litedram/test/test_fifo.py

319 lines
11 KiB
Python

#
# This file is part of LiteDRAM.
#
# Copyright (c) 2019-2021 Florent Kermarrec <florent@enjoy-digital.fr>
# Copyright (c) 2020 Antmicro <www.antmicro.com>
# SPDX-License-Identifier: BSD-2-Clause
import unittest
import random
from migen import *
from litex.soc.interconnect.stream import *
from litedram.common import LiteDRAMNativeWritePort
from litedram.common import LiteDRAMNativeReadPort
from litedram.frontend.fifo import LiteDRAMFIFO, _LiteDRAMFIFOCtrl
from litedram.frontend.fifo import _LiteDRAMFIFOWriter, _LiteDRAMFIFOReader
from test.common import *
class FIFODUT(Module):
def __init__(self, base, depth, data_width=8, address_width=32, with_bypass=False):
self.write_port = LiteDRAMNativeWritePort(address_width=32, data_width=data_width)
self.read_port = LiteDRAMNativeReadPort(address_width=32, data_width=data_width)
self.submodules.fifo = LiteDRAMFIFO(
data_width = data_width,
base = base,
depth = depth,
write_port = self.write_port,
read_port = self.read_port,
with_bypass = with_bypass
)
margin = 8
self.memory = DRAMMemory(data_width, base + depth + margin)
def write(self, data):
yield self.fifo.sink.valid.eq(1)
yield self.fifo.sink.data.eq(data)
yield
while not (yield self.fifo.sink.ready):
yield
yield self.fifo.sink.valid.eq(0)
def read(self):
while not (yield self.fifo.source.valid):
yield
yield self.fifo.source.ready.eq(1)
data = (yield self.fifo.source.data)
yield
yield self.fifo.source.ready.eq(0)
yield
return data
class TestFIFO(unittest.TestCase):
# _LiteDRAMFIFOCtrl ----------------------------------------------------------------------------
def test_fifo_ctrl_address_changes(self):
# Verify FIFOCtrl address changes.
dut = _LiteDRAMFIFOCtrl(base=0, depth=16)
def main_generator():
self.assertEqual((yield dut.write_address), 0)
self.assertEqual((yield dut.read_address), 0)
# Write address
yield dut.write.eq(1)
yield
# Write_address gets updated 1 cycle later
for i in range(24 - 1):
self.assertEqual((yield dut.write_address), i % 16)
yield
yield dut.write.eq(0)
yield
self.assertEqual((yield dut.write_address), 24 % 16)
# Read address
yield dut.read.eq(1)
yield
for i in range(24 - 1):
self.assertEqual((yield dut.read_address), i % 16)
yield
yield dut.read.eq(0)
yield
self.assertEqual((yield dut.read_address), 24 % 16)
run_simulation(dut, main_generator())
def test_fifo_ctrl_level_changes(self):
# Verify FIFOCtrl level changes.
dut = _LiteDRAMFIFOCtrl(base=0, depth=16)
def main_generator():
self.assertEqual((yield dut.level), 0)
def check_level_diff(write, read, diff):
level = (yield dut.level)
yield dut.write.eq(write)
yield dut.read.eq(read)
yield
yield dut.write.eq(0)
yield dut.read.eq(0)
yield
self.assertEqual((yield dut.level), level + diff)
check_level_diff(write=1, read=0, diff=+1)
check_level_diff(write=1, read=0, diff=+1)
check_level_diff(write=1, read=1, diff=+0)
check_level_diff(write=1, read=1, diff=+0)
check_level_diff(write=0, read=1, diff=-1)
check_level_diff(write=0, read=1, diff=-1)
run_simulation(dut, main_generator())
# _LiteDRAMFIFOWriter --------------------------------------------------------------------------
def fifo_writer_test(self, depth, sequence_len, consume=False):
class DUT(Module):
def __init__(self):
self.port = LiteDRAMNativeWritePort(address_width=32, data_width=32)
ctrl = _LiteDRAMFIFOCtrl(base=8, depth=depth)
self.submodules.ctrl = ctrl
writer = _LiteDRAMFIFOWriter(data_width=32, port=self.port, ctrl=ctrl)
self.submodules.writer = writer
self.memory = DRAMMemory(32, 128)
assert 8 + sequence_len <= len(self.memory.mem)
write_data = [seed_to_data(i) for i in range(sequence_len)]
def generator(dut):
for data in write_data:
yield dut.writer.sink.valid.eq(1)
yield dut.writer.sink.data.eq(data)
yield
while (yield dut.writer.sink.ready) == 0:
yield
yield dut.writer.sink.valid.eq(0)
if consume:
yield dut.ctrl.read.eq(1)
for _ in range(16):
yield
dut = DUT()
generators = [
generator(dut),
dut.memory.write_handler(dut.port),
timeout_generator(1500),
]
run_simulation(dut, generators)
mem_expected = [0] * len(dut.memory.mem)
for i, data in enumerate(write_data):
mem_expected[8 + i%depth] = data
self.assertEqual(dut.memory.mem, mem_expected)
def test_fifo_writer_sequence(self):
