src/ieee754/fpdiv/divstages.py

   1 # IEEE Floating Point Divider
   2
   3 from nmigen import Module
   4 from nmigen.cli import main, verilog
   5
   6 from nmutil.singlepipe import (StageChain, SimpleHandshake)
   7
   8 from ieee754.fpcommon.fpbase import FPState
   9 from ieee754.fpcommon.denorm import FPSCData
  10 from ieee754.fpcommon.postcalc import FPAddStage1Data
  11
  12 # TODO: write these
  13 from .div0 import FPDivStage0Mod
  14 from .div1 import FPDivStage1Mod
  15
  16
  17 class FPDivStages(FPState, SimpleHandshake):
  18
  19     def __init__(self, width, id_wid):
  20         FPState.__init__(self, "align")
  21         self.width = width
  22         self.id_wid = id_wid
  23         SimpleHandshake.__init__(self, self) # pipeline is its own stage
  24         self.m1o = self.ospec()
  25
  26     def ispec(self):
  27         return FPSCData(self.width, self.id_wid, False)
  28
  29     def ospec(self):
  30         return FPAddStage1Data(self.width, self.id_wid) # AddStage1 ospec
  31
  32     def setup(self, m, i):
  33         """ links module to inputs and outputs
  34         """
  35
  36         # chain DivStage0 and DivStage1
  37         m0mod = FPDivStage0Mod(self.width, self.id_wid)
  38         m1mod = FPDivStage1Mod(self.width, self.id_wid)
  39
  40         chain = StageChain([m0mod, m1mod])
  41         chain.setup(m, i)
  42
  43         self.o = m1mod.o
  44
  45     def process(self, i):
  46         return self.o
  47
  48     def action(self, m):
  49         m.d.sync += self.m1o.eq(self.process(None))
  50         m.next = "normalise_1"
  51
  52