# Copyright (C) Jonathan P Dawson 2013
# 2013-12-12
-from nmigen import Module, Signal, Cat, Mux, Array, Const
-from nmigen.lib.coding import PriorityEncoder
from nmigen.cli import main, verilog
-from math import log
-
-from fpbase import FPNumIn, FPNumOut, FPOp, Overflow, FPBase, FPNumBase
-from fpbase import MultiShiftRMerge, Trigger
-from singlepipe import (ControlBase, StageChain, UnbufferedPipeline,
- PassThroughStage)
-from multipipe import CombMuxOutPipe
-from multipipe import PriorityCombMuxInPipe
-
-from fpbase import FPState, FPID
-from fpcommon.getop import (FPGetOpMod, FPGetOp, FPNumBase2Ops, FPADDBaseData,
- FPGet2OpMod, FPGet2Op)
-from fpcommon.denorm import (FPSCData, FPAddDeNormMod, FPAddDeNorm)
-from fpcommon.postcalc import FPAddStage1Data
-from fpcommon.postnormalise import (FPNorm1Data, FPNorm1ModSingle,
- FPNorm1ModMulti, FPNorm1Single, FPNorm1Multi)
-from fpcommon.roundz import (FPRoundData, FPRoundMod, FPRound)
-from fpcommon.corrections import (FPCorrectionsMod, FPCorrections)
-from fpcommon.pack import (FPPackData, FPPackMod, FPPack)
-from fpcommon.normtopack import FPNormToPack
-from fpcommon.putz import (FPPutZ, FPPutZIdx)
-
-from fpadd.specialcases import (FPAddSpecialCasesMod, FPAddSpecialCases,
- FPAddSpecialCasesDeNorm)
-from fpadd.align import (FPAddAlignMulti, FPAddAlignMultiMod, FPNumIn2Ops,
- FPAddAlignSingleMod, FPAddAlignSingle)
-
-
-class FPAddAlignSingleAdd(FPState, UnbufferedPipeline):
-
- def __init__(self, width, id_wid):
- FPState.__init__(self, "align")
- self.width = width
- self.id_wid = id_wid
- UnbufferedPipeline.__init__(self, self) # pipeline is its own stage
- self.a1o = self.ospec()
-
- def ispec(self):
- return FPSCData(self.width, self.id_wid)
-
- def ospec(self):
- return FPAddStage1Data(self.width, self.id_wid) # AddStage1 ospec
-
- def setup(self, m, i):
- """ links module to inputs and outputs
- """
-
- # chain AddAlignSingle, AddStage0 and AddStage1
- mod = FPAddAlignSingleMod(self.width, self.id_wid)
- a0mod = FPAddStage0Mod(self.width, self.id_wid)
- a1mod = FPAddStage1Mod(self.width, self.id_wid)
-
- chain = StageChain([mod, a0mod, a1mod])
- chain.setup(m, i)
-
- self.o = a1mod.o
-
- def process(self, i):
- return self.o
-
- def action(self, m):
- m.d.sync += self.a1o.eq(self.process(None))
- m.next = "normalise_1"
-
-
-class FPAddStage0Data:
-
- def __init__(self, width, id_wid):
- self.z = FPNumBase(width, False)
- self.out_do_z = Signal(reset_less=True)
- self.oz = Signal(width, reset_less=True)
