test/test_gearbox.py

   1 import unittest
   2 import random
   3
   4 from migen import *
   5
   6 from litex.soc.interconnect.stream import Gearbox
   7
   8
   9 def data_generator(dut, gearbox, datas):
  10     prng = random.Random(42)
  11     for i, data in enumerate(datas):
  12         while prng.randrange(4):
  13             yield
  14         yield gearbox.sink.valid.eq(1)
  15         yield gearbox.sink.data.eq(data)
  16         yield
  17         while (yield gearbox.sink.ready) == 0:
  18             yield
  19         yield gearbox.sink.valid.eq(0)
  20
  21
  22 def data_checker(dut, gearbox, datas):
  23         prng = random.Random(42)
  24         dut.errors = 0
  25         for i, reference in enumerate(datas):
  26             yield gearbox.source.ready.eq(1)
  27             yield
  28             while (yield gearbox.source.valid) == 0:
  29                 yield
  30             data =  (yield gearbox.source.data)
  31             if data != reference:
  32                 dut.errors += 1
  33             yield gearbox.source.ready.eq(0)
  34             while prng.randrange(4):
  35                 yield
  36
  37
  38 class GearboxDUT(Module):
  39     def __init__(self):
  40         self.submodules.gearbox0 = Gearbox(20, 32)
  41         self.submodules.gearbox1 = Gearbox(32, 20)
  42         self.comb += self.gearbox0.source.connect(self.gearbox1.sink)
  43
  44
  45 class TestGearbox(unittest.TestCase):
  46     def test_gearbox(self):
  47         prng = random.Random(42)
  48         dut = GearboxDUT()
  49         datas = [prng.randrange(2**20) for i in range(128)]
  50         generators = [
  51             data_generator(dut, dut.gearbox0, datas),
  52             data_checker(dut, dut.gearbox1, datas)
  53         ]
  54         run_simulation(dut, generators, vcd_name="sim.vcd")
  55         self.assertEqual(dut.errors, 0)