from soc.decoder.power_regspec_map import regspec_decode_read
from soc.decoder.power_regspec_map import regspec_decode_write
from soc.decoder.power_decoder import create_pdecode
-from soc.decoder.power_enums import (InternalOp, CryIn, Function,
+from soc.decoder.power_enums import (MicrOp, CryIn, Function,
CRInSel, CROutSel,
LdstLen, In1Sel, In2Sel, In3Sel,
- OutSel, SPR, RC)
+ OutSel, SPR, RC, LDSTMode)
from soc.decoder.decode2execute1 import Decode2ToExecute1Type, Data
+from soc.consts import MSR
from soc.regfile.regfiles import FastRegs
+from soc.consts import TT
+from soc.config.state import CoreState
-# see traptype (and trap main_stage.py)
-
-TT_FP = 1<<0
-TT_PRIV = 1<<1
-TT_TRAP = 1<<2
-TT_ADDR = 1<<3
-TT_ILLEG = 1<<4
def decode_spr_num(spr):
return Cat(spr[5:10], spr[0:5])
"""determines if the instruction is privileged or not
"""
comb = m.d.comb
- Signal = is_priv_insn(reset_less=True)
+ is_priv_insn = Signal(reset_less=True)
with m.Switch(op):
- with m.Case(InternalOp.OP_ATTN) : comb += is_priv_insn.eq(1)
- with m.Case(InternalOp.OP_MFMSR) : comb += is_priv_insn.eq(1)
- with m.Case(InternalOp.OP_MTMSRD): comb += is_priv_insn.eq(1)
- with m.Case(InternalOp.OP_MTMSR): comb += is_priv_insn.eq(1)
- with m.Case(InternalOp.OP_RFID) : comb += is_priv_insn.eq(1)
- with m.Case(InternalOp.OP_TLBIE) : comb += is_priv_insn.eq(1)
- with m.If(op == OP_MFSPR | op == OP_MTSPR):
- with m.If(insn[20]): # field XFX.spr[-1] i think
+ with m.Case(MicrOp.OP_ATTN, MicrOp.OP_MFMSR, MicrOp.OP_MTMSRD,
+ MicrOp.OP_MTMSR, MicrOp.OP_RFID):
comb += is_priv_insn.eq(1)
+ # XXX TODO
+ #with m.Case(MicrOp.OP_TLBIE) : comb += is_priv_insn.eq(1)
+ with m.Case(MicrOp.OP_MFSPR, MicrOp.OP_MTSPR):
+ with m.If(insn[20]): # field XFX.spr[-1] i think
+ comb += is_priv_insn.eq(1)
return is_priv_insn
class SPRMap(Elaboratable):
"""SPRMap: maps POWER9 SPR numbers to internal enum values
"""
+
def __init__(self):
self.spr_i = Signal(10, reset_less=True)
self.spr_o = Signal(SPR, reset_less=True)
# decode Fast-SPR based on instruction type
op = self.dec.op
- # BC or BCREG: potential implicit register (CTR) NOTE: same in DecodeOut
- with m.If(op.internal_op == InternalOp.OP_BC):
- with m.If(~self.dec.BO[2]): # 3.0B p38 BO2=0, use CTR reg
- comb += self.fast_out.data.eq(FastRegs.CTR) # constant: CTR
- comb += self.fast_out.ok.eq(1)
- with m.Elif(op.internal_op == InternalOp.OP_BCREG):
- xo9 = self.dec.FormXL.XO[9] # 3.0B p38 top bit of XO
- xo5 = self.dec.FormXL.XO[5] # 3.0B p38
- with m.If(xo9 & ~xo5):
- comb += self.fast_out.data.eq(FastRegs.CTR) # constant: CTR
- comb += self.fast_out.ok.eq(1)
+ with m.Switch(op.internal_op):
- # MFSPR move from SPRs
- with m.If(op.internal_op == InternalOp.OP_MFSPR):
- spr = Signal(10, reset_less=True)
- comb += spr.eq(decode_spr_num(self.dec.SPR)) # from XFX
- with m.Switch(spr):
- # fast SPRs
- with m.Case(SPR.CTR.value):
+ # BC or BCREG: implicit register (CTR) NOTE: same in DecodeOut
+ with m.Case(MicrOp.OP_BC):
+ with m.If(~self.dec.BO[2]): # 3.0B p38 BO2=0, use CTR reg
+ # constant: CTR
comb += self.fast_out.data.eq(FastRegs.CTR)
comb += self.fast_out.ok.eq(1)
- with m.Case(SPR.LR.value):
- comb += self.fast_out.data.eq(FastRegs.LR)
- comb += self.fast_out.ok.eq(1)
- with m.Case(SPR.TAR.value):
- comb += self.fast_out.data.eq(FastRegs.TAR)
- comb += self.fast_out.ok.eq(1)
- with m.Case(SPR.SRR0.value):
- comb += self.fast_out.data.eq(FastRegs.SRR0)
- comb += self.fast_out.ok.eq(1)
- with m.Case(SPR.SRR1.value):
- comb += self.fast_out.data.eq(FastRegs.SRR1)
+ with m.Case(MicrOp.OP_BCREG):
+ xo9 = self.dec.FormXL.XO[9] # 3.0B p38 top bit of XO
+ xo5 = self.dec.FormXL.XO[5] # 3.0B p38
+ with m.If(xo9 & ~xo5):
+ # constant: CTR
+ comb += self.fast_out.data.eq(FastRegs.CTR)
comb += self.fast_out.ok.eq(1)
- with m.Case(SPR.XER.value):
- pass # do nothing
- # XXX TODO: map to internal SPR numbers
- # XXX TODO: dec and tb not to go through mapping.
