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Reformat loadstore2

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Signed-off-by: Anton Blanchard <anton@linux.ibm.com>
pull/65/head
Anton Blanchard 5 years ago committed by Anton Blanchard
parent e1a71e4545
commit 6e442e07a5
1 changed files with 147 additions and 147 deletions
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loadstore2.vhdl
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@ -11,157 +11,157 @@ use work.wishbone_types.all;
-- In this cycle we read or write any data and do sign extension and update if required. -- In this cycle we read or write any data and do sign extension and update if required.


entity loadstore2 is entity loadstore2 is
port ( port (
clk : in std_ulogic; clk : in std_ulogic;


l_in : in Loadstore1ToLoadstore2Type; l_in : in Loadstore1ToLoadstore2Type;
w_out : out Loadstore2ToWritebackType; w_out : out Loadstore2ToWritebackType;


m_in : in wishbone_slave_out; m_in : in wishbone_slave_out;
m_out : out wishbone_master_out m_out : out wishbone_master_out
); );
end loadstore2; end loadstore2;


architecture behave of loadstore2 is architecture behave of loadstore2 is
signal l_saved : Loadstore1ToLoadstore2Type; signal l_saved : Loadstore1ToLoadstore2Type;
signal w_tmp : Loadstore2ToWritebackType; signal w_tmp : Loadstore2ToWritebackType;
signal m_tmp : wishbone_master_out; signal m_tmp : wishbone_master_out;


type state_t is (IDLE, WAITING_FOR_READ_ACK, WAITING_FOR_WRITE_ACK); type state_t is (IDLE, WAITING_FOR_READ_ACK, WAITING_FOR_WRITE_ACK);
signal state : state_t := IDLE; signal state : state_t := IDLE;


function length_to_sel(length : in std_logic_vector(3 downto 0)) return std_ulogic_vector is function length_to_sel(length : in std_logic_vector(3 downto 0)) return std_ulogic_vector is
begin begin
case length is case length is
when "0001" => when "0001" =>
return "00000001"; return "00000001";
when "0010" => when "0010" =>
return "00000011"; return "00000011";
when "0100" => when "0100" =>
return "00001111"; return "00001111";
when "1000" => when "1000" =>
return "11111111"; return "11111111";
when others => when others =>
return "00000000"; return "00000000";
end case; end case;
end function length_to_sel; end function length_to_sel;


function wishbone_data_shift(address : in std_ulogic_vector(63 downto 0)) return natural is function wishbone_data_shift(address : in std_ulogic_vector(63 downto 0)) return natural is
begin begin
return to_integer(unsigned(address(2 downto 0))) * 8; return to_integer(unsigned(address(2 downto 0))) * 8;
end function wishbone_data_shift; end function wishbone_data_shift;


function wishbone_data_sel(size : in std_logic_vector(3 downto 0); address : in std_logic_vector(63 downto 0)) return std_ulogic_vector is function wishbone_data_sel(size : in std_logic_vector(3 downto 0); address : in std_logic_vector(63 downto 0)) return std_ulogic_vector is
begin begin
return std_ulogic_vector(shift_left(unsigned(length_to_sel(size)), to_integer(unsigned(address(2 downto 0))))); return std_ulogic_vector(shift_left(unsigned(length_to_sel(size)), to_integer(unsigned(address(2 downto 0)))));
end function wishbone_data_sel; end function wishbone_data_sel;
begin begin
w_out <= w_tmp; w_out <= w_tmp;
m_out <= m_tmp; m_out <= m_tmp;


loadstore2_0: process(clk) loadstore2_0: process(clk)
variable tmp : std_ulogic_vector(63 downto 0); variable tmp : std_ulogic_vector(63 downto 0);
variable data : std_ulogic_vector(63 downto 0); variable data : std_ulogic_vector(63 downto 0);
variable sign_extend_byte_reverse : std_ulogic_vector(1 downto 0); variable sign_extend_byte_reverse : std_ulogic_vector(1 downto 0);
begin begin
if rising_edge(clk) then if rising_edge(clk) then
tmp := (others => '0'); tmp := (others => '0');
data := (others => '0'); data := (others => '0');


w_tmp <= Loadstore2ToWritebackInit; w_tmp <= Loadstore2ToWritebackInit;


l_saved <= l_saved; l_saved <= l_saved;


case_0: case state is case_0: case state is
when IDLE => when IDLE =>
if l_in.valid = '1' then if l_in.valid = '1' then
m_tmp <= wishbone_master_out_init; m_tmp <= wishbone_master_out_init;


m_tmp.sel <= wishbone_data_sel(l_in.length, l_in.addr); m_tmp.sel <= wishbone_data_sel(l_in.length, l_in.addr);
m_tmp.adr <= l_in.addr(63 downto 3) & "000"; m_tmp.adr <= l_in.addr(63 downto 3) & "000";
m_tmp.cyc <= '1'; m_tmp.cyc <= '1';
m_tmp.stb <= '1'; m_tmp.stb <= '1';


l_saved <= l_in; l_saved <= l_in;


if l_in.load = '1' then if l_in.load = '1' then
m_tmp.we <= '0'; m_tmp.we <= '0';


