- reworked FIFOs

- use synchronous resets

git-svn-id: http://moon:8086/svn/vhdl/trunk@1090 cc03376c-175c-47c8-b038-4cd826a8556b
This commit is contained in:
2015-05-16 15:05:04 +00:00
parent bbd2673d42
commit deefbcffb3
5 changed files with 145 additions and 120 deletions
+1 -1
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@@ -3,7 +3,7 @@
vlib work vlib work
vcom -explicit -93 "../src/fifo_ctrl_pkg.vhd" vcom -explicit -93 "../src/fifo_ctrl_pkg.vhd"
vcom -explicit -93 "../src/gray_counter.vhd" vcom -explicit -93 "../src/gray_counter.vhd"
vcom -explicit -93 "../../rams/dpram_1w1r2c_ro_sim.vhd" vcom -explicit -93 "../../rams/dpram_1w1r2c_ra_sim.vhd"
vcom -explicit -93 "../src/fifo_async_ctrl.vhd" vcom -explicit -93 "../src/fifo_async_ctrl.vhd"
vcom -explicit -93 "../src/fifo_async.vhd" vcom -explicit -93 "../src/fifo_async.vhd"
vcom -explicit -93 "../src/tb_fifo_async.vhd" vcom -explicit -93 "../src/tb_fifo_async.vhd"
+1 -1
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@@ -2,7 +2,7 @@
## ##
vlib work vlib work
vcom -explicit -93 "../src/fifo_ctrl_pkg.vhd" vcom -explicit -93 "../src/fifo_ctrl_pkg.vhd"
vcom -explicit -93 "../../rams/dpram_1w1r2c_ro_sim.vhd" vcom -explicit -93 "../../rams/dpram_1w1r2c_ra_sim.vhd"
vcom -explicit -93 "../src/fifo_sync_ctrl.vhd" vcom -explicit -93 "../src/fifo_sync_ctrl.vhd"
vcom -explicit -93 "../src/fifo_sync.vhd" vcom -explicit -93 "../src/fifo_sync.vhd"
vcom -explicit -93 "../src/tb_fifo_sync.vhd" vcom -explicit -93 "../src/tb_fifo_sync.vhd"
+60 -35
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@@ -71,6 +71,7 @@ architecture Behavioral of fifo_async_ctrl is
signal pre_empty, pre_full : std_logic; signal pre_empty, pre_full : std_logic;
signal full, empty : std_logic; signal full, empty : std_logic;
signal rst_w, rst_r : std_logic;
-- synthesis translate_off -- synthesis translate_off
signal diffw : signed (addr_width downto 0); signal diffw : signed (addr_width downto 0);
@@ -85,25 +86,45 @@ begin
fifo_empty <= empty; fifo_empty <= empty;
fifo_pre_full <= pre_full; fifo_pre_full <= pre_full;
fifo_pre_empty <= pre_empty; fifo_pre_empty <= pre_empty;
sync_reset_w:
process(clk_w)
begin
if rising_edge(clk_w) then
rst_w <= rst;
end if;
end process;
sync_reset_r:
process(clk_r)
begin
if rising_edge(clk_r) then
rst_r <= rst;
end if;
end process;
proc_write_inhibit: proc_write_inhibit:
process(rst, clk_w) process(clk_w)
begin begin
if rst = '1' then if rising_edge(clk_w) then
full <= '0'; if rst_w = '1' then
elsif rising_edge(clk_w) then full <= '0';
full <= pre_full; else
full <= pre_full;
end if;
end if; end if;
end process; end process;
proc_read_inhibit: proc_read_inhibit:
process(rst, clk_r) process(clk_r)
begin begin
if rst = '1' then if rising_edge(clk_r) then
empty <= '1'; if rst_r = '1' then
elsif rising_edge(clk_r) then empty <= '1';
empty <= pre_empty; else
end if; empty <= pre_empty;
end if;
end if;
end process; end process;
proc_sync_grptr: proc_sync_grptr:
@@ -171,42 +192,46 @@ proc_ptr_awptr:
end process; end process;
proc_status_almost_full: proc_status_almost_full:
process(rst, clk_w) process(clk_w)
variable diff : unsigned (addr_width downto 0); variable diff : unsigned (addr_width downto 0);
