rtio-nmigen/rtio/sed/output_driver.py

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2020-10-09 11:16:01 +08:00
from functools import reduce
from operator import or_
2020-10-09 11:16:01 +08:00
from nmigen import *
from rtio.sed import layouts
from rtio.sed.output_network import OutputNetwork
__all__ = ["OutputDriver"]
class OutputDriver(Elaboratable):
def __init__(self, channels, glbl_fine_ts_width, lane_count, seqn_width):
m = Module()
self.m = m
self.collision = Signal()
self.collision_channel = Signal(range(len(channels)), reset_less=True)
self.busy = Signal()
self.busy_channel = Signal(range(len(channels)), reset_less=True)
# output network
layout_on_payload = layouts.output_network_payload(channels, glbl_fine_ts_width)
output_network = OutputNetwork(lane_count, seqn_width, layout_on_payload)
m.submodules += output_network
self.input = output_network.input
# detect collisions (adds one pipeline stage)
layout_lane_data = [
("valid", 1),
("collision", 1),
("payload", layout_on_payload)
]
lane_datas = [Record(layout_lane_data, reset_less=True) for _ in range(lane_count)]
en_replaces = [channel.interface.o.enable_replace for channel in channels]
for lane_data, on_output in zip(lane_datas, output_network.output):
lane_data.valid.reset_less = False
lane_data.collision.reset_less = False
replace_occured_r = Signal()
nondata_replace_occured_r = Signal()
m.d.sync += lane_data.valid.eq(on_output.valid)
m.d.sync += lane_data.payload.eq(on_output.payload)
m.d.sync += replace_occured_r.eq(on_output.replace_occured)
m.d.sync += nondata_replace_occured_r.eq(on_output.nondata_replace_occured)
en_replaces_rom = Memory(width=1, depth=len(en_replaces), init=en_replaces)
en_replaces_rom_port = en_replaces_rom.read_port()
m.submodules += en_replaces_rom_port
m.d.comb += en_replaces_rom_port.addr.eq(on_output.payload.channel)
m.d.comb += lane_data.collision.eq(replace_occured_r & (~en_replaces_rom_port.data | nondata_replace_occured_r))
m.d.sync += self.collision.eq(0)
m.d.sync += self.collision_channel.eq(0)
for lane_data in lane_datas:
with m.If(lane_data.valid & lane_data.collision):
m.d.sync += self.collision.eq(1)
m.d.sync += self.collision_channel.eq(lane_data.payload.channel)
# demultiplex channels (adds one pipeline stage)
for n, channel in enumerate(channels):
oif = channel.interface.o
onehot_stb = []
onehot_fine_ts = []
onehot_address = []
onehot_data = []
for lane_data in lane_datas:
selected = Signal()
m.d.comb += selected.eq(lane_data.valid & ~lane_data.collision & (lane_data.payload.channel == n))
onehot_stb.append(selected)
if hasattr(lane_data.payload, "fine_ts") and hasattr(oif, "fine_ts"):
ts_shift = len(lane_data.ayload.fine_ts) - len(oif.fine_ts)
onehot_fine_ts.append(Mux(selected, lane_data.payload.fine_ts[ts_shift:], 0))
if hasattr(lane_data.payload, "address"):
onehot_address.append(Mux(selected, lane_datapayload.address, 0))
if hasattr(lane_data.payload, "data"):
onehot_data.append(Mux(selected, lane_data.payload.data, 0))
m.d.sync += oif.stb.eq(reduce(or_, onehot_stb))
if hasattr(oif, "fine_ts"):
m.d.sync += oif.fine_ts.eq(reduce(or_, onehot_fine_ts))
if hasattr(oif, "address"):
m.d.sync += oif.address.eq(reduce(or_, onehot_address))
if hasattr(oif, "data"):
m.d.sync += oif.data.eq(reduce(or_, onehot_data))
# detect busy errors, at lane level to reduce mixing
m.d.sync += self.busy.eq(0)
m.d.sync += self.busy_channel.eq(0)
for lane_data in lane_datas:
stb_r = Signal()
channel_r = Signal(range(len(channels)), reset_less=True)
m.d.sync += stb_r.eq(lane_data.valid & ~lane_data.collision)
m.d.sync += channel_r.eq(lane_data.payload.channel)
with m.If(stb_r & Array(channel.interface.o.busy for channel in channels)[channel_r]):
m.d.sync += self.busy.eq(1)
m.d.sync += self.busy_channel.eq(channel_r)
def elaborate(self, platform):
return self.m