litex/migen/flow/plumbing.py

56 lines
1.8 KiB
Python

from migen.fhdl.structure import *
from migen.flow.actor import *
from migen.corelogic.record import *
from migen.corelogic.misc import optree
class Buffer(PipelinedActor):
def __init__(self, layout):
super().__init__(1,
("d", Sink, layout), ("q", Source, layout))
def get_process_fragment(self):
sigs_d = self.token("d").flatten()
sigs_q = self.token("q").flatten()
sync = [If(self.pipe_ce, Cat(*sigs_q).eq(Cat(*sigs_d)))]
return Fragment(sync=sync)
class Combinator(CombinatorialActor):
def __init__(self, layout, subrecords):
source = Record(layout)
subrecords = [source.subrecord(*subr) for subr in subrecords]
eps = [("sink{0}".format(n), Sink, r)
for n, r in enumerate(subrecords)]
ep_source = ("source", Source, source)
eps.append(ep_source)
super().__init__(*eps)
def get_fragment(self):
source = self.endpoints["source"]
sinks = [self.endpoints["sink{0}".format(n)]
for n in range(len(self.endpoints)-1)]
comb = [source.stb.eq(optree("&", [sink.stb for sink in sinks]))]
comb += [sink.ack.eq(source.ack & source.stb) for sink in sinks]
return Fragment(comb)
class Splitter(CombinatorialActor):
def __init__(self, layout, subrecords):
sink = Record(layout)
subrecords = [sink.subrecord(*subr) for subr in subrecords]
eps = [("source{0}".format(n), Source, r)
for n, r in enumerate(subrecords)]
ep_sink = ("sink", Sink, sink)
eps.append(ep_sink)
super().__init__(*eps)
# TODO def get_fragment(self):
class Distributor:
pass # TODO
# Actors whose layout should be inferred from what their single sink is connected to.
layout_sink = {Buffer, Splitter, Distributor}
# Actors whose layout should be inferred from what their single source is connected to.
layout_source = {Buffer, Combinator}
# All actors.
actors = layout_sink | layout_source