begin begin
-- synthesis translate_off -- synthesis translate_off
diffw <= signed(diff); diffw <= signed(diff);
-- synthesis translate_on -- synthesis translate_on
if rst = '1' then if rising_edge(clk_w) then
fifo_afull <= '0'; if rst_w = '1' then
diff := (others => '0'); fifo_afull <= '0';
elsif rising_edge(clk_w) then diff := (others => '0');
if diff >= almost_full_thresh-1 then else
fifo_afull <= '1'; if diff >= almost_full_thresh-1 then
else fifo_afull <= '1';
fifo_afull <= '0'; else
end if; fifo_afull <= '0';
diff := unsigned(abs(signed(bnxt_w) - signed(bcnt2_ar))); end if;
diff := unsigned(abs(signed(bnxt_w) - signed(bcnt2_ar)));
end if;
end if; end if;
end process; end process;
proc_status_almost_empty: proc_status_almost_empty:
process(rst, clk_r) process(clk_r)
variable diff : unsigned (addr_width downto 0); variable diff : unsigned (addr_width downto 0);
begin begin
-- synthesis translate_off -- synthesis translate_off
diffr <= signed(diff); diffr <= signed(diff);
-- synthesis translate_on -- synthesis translate_on
if rst = '1' then if rising_edge(clk_r) then
fifo_aempty <= '1'; if rst_r = '1' then
diff := (others => '0'); fifo_aempty <= '1';
elsif rising_edge(clk_r) then diff := (others => '0');
if diff <= almost_empty_thresh+1 then else
fifo_aempty <= '1'; if diff <= almost_empty_thresh+1 then
else fifo_aempty <= '1';
fifo_aempty <= '0'; else
end if; fifo_aempty <= '0';
diff := unsigned(abs(signed(bcnt2_aw) - signed(bnxt_r))); end if;
diff := unsigned(abs(signed(bcnt2_aw) - signed(bnxt_r)));
end if;
end if; end if;
end process; end process;
@@ -218,7 +243,7 @@ inst_gray_counter_w : entity work.gray_counter
) )
port map port map
( (
rst => rst, rst => rst_w,
clk => clk_w, clk => clk_w,
ce => winc, ce => winc,
bcnt => bcnt_w, bcnt => bcnt_w,
@@ -235,7 +260,7 @@ inst_gray_counter_r : entity work.gray_counter
) )
port map port map
( (
rst => rst, rst => rst_r,
clk => clk_r, clk => clk_r,
ce => rinc, ce => rinc,
bcnt => bcnt_r, bcnt => bcnt_r,
+67 -63
View File
@@ -68,64 +68,74 @@ begin
proc_diff_gen: proc_diff_gen:
process(rst, clk) process(clk)
begin begin
if rst = '1' then if rising_edge(clk) then
diff <= (others => '0'); if rst = '1' then
elsif rising_edge(clk) then diff <= (others => '0');
if winc = '1' and rinc = '0' then else
diff <= diff + 1; if winc = '1' and rinc = '0' then
elsif winc = '0' and rinc = '1' then diff <= diff + 1;
diff <= diff - 1; elsif winc = '0' and rinc = '1' then
end if; diff <= diff - 1;
end if;
end if;
end if; end if;
end process; end process;
proc_status_almost_full: proc_status_almost_full:
process(rst, clk) process(clk)
begin begin
if rst = '1' then if rising_edge(clk) then
fifo_afull <= '0'; if rst = '1' then
elsif rising_edge(clk) then fifo_afull <= '0';
if diff >= almost_full_thresh-1 then else
fifo_afull <= '1'; if diff >= almost_full_thresh-1 then
else fifo_afull <= '1';
fifo_afull <= '0'; else
end if; fifo_afull <= '0';
end if;
end if;
end if; end if;
end process; end process;
proc_status_almost_empty: proc_status_almost_empty:
process(rst, clk) process(clk)
begin begin
if rst = '1' then if rising_edge(clk) then
fifo_aempty <= '1'; if rst = '1' then
elsif rising_edge(clk) then fifo_aempty <= '1';