- with m.Default():
- comb += sprmap.spr_i.eq(spr)
- comb += self.spr_out.data.eq(sprmap.spr_o)
- comb += self.spr_out.ok.eq(1)
+ # MFSPR move from SPRs
+ with m.Case(MicrOp.OP_MFSPR):
+ spr = Signal(10, reset_less=True)
+ comb += spr.eq(decode_spr_num(self.dec.SPR)) # from XFX
+ with m.Switch(spr):
+ # fast SPRs
+ with m.Case(SPR.CTR.value):
+ comb += self.fast_out.data.eq(FastRegs.CTR)
+ comb += self.fast_out.ok.eq(1)
+ with m.Case(SPR.LR.value):
+ comb += self.fast_out.data.eq(FastRegs.LR)
+ comb += self.fast_out.ok.eq(1)
+ with m.Case(SPR.TAR.value):
+ comb += self.fast_out.data.eq(FastRegs.TAR)
+ comb += self.fast_out.ok.eq(1)
+ with m.Case(SPR.SRR0.value):
+ comb += self.fast_out.data.eq(FastRegs.SRR0)
+ comb += self.fast_out.ok.eq(1)
+ with m.Case(SPR.SRR1.value):
+ comb += self.fast_out.data.eq(FastRegs.SRR1)
+ comb += self.fast_out.ok.eq(1)
+ with m.Case(SPR.XER.value):
+ pass # do nothing
+ # : map to internal SPR numbers
+ # XXX TODO: dec and tb not to go through mapping.
+ with m.Default():
+ comb += sprmap.spr_i.eq(spr)
+ comb += self.spr_out.data.eq(sprmap.spr_o)
+ comb += self.spr_out.ok.eq(1)
return m
comb += self.reg_out.data.eq(self.dec.RB)
comb += self.reg_out.ok.eq(1)
with m.Case(In2Sel.RS):
- comb += self.reg_out.data.eq(self.dec.RS) # for M-Form shiftrot
+ # for M-Form shiftrot
+ comb += self.reg_out.data.eq(self.dec.RS)
comb += self.reg_out.ok.eq(1)
- with m.Case(In2Sel.CONST_UI):
+ with m.Case(In2Sel.CONST_UI): # unsigned
comb += self.imm_out.data.eq(self.dec.UI)
comb += self.imm_out.ok.eq(1)
- with m.Case(In2Sel.CONST_SI): # TODO: sign-extend here?
- comb += self.imm_out.data.eq(
- exts(self.dec.SI, 16, 64))
+ with m.Case(In2Sel.CONST_SI): # sign-extended 16-bit
+ si = Signal(16, reset_less=True)
+ comb += si.eq(self.dec.SI)
+ comb += self.imm_out.data.eq(exts(si, 16, 64))
comb += self.imm_out.ok.eq(1)
- with m.Case(In2Sel.CONST_UI_HI):
- comb += self.imm_out.data.eq(self.dec.UI<<16)
+ with m.Case(In2Sel.CONST_SI_HI): # sign-extended 16+16=32 bit
+ si_hi = Signal(32, reset_less=True)
+ comb += si_hi.eq(self.dec.SI << 16)
+ comb += self.imm_out.data.eq(exts(si_hi, 32, 64))
comb += self.imm_out.ok.eq(1)
- with m.Case(In2Sel.CONST_SI_HI): # TODO: sign-extend here?
