from nmigen import Module, Elaboratable, Signal, Mux, Const, Cat, Repl, Record
from nmigen.cli import rtlil
+from nmutil.util import sel
+
from soc.regfile.regfiles import XERRegs
from nmutil.picker import PriorityPicker
from soc.experiment.mem_types import LDSTException
+from soc.decoder.power_svp64_prefix import SVP64PrefixDecoder
+from soc.decoder.power_svp64_extra import SVP64CRExtra, SVP64RegExtra
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.decode2execute1 import (Decode2ToExecute1Type, Data,
Decode2ToOperand)
from soc.sv.svp64 import SVP64Rec
-from soc.consts import (MSR, sel, SPEC, EXTRA2, EXTRA3, SVP64P, field,
- SPEC_SIZE, SPECb, SPEC_AUG_SIZE)
+from soc.consts import (MSR, SPEC, EXTRA2, EXTRA3, SVP64P, field,
+ SPEC_SIZE, SPECb, SPEC_AUG_SIZE, SVP64CROffs)
from soc.regfile.regfiles import FastRegs
from soc.consts import TT
return m
-class SVP64ExtraSpec(Elaboratable):
- """SVP64ExtraSpec - decodes SVP64 Extra specification.
-
- selects the required EXTRA2/3 field.
-
- see https://libre-soc.org/openpower/sv/svp64/
- """
- def __init__(self):
- self.extra = Signal(9, reset_less=True)
- self.etype = Signal(SVEtype, reset_less=True) # 2 or 3 bits
- self.idx = Signal(SVEXTRA, reset_less=True) # which part of extra
- self.spec = Signal(3) # EXTRA spec for the register
-
- def elaborate(self, platform):
- m = Module()
- comb = m.d.comb
- spec = self.spec
- extra = self.extra
-
- # back in the LDSTRM-* and RM-* files generated by sv_analysis.py
- # we marked every op with an Etype: EXTRA2 or EXTRA3, and also said
- # which of the 4 (or 3 for EXTRA3) sub-fields of bits 10:18 contain
- # the register-extension information. extract those now
- with m.Switch(self.etype):
- # 2-bit index selection mode
- with m.Case(SVEtype.EXTRA2):
- with m.Switch(self.idx):
- with m.Case(SVEXTRA.Idx0): # 1st 2 bits [0:1]
- comb += spec[SPEC.VEC].eq(extra[EXTRA2.IDX0_VEC])
- comb += spec[SPEC.MSB].eq(extra[EXTRA2.IDX0_MSB])
- with m.Case(SVEXTRA.Idx1): # 2nd 2 bits [2:3]
- comb += spec[SPEC.VEC].eq(extra[EXTRA2.IDX1_VEC])
- comb += spec[SPEC.MSB].eq(extra[EXTRA2.IDX1_MSB])
- with m.Case(SVEXTRA.Idx2): # 3rd 2 bits [4:5]
- comb += spec[SPEC.VEC].eq(extra[EXTRA2.IDX2_VEC])
- comb += spec[SPEC.MSB].eq(extra[EXTRA2.IDX2_MSB])
- with m.Case(SVEXTRA.Idx3): # 4th 2 bits [6:7]
- comb += spec[SPEC.VEC].eq(extra[EXTRA2.IDX3_VEC])
- comb += spec[SPEC.MSB].eq(extra[EXTRA2.IDX3_MSB])
- # 3-bit index selection mode
- with m.Case(SVEtype.EXTRA3):
- with m.Switch(self.idx):
- with m.Case(SVEXTRA.Idx0): # 1st 3 bits [0:2]
- comb += spec.eq(sel(extra, EXTRA3.IDX0))
- with m.Case(SVEXTRA.Idx1): # 2nd 3 bits [3:5]
- comb += spec.eq(sel(extra, EXTRA3.IDX1))
- with m.Case(SVEXTRA.Idx2): # 3rd 3 bits [6:8]
- comb += spec.eq(sel(extra, EXTRA3.IDX2))
- # cannot fit more than 9 bits so there is no 4th thing
-
- return m
-
-
-class SVP64RegExtra(SVP64ExtraSpec):
- """SVP64RegExtra - decodes SVP64 Extra fields to determine reg extension
-
- incoming 5-bit GPR/FP is turned into a 7-bit and marked as scalar/vector
- depending on info in one of the positions in the EXTRA field.
-
- designed so that "no change" to the 5-bit register number occurs if
- SV either does not apply or the relevant EXTRA2/3 field bits are zero.
