Files
cocotbext-eth/cocotbext/eth/gmii.py
2021-12-03 19:06:43 -08:00

548 lines
18 KiB
Python

"""
Copyright (c) 2020 Alex Forencich
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
"""
import logging
import struct
import zlib
import cocotb
from cocotb.queue import Queue, QueueFull
from cocotb.triggers import RisingEdge, Timer, First, Event
from cocotb.utils import get_sim_time, get_sim_steps
from .version import __version__
from .constants import EthPre, ETH_PREAMBLE
from .reset import Reset
class GmiiFrame:
def __init__(self, data=None, error=None, tx_complete=None):
self.data = bytearray()
self.error = None
self.sim_time_start = None
self.sim_time_sfd = None
self.sim_time_end = None
self.tx_complete = None
if type(data) is GmiiFrame:
self.data = bytearray(data.data)
self.error = data.error
self.sim_time_start = data.sim_time_start
self.sim_time_sfd = data.sim_time_sfd
self.sim_time_end = data.sim_time_end
self.tx_complete = data.tx_complete
else:
self.data = bytearray(data)
self.error = error
if tx_complete is not None:
self.tx_complete = tx_complete
@classmethod
def from_payload(cls, payload, min_len=60, tx_complete=None):
payload = bytearray(payload)
if len(payload) < min_len:
payload.extend(bytearray(min_len-len(payload)))
payload.extend(struct.pack('<L', zlib.crc32(payload)))
return cls.from_raw_payload(payload, tx_complete=tx_complete)
@classmethod
def from_raw_payload(cls, payload, tx_complete=None):
data = bytearray(ETH_PREAMBLE)
data.extend(payload)
return cls(data, tx_complete=tx_complete)
def get_preamble_len(self):
return self.data.index(EthPre.SFD)+1
def get_preamble(self):
return self.data[0:self.get_preamble_len()]
def get_payload(self, strip_fcs=True):
if strip_fcs:
return self.data[self.get_preamble_len():-4]
else:
return self.data[self.get_preamble_len():]
def get_fcs(self):
return self.data[-4:]
def check_fcs(self):
return self.get_fcs() == struct.pack('<L', zlib.crc32(self.get_payload(strip_fcs=True)))
def normalize(self):
n = len(self.data)
if self.error is not None:
self.error = self.error[:n] + [self.error[-1]]*(n-len(self.error))
else:
self.error = [0]*n
def compact(self):
if self.error is not None and not any(self.error):
self.error = None
def handle_tx_complete(self):
if isinstance(self.tx_complete, Event):
self.tx_complete.set(self)
elif callable(self.tx_complete):
self.tx_complete(self)
def __eq__(self, other):
if type(other) is GmiiFrame:
return self.data == other.data
def __repr__(self):
return (
f"{type(self).__name__}(data={self.data!r}, "
f"error={self.error!r}, "
f"sim_time_start={self.sim_time_start!r}, "
f"sim_time_sfd={self.sim_time_sfd!r}, "
f"sim_time_end={self.sim_time_end!r})"
)
def __len__(self):
return len(self.data)
def __iter__(self):
return self.data.__iter__()
def __bytes__(self):
return bytes(self.data)
class GmiiSource(Reset):
def __init__(self, data, er, dv, clock, reset=None, enable=None, mii_select=None, reset_active_level=True, *args, **kwargs):
self.log = logging.getLogger(f"cocotb.{data._path}")
self.data = data
self.er = er
self.dv = dv
self.clock = clock
self.reset = reset
self.enable = enable
self.mii_select = mii_select
self.log.info("GMII source")
self.log.info("cocotbext-eth version %s", __version__)
self.log.info("Copyright (c) 2020 Alex Forencich")
self.log.info("https://github.com/alexforencich/cocotbext-eth")
super().__init__(*args, **kwargs)
self.active = False
self.queue = Queue()
self.dequeue_event = Event()
self.current_frame = None
self.idle_event = Event()
self.idle_event.set()
self.ifg = 12
self.mii_mode = False
self.queue_occupancy_bytes = 0
self.queue_occupancy_frames = 0
self.queue_occupancy_limit_bytes = -1
self.queue_occupancy_limit_frames = -1
self.width = 8
self.byte_width = 1
assert len(self.data) == 8
self.data.setimmediatevalue(0)
if self.er is not None:
assert len(self.er) == 1
self.er.setimmediatevalue(0)
assert len(self.dv) == 1
self.dv.setimmediatevalue(0)
self._run_cr = None
self._init_reset(reset, reset_active_level)
