litex/misoc/dvisampler/chansync.py

133 lines
3.9 KiB
Python

from migen import *
from migen.genlib.cdc import MultiReg
from migen.genlib.fifo import _inc
from migen.genlib.record import Record, layout_len
from migen.genlib.misc import optree
from migen.bank.description import *
from misoc.dvisampler.common import channel_layout
class _SyncBuffer(Module):
def __init__(self, width, depth):
self.din = Signal(width)
self.dout = Signal(width)
self.re = Signal()
###
produce = Signal(max=depth)
consume = Signal(max=depth)
storage = Memory(width, depth)
self.specials += storage
wrport = storage.get_port(write_capable=True)
self.specials += wrport
self.comb += [
wrport.adr.eq(produce),
wrport.dat_w.eq(self.din),
wrport.we.eq(1)
]
self.sync += _inc(produce, depth)
rdport = storage.get_port(async_read=True)
self.specials += rdport
self.comb += [
rdport.adr.eq(consume),
self.dout.eq(rdport.dat_r)
]
self.sync += If(self.re, _inc(consume, depth))
class ChanSync(Module, AutoCSR):
def __init__(self, nchan=3, depth=8):
self.valid_i = Signal()
self.chan_synced = Signal()
self._channels_synced = CSRStatus()
lst_control = []
all_control = Signal()
for i in range(nchan):
name = "data_in" + str(i)
data_in = Record(channel_layout, name=name)
setattr(self, name, data_in)
name = "data_out" + str(i)
data_out = Record(channel_layout, name=name)
setattr(self, name, data_out)
###
syncbuffer = RenameClockDomains(_SyncBuffer(layout_len(channel_layout), depth), "pix")
self.submodules += syncbuffer
self.comb += [
syncbuffer.din.eq(data_in.raw_bits()),
data_out.raw_bits().eq(syncbuffer.dout)
]
is_control = Signal()
self.comb += [
is_control.eq(~data_out.de),
syncbuffer.re.eq(~is_control | all_control)
]
lst_control.append(is_control)
some_control = Signal()
self.comb += [
all_control.eq(optree("&", lst_control)),
some_control.eq(optree("|", lst_control))
]
self.sync.pix += If(~self.valid_i,
self.chan_synced.eq(0)
).Else(
If(some_control,
If(all_control,
self.chan_synced.eq(1)
).Else(
self.chan_synced.eq(0)
)
)
)
self.specials += MultiReg(self.chan_synced, self._channels_synced.status)
class _TB(Module):
def __init__(self, test_seq_it):
self.test_seq_it = test_seq_it
self.submodules.chansync = RenameClockDomains(ChanSync(), {"pix": "sys"})
self.comb += self.chansync.valid_i.eq(1)
def do_simulation(self, selfp):
try:
de0, de1, de2 = next(self.test_seq_it)
except StopIteration:
raise StopSimulation
selfp.chansync.data_in0.de = de0
selfp.chansync.data_in1.de = de1
selfp.chansync.data_in2.de = de2
selfp.chansync.data_in0.d = selfp.simulator.cycle_counter
selfp.chansync.data_in1.d = selfp.simulator.cycle_counter
selfp.chansync.data_in2.d = selfp.simulator.cycle_counter
out0 = selfp.chansync.data_out0.d
out1 = selfp.chansync.data_out1.d
out2 = selfp.chansync.data_out2.d
print("{0:5} {1:5} {2:5}".format(out0, out1, out2))
if __name__ == "__main__":
from migen.sim.generic import run_simulation
test_seq = [
(1, 1, 1),
(1, 1, 0),
(0, 0, 0),
(0, 0, 0),
(0, 0, 1),
(1, 1, 1),
(1, 1, 1),
]
tb = _TB(iter(test_seq*2))
run_simulation(tb)