- comb += self.imm_out.data.eq(self.dec.SI<<16)
- comb += self.imm_out.data.eq(
- exts(self.dec.SI << 16, 32, 64))
+ with m.Case(In2Sel.CONST_UI_HI): # unsigned
+ ui = Signal(16, reset_less=True)
+ comb += ui.eq(self.dec.UI)
+ comb += self.imm_out.data.eq(ui << 16)
comb += self.imm_out.ok.eq(1)
- with m.Case(In2Sel.CONST_LI):
- comb += self.imm_out.data.eq(self.dec.LI<<2)
+ with m.Case(In2Sel.CONST_LI): # sign-extend 24+2=26 bit
+ li = Signal(26, reset_less=True)
+ comb += li.eq(self.dec.LI << 2)
+ comb += self.imm_out.data.eq(exts(li, 26, 64))
comb += self.imm_out.ok.eq(1)
- with m.Case(In2Sel.CONST_BD):
- comb += self.imm_out.data.eq(self.dec.BD<<2)
+ with m.Case(In2Sel.CONST_BD): # sign-extend (14+2)=16 bit
+ bd = Signal(16, reset_less=True)
+ comb += bd.eq(self.dec.BD << 2)
+ comb += self.imm_out.data.eq(exts(bd, 16, 64))
comb += self.imm_out.ok.eq(1)
- with m.Case(In2Sel.CONST_DS):
- comb += self.imm_out.data.eq(self.dec.DS<<2)
+ with m.Case(In2Sel.CONST_DS): # sign-extended (14+2=16) bit
+ ds = Signal(16, reset_less=True)
+ comb += ds.eq(self.dec.DS << 2)
+ comb += self.imm_out.data.eq(exts(ds, 16, 64))
comb += self.imm_out.ok.eq(1)
- with m.Case(In2Sel.CONST_M1):
- comb += self.imm_out.data.eq(~Const(0, 64)) # all 1s
+ with m.Case(In2Sel.CONST_M1): # signed (-1)
+ comb += self.imm_out.data.eq(~Const(0, 64)) # all 1s
comb += self.imm_out.ok.eq(1)
- with m.Case(In2Sel.CONST_SH):
+ with m.Case(In2Sel.CONST_SH): # unsigned - for shift
comb += self.imm_out.data.eq(self.dec.sh)
comb += self.imm_out.ok.eq(1)
- with m.Case(In2Sel.CONST_SH32):
+ with m.Case(In2Sel.CONST_SH32): # unsigned - for shift
comb += self.imm_out.data.eq(self.dec.SH32)
comb += self.imm_out.ok.eq(1)
op = self.dec.op
# BCREG implicitly uses LR or TAR for 2nd reg
# CTR however is already in fast_spr1 *not* 2.
- with m.If(op.internal_op == InternalOp.OP_BCREG):
- xo9 = self.dec.FormXL.XO[9] # 3.0B p38 top bit of XO
- xo5 = self.dec.FormXL.XO[5] # 3.0B p38
+ with m.If(op.internal_op == MicrOp.OP_BCREG):
+ xo9 = self.dec.FormXL.XO[9] # 3.0B p38 top bit of XO
+ xo5 = self.dec.FormXL.XO[5] # 3.0B p38
with m.If(~xo9):
comb += self.fast_out.data.eq(FastRegs.LR)
comb += self.fast_out.ok.eq(1)
# select Register C field
with m.Switch(self.sel_in):
with m.Case(In3Sel.RB):
- comb += self.reg_out.data.eq(self.dec.RB) # for M-Form shiftrot
+ # for M-Form shiftrot
+ comb += self.reg_out.data.eq(self.dec.RB)
comb += self.reg_out.ok.eq(1)
with m.Case(In3Sel.RS):
comb += self.reg_out.data.eq(self.dec.RS)
comb += self.reg_out.ok.eq(1)
with m.Case(OutSel.SPR):
spr = Signal(10, reset_less=True)
- comb += spr.eq(decode_spr_num(self.dec.SPR)) # from XFX
+ comb += spr.eq(decode_spr_num(self.dec.SPR)) # from XFX
# TODO MTSPR 1st spr (fast)
- with m.If(op.internal_op == InternalOp.OP_MTSPR):
+ with m.If(op.internal_op == MicrOp.OP_MTSPR):
with m.Switch(spr):
# fast SPRs
with m.Case(SPR.CTR.value):
comb += self.fast_out.data.eq(FastRegs.SRR1)
comb += self.fast_out.ok.eq(1)
with m.Case(SPR.XER.value):