- self.tot = Signal(self.z.m_width + 4, reset_less=True)
- self.mid = Signal(id_wid, reset_less=True)
-
- def eq(self, i):
- return [self.z.eq(i.z), self.out_do_z.eq(i.out_do_z), self.oz.eq(i.oz),
- self.tot.eq(i.tot), self.mid.eq(i.mid)]
-
-
-class FPAddStage0Mod:
-
- def __init__(self, width, id_wid):
- self.width = width
- self.id_wid = id_wid
- self.i = self.ispec()
- self.o = self.ospec()
-
- def ispec(self):
- return FPSCData(self.width, self.id_wid)
-
- def ospec(self):
- return FPAddStage0Data(self.width, self.id_wid)
-
- def process(self, i):
- return self.o
-
- def setup(self, m, i):
- """ links module to inputs and outputs
- """
- m.submodules.add0 = self
- m.d.comb += self.i.eq(i)
-
- def elaborate(self, platform):
- m = Module()
- m.submodules.add0_in_a = self.i.a
- m.submodules.add0_in_b = self.i.b
- m.submodules.add0_out_z = self.o.z
-
- # store intermediate tests (and zero-extended mantissas)
- seq = Signal(reset_less=True)
- mge = Signal(reset_less=True)
- am0 = Signal(len(self.i.a.m)+1, reset_less=True)
- bm0 = Signal(len(self.i.b.m)+1, reset_less=True)
- m.d.comb += [seq.eq(self.i.a.s == self.i.b.s),
- mge.eq(self.i.a.m >= self.i.b.m),
- am0.eq(Cat(self.i.a.m, 0)),
- bm0.eq(Cat(self.i.b.m, 0))
- ]
- # same-sign (both negative or both positive) add mantissas
- with m.If(~self.i.out_do_z):
- m.d.comb += self.o.z.e.eq(self.i.a.e)
- with m.If(seq):
- m.d.comb += [
- self.o.tot.eq(am0 + bm0),
- self.o.z.s.eq(self.i.a.s)
- ]
- # a mantissa greater than b, use a
- with m.Elif(mge):
- m.d.comb += [
- self.o.tot.eq(am0 - bm0),
- self.o.z.s.eq(self.i.a.s)
- ]
- # b mantissa greater than a, use b
- with m.Else():
- m.d.comb += [
- self.o.tot.eq(bm0 - am0),
- self.o.z.s.eq(self.i.b.s)
- ]
-
- m.d.comb += self.o.oz.eq(self.i.oz)
- m.d.comb += self.o.out_do_z.eq(self.i.out_do_z)
- m.d.comb += self.o.mid.eq(self.i.mid)
- return m
-
-
-class FPAddStage0(FPState):
- """ First stage of add. covers same-sign (add) and subtract
- special-casing when mantissas are greater or equal, to
- give greatest accuracy.
- """
-
- def __init__(self, width, id_wid):
- FPState.__init__(self, "add_0")
- self.mod = FPAddStage0Mod(width)
- self.o = self.mod.ospec()
-
- def setup(self, m, i):
- """ links module to inputs and outputs
- """
- self.mod.setup(m, i)
-
- # NOTE: these could be done as combinatorial (merge add0+add1)
- m.d.sync += self.o.eq(self.mod.o)
-
- def action(self, m):
- m.next = "add_1"
-
-
-class FPAddStage1Mod(FPState):
- """ Second stage of add: preparation for normalisation.
