ACK_WAIT, -- waiting for ack from dcache
LD_UPDATE, -- writing rA with computed addr on load
MMU_LOOKUP, -- waiting for MMU to look up translation
- TLBIE_WAIT -- waiting for MMU to finish doing a tlbie
+ TLBIE_WAIT, -- waiting for MMU to finish doing a tlbie
+ SPR_CMPLT -- complete a mf/tspr operation
);
type reg_stage_t is record
- busy : std_ulogic;
-- latch most of the input request
load : std_ulogic;
tlbie : std_ulogic;
dcbz : std_ulogic;
+ mfspr : std_ulogic;
addr : std_ulogic_vector(63 downto 0);
store_data : std_ulogic_vector(63 downto 0);
load_data : std_ulogic_vector(63 downto 0);
dar : std_ulogic_vector(63 downto 0);
dsisr : std_ulogic_vector(31 downto 0);
instr_fault : std_ulogic;
+ sprval : std_ulogic_vector(63 downto 0);
end record;
type byte_sel_t is array(0 to 7) of std_ulogic;
if rising_edge(clk) then
if rst = '1' then
r.state <= IDLE;
- r.busy <= '0';
else
r <= rin;
end if;
variable long_sel : std_ulogic_vector(15 downto 0);
variable byte_sel : std_ulogic_vector(7 downto 0);
variable req : std_ulogic;
- variable stall : std_ulogic;
+ variable busy : std_ulogic;
variable addr : std_ulogic_vector(63 downto 0);
variable wdata : std_ulogic_vector(63 downto 0);
variable write_enable : std_ulogic;
variable use_second : byte_sel_t;
variable trim_ctl : trim_ctl_t;
variable negative : std_ulogic;
- variable mfspr : std_ulogic;
variable sprn : std_ulogic_vector(9 downto 0);
- variable sprval : std_ulogic_vector(63 downto 0);
variable exception : std_ulogic;
variable next_addr : std_ulogic_vector(63 downto 0);
variable mmureq : std_ulogic;
begin
v := r;
req := '0';
- stall := '0';
- done := '0';
byte_sel := (others => '0');
addr := lsu_sum;
- mfspr := '0';
+ v.mfspr := '0';
mmu_mtspr := '0';
itlb_fault := '0';
sprn := std_ulogic_vector(to_unsigned(decode_spr_num(l_in.insn), 10));
- sprval := (others => '0'); -- avoid inferred latches
- exception := '0';
dsisr := (others => '0');
mmureq := '0';
-- compute (addr + 8) & ~7 for the second doubleword when unaligned
next_addr := std_ulogic_vector(unsigned(r.addr(63 downto 3)) + 1) & "000";
+ done := '0';
+ exception := '0';
case r.state is
when IDLE =>
- if l_in.valid = '1' then
- v.addr := lsu_sum;
- v.load := '0';
- v.dcbz := '0';
- v.tlbie := '0';
- v.instr_fault := '0';
- v.dwords_done := '0';
- case l_in.op is
- when OP_STORE =>
- req := '1';
- when OP_LOAD =>
- req := '1';
- v.load := '1';
- when OP_DCBZ =>
- req := '1';
- v.dcbz := '1';
- when OP_TLBIE =>
- mmureq := '1';
- stall := '1';
- v.tlbie := '1';
- v.state := TLBIE_WAIT;
- when OP_MFSPR =>
- done := '1';
- mfspr := '1';
- -- partial decode on SPR number should be adequate given
- -- the restricted set that get sent down this path
- if sprn(9) = '0' and sprn(5) = '0' then
- if sprn(0) = '0' then
- sprval := x"00000000" & r.dsisr;
- else
- sprval := r.dar;
- end if;
- else
- -- reading one of the SPRs in the MMU
- sprval := m_in.sprval;
- end if;
- when OP_MTSPR =>
- if sprn(9) = '0' and sprn(5) = '0' then
- if sprn(0) = '0' then
- v.dsisr := l_in.data(31 downto 0);
- else
- v.dar := l_in.data;
- end if;
- done := '1';
- else
- -- writing one of the SPRs in the MMU
- mmu_mtspr := '1';
- stall := '1';
- v.state := TLBIE_WAIT;
- end if;
- when OP_FETCH_FAILED =>
- -- send it to the MMU to do the radix walk
- addr := l_in.nia;
- v.addr := l_in.nia;
- v.instr_fault := '1';
- mmureq := '1';
- stall := '1';
- v.state := MMU_LOOKUP;
- when others =>
- assert false report "unknown op sent to loadstore1";
- end case;
-
- v.write_reg := l_in.write_reg;
- v.length := l_in.length;
- v.byte_reverse := l_in.byte_reverse;
- v.sign_extend := l_in.sign_extend;
- v.update := l_in.update;
- v.update_reg := l_in.update_reg;
- v.xerc := l_in.xerc;
- v.reserve := l_in.reserve;
- v.rc := l_in.rc;
- v.nc := l_in.ci;
- v.virt_mode := l_in.virt_mode;
- v.priv_mode := l_in.priv_mode;
-
- -- XXX Temporary hack. Mark the op as non-cachable if the address
- -- is the form 0xc------- for a real-mode access.
