litex/misoclib/com/liteusb/test/ft245_async_tb.py

139 lines
4.4 KiB
Python

from migen.fhdl.std import *
from migen.flow.actor import *
from migen.fhdl.specials import *
from migen.sim.generic import run_simulation
from misoclib.com.liteusb.common import *
from misoclib.com.liteusb.phy.ft245 import FT245PHYAsynchronous
from misoclib.com.liteusb.test.common import *
# XXX for now use it from liteeth to avoid duplication
from misoclib.com.liteeth.test.common import *
class FT245AsynchronousModel(Module):
def __init__(self, clk_freq, rd_data):
self.clk_freq = clk_freq
self.rd_data = [0] + rd_data
self.rd_idx = 0
# timings
self.tRDInactive = self.ns(49) # RXF# inactive after RD# cycle
self.tWRInactive = self.ns(49) # TXE# inactive after WR# cycle
# pads
self.data = Signal(8)
self.rxf_n = Signal(reset=1)
self.txe_n = Signal(reset=1)
self.rd_n = Signal(reset=1)
self.wr_n = Signal(reset=1)
self.init = True
self.wr_data = []
self.wait_wr_n = False
self.rd_done = 0
self.data_w = Signal(8)
self.data_r = Signal(8)
self.specials += Tristate(self.data, self.data_r, ~self.rd_n, self.data_w)
self.last_wr_n = 1
self.last_rd_n = 1
self.wr_delay = 0
self.rd_delay = 0
def wr_sim(self, selfp):
if self.wr_delay:
selfp.txe_n = 1
self.wr_delay = self.wr_delay - 1
else:
if (not selfp.wr_n and self.last_wr_n) and not selfp.txe_n:
self.wr_data.append(selfp.data_w)
self.wr_delay = self.tWRInactive
self.last_wr_n = selfp.wr_n
selfp.txe_n = 0
def rd_sim(self, selfp):
if self.rd_delay:
selfp.rxf_n = 1
self.rd_delay = self.rd_delay - 1
else:
rxf_n = selfp.rxf_n
if self.rd_idx < len(self.rd_data)-1:
self.rd_done = selfp.rxf_n
selfp.rxf_n = 0
else:
selfp.rxf_n = self.rd_done
if not selfp.rd_n and self.last_rd_n:
if self.rd_idx < len(self.rd_data)-1:
self.rd_idx += not rxf_n
selfp.data_r = self.rd_data[self.rd_idx]
self.rd_done = 1
if selfp.rd_n and not self.last_rd_n:
self.rd_delay = self.tRDInactive
self.last_rd_n = selfp.rd_n
def do_simulation(self, selfp):
if self.init:
selfp.rxf_n = 0
self.wr_data = []
self.init = False
self.wr_sim(selfp)
self.rd_sim(selfp)
def ns(self, t, margin=True):
clk_period_ns = 1000000000/self.clk_freq
if margin:
t += clk_period_ns/2
return math.ceil(t/clk_period_ns)
test_packet = [i%256 for i in range(128)]
class TB(Module):
def __init__(self):
clk_freq = 50*1000000
self.submodules.model = FT245AsynchronousModel(clk_freq, test_packet)
self.submodules.phy = FT245PHYAsynchronous(self.model, clk_freq)
self.submodules.streamer = PacketStreamer(phy_description(8))
self.submodules.streamer_randomizer = AckRandomizer(phy_description(8), level=10)
self.submodules.logger_randomizer = AckRandomizer(phy_description(8), level=10)
self.submodules.logger = PacketLogger(phy_description(8))
self.comb += [
Record.connect(self.streamer.source, self.streamer_randomizer.sink),
self.phy.sink.stb.eq(self.streamer_randomizer.source.stb),
self.phy.sink.data.eq(self.streamer_randomizer.source.data),
self.streamer_randomizer.source.ack.eq(self.phy.sink.ack),
self.logger_randomizer.sink.stb.eq(self.phy.source.stb),
self.logger_randomizer.sink.data.eq(self.phy.source.data),
self.phy.source.ack.eq(self.logger_randomizer.sink.ack),
Record.connect(self.logger_randomizer.source, self.logger.sink)
]
def gen_simulation(self, selfp):
yield from self.streamer.send(Packet(test_packet))
for i in range(4000):
yield
s, l, e = check(test_packet, self.model.wr_data)
print("shift " + str(s) + " / length " + str(l) + " / errors " + str(e))
s, l, e = check(test_packet, self.logger.packet)
print("shift " + str(s) + " / length " + str(l) + " / errors " + str(e))
def main():
run_simulation(TB(), ncycles=8000, vcd_name="my.vcd", keep_files=True)
if __name__ == "__main__":
main()