artiq/soc/artiqlib/rtio/__init__.py

66 lines
2.0 KiB
Python

from migen.fhdl.std import *
from migen.bank.description import *
from migen.genlib.fifo import SyncFIFOBuffered
from migen.genlib.cdc import MultiReg
class RTIOChannelO(Module):
def __init__(self, signal, counter_width, fifo_depth):
self.submodules.fifo = SyncFIFOBuffered([
("timestamp", counter_width), ("value", 1)],
fifo_depth)
self.event = self.fifo.din
self.writable = self.fifo.writable
self.we = self.fifo.we
self.underflow = Signal()
self.level = self.fifo.level
###
counter = Signal(counter_width)
self.sync += counter.eq(counter + 1)
self.sync += If(self.we & self.writable,
If(self.event.timestamp < counter + 2,
self.underflow.eq(1)
)
)
time_hit = Signal()
self.comb += [
time_hit.eq(self.fifo.readable &
(self.fifo.dout.timestamp == counter)),
self.fifo.re.eq(time_hit)
]
self.sync += If(time_hit, signal.eq(self.fifo.dout.value))
class RTIO(Module, AutoCSR):
def __init__(self, channels, counter_width=32, ofifo_depth=8, ififo_depth=8):
self._r_reset = CSRStorage(reset=1)
self._r_chan_sel = CSRStorage(bits_for(len(channels)-1))
self._r_o_timestamp = CSRStorage(counter_width)
self._r_o_value = CSRStorage()
self._r_o_writable = CSRStatus()
self._r_o_we = CSR()
self._r_o_underflow = CSRStatus()
self._r_o_level = CSRStatus(bits_for(ofifo_depth))
channel_os = []
for n, channel in enumerate(channels):
channel_o = InsertReset(RTIOChannelO(channel, counter_width, ofifo_depth))
self.submodules += channel_o
channel_os.append(channel_o)
self.comb += [
channel_o.reset.eq(self._r_reset.storage),
channel_o.event.timestamp.eq(self._r_o_timestamp.storage),
channel_o.event.value.eq(self._r_o_value.storage),
channel_o.we.eq(self._r_o_we.re & (self._r_chan_sel.storage == n))
]
channel_o = Array(channel_os)[self._r_chan_sel.storage]
self.comb += [
self._r_o_writable.status.eq(channel_o.writable),
self._r_o_underflow.status.eq(channel_o.underflow),
self._r_o_level.status.eq(channel_o.level)
]