- pass # do nothing
- # XXX TODO: map to internal SPR numbers
+ pass # do nothing
+ # : map to internal SPR numbers
# XXX TODO: dec and tb not to go through mapping.
with m.Default():
comb += sprmap.spr_i.eq(spr)
comb += self.spr_out.data.eq(sprmap.spr_o)
comb += self.spr_out.ok.eq(1)
- # BC or BCREG: potential implicit register (CTR) NOTE: same in DecodeA
- op = self.dec.op
- with m.If((op.internal_op == InternalOp.OP_BC) |
- (op.internal_op == InternalOp.OP_BCREG)):
- with m.If(~self.dec.BO[2]): # 3.0B p38 BO2=0, use CTR reg
- comb += self.fast_out.data.eq(FastRegs.CTR) # constant: CTR
- comb += self.fast_out.ok.eq(1)
+ with m.Switch(op.internal_op):
- # RFID 1st spr (fast)
- with m.If(op.internal_op == InternalOp.OP_RFID):
- comb += self.fast_out.data.eq(FastRegs.SRR0) # constant: SRR0
- comb += self.fast_out.ok.eq(1)
+ # BC or BCREG: implicit register (CTR) NOTE: same in DecodeA
+ with m.Case(MicrOp.OP_BC, MicrOp.OP_BCREG):
+ with m.If(~self.dec.BO[2]): # 3.0B p38 BO2=0, use CTR reg
+ # constant: CTR
+ comb += self.fast_out.data.eq(FastRegs.CTR)
+ comb += self.fast_out.ok.eq(1)
+
+ # RFID 1st spr (fast)
+ with m.Case(MicrOp.OP_RFID):
+ comb += self.fast_out.data.eq(FastRegs.SRR0) # constant: SRR0
+ comb += self.fast_out.ok.eq(1)
return m
comb = m.d.comb
# update mode LD/ST uses read-reg A also as an output
- with m.If(self.dec.op.upd):
+ with m.If(self.dec.op.upd == LDSTMode.update):
comb += self.reg_out.eq(self.dec.RA)
comb += self.reg_out.ok.eq(1)
- # BC or BCREG: potential implicit register (LR) output
+ # B, BC or BCREG: potential implicit register (LR) output
+ # these give bl, bcl, bclrl, etc.
op = self.dec.op
- with m.If((op.internal_op == InternalOp.OP_BC) |
- (op.internal_op == InternalOp.OP_BCREG)):
- with m.If(self.lk): # "link" mode
- comb += self.fast_out.data.eq(FastRegs.LR) # constant: LR
- comb += self.fast_out.ok.eq(1)
+ with m.Switch(op.internal_op):
+
+ # BC* implicit register (LR)
+ with m.Case(MicrOp.OP_BC, MicrOp.OP_B, MicrOp.OP_BCREG):
+ with m.If(self.lk): # "link" mode
+ comb += self.fast_out.data.eq(FastRegs.LR) # constant: LR
+ comb += self.fast_out.ok.eq(1)
- # RFID 2nd spr (fast)
- with m.If(op.internal_op == InternalOp.OP_RFID):
- comb += self.fast_out.data.eq(FastRegs.SRR1) # constant: SRR1
+ # RFID 2nd spr (fast)
+ with m.Case(MicrOp.OP_RFID):
+ comb += self.fast_out.data.eq(FastRegs.SRR1) # constant: SRR1
comb += self.fast_out.ok.eq(1)
return m
decodes Record bit Rc
"""
+
def __init__(self, dec):
self.dec = dec
self.sel_in = Signal(RC, reset_less=True)
-- actual POWER9 does if we set it on those instructions, for now we
-- test that further down when assigning to the multiplier oe input.