-
- see https://libre-soc.org/openpower/sv/svp64/
- """
- def __init__(self):
- SVP64ExtraSpec.__init__(self)
- self.reg_in = Signal(5) # incoming reg number (5 bits, RA, RB)
- self.reg_out = Signal(7) # extra-augmented output (7 bits)
- self.isvec = Signal(1) # reg is marked as vector if true
-
- def elaborate(self, platform):
- m = super().elaborate(platform) # select required EXTRA2/3
- comb = m.d.comb
-
- # first get the spec. if not changed it's "scalar identity behaviour"
- # which is zero which is ok.
- spec = self.spec
-
- # now decode it. bit 0 is "scalar/vector". note that spec could be zero
- # from above, which (by design) has the effect of "no change", below.
-
- # simple: isvec is top bit of spec
- comb += self.isvec.eq(spec[SPEC.VEC])
- # extra bits for register number augmentation
- spec_aug = Signal(SPEC_AUG_SIZE)
- comb += spec_aug.eq(field(spec, SPECb.MSB, SPECb.LSB, SPEC_SIZE))
-
- # decode vector differently from scalar
- with m.If(self.isvec):
- # Vector: shifted up, extra in LSBs (RA << 2) | spec[1:2]
- comb += self.reg_out.eq(Cat(spec_aug, self.reg_in))
- with m.Else():
- # Scalar: not shifted up, extra in MSBs RA | (spec[1:2] << 5)
- comb += self.reg_out.eq(Cat(self.reg_in, spec_aug))
-
- return m
-
-
-class SVP64CRExtra(SVP64ExtraSpec):
- """SVP64CRExtra - decodes SVP64 Extra fields to determine CR extension
-
- incoming 3-bit CR is turned into a 7-bit and marked as scalar/vector
- depending on info in one of the positions in the EXTRA field.
-
- yes, really, 128 CRs. INT is 128, FP is 128, therefore CRs are 128.
-
- designed so that "no change" to the 3-bit CR register number occurs if
- SV either does not apply or the relevant EXTRA2/3 field bits are zero.
-
- see https://libre-soc.org/openpower/sv/svp64/appendix
- """
- def __init__(self):
- SVP64ExtraSpec.__init__(self)
- self.cr_in = Signal(3) # incoming CR number (3 bits, BA[0:2], BFA)
- self.cr_out = Signal(7) # extra-augmented CR output (7 bits)
- self.isvec = Signal(1) # reg is marked as vector if true
-
- def elaborate(self, platform):
- m = super().elaborate(platform) # select required EXTRA2/3
- comb = m.d.comb
-
- # first get the spec. if not changed it's "scalar identity behaviour"
- # which is zero which is ok.
- spec = self.spec
-
- # now decode it. bit 0 is "scalar/vector". note that spec could be zero
- # from above, which (by design) has the effect of "no change", below.
-
- # simple: isvec is top bit of spec
- comb += self.isvec.eq(spec[SPEC.VEC])
- # extra bits for register number augmentation
- spec_aug = Signal(SPEC_AUG_SIZE)
- comb += spec_aug.eq(field(spec, SPECb.MSB, SPECb.LSB, SPEC_SIZE))
-
- # decode vector differently from scalar, insert bits 1 and 2 accordingly
- with m.If(self.isvec):
- # Vector: shifted up, extra in LSBs (CR << 4) | (spec[1:2] << 2)
- comb += self.cr_out.eq(Cat(Const(0, 2), spec_aug, self.cr_in))
- with m.Else():
- # Scalar: not shifted up, extra in MSBs CR | (spec[1:2] << 3)
- comb += self.cr_out.eq(Cat(self.cr_in, spec_aug))
-
- return m
-
-
class DecodeA(Elaboratable):
"""DecodeA from instruction
comb += self.whole_reg.ok.eq(0)
comb += self.sv_override.eq(0)
+ # please note these MUST match (setting of cr_bitfield.ok) exactly
+ # with write_cr0 below in PowerDecoder2. the reason it's separated
+ # is to avoid having duplicate copies of DecodeCROut in multiple
+ # PowerDecoderSubsets. register decoding should be a one-off in
+ # PowerDecoder2. see https://bugs.libre-soc.org/show_bug.cgi?id=606
+
with m.Switch(self.sel_in):
with m.Case(CROutSel.NONE):
pass # No bitfield activated
return subset
def rowsubsetfn(self, opcode, row):
- return row['unit'] == self.fn_name
+ """select per-Function-Unit subset of opcodes to be processed
+
+ normally this just looks at the "unit" column. MMU is different
+ in that it processes specific SPR set/get operations that the SPR
+ pipeline should not.