- --
- -- This will have to be replaced by a combination of implementing the
- -- proper HV CI load/store instructions and having an MMU to get the I
- -- bit otherwise.
- if lsu_sum(31 downto 28) = "1100" and l_in.virt_mode = '0' then
- v.nc := '1';
- end if;
-
- -- Do length_to_sel and work out if we are doing 2 dwords
- long_sel := xfer_data_sel(l_in.length, v.addr(2 downto 0));
- byte_sel := long_sel(7 downto 0);
- v.first_bytes := byte_sel;
- v.second_bytes := long_sel(15 downto 8);
-
- -- Do byte reversing and rotating for stores in the first cycle
- byte_offset := unsigned(lsu_sum(2 downto 0));
- brev_lenm1 := "000";
- if l_in.byte_reverse = '1' then
- brev_lenm1 := unsigned(l_in.length(2 downto 0)) - 1;
- end if;
- for i in 0 to 7 loop
- k := (to_unsigned(i, 3) xor brev_lenm1) + byte_offset;
- j := to_integer(k) * 8;
- v.store_data(j + 7 downto j) := l_in.data(i * 8 + 7 downto i * 8);
- end loop;
-
- if req = '1' then
- stall := '1';
- if long_sel(15 downto 8) = "00000000" then
- v.state := ACK_WAIT;
- else
- v.state := SECOND_REQ;
- end if;
- end if;
- end if;
when SECOND_REQ =>
addr := next_addr;
byte_sel := r.second_bytes;
req := '1';
- stall := '1';
v.state := ACK_WAIT;
when ACK_WAIT =>
- stall := '1';
if d_in.valid = '1' then
if d_in.error = '1' then
-- dcache will discard the second request if it
else
-- stores write back rA update in this cycle
do_update := r.update;
- stall := '0';
done := '1';
v.state := IDLE;
end if;
end if;
when MMU_LOOKUP =>
- stall := '1';
if r.dwords_done = '1' then
addr := next_addr;
byte_sel := r.second_bytes;
end if;
else
-- nothing to do, the icache retries automatically
- stall := '0';
done := '1';
v.state := IDLE;
end if;
end if;
when TLBIE_WAIT =>
- stall := '1';
if m_in.done = '1' then
-- tlbie is finished
- stall := '0';
done := '1';
v.state := IDLE;
end if;
v.state := IDLE;
done := '1';
+ when SPR_CMPLT =>
+ done := '1';
+ v.state := IDLE;
+
end case;
+ busy := '1';
+ if r.state = IDLE or done = '1' then
+ busy := '0';
+ end if;
+
+ -- Note that l_in.valid is gated with busy inside execute1
+ if l_in.valid = '1' then
+ v.addr := lsu_sum;
+ v.load := '0';
+ v.dcbz := '0';
+ v.tlbie := '0';
+ v.instr_fault := '0';
+ v.dwords_done := '0';
+ v.write_reg := l_in.write_reg;
+ v.length := l_in.length;
+ v.byte_reverse := l_in.byte_reverse;
+ v.sign_extend := l_in.sign_extend;
+ v.update := l_in.update;
+ v.update_reg := l_in.update_reg;
+ v.xerc := l_in.xerc;
+ v.reserve := l_in.reserve;
+ v.rc := l_in.rc;
+ v.nc := l_in.ci;
+ v.virt_mode := l_in.virt_mode;
+ v.priv_mode := l_in.priv_mode;
+
+ -- XXX Temporary hack. Mark the op as non-cachable if the address
+ -- is the form 0xc------- for a real-mode access.