- detects when tot sum is too big (tot[27] is kinda a carry bit)
- """
-
- def __init__(self, width, id_wid):
- self.width = width
- self.id_wid = id_wid
- self.i = self.ispec()
- self.o = self.ospec()
-
- def ispec(self):
- return FPAddStage0Data(self.width, self.id_wid)
-
- def ospec(self):
- return FPAddStage1Data(self.width, self.id_wid)
-
- def process(self, i):
- return self.o
-
- def setup(self, m, i):
- """ links module to inputs and outputs
- """
- m.submodules.add1 = self
- m.submodules.add1_out_overflow = self.o.of
-
- m.d.comb += self.i.eq(i)
-
- def elaborate(self, platform):
- m = Module()
- m.d.comb += self.o.z.eq(self.i.z)
- # tot[-1] (MSB) gets set when the sum overflows. shift result down
- with m.If(~self.i.out_do_z):
- with m.If(self.i.tot[-1]):
- m.d.comb += [
- self.o.z.m.eq(self.i.tot[4:]),
- self.o.of.m0.eq(self.i.tot[4]),
- self.o.of.guard.eq(self.i.tot[3]),
- self.o.of.round_bit.eq(self.i.tot[2]),
- self.o.of.sticky.eq(self.i.tot[1] | self.i.tot[0]),
- self.o.z.e.eq(self.i.z.e + 1)
- ]
- # tot[-1] (MSB) zero case
- with m.Else():
- m.d.comb += [
- self.o.z.m.eq(self.i.tot[3:]),
- self.o.of.m0.eq(self.i.tot[3]),
- self.o.of.guard.eq(self.i.tot[2]),
- self.o.of.round_bit.eq(self.i.tot[1]),
- self.o.of.sticky.eq(self.i.tot[0])
- ]
-
- m.d.comb += self.o.out_do_z.eq(self.i.out_do_z)
- m.d.comb += self.o.oz.eq(self.i.oz)
- m.d.comb += self.o.mid.eq(self.i.mid)
-
- return m
-
-
-class FPAddStage1(FPState):
-
- def __init__(self, width, id_wid):
- FPState.__init__(self, "add_1")
- self.mod = FPAddStage1Mod(width)
- self.out_z = FPNumBase(width, False)
- self.out_of = Overflow()
- self.norm_stb = Signal()
-
- def setup(self, m, i):
- """ links module to inputs and outputs
- """
- self.mod.setup(m, i)
-
- m.d.sync += self.norm_stb.eq(0) # sets to zero when not in add1 state
-
- m.d.sync += self.out_of.eq(self.mod.out_of)
- m.d.sync += self.out_z.eq(self.mod.out_z)
- m.d.sync += self.norm_stb.eq(1)
-
- def action(self, m):
- m.next = "normalise_1"
-
-
-
-
-class FPOpData:
- def __init__(self, width, id_wid):
- self.z = FPOp(width)
- self.mid = Signal(id_wid, reset_less=True)
-
- def eq(self, i):
- return [self.z.eq(i.z), self.mid.eq(i.mid)]
-
- def ports(self):
- return [self.z, self.mid]
-
-
-class FPADDBaseMod:
-
- def __init__(self, width, id_wid=None, single_cycle=False, compact=True):
- """ IEEE754 FP Add
-
- * width: bit-width of IEEE754. supported: 16, 32, 64
- * id_wid: an identifier that is sync-connected to the input
- * single_cycle: True indicates each stage to complete in 1 clock
- * compact: True indicates a reduced number of stages
- """
- self.width = width
- self.id_wid = id_wid
- self.single_cycle = single_cycle
- self.compact = compact
-
- self.in_t = Trigger()
- self.i = self.ispec()
- self.o = self.ospec()
-
- self.states = []
-
- def ispec(self):
- return FPADDBaseData(self.width, self.id_wid)
-
- def ospec(self):
- return FPOpData(self.width, self.id_wid)
-
- def add_state(self, state):
- self.states.append(state)
- return state
-
- def get_fragment(self, platform=None):
- """ creates the HDL code-fragment for FPAdd
- """
- m = Module()
- m.submodules.out_z = self.o.z
- m.submodules.in_t = self.in_t
- if self.compact:
- self.get_compact_fragment(m, platform)
- else:
- self.get_longer_fragment(m, platform)
-
- with m.FSM() as fsm:
-
- for state in self.states:
- with m.State(state.state_from):
- state.action(m)
-
- return m
-
- def get_longer_fragment(self, m, platform=None):
-
- get = self.add_state(FPGet2Op("get_ops", "special_cases",
- self.width))
- get.setup(m, self.i)
- a = get.out_op1
- b = get.out_op2
- get.trigger_setup(m, self.in_t.stb, self.in_t.ack)