+ """
+ return (row['unit'] == self.fn_name or
+ # sigh a dreadful hack: MTSPR and MFSPR need to be processed
+ # by the MMU pipeline so we direct those opcodes to MMU **AND**
+ # SPR pipelines, then selectively weed out the SPRs that should
+ # or should not not go to each pipeline, further down.
+ # really this should be done by modifying the CSV syntax
+ # to support multiple tasks (unit column multiple entries)
+ # see https://bugs.libre-soc.org/show_bug.cgi?id=310
+ (self.fn_name == 'MMU' and row['unit'] == 'SPR' and
+ row['internal op'] in ['OP_MTSPR', 'OP_MFSPR'])
+ )
def ports(self):
return self.dec.ports() + self.e.ports() + self.sv_rm.ports()
state = self.state
op, do = self.dec.op, self.do
msr, cia = state.msr, state.pc
-
# fill in for a normal instruction (not an exception)
# copy over if non-exception, non-privileged etc. is detected
if not self.final:
# set up submodule decoders
m.submodules.dec = self.dec
- m.submodules.dec_rc = dec_rc = DecodeRC(self.dec)
+ m.submodules.dec_rc = self.dec_rc = dec_rc = DecodeRC(self.dec)
m.submodules.dec_oe = dec_oe = DecodeOE(self.dec)
- m.submodules.dec_cr_in = self.dec_cr_in = DecodeCRIn(self.dec)
- m.submodules.dec_cr_out = self.dec_cr_out = DecodeCROut(self.dec)
# copy instruction through...
- for i in [do.insn,
- dec_rc.insn_in, dec_oe.insn_in,
- self.dec_cr_in.insn_in, self.dec_cr_out.insn_in]:
+ for i in [do.insn, dec_rc.insn_in, dec_oe.insn_in, ]:
comb += i.eq(self.dec.opcode_in)
# ...and subdecoders' input fields
comb += dec_rc.sel_in.eq(op.rc_sel)
comb += dec_oe.sel_in.eq(op.rc_sel) # XXX should be OE sel
- comb += self.dec_cr_in.sel_in.eq(op.cr_in)
- comb += self.dec_cr_out.sel_in.eq(op.cr_out)
- comb += self.dec_cr_out.rc_in.eq(dec_rc.rc_out.data)
# copy "state" over
comb += self.do_copy("msr", msr)
# set up instruction type
# no op: defaults to OP_ILLEGAL
- if self.fn_name=="MMU":
- # mmu is special case: needs SPR opcode as well
- mmu0 = self.mmu0_spr_dec
- with m.If(((mmu0.dec.op.internal_op == MicrOp.OP_MTSPR) |
- (mmu0.dec.op.internal_op == MicrOp.OP_MFSPR))):
- comb += self.do_copy("insn_type", mmu0.op_get("internal_op"))
- with m.Else():
- comb += self.do_copy("insn_type", self.op_get("internal_op"))
- else:
- comb += self.do_copy("insn_type", self.op_get("internal_op"))
+ internal_op = self.op_get("internal_op")
+ comb += self.do_copy("insn_type", internal_op)
# function unit for decoded instruction: requires minor redirect
# for SPR set/get
spr = Signal(10, reset_less=True)
comb += spr.eq(decode_spr_num(self.dec.SPR)) # from XFX
- # XXX BUG - don't use hardcoded magic constants.