"""
+
def __init__(self, dec):
self.dec = dec
self.sel_in = Signal(RC, reset_less=True)
def elaborate(self, platform):
m = Module()
comb = m.d.comb
+ op = self.dec.op
- # select OE bit out field
- with m.Switch(self.sel_in):
- with m.Case(RC.RC):
- comb += self.oe_out.data.eq(self.dec.OE)
- comb += self.oe_out.ok.eq(1)
+ with m.Switch(op.internal_op):
+
+ # mulhw, mulhwu, mulhd, mulhdu - these *ignore* OE
+ with m.Case(MicrOp.OP_MUL_H64, MicrOp.OP_MUL_H32):
+ pass
+
+ # all other ops decode OE field
+ with m.Default():
+ # select OE bit out field
+ with m.Switch(self.sel_in):
+ with m.Case(RC.RC):
+ comb += self.oe_out.data.eq(self.dec.OE)
+ comb += self.oe_out.ok.eq(1)
return m
+
class DecodeCRIn(Elaboratable):
"""Decodes input CR from instruction
comb += self.whole_reg.eq(0)
with m.Switch(self.sel_in):
with m.Case(CRInSel.NONE):
- pass # No bitfield activated
+ pass # No bitfield activated
with m.Case(CRInSel.CR0):
comb += self.cr_bitfield.data.eq(0)
comb += self.cr_bitfield.ok.eq(1)
comb += self.whole_reg.eq(0)
with m.Switch(self.sel_in):
with m.Case(CROutSel.NONE):
- pass # No bitfield activated
+ pass # No bitfield activated
with m.Case(CROutSel.CR0):
comb += self.cr_bitfield.data.eq(0)
- comb += self.cr_bitfield.ok.eq(self.rc_in) # only when RC=1
+ comb += self.cr_bitfield.ok.eq(self.rc_in) # only when RC=1
with m.Case(CROutSel.BF):
comb += self.cr_bitfield.data.eq(self.dec.FormX.BF)
comb += self.cr_bitfield.ok.eq(1)
return m
-class XerBits:
- def __init__(self):
- self.ca = Signal(2, reset_less=True)
- self.ov = Signal(2, reset_less=True)
- self.so = Signal(reset_less=True)
-
- def ports(self):
- return [self.ca, self.ov, self.so]
-
-
class PowerDecode2(Elaboratable):
+ """PowerDecode2: the main instruction decoder.
+
+ whilst PowerDecode is responsible for decoding the actual opcode, this
+ module encapsulates further specialist, sparse information and
+ expansion of fields that is inconvenient to have in the CSV files.
+ for example: the encoding of the immediates, which are detected
+ and expanded out to their full value from an annotated (enum)
+ representation.
+
+ implicit register usage is also set up, here. for example: OP_BC
+ requires implicitly reading CTR, OP_RFID requires implicitly writing
+ to SRR1 and so on.
+
+ in addition, PowerDecoder2 is responsible for detecting whether
+ instructions are illegal (or privileged) or not, and instead of
+ just leaving at that, *replacing* the instruction to execute with
+ a suitable alternative (trap).
+ """
def __init__(self, dec):
self.dec = dec
self.e = Decode2ToExecute1Type()
- self.valid = Signal() # sync signal
+
+ # state information needed by the Decoder (TODO: this as a Record)
+ self.state = CoreState("dec2")
def ports(self):
return self.dec.ports() + self.e.ports()
def elaborate(self, platform):
m = Module()
comb = m.d.comb
- e, op, do = self.e, self.dec.op, self.e.do
+ e_out, op, do_out = self.e, self.dec.op, self.e.do
+ msr, cia = self.state.msr, self.state.pc
+
+ # fill in for a normal instruction (not an exception)
+ # copy over if non-exception, non-privileged etc. is detected