if diff <= almost_empty_thresh+1 then else
fifo_aempty <= '1'; if diff <= almost_empty_thresh+1 then
else fifo_aempty <= '1';
fifo_aempty <= '0'; else
end if; fifo_aempty <= '0';
end if;
end if;
end if; end if;
end process; end process;
proc_full_reg: proc_full_reg:
process(rst, clk) process(clk)
begin begin
if rst = '1' then if rising_edge(clk) then
full <= '0'; if rst = '1' then
elsif rising_edge(clk) then full <= '0';
full <= pre_full; else
full <= pre_full;
end if;
end if; end if;
end process; end process;
proc_empty_reg: proc_empty_reg:
process(rst, clk) process(clk)
begin begin
if rst = '1' then if rising_edge(clk) then
empty <= '1'; if rst = '1' then
elsif rising_edge(clk) then empty <= '1';
empty <= pre_empty; else
empty <= pre_empty;
end if;
end if; end if;
end process; end process;
@@ -147,10 +157,10 @@ proc_status_w:
proc_flag_write: proc_flag_write:
process(rst, clk) process(rst, clk)
begin begin
if rst = '1' then if rising_edge(clk) then
was_write <= '0'; if rst = '1' then
elsif rising_edge(clk) then was_write <= '0';
if winc = '1' then elsif winc = '1' then
was_write <= '1'; was_write <= '1';
elsif rinc = '1' then elsif rinc = '1' then
was_write <= '0'; was_write <= '0';
@@ -158,40 +168,34 @@ proc_flag_write:
end if; end if;
end process; end process;
pW_next <= (pW + 1) when winc = '1' else pW;
ptr_w <= pW;
proc_ptr_w: proc_ptr_w:
process(rst, clk, pW, winc) process(clk)
begin begin
if rst = '1' then if rising_edge(clk) then
pW <= to_unsigned(0, addr_width); if rst = '1' then
pW_next <= to_unsigned(0, addr_width); pW <= to_unsigned(0, addr_width);
elsif rising_edge(clk) then else
if winc = '1' then
pW <= pW_next; pW <= pW_next;
end if; end if;
end if; end if;
pW_next <= pW;
if winc = '1' then
pW_next <= pW + 1;
end if;
ptr_w <= pW;
end process; end process;
pR_next <= (pR + 1) when rinc = '1' else pR;
ptr_r <= pR_next;
proc_ptr_r: proc_ptr_r:
process(rst, clk, pR_next, pR, rinc) process(clk)
begin begin
if rst = '1' then if rising_edge(clk) then
pR <= to_unsigned(0, addr_width); if rst = '1' then
pR_next <= to_unsigned(0, addr_width); pR <= to_unsigned(0, addr_width);
elsif rising_edge(clk) then else
if rinc = '1' then
pR <= pR_next; pR <= pR_next;
end if; end if;
end if; end if;
pR_next <= pR;
if rinc = '1' then
pR_next <= pR + 1;
end if;
ptr_r <= pR_next;
end process; end process;
end Behavioral; end Behavioral;
+16 -20
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@@ -60,25 +60,21 @@ begin
bcnt <= cntb; bcnt <= cntb;
gcnt <= cntg; gcnt <= cntg;
process(rst, clk, ce, cntb, nxtb) nxtg <= bin2gray(nxtb);
begin nxtb <= (cntb + 1) when ce = '1' else cntb;
if rst = '1' then
cntb <= to_unsigned(init_value, width); process(clk)
nxtb <= to_unsigned(init_value, width); begin
nxtg <= to_unsigned(init_value, width); if rising_edge(clk) then
cntg <= to_unsigned(init_value, width); if rst = '1' then
else cntb <= to_unsigned(init_value, width);
if rising_edge(clk) then cntg <= to_unsigned(init_value, width);
cntg <= nxtg; else
cntb <= nxtb; cntg <= nxtg;
end if; cntb <= nxtb;
nxtg <= bin2gray(nxtb); end if;
nxtb <= cntb; end if;
if ce = '1' then end process;
nxtb <= cntb + 1;
end if;
end if;
end process;
end Behavioral; end Behavioral;