- # also use ".value" otherwise the test fails. bit of a pain
- # https://bugs.libre-soc.org/show_bug.cgi?id=603
-
- SPR_PID = 48 # TODO read docs for POWER9
# Microwatt doesn't implement the partition table
- # instead has PRTBL register (SPR) to point to process table
- SPR_PRTBL = 720 # see common.vhdl in microwatt, not in POWER9
- with m.If(((self.dec.op.internal_op == MicrOp.OP_MTSPR) |
- (self.dec.op.internal_op == MicrOp.OP_MFSPR)) &
- ((spr == SPR.DSISR) | (spr == SPR.DAR)
- | (spr==SPR_PRTBL) | (spr==SPR_PID))):
- comb += self.do_copy("fn_unit", Function.MMU)
+ # instead has PRTBL(SVSRR0) register (SPR) to point to process table
+ is_spr_mv = Signal()
+ is_mmu_spr = Signal()
+ comb += is_spr_mv.eq((internal_op == MicrOp.OP_MTSPR) |
+ (internal_op == MicrOp.OP_MFSPR))
+ comb += is_mmu_spr.eq((spr == SPR.DSISR.value) |
+ (spr == SPR.DAR.value) |
+ (spr == SPR.SVSRR0.value) |
+ (spr == SPR.PIDR.value))
+ # MMU must receive MMU SPRs
+ with m.If(is_spr_mv & (fn == Function.SPR) & is_mmu_spr):
+ comb += self.do_copy("fn_unit", Function.NONE)
+ comb += self.do_copy("insn_type", MicrOp.OP_ILLEGAL)
+ # SPR pipe must *not* receive MMU SPRs
+ with m.Elif(is_spr_mv & (fn == Function.MMU) & ~is_mmu_spr):
+ comb += self.do_copy("fn_unit", Function.NONE)
+ comb += self.do_copy("insn_type", MicrOp.OP_ILLEGAL)
+ # all others ok
with m.Else():
- comb += self.do_copy("fn_unit",fn)
+ comb += self.do_copy("fn_unit", fn)
# immediates
if self.needs_field("zero_a", "in1_sel"):
comb += self.do_copy("rc", dec_rc.rc_out)
comb += self.do_copy("oe", dec_oe.oe_out)
- # CR in/out
- comb += self.do_copy("read_cr_whole", self.dec_cr_in.whole_reg)
- comb += self.do_copy("write_cr_whole", self.dec_cr_out.whole_reg)
- comb += self.do_copy("write_cr0", self.dec_cr_out.cr_bitfield.ok)
+ # CR in/out - note: these MUST match with what happens in
+ # DecodeCROut!
+ rc_out = self.dec_rc.rc_out.data
+ with m.Switch(op.cr_out):
+ with m.Case(CROutSel.CR0, CROutSel.CR1):
+ comb += self.do_copy("write_cr0", rc_out) # only when RC=1
+ with m.Case(CROutSel.BF, CROutSel.BT):
+ comb += self.do_copy("write_cr0", 1)
comb += self.do_copy("input_cr", self.op_get("cr_in")) # CR in
comb += self.do_copy("output_cr", self.op_get("cr_out")) # CR out
self.in3_isvec = Signal(1, name="reg_c_isvec")
self.o_isvec = Signal(1, name="reg_o_isvec")
self.o2_isvec = Signal(1, name="reg_o2_isvec")
+ self.no_in_vec = Signal(1, name="no_in_vec") # no inputs are vectors
self.no_out_vec = Signal(1, name="no_out_vec") # no outputs are vectors
def get_col_subset(self, opkls):
state = self.state
e_out, op, do_out = self.e, self.dec.op, self.e.do
dec_spr, msr, cia, ext_irq = state.dec, state.msr, state.pc, state.eint
+ rc_out = self.dec_rc.rc_out.data
e = self.e_tmp
do = e.do
m.submodules.dec_c = dec_c = DecodeC(self.dec)
m.submodules.dec_o = dec_o = DecodeOut(self.dec)
m.submodules.dec_o2 = dec_o2 = DecodeOut2(self.dec)
+ m.submodules.dec_cr_in = self.dec_cr_in = DecodeCRIn(self.dec)
+ m.submodules.dec_cr_out = self.dec_cr_out = DecodeCROut(self.dec)
# and SVP64 Extra decoders
m.submodules.crout_svdec = crout_svdec = SVP64CRExtra()
