@ -398,6 +398,17 @@ begin
-- major opcode 31, lots of things
-- major opcode 31, lots of things
v.decode := decode_op_31_array(to_integer(unsigned(f_in.insn(10 downto 1))));
v.decode := decode_op_31_array(to_integer(unsigned(f_in.insn(10 downto 1))));
-- Work out ispr1/ispr2 independent of v.decode since they seem to be critical path
sprn := decode_spr_num(f_in.insn);
v.ispr1 := fast_spr_num(sprn);
elsif majorop = "010000" then
-- CTR may be needed as input to bc
v.decode := major_decode_rom_array(to_integer(majorop));
if f_in.insn(23) = '0' then
v.ispr1 := fast_spr_num(SPR_CTR);
end if;
elsif majorop = "010011" then
elsif majorop = "010011" then
if decode_op_19_valid(to_integer(unsigned(f_in.insn(10 downto 1)))) = '0' then
if decode_op_19_valid(to_integer(unsigned(f_in.insn(10 downto 1)))) = '0' then
report "op 19 illegal subcode";
report "op 19 illegal subcode";
@ -408,6 +419,27 @@ begin
report "op 19 sub " & to_hstring(op_19_bits);
report "op 19 sub " & to_hstring(op_19_bits);
end if;
end if;
-- Work out ispr1/ispr2 independent of v.decode since they seem to be critical path
if f_in.insn(2) = '0' then
-- Could be OP_BCREG: bclr, bcctr, bctar
-- Branch uses CTR as condition when BO(2) is 0. This is
-- also used to indicate that CTR is modified (they go
-- together).
if f_in.insn(23) = '0' then
v.ispr1 := fast_spr_num(SPR_CTR);
end if;
-- TODO: Add TAR
if f_in.insn(10) = '0' then
v.ispr2 := fast_spr_num(SPR_LR);
else
v.ispr2 := fast_spr_num(SPR_CTR);
end if;
else
-- Could be OP_RFID
v.ispr1 := fast_spr_num(SPR_SRR0);
v.ispr2 := fast_spr_num(SPR_SRR1);
end if;
elsif majorop = "011110" then
elsif majorop = "011110" then
v.decode := decode_op_30_array(to_integer(unsigned(f_in.insn(4 downto 1))));
v.decode := decode_op_30_array(to_integer(unsigned(f_in.insn(4 downto 1))));
@ -423,30 +455,11 @@ begin
else
else
v.decode := major_decode_rom_array(to_integer(majorop));
v.decode := major_decode_rom_array(to_integer(majorop));
end if;
-- Set ISPR1/ISPR2 when needed
if v.decode.insn_type = OP_BC or v.decode.insn_type = OP_BCREG then
-- Branch uses CTR as condition when BO(2) is 0. This is
-- also used to indicate that CTR is modified (they go
-- together).
--
if f_in.insn(23) = '0' then
v.ispr1 := fast_spr_num(SPR_CTR);
end if;
end if;
-- Branch source register is an SPR
if v.decode.insn_type = OP_MFSPR or v.decode.insn_type = OP_MTSPR then
if v.decode.insn_type = OP_BCREG then
-- TODO: Add TAR
if f_in.insn(10) = '0' then
v.ispr2 := fast_spr_num(SPR_LR);
else
v.ispr2 := fast_spr_num(SPR_CTR);
end if;
end if;
elsif v.decode.insn_type = OP_MFSPR or v.decode.insn_type = OP_MTSPR then
sprn := decode_spr_num(f_in.insn);
sprn := decode_spr_num(f_in.insn);
v.ispr1 := fast_spr_num(sprn);
-- Make slow SPRs single issue
-- Make slow SPRs single issue
if is_fast_spr(v.ispr1) = '0' then
if is_fast_spr(v.ispr1) = '0' then
v.decode.sgl_pipe := '1';
v.decode.sgl_pipe := '1';
@ -457,10 +470,6 @@ begin
when others =>
when others =>
end case;
end case;
end if;
end if;
elsif v.decode.insn_type = OP_RFID then
report "PPC RFID";
v.ispr1 := fast_spr_num(SPR_SRR0);
v.ispr2 := fast_spr_num(SPR_SRR1);
end if;
end if;
if flush_in = '1' then
if flush_in = '1' then