-
- sc = self.add_state(FPAddSpecialCases(self.width, self.id_wid))
- sc.setup(m, a, b, self.in_mid)
-
- dn = self.add_state(FPAddDeNorm(self.width, self.id_wid))
- dn.setup(m, a, b, sc.in_mid)
-
- if self.single_cycle:
- alm = self.add_state(FPAddAlignSingle(self.width, self.id_wid))
- alm.setup(m, dn.out_a, dn.out_b, dn.in_mid)
- else:
- alm = self.add_state(FPAddAlignMulti(self.width, self.id_wid))
- alm.setup(m, dn.out_a, dn.out_b, dn.in_mid)
-
- add0 = self.add_state(FPAddStage0(self.width, self.id_wid))
- add0.setup(m, alm.out_a, alm.out_b, alm.in_mid)
-
- add1 = self.add_state(FPAddStage1(self.width, self.id_wid))
- add1.setup(m, add0.out_tot, add0.out_z, add0.in_mid)
-
- if self.single_cycle:
- n1 = self.add_state(FPNorm1Single(self.width, self.id_wid))
- n1.setup(m, add1.out_z, add1.out_of, add0.in_mid)
- else:
- n1 = self.add_state(FPNorm1Multi(self.width, self.id_wid))
- n1.setup(m, add1.out_z, add1.out_of, add1.norm_stb, add0.in_mid)
-
- rn = self.add_state(FPRound(self.width, self.id_wid))
- rn.setup(m, n1.out_z, n1.out_roundz, n1.in_mid)
-
- cor = self.add_state(FPCorrections(self.width, self.id_wid))
- cor.setup(m, rn.out_z, rn.in_mid)
-
- pa = self.add_state(FPPack(self.width, self.id_wid))
- pa.setup(m, cor.out_z, rn.in_mid)
-
- ppz = self.add_state(FPPutZ("pack_put_z", pa.out_z, self.out_z,
- pa.in_mid, self.out_mid))
-
- pz = self.add_state(FPPutZ("put_z", sc.out_z, self.out_z,
- pa.in_mid, self.out_mid))
-
- def get_compact_fragment(self, m, platform=None):
-
-
- get = FPGet2Op("get_ops", "special_cases", self.width, self.id_wid)
- sc = FPAddSpecialCasesDeNorm(self.width, self.id_wid)
- alm = FPAddAlignSingleAdd(self.width, self.id_wid)
- n1 = FPNormToPack(self.width, self.id_wid)
-
- get.trigger_setup(m, self.in_t.stb, self.in_t.ack)
-
- chainlist = [get, sc, alm, n1]
- chain = StageChain(chainlist, specallocate=True)
- chain.setup(m, self.i)
-
- for mod in chainlist:
- sc = self.add_state(mod)
-
- ppz = self.add_state(FPPutZ("pack_put_z", n1.out_z.z, self.o,
- n1.out_z.mid, self.o.mid))
-
- #pz = self.add_state(FPPutZ("put_z", sc.out_z.z, self.o,
- # sc.o.mid, self.o.mid))
-
-
-class FPADDBase(FPState):
-
- def __init__(self, width, id_wid=None, single_cycle=False):
- """ IEEE754 FP Add
-
- * width: bit-width of IEEE754. supported: 16, 32, 64
- * id_wid: an identifier that is sync-connected to the input
- * single_cycle: True indicates each stage to complete in 1 clock
- """
- FPState.__init__(self, "fpadd")
- self.width = width
- self.single_cycle = single_cycle
- self.mod = FPADDBaseMod(width, id_wid, single_cycle)
- self.o = self.ospec()
-
- self.in_t = Trigger()
- self.i = self.ispec()
-
- self.z_done = Signal(reset_less=True) # connects to out_z Strobe
- self.in_accept = Signal(reset_less=True)
- self.add_stb = Signal(reset_less=True)
- self.add_ack = Signal(reset=0, reset_less=True)
-
- def ispec(self):
- return self.mod.ispec()
-
- def ospec(self):
- return self.mod.ospec()
-
- def setup(self, m, i, add_stb, in_mid):
- m.d.comb += [self.i.eq(i),
- self.mod.i.eq(self.i),
- self.z_done.eq(self.mod.o.z.trigger),
- #self.add_stb.eq(add_stb),
- self.mod.in_t.stb.eq(self.in_t.stb),
- self.in_t.ack.eq(self.mod.in_t.ack),
- self.o.mid.eq(self.mod.o.mid),
- self.o.z.v.eq(self.mod.o.z.v),
- self.o.z.stb.eq(self.mod.o.z.stb),
- self.mod.o.z.ack.eq(self.o.z.ack),
- ]
-
- m.d.sync += self.add_stb.eq(add_stb)
- m.d.sync += self.add_ack.eq(0) # sets to zero when not in active state
- m.d.sync += self.o.z.ack.eq(0) # likewise
- #m.d.sync += self.in_t.stb.eq(0)
-
- m.submodules.fpadd = self.mod
-
- def action(self, m):
-
- # in_accept is set on incoming strobe HIGH and ack LOW.
