr_state = ds_t2a AND ddr_sel = '1' AND (fb_size0 = '0' OR fb_size1= '0') ELSE
ba_p WHEN ddr_state = ds_t2a ELSE
data_in(13 DOWNTO 12) WHEN ddr_state = ds_t10f AND fb_wr_n = '0' AND data_in(13 DOWNTO 12) = fifo_ba ELSE
data_in(13 DOWNTO 12) WHEN ddr_state = ds_t10f AND (fb_size0 = '0' OR fb_size1= '0') AND data_in(13 DOWNTO 12) = fifo_ba ELSE
ba_p WHEN ddr_state = ds_t10f ELSE ba_s;
vras <= '1' WHEN ddr_state = ds_t2a AND ddr_sel = '1' AND fb_wr_n = '0' ELSE
'1' WHEN ddr_state = ds_t2a AND ddr_sel = '1' AND (fb_size0 = '0' OR fb_size1= '0') ELSE
'1' WHEN ddr_state = ds_t2a AND ddr_access = ddr_access_fifo AND fifo_req = '1' ELSE
'1' WHEN ddr_state = ds_t2a AND ddr_access = ddr_access_blitter AND blitter_req = '1' ELSE
'1' WHEN ddr_state = ds_t2b ELSE
'1' WHEN ddr_state = ds_t10f AND fb_wr_n = '0' AND data_in(13 DOWNTO 12) = fifo_ba ELSE
'1' WHEN ddr_state = ds_t10f AND (fb_size0 = '0' OR fb_size1= '0') AND data_in(13 DOWNTO 12) = fifo_ba ELSE
data_in(18) AND NOT fb_wr_n AND NOT fb_size0 AND NOT fb_size1 WHEN ddr_state = ds_c7 ELSE
'1' WHEN ddr_state = ds_cb6 ELSE
'1' WHEN ddr_state = ds_cb8 ELSE
'1' WHEN ddr_state = ds_r2 ELSE '0';
vcas <= '1' WHEN ddr_state = ds_t4r ELSE
'1' WHEN ddr_state = ds_t6w ELSE
'1' WHEN ddr_state = ds_t4f ELSE
'1' WHEN ddr_state = ds_t6f ELSE
'1' WHEN ddr_state = ds_t8f ELSE
'1' WHEN ddr_state = ds_t10f AND vras = '0' ELSE
data_in(17) AND NOT fb_wr_n AND NOT fb_size0 AND NOT fb_size1 WHEN ddr_state = ds_c7 ELSE
'1' WHEN ddr_state = ds_r2 AND ddr_refresh_sig /= x"9" ELSE '0';
vwe <= '1' WHEN ddr_state = ds_t6w ELSE
data_in(16) AND NOT fb_wr_n AND NOT fb_size0 AND NOT fb_size1 WHEN ddr_state = ds_c7 ELSE
'1' WHEN ddr_state = ds_cb6 ELSE
'1' WHEN ddr_state = ds_cb8 ELSE
'1' WHEN ddr_state = ds_r2 AND ddr_refresh_sig = x"9" ELSE '0';
-- DDR controller:
-- VIDEO RAM CONTROL REGISTER (IS IN VIDEO_MUX_CTR)
-- $F0000400: BIT 0: vcke; 1: NOT nVCS ;2:REFRESH ON , (0=ddr_access_fifo AND CNT CLEAR);
-- 3: CONFIG; 8: fifo_active;
vcs_n <= NOT(video_control_register(VRCR_REFRESH_ON));
ddr_config <= video_control_register(3);
fifo_active <= video_control_register(8);
cpu_row_adr <= fb_adr(26 DOWNTO 14);
cpu_ba <= fb_adr(13 DOWNTO 12);
cpu_col_adr <= fb_adr(11 DOWNTO 2);
vras_n <= NOT vras;
vcas_n <= NOT vcas;
vwe_n <= NOT vwe;
ddrwr_d_sel1 <= '1' WHEN ddr_access = ddr_access_blitter ELSE '0';
blitter_row_adr <= blitter_adr(26 DOWNTO 14);
blitter_ba <= blitter_adr(13 DOWNTO 12);
blitter_col_adr <= blitter_adr(11 DOWNTO 2);
fifo_row_adr <= STD_LOGIC_VECTOR (video_adr_cnt(22 DOWNTO 10));
fifo_ba <= STD_LOGIC_VECTOR (video_adr_cnt(9 DOWNTO 8));
fifo_col_adr <= video_adr_cnt(7 DOWNTO 0) & "00";
video_base_adr(22 DOWNTO 20) <= video_base_x_d;
video_base_adr(19 DOWNTO 12) <= video_base_h_d;
video_base_adr(11 DOWNTO 4) <= video_base_m_d;
video_base_adr(3 DOWNTO 0) <= video_base_l_d(7 DOWNTO 4);
vdm_sel <= vdm_sel_i;
vdm_sel_i <= video_base_l_d(3 DOWNTO 0);
-- Current video address:
video_act_adr(26 DOWNTO 4) <= STD_LOGIC_VECTOR (video_adr_cnt - fifo_mw);
video_act_adr(3 DOWNTO 0) <= vdm_sel_i;
p_video_regs : PROCESS
-- Video registers.
