forked from cores/microwatt
You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
58 lines
1.1 KiB
VHDL
58 lines
1.1 KiB
VHDL
library ieee;
|
|
use ieee.std_logic_1164.all;
|
|
use ieee.numeric_std.all;
|
|
|
|
library work;
|
|
use work.common.all;
|
|
use work.crhelpers.all;
|
|
use work.ppc_fx_insns.all;
|
|
|
|
-- 2 cycle ALU
|
|
-- We handle rc form instructions here
|
|
|
|
entity execute2 is
|
|
port (
|
|
clk : in std_ulogic;
|
|
|
|
e_in : in Execute1ToExecute2Type;
|
|
e_out : out Execute2ToWritebackType
|
|
);
|
|
end execute2;
|
|
|
|
architecture behave of execute2 is
|
|
signal r, rin : Execute2ToWritebackType;
|
|
begin
|
|
execute2_0: process(clk)
|
|
begin
|
|
if rising_edge(clk) then
|
|
r <= rin;
|
|
end if;
|
|
end process;
|
|
|
|
execute2_1: process(all)
|
|
variable v : Execute2ToWritebackType;
|
|
begin
|
|
v := rin;
|
|
|
|
v.valid := e_in.valid;
|
|
v.write_enable := e_in.write_enable;
|
|
v.write_reg := e_in.write_reg;
|
|
v.write_data := e_in.write_data;
|
|
v.write_cr_enable := e_in.write_cr_enable;
|
|
v.write_cr_mask := e_in.write_cr_mask;
|
|
v.write_cr_data := e_in.write_cr_data;
|
|
|
|
if e_in.valid = '1' and e_in.rc = '1' then
|
|
v.write_cr_enable := '1';
|
|
v.write_cr_mask := num_to_fxm(0);
|
|
v.write_cr_data := ppc_cmpi('1', e_in.write_data, x"0000") & x"0000000";
|
|
end if;
|
|
|
|
-- Update registers
|
|
rin <= v;
|
|
|
|
-- Update outputs
|
|
e_out <= r;
|
|
end process;
|
|
end;
|