litex/misoclib/liteeth/test/mac_wishbone_tb.py

from migen.fhdl.std import *
from migen.bus import wishbone
from migen.bus.transactions import *
from migen.sim.generic import run_simulation

from misoclib.liteeth.common import *
from misoclib.liteeth.mac import LiteEthMAC

from misoclib.liteeth.test.common import *
from misoclib.liteeth.test.model import phy, mac

class WishboneMaster:
	def __init__(self, obj):
		self.obj = obj
		self.dat = 0

	def write(self, adr, dat):
		self.obj.cyc = 1
		self.obj.stb = 1
		self.obj.adr = adr
		self.obj.we = 1
		self.obj.sel = 0xF
		self.obj.dat_w = dat
		while self.obj.ack == 0:
			yield
		self.obj.cyc = 0
		self.obj.stb = 0
		yield

	def read(self, adr):
		self.obj.cyc = 1
		self.obj.stb = 1
		self.obj.adr = adr
		self.obj.we = 0
		self.obj.sel = 0xF
		self.obj.dat_w = 0
		while self.obj.ack == 0:
			yield
		self.dat = self.obj.dat_r
		self.obj.cyc = 0
		self.obj.stb = 0
		yield

class SRAMReaderDriver:
	def __init__(self, obj):
		self.obj = obj

	def start(self, slot, length):
		self.obj._slot.storage = slot
		self.obj._length.storage = length
		self.obj._start.re = 1
		yield
		self.obj._start.re = 0
		yield

	def wait_done(self):
		while self.obj.ev.done.pending == 0:
			yield

	def clear_done(self):
		self.obj.ev.done.clear = 1
		yield
		self.obj.ev.done.clear = 0
		yield

class SRAMWriterDriver:
	def __init__(self, obj):
		self.obj = obj

	def wait_available(self):
		while self.obj.ev.available.pending == 0:
			yield

	def clear_available(self):
		self.obj.ev.available.clear = 1
		yield
		self.obj.ev.available.clear = 0
		yield

class TB(Module):
	def __init__(self):
		self.submodules.phy_model = phy.PHY(8, debug=False)
		self.submodules.mac_model = mac.MAC(self.phy_model, debug=False, loopback=True)
		self.submodules.ethmac = LiteEthMAC(phy=self.phy_model, dw=32, interface="wishbone", with_hw_preamble_crc=True)

		# use sys_clk for each clock_domain
		self.clock_domains.cd_eth_rx = ClockDomain()
		self.clock_domains.cd_eth_tx = ClockDomain()
		self.comb += [
			self.cd_eth_rx.clk.eq(ClockSignal()),
			self.cd_eth_rx.rst.eq(ResetSignal()),
			self.cd_eth_tx.clk.eq(ClockSignal()),
			self.cd_eth_tx.rst.eq(ResetSignal()),
		]

	def gen_simulation(self, selfp):
		selfp.cd_eth_rx.rst = 1
		selfp.cd_eth_tx.rst = 1
		yield
		selfp.cd_eth_rx.rst = 0
		selfp.cd_eth_tx.rst = 0

		wishbone_master = WishboneMaster(selfp.ethmac.bus)
		sram_reader_driver = SRAMReaderDriver(selfp.ethmac.interface.sram.reader)
		sram_writer_driver = SRAMWriterDriver(selfp.ethmac.interface.sram.writer)

		sram_writer_slots_offset = [0x000, 0x200]
		sram_reader_slots_offset = [0x400, 0x600]

		length = 150+2

		tx_payload = [seed_to_data(i, True) % 0xFF for i in range(length)] + [0, 0, 0, 0]

		errors = 0

		while True:
			for slot in range(2):
				print("slot {}: ".format(slot), end="")
				# fill tx memory
				for i in range(length//4+1):
					dat = int.from_bytes(tx_payload[4*i:4*(i+1)], "big")
					yield from wishbone_master.write(sram_reader_slots_offset[slot]+i, dat)

				# send tx payload & wait
				yield from sram_reader_driver.start(slot, length)
				yield from sram_reader_driver.wait_done()
				yield from sram_reader_driver.clear_done()

				# wait rx
				yield from sram_writer_driver.wait_available()
				yield from sram_writer_driver.clear_available()

				# get rx payload (loopback on PHY Model)
				rx_payload = []
				for i in range(length//4+1):
					yield from wishbone_master.read(sram_writer_slots_offset[slot]+i)
					dat = wishbone_master.dat
					rx_payload += list(dat.to_bytes(4, byteorder='big'))

				# check results
				s, l, e = check(tx_payload[:length], rx_payload[:min(length, len(rx_payload))])
				print("shift "+ str(s) + " / length " + str(l) + " / errors " + str(e))

if __name__ == "__main__":
	run_simulation(TB(), ncycles=3000, vcd_name="my.vcd", keep_files=True)