async def send(self, frame):
while self.full():
self.dequeue_event.clear()
await self.dequeue_event.wait()
frame = GmiiFrame(frame)
await self.queue.put(frame)
self.idle_event.clear()
self.queue_occupancy_bytes += len(frame)
self.queue_occupancy_frames += 1
def send_nowait(self, frame):
if self.full():
raise QueueFull()
frame = GmiiFrame(frame)
self.queue.put_nowait(frame)
self.idle_event.clear()
self.queue_occupancy_bytes += len(frame)
self.queue_occupancy_frames += 1
def count(self):
return self.queue.qsize()
def empty(self):
return self.queue.empty()
def full(self):
if self.queue_occupancy_limit_bytes > 0 and self.queue_occupancy_bytes > self.queue_occupancy_limit_bytes:
return True
elif self.queue_occupancy_limit_frames > 0 and self.queue_occupancy_frames > self.queue_occupancy_limit_frames:
return True
else:
return False
def idle(self):
return self.empty() and not self.active
def clear(self):
while not self.queue.empty():
frame = self.queue.get_nowait()
frame.sim_time_end = None
frame.handle_tx_complete()
self.dequeue_event.set()
self.idle_event.set()
self.queue_occupancy_bytes = 0
self.queue_occupancy_frames = 0
async def wait(self):
await self.idle_event.wait()
def _handle_reset(self, state):
if state:
self.log.info("Reset asserted")
if self._run_cr is not None:
self._run_cr.kill()
self._run_cr = None
self.active = False
self.data.value = 0
if self.er is not None:
self.er.value = 0
self.dv.value = 0
if self.current_frame:
self.log.warning("Flushed transmit frame during reset: %s", self.current_frame)
self.current_frame.handle_tx_complete()
self.current_frame = None
if self.queue.empty():
self.idle_event.set()
else:
self.log.info("Reset de-asserted")
if self._run_cr is None:
self._run_cr = cocotb.fork(self._run())
async def _run(self):
frame = None
frame_offset = 0
frame_data = None
frame_error = None
ifg_cnt = 0
self.active = False
clock_edge_event = RisingEdge(self.clock)
while True:
await clock_edge_event
if self.enable is None or self.enable.value:
if ifg_cnt > 0:
# in IFG
ifg_cnt -= 1
elif frame is None and not self.queue.empty():
# send frame
frame = self.queue.get_nowait()
self.dequeue_event.set()
self.queue_occupancy_bytes -= len(frame)
self.queue_occupancy_frames -= 1
self.current_frame = frame
frame.sim_time_start = get_sim_time()
frame.sim_time_sfd = None
frame.sim_time_end = None
self.log.info("TX frame: %s", frame)
frame.normalize()
if self.mii_select is not None:
self.mii_mode = bool(self.mii_select.value.integer)
if self.mii_mode:
# convert to MII
frame_data = []
frame_error = []
for b, e in zip(frame.data, frame.error):
frame_data.append(b & 0x0F)
frame_data.append(b >> 4)
frame_error.append(e)
frame_error.append(e)
else:
frame_data = frame.data
frame_error = frame.error
self.active = True
frame_offset = 0
if frame is not None:
d = frame_data[frame_offset]
if frame.sim_time_sfd is None and d in (EthPre.SFD, 0xD):
frame.sim_time_sfd = get_sim_time()
self.data.value = d
if self.er is not None:
self.er.value = frame_error[frame_offset]
self.dv.value = 1
frame_offset += 1
if frame_offset >= len(frame_data):
ifg_cnt = max(self.ifg, 1)
frame.sim_time_end = get_sim_time()
frame.handle_tx_complete()
frame = None
self.current_frame = None
else:
self.data.value = 0
if self.er is not None:
self.er.value = 0
self.dv.value = 0
self.active = False
self.idle_event.set()
class GmiiSink(Reset):
def __init__(self, data, er, dv, clock, reset=None, enable=None, mii_select=None, reset_active_level=True, *args, **kwargs):
self.log = logging.getLogger(f"cocotb.{data._path}")
self.data = data
self.er = er
self.dv = dv
self.clock = clock
self.reset = reset
self.enable = enable
self.mii_select = mii_select
self.log.info("GMII sink")
self.log.info("cocotbext-eth version %s", __version__)
self.log.info("Copyright (c) 2020 Alex Forencich")
self.log.info("https://github.com/alexforencich/cocotbext-eth")
super().__init__(*args, **kwargs)
self.active = False
self.queue = Queue()
self.active_event = Event()
self.mii_mode = False
