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White Rabbit core collection
Commit 12fecf86 authored by Tomasz Wlostowski's avatar Tomasz Wlostowski Committed by Maciej Lipinski
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wr_streamers: fixed timestamp wraparound detection in fixed latency mode

parent 946d409a
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Showing with 40 additions and 18 deletions
modules/wr_streamers/fixed_latency_delay.vhd
View file @ 12fecf86
......@@ -12,7 +12,9 @@ entity fixed_latency_delay is
g_data_width : integer;
g_buffer_size : integer;
g_use_ref_clock_for_data : integer;
g_clk_ref_rate : integer
g_clk_ref_rate : integer;
g_simulation : integer := 0;
g_sim_cycle_counter_range: integer := 125000000
);
port(
rst_n_i : in std_logic;
......@@ -54,9 +56,7 @@ architecture rtl of fixed_latency_delay is
type t_state is (IDLE, TS_SETUP_MATCH, TS_WAIT_MATCH, SEND);
signal State: t_state;
signal clk_data : std_logic;
signal rst_n_data : std_logic;
signal rst_n_ref : std_logic;
signal wr_full : std_logic;
constant c_datapath_width : integer := g_data_width + 2 + 28 + 1;
......@@ -175,7 +175,7 @@ begin
when TS_WAIT_MATCH =>
if delay_miss = '1' or delay_match = '1' then
if fifo_last = '1' then
if fifo_last = '1' and fifo_empty = '0' then
state <= TS_SETUP_MATCH;
else
state <= SEND;
......@@ -190,7 +190,8 @@ begin
else
state <= TS_SETUP_MATCH;
end if;
elsif fifo_empty = '1' then
state <= IDLE;
end if;
end case;
end if;
......@@ -200,7 +201,9 @@ begin
U_Compare: entity work.fixed_latency_ts_match
generic map (
g_clk_ref_rate => g_clk_ref_rate)
g_clk_ref_rate => g_clk_ref_rate,
g_sim_cycle_counter_range => g_sim_cycle_counter_range,
g_simulation => g_simulation)
port map (
clk_i => clk_ref_i,
rst_n_i => rst_n_ref,
......
modules/wr_streamers/fixed_latency_ts_match.vhd
View file @ 12fecf86
......@@ -4,7 +4,11 @@ use ieee.numeric_std.all;
entity fixed_latency_ts_match is
generic
(g_clk_ref_rate : integer);
(g_clk_ref_rate : integer;
g_simulation : integer := 0;
g_sim_cycle_counter_range : integer := 125000000
);
port
(
clk_i : in std_logic;
......@@ -32,11 +36,21 @@ end entity;
architecture rtl of fixed_latency_ts_match is
constant c_unwrap_threshold : integer := 62500000;
impure function f_cycles_counter_range return integer is
begin
if g_simulation = 1 then
return g_sim_cycle_counter_range;
else
return 125000000;
end if;
end function;
constant c_rollover_threshold_lo : integer := f_cycles_counter_range / 4;
constant c_rollover_threshold_hi : integer := f_cycles_counter_range * 3 / 4;
signal ts_adjusted : unsigned(28 downto 0);
signal target_cycles : unsigned(28 downto 0);
signal delta : signed(28 downto 0);
signal arm_d : std_logic_vector(2 downto 0);
signal armed : std_logic;
......@@ -64,6 +78,7 @@ begin
begin
if rising_edge(clk_i) then
if rst_n_i = '0' then
armed <= '0';
arm_d <= (others => '0');
miss_o <= '0';
else
......@@ -73,17 +88,19 @@ begin
match_o <= '0';
miss_o <= '0';
ts_adjusted <= resize(unsigned(ts_origin_i) + unsigned(ts_latency_i), 29);
delta <= signed('0'&ts_origin_i) + signed('0'&ts_latency_i) - signed('0'&tm_cycles_i);
end if;
if delta < -c_unwrap_threshold or delta > c_unwrap_threshold then
ts_adjusted <= ts_adjusted + 125000000;
target_cycles <= tm_cycles_scaled + 125000000;
if ts_adjusted < c_rollover_threshold_lo and tm_cycles_scaled > c_rollover_threshold_hi then
target_cycles <= tm_cycles_scaled + f_cycles_counter_range;
if arm_d(0) = '1' then
ts_adjusted <= ts_adjusted + f_cycles_counter_range;
end if;
else
target_cycles <= tm_cycles_scaled;
end if;
if (arm_d(1) = '1') then
if ts_adjusted < target_cycles then
miss_o <= '1';
......@@ -92,7 +109,7 @@ begin
end if;
end if;
if armed = '1' and ts_adjusted = target_cycles then
if armed = '1' and ts_adjusted = tm_cycles_scaled then
match_o <= '1';
armed <= '0';
else
......
modules/wr_streamers/xrx_streamer.vhd
View file @ 12fecf86
......@@ -275,7 +275,9 @@ begin -- rtl
g_data_width => g_data_width,
g_buffer_size => 32,
g_use_ref_clock_for_data => g_use_ref_clock_for_data,
g_clk_ref_rate => g_clk_ref_rate)
g_clk_ref_rate => g_clk_ref_rate,
g_sim_cycle_counter_range => g_sim_cycle_counter_range,
g_simulation => g_simulation)
port map (
rst_n_i => rst_n_i,
clk_sys_i => clk_sys_i,
......
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