litex/test/test_axi.py

97 lines
2.9 KiB
Python

import unittest
import random
from migen import *
from litedram.common import *
from litedram.frontend.axi import *
from litex.gen.sim import *
class Burst:
def __init__(self, addr, type=BURST_FIXED, len=0, size=0):
self.addr = addr
self.type = type
self.len = len
self.size = size
def to_beats(self):
r = []
for i in range(self.len + 1):
if self.type == BURST_INCR:
offset = i*2**(self.size)
r += [Beat(self.addr + offset)]
elif self.type == BURST_WRAP:
offset = (i*2**(self.size))%((2**self.size)*(self.len))
r += [Beat(self.addr + offset)]
else:
r += [Beat(self.addr)]
return r
class Beat:
def __init__(self, addr):
self.addr = addr
class TestAXI(unittest.TestCase):
def test_burst2beat(self):
def bursts_generator(ax, bursts, valid_rand=50):
prng = random.Random(42)
for burst in bursts:
yield ax.valid.eq(1)
yield ax.addr.eq(burst.addr)
yield ax.burst.eq(burst.type)
yield ax.len.eq(burst.len)
yield ax.size.eq(burst.size)
while (yield ax.ready) == 0:
yield
yield ax.valid.eq(0)
while prng.randrange(100) < valid_rand:
yield
yield
@passive
def beats_checker(ax, beats, ready_rand=50):
self.errors = 0
yield ax.ready.eq(0)
prng = random.Random(42)
for beat in beats:
while ((yield ax.valid) and (yield ax.ready)) == 0:
if prng.randrange(100) > ready_rand:
yield ax.ready.eq(1)
else:
yield ax.ready.eq(0)
yield
ax_addr = (yield ax.addr)
if ax_addr != beat.addr:
self.errors += 1
yield
# dut
ax_burst = stream.Endpoint(ax_description(32, 32))
ax_beat = stream.Endpoint(ax_description(32, 32))
dut = AXIBurst2Beat(ax_burst, ax_beat)
# generate dut input (bursts)
prng = random.Random(42)
bursts = []
for i in range(32):
bursts.append(Burst(prng.randrange(2**32), BURST_FIXED, prng.randrange(255), log2_int(32//8)))
bursts.append(Burst(prng.randrange(2**32), BURST_INCR, prng.randrange(255), log2_int(32//8)))
bursts.append(Burst(4, BURST_WRAP, 4-1, log2_int(2)))
# generate expected dut output (beats for reference)
beats = []
for burst in bursts:
beats += burst.to_beats()
# simulation
generators = [
bursts_generator(ax_burst, bursts),
beats_checker(ax_beat, beats)
]
run_simulation(dut, generators)
self.assertEqual(self.errors, 0)