- m.d.comb += self.in_accept.eq((~self.add_ack) & (self.add_stb))
-
- #with m.If(self.in_t.ack):
- # m.d.sync += self.in_t.stb.eq(0)
- with m.If(~self.z_done):
- # not done: test for accepting an incoming operand pair
- with m.If(self.in_accept):
- m.d.sync += [
- self.add_ack.eq(1), # acknowledge receipt...
- self.in_t.stb.eq(1), # initiate add
- ]
- with m.Else():
- m.d.sync += [self.add_ack.eq(0),
- self.in_t.stb.eq(0),
- self.o.z.ack.eq(1),
- ]
- with m.Else():
- # done: acknowledge, and write out id and value
- m.d.sync += [self.add_ack.eq(1),
- self.in_t.stb.eq(0)
- ]
- m.next = "put_z"
-
- return
-
- if self.in_mid is not None:
- m.d.sync += self.out_mid.eq(self.mod.out_mid)
-
- m.d.sync += [
- self.out_z.v.eq(self.mod.out_z.v)
- ]
- # move to output state on detecting z ack
- with m.If(self.out_z.trigger):
- m.d.sync += self.out_z.stb.eq(0)
- m.next = "put_z"
- with m.Else():
- m.d.sync += self.out_z.stb.eq(1)
-
-
-class FPADDBasePipe(ControlBase):
- def __init__(self, width, id_wid):
- ControlBase.__init__(self)
- self.pipe1 = FPAddSpecialCasesDeNorm(width, id_wid)
- self.pipe2 = FPAddAlignSingleAdd(width, id_wid)
- self.pipe3 = FPNormToPack(width, id_wid)
-
- self._eqs = self.connect([self.pipe1, self.pipe2, self.pipe3])
-
- def elaborate(self, platform):
- m = Module()
- m.submodules.scnorm = self.pipe1
- m.submodules.addalign = self.pipe2
- m.submodules.normpack = self.pipe3
- m.d.comb += self._eqs
- return m
-
-
-class FPADDInMuxPipe(PriorityCombMuxInPipe):
- def __init__(self, width, id_wid, num_rows):
- self.num_rows = num_rows
- def iospec(): return FPADDBaseData(width, id_wid)
- stage = PassThroughStage(iospec)
- PriorityCombMuxInPipe.__init__(self, stage, p_len=self.num_rows)
-
-
-class FPADDMuxOutPipe(CombMuxOutPipe):
- def __init__(self, width, id_wid, num_rows):
- self.num_rows = num_rows
- def iospec(): return FPPackData(width, id_wid)
- stage = PassThroughStage(iospec)
- CombMuxOutPipe.__init__(self, stage, n_len=self.num_rows)
-
-
-class FPADDMuxInOut:
- """ Reservation-Station version of FPADD pipeline.
-
- * fan-in on inputs (an array of FPADDBaseData: a,b,mid)
- * 3-stage adder pipeline
- * fan-out on outputs (an array of FPPackData: z,mid)
-
- Fan-in and Fan-out are combinatorial.