+ e = Decode2ToExecute1Type()
+ do = e.do
# set up submodule decoders
m.submodules.dec = self.dec
comb += dec_o2.sel_in.eq(op.out_sel)
comb += dec_o2.lk.eq(do.lk)
comb += dec_rc.sel_in.eq(op.rc_sel)
- comb += dec_oe.sel_in.eq(op.rc_sel) # XXX should be OE sel
+ comb += dec_oe.sel_in.eq(op.rc_sel) # XXX should be OE sel
comb += dec_cr_in.sel_in.eq(op.cr_in)
comb += dec_cr_out.sel_in.eq(op.cr_out)
comb += dec_cr_out.rc_in.eq(dec_rc.rc_out.data)
+ # copy "state" over
+ comb += do.msr.eq(msr)
+ comb += do.cia.eq(cia)
+
# set up instruction, pick fn unit
- comb += e.nia.eq(0) # XXX TODO (or remove? not sure yet)
- comb += do.insn_type.eq(op.internal_op) # no op: defaults to OP_ILLEGAL
+ # no op: defaults to OP_ILLEGAL
+ comb += do.insn_type.eq(op.internal_op)
comb += do.fn_unit.eq(op.function_unit)
# registers a, b, c and out and out2 (LD/ST EA)
comb += e.read_reg3.eq(dec_c.reg_out)
comb += e.write_reg.eq(dec_o.reg_out)
comb += e.write_ea.eq(dec_o2.reg_out)
- comb += do.imm_data.eq(dec_b.imm_out) # immediate in RB (usually)
+ comb += do.imm_data.eq(dec_b.imm_out) # immediate in RB (usually)
comb += do.zero_a.eq(dec_a.immz_out) # RA==0 detected
# rc and oe out
# decoded/selected instruction flags
comb += do.data_len.eq(op.ldst_len)
- comb += do.invert_a.eq(op.inv_a)
+ comb += do.invert_in.eq(op.inv_a)
comb += do.invert_out.eq(op.inv_out)
comb += do.input_carry.eq(op.cry_in) # carry comes in
- comb += do.output_carry.eq(op.cry_out) # carry goes out
+ comb += do.output_carry.eq(op.cry_out) # carry goes out
comb += do.is_32bit.eq(op.is_32b)
comb += do.is_signed.eq(op.sgn)
with m.If(op.lk):
- comb += do.lk.eq(self.dec.LK) # XXX TODO: accessor
+ comb += do.lk.eq(self.dec.LK) # XXX TODO: accessor
comb += do.byte_reverse.eq(op.br)
comb += do.sign_extend.eq(op.sgn_ext)
- comb += do.update.eq(op.upd) # LD/ST "update" mode.
+ comb += do.ldst_mode.eq(op.upd) # LD/ST mode (update, cache-inhibit)
# These should be removed eventually
comb += do.input_cr.eq(op.cr_in) # condition reg comes in
- comb += do.output_cr.eq(op.cr_out) # condition reg goes in
+ comb += do.output_cr.eq(op.cr_out) # condition reg goes in
# sigh this is exactly the sort of thing for which the
# decoder is designed to not need. MTSPR, MFSPR and others need
# access to the XER bits. however setting e.oe is not appropriate
- with m.If(op.internal_op == InternalOp.OP_MFSPR):
+ with m.If(op.internal_op == MicrOp.OP_MFSPR):
comb += e.xer_in.eq(1)
- with m.If(op.internal_op == InternalOp.OP_MTSPR):
+ with m.If(op.internal_op == MicrOp.OP_MTSPR):
comb += e.xer_out.eq(1)
# set the trapaddr to 0x700 for a td/tw/tdi/twi operation
- with m.If(op.internal_op == InternalOp.OP_TRAP):
+ with m.If(op.internal_op == MicrOp.OP_TRAP):
+ # *DO NOT* call self.trap here. that would reset absolutely
+ # rverything including destroying read of RA and RB.
comb += do.trapaddr.eq(0x70) # addr=0x700 (strip first nibble)
+ # TODO: get msr, then can do privileged instruction
+ with m.If(instr_is_priv(m, op.internal_op, e.do.insn) & msr[MSR.PR]):
+ # privileged instruction trap
+ self.trap(m, TT.PRIV, 0x700)