-- Load with update instructions write two GPR destinations. -- Load with update instructions write two GPR destinations.
-- We don't want the expense of two write ports, so make it -- We don't want the expense of two write ports, so make it
-- single in the pipeline and write back the update GPR now -- single in the pipeline and write back the update GPR now
-- and the load once we get the data back. We'll have to -- and the load once we get the data back. We'll have to
-- revisit this when loads can take exceptions. -- revisit this when loads can take exceptions.
if l_in.update = '1' then if l_in.update = '1' then
w_tmp.write_enable <= '1'; w_tmp.write_enable <= '1';
w_tmp.write_reg <= l_in.update_reg; w_tmp.write_reg <= l_in.update_reg;
w_tmp.write_data <= l_in.addr; w_tmp.write_data <= l_in.addr;
end if; end if;


state <= WAITING_FOR_READ_ACK; state <= WAITING_FOR_READ_ACK;
else else
m_tmp.we <= '1'; m_tmp.we <= '1';


data := l_in.data; data := l_in.data;
m_tmp.dat <= std_logic_vector(shift_left(unsigned(data), wishbone_data_shift(l_in.addr))); m_tmp.dat <= std_logic_vector(shift_left(unsigned(data), wishbone_data_shift(l_in.addr)));


assert l_in.sign_extend = '0' report "sign extension doesn't make sense for stores" severity failure; assert l_in.sign_extend = '0' report "sign extension doesn't make sense for stores" severity failure;


state <= WAITING_FOR_WRITE_ACK; state <= WAITING_FOR_WRITE_ACK;
end if; end if;
end if; end if;


when WAITING_FOR_READ_ACK => when WAITING_FOR_READ_ACK =>
if m_in.ack = '1' then if m_in.ack = '1' then
tmp := std_logic_vector(shift_right(unsigned(m_in.dat), wishbone_data_shift(l_saved.addr))); tmp := std_logic_vector(shift_right(unsigned(m_in.dat), wishbone_data_shift(l_saved.addr)));
case to_integer(unsigned(l_saved.length)) is case to_integer(unsigned(l_saved.length)) is
when 0 => when 0 =>
when 1 => when 1 =>
data(7 downto 0) := tmp(7 downto 0); data(7 downto 0) := tmp(7 downto 0);
when 2 => when 2 =>
data(15 downto 0) := tmp(15 downto 0); data(15 downto 0) := tmp(15 downto 0);
when 4 => when 4 =>
data(31 downto 0) := tmp(31 downto 0); data(31 downto 0) := tmp(31 downto 0);
when 8 => when 8 =>
data(63 downto 0) := tmp(63 downto 0); data(63 downto 0) := tmp(63 downto 0);
when others => when others =>
assert false report "invalid length" severity failure; assert false report "invalid length" severity failure;
end case; end case;


sign_extend_byte_reverse := l_saved.sign_extend & l_saved.byte_reverse; sign_extend_byte_reverse := l_saved.sign_extend & l_saved.byte_reverse;


case sign_extend_byte_reverse is case sign_extend_byte_reverse is
when "10" => when "10" =>
data := sign_extend(data, to_integer(unsigned(l_saved.length))); data := sign_extend(data, to_integer(unsigned(l_saved.length)));
when "01" => when "01" =>
data := byte_reverse(data, to_integer(unsigned(l_saved.length))); data := byte_reverse(data, to_integer(unsigned(l_saved.length)));
when others => when others =>
end case; end case;


w_tmp.write_data <= data; w_tmp.write_data <= data;


-- write data to register file -- write data to register file
w_tmp.valid <= '1'; w_tmp.valid <= '1';
w_tmp.write_enable <= '1'; w_tmp.write_enable <= '1';
w_tmp.write_reg <= l_saved.write_reg; w_tmp.write_reg <= l_saved.write_reg;


m_tmp <= wishbone_master_out_init; m_tmp <= wishbone_master_out_init;
state <= IDLE; state <= IDLE;
end if; end if;


when WAITING_FOR_WRITE_ACK => when WAITING_FOR_WRITE_ACK =>
if m_in.ack = '1' then if m_in.ack = '1' then
w_tmp.valid <= '1'; w_tmp.valid <= '1';
if l_saved.update = '1' then if l_saved.update = '1' then
w_tmp.write_enable <= '1'; w_tmp.write_enable <= '1';
w_tmp.write_reg <= l_saved.update_reg; w_tmp.write_reg <= l_saved.update_reg;
w_tmp.write_data <= l_saved.addr; w_tmp.write_data <= l_saved.addr;
end if; end if;


m_tmp <= wishbone_master_out_init; m_tmp <= wishbone_master_out_init;
state <= IDLE; state <= IDLE;
end if; end if;
end case; end case;
end if; end if;
end process; end process;
end; end;

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