src/ieee754/fpcommon/normtopack.py

   1 # IEEE Floating Point Adder (Single Precision)
   2 # Copyright (C) Jonathan P Dawson 2013
   3 # 2013-12-12
   4
   5 #from nmigen.cli import main, verilog
   6
   7 from nmutil.singlepipe import StageChain, SimpleHandshake
   8
   9 from ieee754.fpcommon.fpbase import FPState, FPID
  10 from .postcalc import FPAddStage1Data
  11 from .postnormalise import FPNorm1ModSingle
  12 from .roundz import FPRoundMod
  13 from .corrections import FPCorrectionsMod
  14 from .pack import FPPackData, FPPackMod
  15
  16
  17 class FPNormToPack(FPState, SimpleHandshake):
  18
  19     def __init__(self, width, pspec):
  20         FPState.__init__(self, "normalise_1")
  21         self.pspec = pspec
  22         self.width = width
  23         SimpleHandshake.__init__(self, self) # pipeline is its own stage
  24
  25     def ispec(self):
  26         return FPAddStage1Data(self.width, self.pspec)
  27
  28     def ospec(self):
  29         return FPPackData(self.width, self.pspec) # FPPackMod
  30
  31     def setup(self, m, i):
  32         """ links module to inputs and outputs
  33         """
  34
  35         # Normalisation, Rounding Corrections, Pack - in a chain
  36         nmod = FPNorm1ModSingle(self.width, self.pspec)
  37         rmod = FPRoundMod(self.width, self.pspec)
  38         cmod = FPCorrectionsMod(self.width, self.pspec)
  39         pmod = FPPackMod(self.width, self.pspec)
  40         stages = [nmod, rmod, cmod, pmod]
  41         chain = StageChain(stages)
  42         chain.setup(m, i)
  43         self.out_z = pmod.ospec()
  44
  45         self.o = pmod.o
  46
  47     def process(self, i):
  48         return self.o
  49
  50     def action(self, m):
  51         m.d.sync += self.out_z.eq(self.process(None))
  52         m.next = "pack_put_z"