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.
100 lines
3.3 KiB
VHDL
100 lines
3.3 KiB
VHDL
library ieee;
|
|
use ieee.std_logic_1164.all;
|
|
use ieee.numeric_std.all;
|
|
|
|
library work;
|
|
use work.common.all;
|
|
|
|
entity writeback is
|
|
port (
|
|
clk : in std_ulogic;
|
|
|
|
e_in : in Execute2ToWritebackType;
|
|
l_in : in Loadstore2ToWritebackType;
|
|
m_in : in MultiplyToWritebackType;
|
|
d_in : in DividerToWritebackType;
|
|
|
|
w_out : out WritebackToRegisterFileType;
|
|
c_out : out WritebackToCrFileType;
|
|
|
|
complete_out : out std_ulogic
|
|
);
|
|
end entity writeback;
|
|
|
|
architecture behaviour of writeback is
|
|
begin
|
|
writeback_1: process(all)
|
|
variable x : std_ulogic_vector(0 downto 0);
|
|
variable y : std_ulogic_vector(0 downto 0);
|
|
variable z : std_ulogic_vector(0 downto 0);
|
|
variable w : std_ulogic_vector(0 downto 0);
|
|
begin
|
|
x := "" & e_in.valid;
|
|
y := "" & l_in.valid;
|
|
z := "" & m_in.valid;
|
|
w := "" & d_in.valid;
|
|
assert (to_integer(unsigned(x)) + to_integer(unsigned(y)) + to_integer(unsigned(z)) + to_integer(unsigned(w))) <= 1 severity failure;
|
|
|
|
x := "" & e_in.write_enable;
|
|
y := "" & l_in.write_enable;
|
|
z := "" & m_in.write_reg_enable;
|
|
w := "" & d_in.write_reg_enable;
|
|
assert (to_integer(unsigned(x)) + to_integer(unsigned(y)) + to_integer(unsigned(z)) + to_integer(unsigned(w))) <= 1 severity failure;
|
|
|
|
x := "" & e_in.write_cr_enable;
|
|
y := "" & m_in.write_cr_enable;
|
|
z := "" & d_in.write_cr_enable;
|
|
assert (to_integer(unsigned(x)) + to_integer(unsigned(y)) + to_integer(unsigned(z))) <= 1 severity failure;
|
|
|
|
w_out <= WritebackToRegisterFileInit;
|
|
c_out <= WritebackToCrFileInit;
|
|
|
|
complete_out <= '0';
|
|
if e_in.valid = '1' or l_in.valid = '1' or m_in.valid = '1' or d_in.valid = '1' then
|
|
complete_out <= '1';
|
|
end if;
|
|
|
|
if e_in.write_enable = '1' then
|
|
w_out.write_reg <= e_in.write_reg;
|
|
w_out.write_data <= e_in.write_data;
|
|
w_out.write_enable <= '1';
|
|
end if;
|
|
|
|
if e_in.write_cr_enable = '1' then
|
|
c_out.write_cr_enable <= '1';
|
|
c_out.write_cr_mask <= e_in.write_cr_mask;
|
|
c_out.write_cr_data <= e_in.write_cr_data;
|
|
end if;
|
|
|
|
if l_in.write_enable = '1' then
|
|
w_out.write_reg <= l_in.write_reg;
|
|
w_out.write_data <= l_in.write_data;
|
|
w_out.write_enable <= '1';
|
|
end if;
|
|
|
|
if m_in.write_reg_enable = '1' then
|
|
w_out.write_enable <= '1';
|
|
w_out.write_reg <= m_in.write_reg_nr;
|
|
w_out.write_data <= m_in.write_reg_data;
|
|
end if;
|
|
|
|
if m_in.write_cr_enable = '1' then
|
|
c_out.write_cr_enable <= '1';
|
|
c_out.write_cr_mask <= m_in.write_cr_mask;
|
|
c_out.write_cr_data <= m_in.write_cr_data;
|
|
end if;
|
|
|
|
if d_in.write_reg_enable = '1' then
|
|
w_out.write_enable <= '1';
|
|
w_out.write_reg <= d_in.write_reg_nr;
|
|
w_out.write_data <= d_in.write_reg_data;
|
|
end if;
|
|
|
|
if d_in.write_cr_enable = '1' then
|
|
c_out.write_cr_enable <= '1';
|
|
c_out.write_cr_mask <= d_in.write_cr_mask;
|
|
c_out.write_cr_data <= d_in.write_cr_data;
|
|
end if;
|
|
end process;
|
|
end;
|