src/ieee754/fpcommon/modbase.py

   1 from nmigen import Elaboratable
   2 from ieee754.pipeline import DynamicPipe
   3 from nmutil.singlepipe import StageChain
   4
   5
   6 class FPModBase(Elaboratable):
   7     """FPModBase: common code between nearly every pipeline module
   8     """
   9     def __init__(self, pspec, modname):
  10         self.modname = modname # use this to give a name to this module
  11         self.pspec = pspec
  12         self.i = self.ispec()
  13         self.o = self.ospec()
  14
  15     def process(self, i):
  16         return self.o
  17
  18     def setup(self, m, i):
  19         """ links module to inputs and outputs
  20         """
  21         setattr(m.submodules, self.modname, self)
  22         m.d.comb += self.i.eq(i)
  23
  24
  25 class FPModBaseChain(DynamicPipe):
  26     """FPModBaseChain: common code between stage-chained pipes
  27
  28     Links a set of combinatorial modules (get_chain) together
  29     and uses pspec.pipekls to dynamically select the pipeline type
  30     Also conforms to the Pipeline Stage API
  31     """
  32     def __init__(self, pspec):
  33         self.pspec = pspec
  34         self.chain = self.get_chain()
  35         super().__init__(pspec)
  36
  37     def ispec(self):
  38         """ returns the input spec of the first module in the chain
  39         """
  40         return self.chain[0].ispec()
  41
  42     def ospec(self):
  43         """ returns the output spec of the last module in the chain
  44         """
  45         return self.chain[-1].ospec()
  46
  47     def process(self, i):
  48         return self.o # ... returned here (see setup comment below)
  49
  50     def setup(self, m, i):
  51         """ links module to inputs and outputs
  52         """
  53         StageChain(self.chain).setup(m, i) # input linked here, through chain
  54         self.o = self.chain[-1].o # output is the last thing in the chain...