+
# illegal instruction must redirect to trap. this is done by
# *overwriting* the decoded instruction and starting again.
# (note: the same goes for interrupts and for privileged operations,
# just with different trapaddr and traptype)
- with m.If(op.internal_op == InternalOp.OP_ILLEGAL):
+ with m.Elif(op.internal_op == MicrOp.OP_ILLEGAL):
# illegal instruction trap
- self.trap(m, TT_ILLEG, 0x700)
+ self.trap(m, TT.ILLEG, 0x700)
+
+ # no exception, just copy things to the output
+ with m.Else():
+ comb += e_out.eq(e)
# trap: (note e.insn_type so this includes OP_ILLEGAL) set up fast regs
# Note: OP_SC could actually be modified to just be a trap
- with m.If((do.insn_type == InternalOp.OP_TRAP) |
- (do.insn_type == InternalOp.OP_SC)):
+ with m.If((do_out.insn_type == MicrOp.OP_TRAP) |
+ (do_out.insn_type == MicrOp.OP_SC)):
# TRAP write fast1 = SRR0
- comb += e.write_fast1.data.eq(FastRegs.SRR0) # constant: SRR0
- comb += e.write_fast1.ok.eq(1)
+ comb += e_out.write_fast1.data.eq(FastRegs.SRR0) # constant: SRR0
+ comb += e_out.write_fast1.ok.eq(1)
# TRAP write fast2 = SRR1
- comb += e.write_fast2.data.eq(FastRegs.SRR1) # constant: SRR1
- comb += e.write_fast2.ok.eq(1)
+ comb += e_out.write_fast2.data.eq(FastRegs.SRR1) # constant: SRR1
+ comb += e_out.write_fast2.ok.eq(1)
# RFID: needs to read SRR0/1
- with m.If(do.insn_type == InternalOp.OP_RFID):
+ with m.If(do_out.insn_type == MicrOp.OP_RFID):
# TRAP read fast1 = SRR0
- comb += e.read_fast1.data.eq(FastRegs.SRR0) # constant: SRR0
- comb += e.read_fast1.ok.eq(1)
+ comb += e_out.read_fast1.data.eq(FastRegs.SRR0) # constant: SRR0
+ comb += e_out.read_fast1.ok.eq(1)
# TRAP read fast2 = SRR1
- comb += e.read_fast2.data.eq(FastRegs.SRR1) # constant: SRR1
- comb += e.read_fast2.ok.eq(1)
+ comb += e_out.read_fast2.data.eq(FastRegs.SRR1) # constant: SRR1
+ comb += e_out.read_fast2.ok.eq(1)
return m
- # TODO: get msr, then can do privileged instruction
- with m.If(instr_is_priv(m, op.internal_op, e.insn) & msr[MSR_PR]):
- # privileged instruction trap
- self.trap(m, TT_PRIV, 0x700)
- return m
-
def trap(self, m, traptype, trapaddr):
"""trap: this basically "rewrites" the decoded instruction as a trap
"""
comb = m.d.comb
- e, op, do = self.e, self.dec.op, self.e.do
- comb += e.eq(0) # reset eeeeeverything
+ op, do, e = self.dec.op, self.e.do, self.e
+ comb += e.eq(0) # reset eeeeeverything
+
# start again
comb += do.insn.eq(self.dec.opcode_in)
- comb += do.insn_type.eq(InternalOp.OP_TRAP)
+ comb += do.insn_type.eq(MicrOp.OP_TRAP)
comb += do.fn_unit.eq(Function.TRAP)
- comb += do.trapaddr.eq(trapaddr >> 4) # cut bottom 4 bits
- comb += do.traptype.eq(traptype) # request type
-
- def regspecmap_read(self, regfile, regname):
- """regspecmap_read: provides PowerDecode2 with an encoding relationship
- to Function Unit port regfiles (read-enable, read regnum, write regnum)
- regfile and regname arguments are fields 1 and 2 from a given regspec.
- """
- return regspec_decode_read(self.e, regfile, regname)
+ comb += do.trapaddr.eq(trapaddr >> 4) # cut bottom 4 bits
+ comb += do.traptype.eq(traptype) # request type
+ comb += do.msr.eq(self.state.msr) # copy of MSR "state"
+ comb += do.cia.eq(self.state.pc) # copy of PC "state"
- def regspecmap_write(self, regfile, regname):
- """regspecmap_write: provides PowerDecode2 with an encoding relationship
- to Function Unit port regfiles (write port, write regnum)
- regfile and regname arguments are fields 1 and 2 from a given regspec.
- """
- return regspec_decode_write(self.e, regfile, regname)
- def rdflags(self, cu):
- rdl = []
- for idx in range(cu.n_src):
- regfile, regname, _ = cu.get_in_spec(idx)
- rdflag, read = self.regspecmap_read(regfile, regname)
- rdl.append(rdflag)
- print ("rdflags", rdl)
- return Cat(*rdl)
+def get_rdflags(e, cu):
+ rdl = []
+ for idx in range(cu.n_src):
+ regfile, regname, _ = cu.get_in_spec(idx)
+ rdflag, read = regspec_decode_read(e, regfile, regname)
+ rdl.append(rdflag)
+ print("rdflags", rdl)
+ return Cat(*rdl)
if __name__ == '__main__':
vl = rtlil.convert(dec2, ports=dec2.ports() + pdecode.ports())
with open("dec2.il", "w") as f:
f.write(vl)
-
projects / soc.git / blobdiff