Merge pull request #260 from paulusmack/misc

soc: Drive uart1_irq to 0 when we don't have UART1
pull/262/head
Anton Blanchard 4 years ago committed by GitHub
commit ebe696affc
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@ -35,9 +35,7 @@ entity fetch1 is
end entity fetch1;

architecture behaviour of fetch1 is
type stop_state_t is (RUNNING, STOPPED, RESTARTING);
type reg_internal_t is record
stop_state: stop_state_t;
mode_32bit: std_ulogic;
end record;
signal r, r_next : Fetch1ToIcacheType;
@ -70,7 +68,6 @@ begin
comb : process(all)
variable v : Fetch1ToIcacheType;
variable v_int : reg_internal_t;
variable increment : boolean;
begin
v := r;
v_int := r_int;
@ -85,7 +82,6 @@ begin
v.virt_mode := '0';
v.priv_mode := '1';
v.big_endian := '0';
v_int.stop_state := RUNNING;
v_int.mode_32bit := '0';
elsif e_in.redirect = '1' then
v.nia := e_in.redirect_nia(63 downto 2) & "00";
@ -103,49 +99,9 @@ begin
end if;
elsif stall_in = '0' then

-- For debug stop/step to work properly we need a little bit of
-- trickery here. If we just stop incrementing and send stop marks
-- when stop_in is set, then we'll increment on the cycle it clears
-- and end up never executing the instruction we were stopped on.
--
-- Avoid this along with the opposite issue when stepping (stop is
-- cleared for only one cycle) is handled by the state machine below
--
-- By default, increment addresses
increment := true;
case v_int.stop_state is
when RUNNING =>
-- If we are running and stop_in is set, then stop incrementing,
-- we are now stopped.
if stop_in = '1' then
increment := false;
v_int.stop_state := STOPPED;
end if;
when STOPPED =>
-- When stopped, never increment. If stop is cleared, go to state
-- "restarting" but still don't increment that cycle. stop_in is
-- now 0 so we'll send the NIA down without a stop mark.
increment := false;
if stop_in = '0' then
v_int.stop_state := RESTARTING;
end if;
when RESTARTING =>
-- We have just sent the NIA down, we can start incrementing again.
-- If stop_in is still not set, go back to running normally.
-- If stop_in is set again (that was a one-cycle "step"), go
-- back to "stopped" state which means we'll stop incrementing
-- on the next cycle. This ensures we increment the PC once after
-- sending one instruction without a stop mark. Since stop_in is
-- now set, the new PC will be sent with a stop mark and thus not
-- executed.
if stop_in = '0' then
v_int.stop_state := RUNNING;
else
v_int.stop_state := STOPPED;
end if;
end case;

if increment then
-- If the last NIA value went down with a stop mark, it didn't get
-- executed, and hence we shouldn't increment NIA.
if r.stop_mark = '0' then
if r_int.mode_32bit = '0' then
v.nia := std_ulogic_vector(unsigned(r.nia) + 4);
else
@ -155,7 +111,7 @@ begin
end if;
end if;

v.req := not rst;
v.req := not rst and not stop_in;
v.stop_mark := stop_in;

r_next <= v;

@ -499,7 +499,7 @@ begin
-- last cycle, and we don't want the first 32-bit chunk, then we can
-- keep the data we read last cycle and just use that.
if unsigned(i_in.nia(INSN_BITS+2-1 downto 2)) /= 0 then
use_previous <= i_in.sequential and r.hit_valid;
use_previous <= i_in.req and i_in.sequential and r.hit_valid;
else
use_previous <= '0';
end if;

@ -754,6 +754,7 @@ begin
wb_uart1_out.dat <= x"00000000";
wb_uart1_out.ack <= wb_uart1_in.cyc and wb_uart1_in.stb;
wb_uart1_out.stall <= '0';
uart1_irq <= '0';
end generate;

spiflash_gen: if HAS_SPI_FLASH generate

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