src/soc/fu/div/pipeline.py

   1 from nmutil.singlepipe import ControlBase
   2 from nmutil.pipemodbase import PipeModBaseChain
   3 from soc.fu.mul.output_stage import DivMulOutputStage
   4 from soc.fu.div.input_stage import DivMulInputStage
   5 from soc.fu.div.output_stage import DivOutputStage
   6 from soc.fu.div.setup_stage import DivSetupStage
   7 from soc.fu.div.core_stages import (DivCoreSetupStage, DivCoreCalculateStage,
   8                                     DivCoreFinalStage)
   9 from soc.fu.div.pipe_data import DivPipeKindConfigCombPipe
  10
  11
  12 class DivStagesStart(PipeModBaseChain):
  13     def get_chain(self):
  14         alu_input = DivMulInputStage(self.pspec)
  15         return [alu_input]
  16
  17
  18 class DivStagesSetup(PipeModBaseChain):
  19     def get_chain(self):
  20         div_setup = DivSetupStage(self.pspec)
  21         if isinstance(self.pspec.div_pipe_kind.config,
  22                       DivPipeKindConfigCombPipe):
  23             core_setup = [DivCoreSetupStage(self.pspec)]
  24         else:
  25             core_setup = ()
  26         return [div_setup, *core_setup]
  27
  28
  29 class DivStagesMiddle(PipeModBaseChain):
  30     def __init__(self, pspec, stage_start_index, stage_end_index):
  31         assert isinstance(pspec.div_pipe_kind.config,
  32                           DivPipeKindConfigCombPipe),\
  33             "DivStagesMiddle must be used with a DivPipeKindConfigCombPipe"
  34         self.stage_start_index = stage_start_index
  35         self.stage_end_index = stage_end_index
  36         super().__init__(pspec)
  37
  38     def get_chain(self):
  39         stages = []
  40         for index in range(self.stage_start_index, self.stage_end_index):
  41             stages.append(DivCoreCalculateStage(self.pspec, index))
  42         return stages
  43
  44
  45 class DivStagesEnd(PipeModBaseChain):
  46     def get_chain(self):
  47         if isinstance(self.pspec.div_pipe_kind.config,
  48                       DivPipeKindConfigCombPipe):
  49             core_final = [DivCoreFinalStage(self.pspec)]
  50         else:
  51             core_final = ()
  52         div_out = DivOutputStage(self.pspec)
  53         self.div_out = div_out  # debugging - bug #425
  54         return [*core_final, div_out]
  55
  56
  57 class DivStagesFinalise(PipeModBaseChain):
  58     def get_chain(self):
  59         alu_out = DivMulOutputStage(self.pspec)
  60         return [alu_out]
  61
  62
  63 class DivBasePipe(ControlBase):
  64     def __init__(self, pspec, compute_steps_per_stage=4):
  65         ControlBase.__init__(self)
  66         self.pspec = pspec
  67         self.pipe_start = DivStagesStart(pspec)
  68         self.pipe_setup = DivStagesSetup(pspec)
  69         self.pipe_middles = []
  70         if isinstance(self.pspec.div_pipe_kind.config,
  71                       DivPipeKindConfigCombPipe):
  72             compute_steps = pspec.core_config.n_stages
  73             for start in range(0, compute_steps, compute_steps_per_stage):
  74                 end = min(start + compute_steps_per_stage, compute_steps)
  75                 self.pipe_middles.append(DivStagesMiddle(pspec, start, end))
  76         else:
  77             self.pipe_middles.append(
  78                 self.pspec.div_pipe_kind.config.core_stage_class(pspec))
  79         self.pipe_end = DivStagesEnd(pspec)
  80         self.pipe_final = DivStagesFinalise(pspec)
  81         self._eqs = self.connect([self.pipe_start,
  82                                   self.pipe_setup,
  83                                   *self.pipe_middles,
  84                                   self.pipe_end,
  85                                   self.pipe_final])
  86
  87     def elaborate(self, platform):
  88         m = ControlBase.elaborate(self, platform)
  89         m.submodules.pipe_start = self.pipe_start
  90         m.submodules.pipe_setup = self.pipe_setup
  91         for i in range(len(self.pipe_middles)):
  92             name = f"pipe_middle_{i}"
  93             setattr(m.submodules, name, self.pipe_middles[i])
  94         m.submodules.pipe_end = self.pipe_end
  95         m.submodules.pipe_final = self.pipe_final
  96         m.d.comb += self._eqs
  97         return m