# copy instruction through...
for i in [do.insn, dec_a.insn_in, dec_b.insn_in,
+ self.dec_cr_in.insn_in, self.dec_cr_out.insn_in,
dec_c.insn_in, dec_o.insn_in, dec_o2.insn_in]:
comb += i.eq(self.dec.opcode_in)
+ # CR setup
+ comb += self.dec_cr_in.sel_in.eq(op.cr_in)
+ comb += self.dec_cr_out.sel_in.eq(op.cr_out)
+ comb += self.dec_cr_out.rc_in.eq(rc_out)
+
+ # CR register info
+ comb += self.do_copy("read_cr_whole", self.dec_cr_in.whole_reg)
+ comb += self.do_copy("write_cr_whole", self.dec_cr_out.whole_reg)
+
# now do the SVP64 munging. op.SV_Etype and op.sv_in1 comes from
# PowerDecoder which in turn comes from LDST-RM*.csv and RM-*.csv
# which in turn were auto-generated by sv_analysis.py
# "update mode" rather than specified cleanly as its own CSV column
#comb += o2_svdec.idx.eq(op.sv_out) # SVP64 output (implicit)
- # output reg-is-vectorised (and when no output is vectorised)
+ # output reg-is-vectorised (and when no input or output is vectorised)
comb += self.in1_isvec.eq(in1_svdec.isvec)
comb += self.in2_isvec.eq(in2_svdec.isvec)
comb += self.in3_isvec.eq(in3_svdec.isvec)
comb += self.o_isvec.eq(o_svdec.isvec)
comb += self.o2_isvec.eq(o2_svdec.isvec)
- # TODO: include SPRs and CRs here! must be True when *all* are scalar
- comb += self.no_out_vec.eq((~o2_svdec.isvec) & (~o_svdec.isvec))
+ # TODO add SPRs here. must be True when *all* are scalar
+ l = map(lambda svdec: svdec.isvec, [in1_svdec, in2_svdec, in3_svdec,
+ crin_svdec, crin_svdec_b, crin_svdec_o])
+ comb += self.no_in_vec.eq(~Cat(*l).bool()) # all input scalar
+ l = map(lambda svdec: svdec.isvec, [o2_svdec, o_svdec, crout_svdec])
+ comb += self.no_out_vec.eq(~Cat(*l).bool()) # all output scalar
# SPRs out
comb += e.read_spr1.eq(dec_a.spr_out)
comb += svdec.cr_in.eq(fromreg.data) # 3-bit (CR0/BC/BFA)
with m.If(svdec.isvec):
# check if this is CR0 or CR1: treated differently
- # (does not "listen" to EXTRA2/3 spec
+ # (does not "listen" to EXTRA2/3 spec for a start)
+ # also: the CRs start from completely different locations
with m.If(cr.sv_override == 1): # CR0
- comb += to_reg.data.eq(srcstep+0) # XXX TODO CR0 offset
+ offs = SVP64CROffs.CR0
+ comb += to_reg.data.eq(srcstep+offs)
with m.Elif(cr.sv_override == 2): # CR1
- comb += to_reg.data.eq(srcstep+1) # XXX TODO CR1 offset
+ offs = SVP64CROffs.CR1
+ comb += to_reg.data.eq(srcstep+1)
with m.Else():
comb += to_reg.data.eq(srcstep+svdec.cr_out) # 7-bit output
with m.Else():
comb += self.do_copy("cia", self.state.pc, True) # copy of PC "state"
-# SVP64 Prefix fields: see https://libre-soc.org/openpower/sv/svp64/
-# identifies if an instruction is a SVP64-encoded prefix, and extracts
-# the 24-bit SVP64 context (RM) if it is
-class SVP64PrefixDecoder(Elaboratable):
-
- def __init__(self):
- self.opcode_in = Signal(32, reset_less=True)
- self.raw_opcode_in = Signal.like(self.opcode_in, reset_less=True)
- self.is_svp64_mode = Signal(1, reset_less=True)
- self.svp64_rm = Signal(24, reset_less=True)
- self.bigendian = Signal(reset_less=True)
-
- def elaborate(self, platform):
- m = Module()
- opcode_in = self.opcode_in
- comb = m.d.comb
- # sigh copied this from TopPowerDecoder
- # raw opcode in assumed to be in LE order: byte-reverse it to get BE
- raw_le = self.raw_opcode_in
- l = []
- for i in range(0, 32, 8):
- l.append(raw_le[i:i+8])
- l.reverse()
- raw_be = Cat(*l)
- comb += opcode_in.eq(Mux(self.bigendian, raw_be, raw_le))
-
- # start identifying if the incoming opcode is SVP64 prefix)
- major = Signal(6, reset_less=True)
- ident = Signal(2, reset_less=True)
-
- comb += major.eq(sel(opcode_in, SVP64P.OPC))
- comb += ident.eq(sel(opcode_in, SVP64P.SVP64_7_9))
-
- comb += self.is_svp64_mode.eq(
- (major == Const(1, 6)) & # EXT01
- (ident == Const(0b11, 2)) # identifier bits
- )
-
- with m.If(self.is_svp64_mode):
- # now grab the 24-bit ReMap context bits,
- comb += self.svp64_rm.eq(sel(opcode_in, SVP64P.RM))
-
- return m
-
- def ports(self):
- return [self.opcode_in, self.raw_opcode_in, self.is_svp64_mode,
- self.svp64_rm, self.bigendian]
def get_rdflags(e, cu):
rdl = []
if __name__ == '__main__':
- svp64 = SVP64PowerDecoder()
- vl = rtlil.convert(svp64, ports=svp64.ports())
- with open("svp64_dec.il", "w") as f:
- f.write(vl)
pdecode = create_pdecode()
dec2 = PowerDecode2(pdecode)
vl = rtlil.convert(dec2, ports=dec2.ports() + pdecode.ports())
projects / soc.git / blobdiff