self.queue_occupancy_bytes = 0
self.queue_occupancy_frames = 0
self.width = 8
self.byte_width = 1
assert len(self.data) == 8
if self.er is not None:
assert len(self.er) == 1
if self.dv is not None:
assert len(self.dv) == 1
self._run_cr = None
self._init_reset(reset, reset_active_level)
def _recv(self, frame, compact=True):
if self.queue.empty():
self.active_event.clear()
self.queue_occupancy_bytes -= len(frame)
self.queue_occupancy_frames -= 1
if compact:
frame.compact()
return frame
async def recv(self, compact=True):
frame = await self.queue.get()
return self._recv(frame, compact)
def recv_nowait(self, compact=True):
frame = self.queue.get_nowait()
return self._recv(frame, compact)
def count(self):
return self.queue.qsize()
def empty(self):
return self.queue.empty()
def idle(self):
return not self.active
def clear(self):
while not self.queue.empty():
self.queue.get_nowait()
self.active_event.clear()
self.queue_occupancy_bytes = 0
self.queue_occupancy_frames = 0
async def wait(self, timeout=0, timeout_unit=None):
if not self.empty():
return
if timeout:
await First(self.active_event.wait(), Timer(timeout, timeout_unit))
else:
await self.active_event.wait()
def _handle_reset(self, state):
if state:
self.log.info("Reset asserted")
if self._run_cr is not None:
self._run_cr.kill()
self._run_cr = None
self.active = False
else:
self.log.info("Reset de-asserted")
if self._run_cr is None:
self._run_cr = cocotb.fork(self._run())
async def _run(self):
frame = None
self.active = False
clock_edge_event = RisingEdge(self.clock)
while True:
await clock_edge_event
if self.enable is None or self.enable.value:
d_val = self.data.value.integer
dv_val = self.dv.value.integer
er_val = 0 if self.er is None else self.er.value.integer
if frame is None:
if dv_val:
# start of frame
frame = GmiiFrame(bytearray(), [])
frame.sim_time_start = get_sim_time()
else:
if not dv_val:
# end of frame
if self.mii_select is not None:
self.mii_mode = bool(self.mii_select.value.integer)
if self.mii_mode:
odd = True
sync = False
b = 0
be = 0
data = bytearray()
error = []
for n, e in zip(frame.data, frame.error):
odd = not odd
b = (n & 0x0F) << 4 | b >> 4
be |= e
if not sync and b == EthPre.SFD:
odd = True
sync = True
if odd:
data.append(b)
error.append(be)
be = 0
frame.data = data
frame.error = error
frame.compact()
frame.sim_time_end = get_sim_time()
self.log.info("RX frame: %s", frame)
self.queue_occupancy_bytes += len(frame)
self.queue_occupancy_frames += 1
self.queue.put_nowait(frame)
self.active_event.set()
frame = None
if frame is not None:
if frame.sim_time_sfd is None and d_val in (EthPre.SFD, 0xD):
frame.sim_time_sfd = get_sim_time()
frame.data.append(d_val)
frame.error.append(er_val)
class GmiiPhy:
def __init__(self, txd, tx_er, tx_en, tx_clk, gtx_clk, rxd, rx_er, rx_dv, rx_clk,
reset=None, reset_active_level=True, speed=1000e6, *args, **kwargs):
self.gtx_clk = gtx_clk
self.tx_clk = tx_clk
self.rx_clk = rx_clk
super().__init__(*args, **kwargs)
self.tx = GmiiSink(txd, tx_er, tx_en, tx_clk, reset, reset_active_level=reset_active_level)
self.rx = GmiiSource(rxd, rx_er, rx_dv, rx_clk, reset_active_level=reset_active_level)
self.rx_clk.setimmediatevalue(0)
self._clock_cr = None
self.set_speed(speed)
def set_speed(self, speed):
if speed in (10e6, 100e6, 1000e6):
self.speed = speed
else:
raise ValueError("Invalid speed selection")
if self._clock_cr is not None:
self._clock_cr.kill()
if self.speed == 1000e6:
self._clock_cr = cocotb.fork(self._run_clocks(8*1e9/self.speed))
self.tx.mii_mode = False
self.rx.mii_mode = False
self.tx.clock = self.gtx_clk
else:
self._clock_cr = cocotb.fork(self._run_clocks(4*1e9/self.speed))
self.tx.mii_mode = True
self.rx.mii_mode = True
self.tx.clock = self.tx_clk
self.tx.assert_reset()
self.rx.assert_reset()
async def _run_clocks(self, period):
half_period = get_sim_steps(period / 2.0, 'ns')
t = Timer(half_period)
while True:
await t
self.rx_clk.value = 1
self.tx_clk.value = 1
await t
self.rx_clk.value = 0
self.tx_clk.value = 0