litedram/test/test_bist.py

87 lines
2.3 KiB
Python
Executable File

import unittest
import random
from litex.gen import *
from litex.soc.interconnect.stream import *
from litedram.common import LiteDRAMWritePort, LiteDRAMReadPort
from litedram.frontend.bist import _LiteDRAMBISTGenerator
from litedram.frontend.bist import _LiteDRAMBISTChecker
from test.common import *
class DUT(Module):
def __init__(self):
self.write_port = LiteDRAMWritePort(aw=32, dw=32)
self.read_port = LiteDRAMReadPort(aw=32, dw=32)
self.submodules.generator = _LiteDRAMBISTGenerator(self.write_port, True)
self.submodules.checker = _LiteDRAMBISTChecker(self.read_port, True)
class BISTDriver:
def __init__(self, module):
self.module = module
def reset(self):
yield self.module.reset.eq(1)
yield
yield self.module.reset.eq(0)
yield
def run(self, base, length):
yield self.module.base.eq(base)
yield self.module.length.eq(length)
yield self.module.start.eq(1)
yield
yield self.module.start.eq(0)
yield
while((yield self.module.done) == 0):
yield
if hasattr(self.module, "errors"):
self.errors = (yield self.module.errors)
def main_generator(dut, mem):
generator = BISTDriver(dut.generator)
checker = BISTDriver(dut.checker)
# write
yield from generator.reset()
yield from generator.run(16, 64)
# read (no errors)
yield from checker.reset()
yield from checker.run(16, 64)
assert checker.errors == 0
# corrupt memory (using generator)
yield from generator.reset()
yield from generator.run(16 + 60, 64)
# read (4 errors)
yield from checker.reset()
yield from checker.run(16, 64)
assert checker.errors == 4
# read (no errors)
yield from checker.reset()
yield from checker.run(16 + 60, 64)
assert checker.errors == 0
class TestBIST(unittest.TestCase):
def test(self):
dut = DUT()
mem = DRAMMemory(32, 128)
generators = {
"sys" : [
main_generator(dut, mem),
mem.write_generator(dut.write_port),
mem.read_generator(dut.read_port)
]
}
clocks = {"sys": 10}
run_simulation(dut, generators, clocks, vcd_name="sim.vcd")