src/ieee754/pipeline.py

   1 # SPDX-License-Identifier: LGPL-2.1-or-later
   2 # See Notices.txt for copyright information
   3
   4 from nmutil.singlepipe import SimpleHandshake
   5 from nmutil.dynamicpipe import DynamicPipe, SimpleHandshakeRedir
   6
   7
   8 class PipelineSpec:
   9     """ Pipeline Specification base class.
  10
  11     :attribute width: the IEEE754 FP bitwidth
  12     :attribute id_wid: the Reservation Station muxid bitwidth
  13     :attribute op_wid: an "operand bitwidth" passed down all stages
  14     :attribute opkls: an optional class that is instantiated as the "operand"
  15
  16     See ieee754/fpcommon/getop FPPipeContext for how (where) PipelineSpec
  17     is used.  FPPipeContext is passed down *every* stage of a pipeline
  18     and contains the Reservation Station multiplexer ID as well as
  19     an optional "operand".  This "operand" may be used to *change*
  20     the behaviour of the pipeline.  In RISC-V terminology it would
  21     typically be set to e.g. funct7 or parts thereof.
  22
  23     """
  24
  25     def __init__(self, width, id_width, op_wid=0, opkls=None,
  26                        pipekls=None, n_ops=2):
  27         """ Create a PipelineSpec. """
  28         self.width = width
  29         self.id_wid = id_width
  30         self.op_wid = op_wid
  31         self.opkls = opkls
  32         self.pipekls = pipekls or SimpleHandshakeRedir
  33         self.n_ops = n_ops
  34         self.stage = None
  35         self.core_config = None
  36         self.fpformat = None
  37         self.n_comb_stages = None
  38