litedram/test/test_timing_controllers.py

80 lines
2.2 KiB
Python

# This file is Copyright (c) 2019 Florent Kermarrec <florent@enjoy-digital.fr>
# License: BSD
import unittest
import random
from migen import *
from litedram.common import tXXDController
def c2bool(c):
return {"-": 1, "_": 0}[c]
class TestTimingControllers(unittest.TestCase):
def txxd_controller_test(self, txxd, valids, readys):
def generator(dut):
dut.errors = 0
for valid, ready in zip(valids, readys):
yield dut.valid.eq(c2bool(valid))
yield
if (yield dut.ready) != c2bool(ready):
dut.errors += 1
dut = tXXDController(txxd)
run_simulation(dut, [generator(dut)])
self.assertEqual(dut.errors, 0)
def test_txxd_controller(self):
txxd = 1
valids = "_-______"
readys = "--------"
self.txxd_controller_test(txxd, valids, readys)
txxd = 2
valids = "_-______"
readys = "--_-----"
self.txxd_controller_test(txxd, valids, readys)
txxd = 3
valids = "_-______"
readys = "--__----"
self.txxd_controller_test(txxd, valids, readys)
txxd = 4
valids = "_-______"
readys = "--___---"
self.txxd_controller_test(txxd, valids, readys)
def txxd_controller_random_test(self, txxd, loops):
def generator(dut, valid_rand):
prng = random.Random(42)
for l in range(loops):
while prng.randrange(100) < valid_rand:
yield
yield dut.valid.eq(1)
yield
yield dut.valid.eq(0)
@passive
def checker(dut):
dut.ready_gaps = []
while True:
while (yield dut.ready) != 0:
yield
ready_gap = 1
while (yield dut.ready) != 1:
ready_gap += 1
yield
dut.ready_gaps.append(ready_gap)
dut = tXXDController(txxd)
run_simulation(dut, [generator(dut, valid_rand=90), checker(dut)])
self.assertEqual(min(dut.ready_gaps), txxd)
def test_txxd_controller_random(self):
for i in range(2, 32):
self.txxd_controller_random_test(i, 512)