- """
- def __init__(self, width, id_wid, num_rows):
- self.num_rows = num_rows
- self.inpipe = FPADDInMuxPipe(width, id_wid, num_rows) # fan-in
- self.fpadd = FPADDBasePipe(width, id_wid) # add stage
- self.outpipe = FPADDMuxOutPipe(width, id_wid, num_rows) # fan-out
-
- self.p = self.inpipe.p # kinda annoying,
- self.n = self.outpipe.n # use pipe in/out as this class in/out
- self._ports = self.inpipe.ports() + self.outpipe.ports()
-
- def elaborate(self, platform):
- m = Module()
- m.submodules.inpipe = self.inpipe
- m.submodules.fpadd = self.fpadd
- m.submodules.outpipe = self.outpipe
-
- m.d.comb += self.inpipe.n.connect_to_next(self.fpadd.p)
- m.d.comb += self.fpadd.connect_to_next(self.outpipe)
-
- return m
-
- def ports(self):
- return self._ports
-
-
-class FPADD(FPID):
- """ FPADD: stages as follows:
-
- FPGetOp (a)
- |
- FPGetOp (b)
- |
- FPAddBase---> FPAddBaseMod
- | |
- PutZ GetOps->Specials->Align->Add1/2->Norm->Round/Pack->PutZ
-
- FPAddBase is tricky: it is both a stage and *has* stages.
- Connection to FPAddBaseMod therefore requires an in stb/ack
- and an out stb/ack. Just as with Add1-Norm1 interaction, FPGetOp
- needs to be the thing that raises the incoming stb.
- """
-
- def __init__(self, width, id_wid=None, single_cycle=False, rs_sz=2):
- """ IEEE754 FP Add
-
- * width: bit-width of IEEE754. supported: 16, 32, 64
- * id_wid: an identifier that is sync-connected to the input
- * single_cycle: True indicates each stage to complete in 1 clock
- """
- self.width = width
- self.id_wid = id_wid
- self.single_cycle = single_cycle
-
- #self.out_z = FPOp(width)
- self.ids = FPID(id_wid)
-
- rs = []
- for i in range(rs_sz):
- in_a = FPOp(width)
- in_b = FPOp(width)
- in_a.name = "in_a_%d" % i
- in_b.name = "in_b_%d" % i
- rs.append((in_a, in_b))
- self.rs = Array(rs)
-
- res = []
- for i in range(rs_sz):
- out_z = FPOp(width)
- out_z.name = "out_z_%d" % i
- res.append(out_z)
- self.res = Array(res)
-
- self.states = []
-
- def add_state(self, state):
- self.states.append(state)
- return state
-
- def get_fragment(self, platform=None):
- """ creates the HDL code-fragment for FPAdd
- """
- m = Module()
- m.submodules += self.rs
-
- in_a = self.rs[0][0]
- in_b = self.rs[0][1]
-
- geta = self.add_state(FPGetOp("get_a", "get_b",
- in_a, self.width))
- geta.setup(m, in_a)
- a = geta.out_op
-
- getb = self.add_state(FPGetOp("get_b", "fpadd",
- in_b, self.width))
- getb.setup(m, in_b)
- b = getb.out_op
-
- ab = FPADDBase(self.width, self.id_wid, self.single_cycle)
- ab = self.add_state(ab)
- abd = ab.ispec() # create an input spec object for FPADDBase
- m.d.sync += [abd.a.eq(a), abd.b.eq(b), abd.mid.eq(self.ids.in_mid)]
- ab.setup(m, abd, getb.out_decode, self.ids.in_mid)
- o = ab.o
-
- pz = self.add_state(FPPutZIdx("put_z", o.z, self.res,
- o.mid, "get_a"))
-
- with m.FSM() as fsm:
-
- for state in self.states:
- with m.State(state.state_from):
- state.action(m)
-
- return m
-
+from fpadd.statemachine import FPADDBase, FPADD
+from fpadd.pipeline import FPADDMuxInOut
if __name__ == "__main__":
if True: