litedram/test/test_refresh.py

68 lines
2.2 KiB
Python

# This file is Copyright (c) 2019 Florent Kermarrec <florent@enjoy-digital.fr>
# License: BSD
import unittest
from migen import *
from litedram.core.multiplexer import cmd_request_rw_layout
from litedram.core.refresher import RefreshGenerator, RefreshTimer
def c2bool(c):
return {"-": 1, "_": 0}[c]
class TestRefresh(unittest.TestCase):
def refresh_generator_test(self, trp, trfc, starts, dones, cmds):
cmd = Record(cmd_request_rw_layout(a=16, ba=3))
def generator(dut):
dut.errors = 0
for start, done, cas, ras in zip(starts, dones, cmds.cas, cmds.ras):
yield dut.start.eq(c2bool(start))
yield
if (yield dut.done) != c2bool(done):
dut.errors += 1
if (yield cmd.cas) != c2bool(cas):
dut.errors += 1
if (yield cmd.ras) != c2bool(ras):
dut.errors += 1
dut = RefreshGenerator(cmd, trp, trfc)
run_simulation(dut, [generator(dut)])
self.assertEqual(dut.errors, 0)
def test_refresh_generator(self):
trp = 1
trfc = 2
class CMDS: pass
cmds = CMDS()
starts = "_-______________"
cmds.cas = "____-___________"
cmds.ras = "___--___________"
dones = "______-_________"
self.refresh_generator_test(trp, trfc, starts, dones, cmds)
def refresh_timer_test(self, trefi):
def generator(dut):
dut.errors = 0
for i in range(16*(trefi + 1)):
yield
if i%(trefi + 1) == (trefi - 1):
if (yield dut.refresh.done) != 1:
dut.errors += 1
else:
if (yield dut.refresh.done) != 0:
dut.errors += 1
class DUT(Module):
def __init__(self, trefi):
self.submodules.refresh = RefreshTimer(trefi)
self.comb += self.refresh.wait.eq(~self.refresh.done)
dut = DUT(trefi)
run_simulation(dut, [generator(dut)])
self.assertEqual(dut.errors, 0)
def test_refresh_timer(self):
for i in range(1, 32):
self.refresh_timer_test(i)