Files
cocotbext-eth/cocotbext/eth/rgmii.py
2021-03-21 12:22:51 -07:00

416 lines
13 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 cocotb
from cocotb.queue import Queue
from cocotb.triggers import RisingEdge, FallingEdge, Timer, First, Event
from cocotb.utils import get_sim_time, get_sim_steps
from .version import __version__
from .gmii import GmiiFrame
from .constants import EthPre
from .reset import Reset
class RgmiiSource(Reset):
def __init__(self, data, ctrl, 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.ctrl = ctrl
self.clock = clock
self.reset = reset
self.enable = enable
self.mii_select = mii_select
self.log.info("RGMII 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.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.width = 8
self.byte_width = 1
assert len(self.data) == 4
self.data.setimmediatevalue(0)
assert len(self.ctrl) == 1
self.ctrl.setimmediatevalue(0)
self._run_cr = None
self._init_reset(reset, reset_active_level)
async def send(self, frame):
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):
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 idle(self):
return self.empty() and not self.active
def clear(self):
while not self.queue.empty():
self.queue.get_nowait()
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
else:
self.log.info("Reset de-asserted")
if self._run_cr is None:
self._run_cr = cocotb.scheduler.start_soon(self._run())
self.active = False
self.data <= 0
self.ctrl <= 0
async def _run(self):
frame = None
ifg_cnt = 0
self.active = False
d = 0
er = 0
en = 0
while True:
await RisingEdge(self.clock)
# send high nibble after rising edge, leading in to falling edge
self.data <= d >> 4
self.ctrl <= en ^ er
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.queue_occupancy_bytes -= len(frame)
self.queue_occupancy_frames -= 1
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:
mii_data = []
mii_error = []
for b, e in zip(frame.data, frame.error):
mii_data.append((b & 0x0F)*0x11)
mii_data.append((b >> 4)*0x11)
mii_error.append(e)
mii_error.append(e)
frame.data = mii_data
frame.error = mii_error
self.active = True
if frame is not None:
d = frame.data.pop(0)
er = frame.error.pop(0)
en = 1
if frame.sim_time_sfd is None and d in (EthPre.SFD, 0xD, 0xDD):
frame.sim_time_sfd = get_sim_time()
if not frame.data:
ifg_cnt = max(self.ifg, 1)
frame.sim_time_end = get_sim_time()
frame.handle_tx_complete()
frame = None
else:
d = 0
er = 0
en = 0
self.active = False
self.idle_event.set()
await FallingEdge(self.clock)
# send low nibble after falling edge, leading in to rising edge
self.data <= d & 0x0F
self.ctrl <= en
class RgmiiSink(Reset):
def __init__(self, data, ctrl, 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.ctrl = ctrl
self.clock = clock
self.reset = reset
self.enable = enable
self.mii_select = mii_select
self.log.info("RGMII 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) == 4
assert len(self.ctrl) == 1
self._run_cr = None
self._init_reset(reset, reset_active_level)
async def recv(self, compact=True):
frame = await self.queue.get()
if self.queue.empty():
self.active_event.clear()
self.queue_occupancy_bytes -= len(frame)
self.queue_occupancy_frames -= 1
return frame
def recv_nowait(self, compact=True):
if not self.queue.empty():
frame = self.queue.get_nowait()
if self.queue.empty():
self.active_event.clear()
self.queue_occupancy_bytes -= len(frame)
self.queue_occupancy_frames -= 1
return frame
return None
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
else:
self.log.info("Reset de-asserted")
if self._run_cr is None:
self._run_cr = cocotb.scheduler.start_soon(self._run())
self.active = False
async def _run(self):
frame = None
self.active = False
d_val = 0
dv_val = 0
er_val = 0
while True:
await RisingEdge(self.clock)
# capture low nibble on rising edge
d_val = self.data.value.integer
dv_val = self.ctrl.value.integer
await FallingEdge(self.clock)
# capture high nibble on falling edge
d_val |= self.data.value.integer << 4
er_val = dv_val ^ self.ctrl.value.integer
if self.enable is None or self.enable.value:
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, 0xDD):
frame.sim_time_sfd = get_sim_time()
frame.data.append(d_val)
frame.error.append(er_val)
class RgmiiPhy:
def __init__(self, txd, tx_ctl, tx_clk, rxd, rx_ctl, rx_clk, reset=None,
reset_active_level=True, speed=1000e6, *args, **kwargs):
self.tx_clk = tx_clk
self.rx_clk = rx_clk
super().__init__(*args, **kwargs)
self.tx = RgmiiSink(txd, tx_ctl, tx_clk, reset, reset_active_level=reset_active_level)
self.rx = RgmiiSource(rxd, rx_ctl, rx_clk, reset, 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.scheduler.start_soon(self._run_clock(8*1e9/self.speed))
self.tx.mii_mode = False
self.rx.mii_mode = False
else:
self._clock_cr = cocotb.scheduler.start_soon(self._run_clock(4*1e9/self.speed))
self.tx.mii_mode = True
self.rx.mii_mode = True
async def _run_clock(self, period):
half_period = get_sim_steps(period / 2.0, 'ns')
t = Timer(half_period)
while True:
await t
self.rx_clk <= 1
await t
self.rx_clk <= 0