# Verify simple FIFOWriter sequence.
self.fifo_writer_test(sequence_len=48, depth=64)
def test_fifo_writer_stops_when_full(self):
# Verify FIFOWriter won't continue writing if noone reads the data.
with self.assertRaises(TimeoutError):
self.fifo_writer_test(sequence_len=48, depth=32)
def test_fifo_writer_address_wraps(self):
# Verify FIFOWriter address wraps.
self.fifo_writer_test(sequence_len=48, depth=32, consume=True)
# _LiteDRAMFIFOReader --------------------------------------------------------------------------
def fifo_reader_test(self, depth, sequence_len, inital_writes=0):
memory_data = [seed_to_data(i) for i in range(128)]
read_data = []
class DUT(Module):
def __init__(self):
self.port = LiteDRAMNativeReadPort(address_width=32, data_width=32)
ctrl = _LiteDRAMFIFOCtrl(base=8, depth=depth)
reader = _LiteDRAMFIFOReader(data_width=32, port=self.port, ctrl=ctrl)
self.submodules.ctrl = ctrl
self.submodules.reader = reader
self.memory = DRAMMemory(32, len(memory_data), init=memory_data)
assert 8 + sequence_len <= len(self.memory.mem)
def reader(dut):
# Fake writing to fifo
yield dut.ctrl.write.eq(1)
for _ in range(inital_writes):
yield
yield dut.ctrl.write.eq(0)
yield
for _ in range(sequence_len):
# Fake single write
yield dut.ctrl.write.eq(1)
yield
yield dut.ctrl.write.eq(0)
while (yield dut.reader.source.valid) == 0:
yield
read_data.append((yield dut.reader.source.data))
yield dut.reader.source.ready.eq(1)
yield
yield dut.reader.source.ready.eq(0)
yield
dut = DUT()
generators = [
reader(dut),
dut.memory.read_handler(dut.port),
timeout_generator(1500),
]
run_simulation(dut, generators)
read_data_expected = [memory_data[8 + i%depth] for i in range(sequence_len)]
self.assertEqual(read_data, read_data_expected)
def test_fifo_reader_sequence(self):
# Verify simple FIFOReader sequence.
self.fifo_reader_test(sequence_len=48, depth=64)
def test_fifo_reader_address_wraps(self):
# Verify FIFOReader sequence with address wraps.
self.fifo_reader_test(sequence_len=48, depth=32)
# LiteDRAMFIFO ---------------------------------------------------------------------------------
def fifo_continuous_stream_short_test(self, with_bypass):
# Verify FIFO operation with continuous writes and reads without wrapping
def generator(dut):
for i in range(64):
yield from dut.write(10 + i)
def checker(dut):
for i in range(64):
data = (yield from dut.read())
self.assertEqual(data, 10 + i)
dut = FIFODUT(base=16, depth=128, with_bypass=with_bypass)
generators = [
generator(dut),
checker(dut),
dut.memory.write_handler(dut.write_port),
dut.memory.read_handler(dut.read_port),
timeout_generator(1500),
]
run_simulation(dut, generators)
def test_fifo_continuous_stream_short(self):
self.fifo_continuous_stream_short_test(with_bypass=False)
def test_fifo_continuous_stream_short_with_bypass(self):
self.fifo_continuous_stream_short_test(with_bypass=True)
def fifo_continuous_stream_long_test(self, with_bypass):
# Verify FIFO operation with continuous writes and reads with wrapping
def generator(dut):
for i in range(64):
yield from dut.write(10 + i)
def checker(dut):
for i in range(64):
data = (yield from dut.read())
self.assertEqual(data, 10 + i)
dut = FIFODUT(base=16, depth=32, with_bypass=with_bypass)
generators = [
generator(dut),
checker(dut),
dut.memory.write_handler(dut.write_port),
dut.memory.read_handler(dut.read_port),
timeout_generator(1500),
]
run_simulation(dut, generators)
def test_fifo_continuous_stream_long(self):
self.fifo_continuous_stream_long_test(with_bypass=False)
def test_fifo_continuous_stream_long_with_bypass(self):
self.fifo_continuous_stream_long_test(with_bypass=True)
def fifo_delayed_reader_test(self, with_bypass):
# Verify FIFO works correctly when reader starts reading only after writer is full
def generator(dut):
for i in range(128):
yield from dut.write(10 + i)
def checker(dut):
# Wait until both the internal writer FIFO and our in-memory FIFO are full
while (yield dut.fifo.dram_fifo.ctrl.writable):
yield
for i in range(128):
data = (yield from dut.read())
self.assertEqual(data, 10 + i)
for i in range(32):
yield
dut = FIFODUT(base=16, depth=32, with_bypass=with_bypass)
generators = [
generator(dut),
checker(dut),
dut.memory.write_handler(dut.write_port),
dut.memory.read_handler(dut.read_port),
timeout_generator(1500),
]
run_simulation(dut, generators)
def test_fifo_delayed_reader(self):
self.fifo_delayed_reader_test(with_bypass=False)
def test_fifo_delayed_reader_with_bypass(self):
self.fifo_delayed_reader_test(with_bypass=True)