BEGIN
WAIT UNTIL RISING_EDGE(clk_33m);
IF video_base_l = '1' AND fb_wr_n = '0' AND byte_sel(1) = '1' THEN
video_base_l_d <= data_in(23 DOWNTO 16); -- 16 byte boarders.
END IF;
IF video_base_m = '1' AND fb_wr_n = '0' AND byte_sel(3) = '1' THEN
video_base_m_d <= data_in(23 DOWNTO 16);
END IF;
IF video_base_h = '1' AND fb_wr_n = '0' AND byte_sel(1) = '1' THEN
video_base_h_d <= data_in(23 DOWNTO 16);
END IF;
IF video_base_h = '1' AND fb_wr_n = '0' AND byte_sel(0) = '1' THEN
video_base_x_d <= data_in(26 DOWNTO 24);
END IF;
END PROCESS p_video_regs;
fb_adr_i <= fb_adr & '0';
video_base_l <= '1' WHEN fb_cs1_n = '0' AND fb_adr_i(15 DOWNTO 0) = x"820D" ELSE '0'; -- x"FF820D".
video_base_m <= '1' WHEN fb_cs1_n = '0' AND fb_adr_i(15 DOWNTO 0) = x"8204" ELSE '0'; -- x"FF8203".
video_base_h <= '1' WHEN fb_cs1_n = '0' AND fb_adr_i(15 DOWNTO 0) = x"8202" ELSE '0'; -- x"FF8201".
video_cnt_l <= '1' WHEN fb_cs1_n = '0' AND fb_adr_i(15 DOWNTO 0) = x"8208" ELSE '0'; -- x"FF8209".
video_cnt_m <= '1' WHEN fb_cs1_n = '0' AND fb_adr_i(15 DOWNTO 0) = x"8206" ELSE '0'; -- x"FF8207".
video_cnt_h <= '1' WHEN fb_cs1_n = '0' AND fb_adr_i(15 DOWNTO 0) = x"8204" ELSE '0'; -- x"FF8205".
data_out(31 DOWNTO 24) <= "00000" & video_base_x_d WHEN video_base_h = '1' ELSE
"00000" & video_act_adr(26 DOWNTO 24) WHEN video_cnt_h = '1' ELSE (OTHERS => '0');
data_en_h <= (video_base_h OR video_cnt_h) AND NOT fb_oe_n;
data_out(23 DOWNTO 16) <= video_base_l_d WHEN video_base_l = '1' ELSE
video_base_m_d WHEN video_base_m = '1' ELSE
video_base_h_d WHEN video_base_h = '1' ELSE
video_act_adr(7 DOWNTO 0) WHEN video_cnt_l = '1' ELSE
video_act_adr(15 DOWNTO 8) WHEN video_cnt_m = '1' ELSE
video_act_adr(23 DOWNTO 16) WHEN video_cnt_h = '1' ELSE (OTHERS => '0');
data_en_l <= (video_base_l OR video_base_m OR video_base_h OR video_cnt_l OR video_cnt_m OR video_cnt_h) AND NOT fb_oe_n;
END ARCHITECTURE BEHAVIOUR;
-- va : Video DDR address multiplexed
-- va_p : latched va, wenn FIFO_AC, BLITTER_AC
-- va_s : latch for default va
-- ba : Video DDR bank address multiplexed
-- ba_p : latched ba, wenn FIFO_AC, BLITTER_AC
-- ba_s : latch for default ba
--
--FB_SIZE ersetzen.