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
  10
  11 class DivStagesStart(PipeModBaseChain):
  12     def get_chain(self):
  13         alu_input = DivMulInputStage(self.pspec)
  14         div_setup = DivSetupStage(self.pspec)
  15         core_setup = DivCoreSetupStage(self.pspec)
  16         return [alu_input, div_setup, core_setup]
  17
  18
  19 class DivStagesMiddle(PipeModBaseChain):
  20     def __init__(self, pspec, stage_start_index, stage_end_index):
  21         self.stage_start_index = stage_start_index
  22         self.stage_end_index = stage_end_index
  23         super().__init__(pspec)
  24
  25     def get_chain(self):
  26         stages = []
  27         for index in range(self.stage_start_index, self.stage_end_index):
  28             stages.append(DivCoreCalculateStage(self.pspec, index))
  29         return stages
  30
  31
  32 class DivStagesEnd(PipeModBaseChain):
  33     def get_chain(self):
  34         core_final = DivCoreFinalStage(self.pspec)
  35         div_out = DivOutputStage(self.pspec)
  36         alu_out = DivMulOutputStage(self.pspec)
  37         self.div_out = div_out  # debugging - bug #425
  38         return [core_final, div_out, alu_out]
  39
  40
  41 class DivBasePipe(ControlBase):
  42     def __init__(self, pspec, compute_steps_per_stage=4):
  43         ControlBase.__init__(self)
  44         self.pspec = pspec
  45         self.pipe_start = DivStagesStart(pspec)
  46         compute_steps = pspec.core_config.n_stages
  47         self.pipe_middles = []
  48         for start in range(0, compute_steps, compute_steps_per_stage):
  49             end = min(start + compute_steps_per_stage, compute_steps)
  50             self.pipe_middles.append(DivStagesMiddle(pspec, start, end))
  51         self.pipe_end = DivStagesEnd(pspec)
  52         self._eqs = self.connect([self.pipe_start,
  53                                   *self.pipe_middles,
  54                                   self.pipe_end])
  55
  56     def elaborate(self, platform):
  57         m = ControlBase.elaborate(self, platform)
  58         m.submodules.pipe_start = self.pipe_start
  59         for i in self.pipe_middles:
  60             name = f"pipe_{i.stage_start_index}_to_{i.stage_end_index}"
  61             setattr(m.submodules, name, i)
  62         m.submodules.pipe_end = self.pipe_end
  63         m.d.comb += self._eqs
  64         return m