+ if lsu_sum(31 downto 28) = "1100" and l_in.virt_mode = '0' then
+ v.nc := '1';
+ end if;
+
+ -- Do length_to_sel and work out if we are doing 2 dwords
+ long_sel := xfer_data_sel(l_in.length, v.addr(2 downto 0));
+ byte_sel := long_sel(7 downto 0);
+ v.first_bytes := byte_sel;
+ v.second_bytes := long_sel(15 downto 8);
+
+ -- Do byte reversing and rotating for stores in the first cycle
+ byte_offset := unsigned(lsu_sum(2 downto 0));
+ brev_lenm1 := "000";
+ if l_in.byte_reverse = '1' then
+ brev_lenm1 := unsigned(l_in.length(2 downto 0)) - 1;
+ end if;
+ for i in 0 to 7 loop
+ k := (to_unsigned(i, 3) xor brev_lenm1) + byte_offset;
+ j := to_integer(k) * 8;
+ v.store_data(j + 7 downto j) := l_in.data(i * 8 + 7 downto i * 8);
+ end loop;
+
+ case l_in.op is
+ when OP_STORE =>
+ req := '1';
+ when OP_LOAD =>
+ req := '1';
+ v.load := '1';
+ when OP_DCBZ =>
+ req := '1';
+ v.dcbz := '1';
+ when OP_TLBIE =>
+ mmureq := '1';
+ v.tlbie := '1';
+ v.state := TLBIE_WAIT;
+ when OP_MFSPR =>
+ v.mfspr := '1';
+ -- partial decode on SPR number should be adequate given
+ -- the restricted set that get sent down this path
+ if sprn(9) = '0' and sprn(5) = '0' then
+ if sprn(0) = '0' then
+ v.sprval := x"00000000" & r.dsisr;
+ else
+ v.sprval := r.dar;
+ end if;
+ else
+ -- reading one of the SPRs in the MMU
+ v.sprval := m_in.sprval;
+ end if;
+ v.state := SPR_CMPLT;
+ when OP_MTSPR =>
+ if sprn(9) = '0' and sprn(5) = '0' then
+ if sprn(0) = '0' then
+ v.dsisr := l_in.data(31 downto 0);
+ else
+ v.dar := l_in.data;
+ end if;
+ v.state := SPR_CMPLT;
+ else
+ -- writing one of the SPRs in the MMU
+ mmu_mtspr := '1';
+ v.state := TLBIE_WAIT;
+ end if;
+ when OP_FETCH_FAILED =>
+ -- send it to the MMU to do the radix walk
+ addr := l_in.nia;
+ v.addr := l_in.nia;
+ v.instr_fault := '1';
+ mmureq := '1';
+ v.state := MMU_LOOKUP;
+ when others =>
+ assert false report "unknown op sent to loadstore1";
+ end case;
+
+ if req = '1' then
+ if long_sel(15 downto 8) = "00000000" then
+ v.state := ACK_WAIT;
+ else
+ v.state := SECOND_REQ;
+ end if;
+ end if;
+ end if;
+
-- Update outputs to dcache
d_out.valid <= req;
d_out.load <= v.load;
-- Multiplex either cache data to the destination GPR or
-- the address for the rA update.
l_out.valid <= done;
- if mfspr = '1' then
+ if r.mfspr = '1' then
l_out.write_enable <= '1';
- l_out.write_reg <= l_in.write_reg;
- l_out.write_data <= sprval;
+ l_out.write_reg <= r.write_reg;
+ l_out.write_data <= r.sprval;
elsif do_update = '1' then
l_out.write_enable <= '1';
l_out.write_reg <= r.update_reg;
l_out.store_done <= d_in.store_done;
-- update exception info back to execute1
- e_out.busy <= r.busy;
+ e_out.busy <= busy;
e_out.exception <= exception;
e_out.instr_fault <= r.instr_fault;
e_out.invalid <= m_in.invalid;
end if;
end if;
- v.busy := stall;
-
-- Update registers
rin <= v;
ls1_log: process(clk)
begin
if rising_edge(clk) then
- log_data <= r.busy &
+ log_data <= e_out.busy &
e_out.exception &
l_out.valid &
m_out.valid &
projects / microwatt.git / blobdiff