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Add serial Wishbone bridge

Files copied directly from https://github.com/enjoy-digital/sayma_test @ 9ce2cba87896d056819dc2edc54f0453a86162c3
This commit is contained in:
Florent Kermarrec 2017-08-21 12:21:14 -04:00 committed by Sebastien Bourdeauducq
parent d6b624dfbe
commit 44dc76e42e
5 changed files with 1888 additions and 0 deletions

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"""
Etherbone
CERN's Etherbone protocol is initially used to run a Wishbone bus over an
ethernet network. This re-implementation is meant to be run over serdes
and introduces some limitations:
- no probing (pf/pr)
- no address spaces (rca/bca/wca/wff)
- 32bits data and address
- 1 record per frame
"""
from migen import *
from misoc.interconnect import stream
from misoc.interconnect import wishbone
from amc_rtm_link.packet import *
class Packetizer(Module):
def __init__(self, sink_description, source_description, header):
self.sink = sink = stream.Endpoint(sink_description)
self.source = source = stream.Endpoint(source_description)
self.header = Signal(header.length*8)
# # #
dw = len(self.sink.data)
header_reg = Signal(header.length*8, reset_less=True)
header_words = (header.length*8)//dw
load = Signal()
shift = Signal()
counter = Signal(max=max(header_words, 2))
counter_reset = Signal()
counter_ce = Signal()
self.sync += \
If(counter_reset,
counter.eq(0)
).Elif(counter_ce,
counter.eq(counter + 1)
)
self.comb += header.encode(sink, self.header)
if header_words == 1:
self.sync += [
If(load,
header_reg.eq(self.header)
)
]
else:
self.sync += [
If(load,
header_reg.eq(self.header)
).Elif(shift,
header_reg.eq(Cat(header_reg[dw:], Signal(dw)))
)
]
fsm = FSM(reset_state="IDLE")
self.submodules += fsm
if header_words == 1:
idle_next_state = "COPY"
else:
idle_next_state = "SEND_HEADER"
fsm.act("IDLE",
sink.ack.eq(1),
counter_reset.eq(1),
If(sink.stb,
sink.ack.eq(0),
source.stb.eq(1),
source.eop.eq(0),
source.data.eq(self.header[:dw]),
If(source.stb & source.ack,
load.eq(1),
NextState(idle_next_state)
)
)
)
if header_words != 1:
fsm.act("SEND_HEADER",
source.stb.eq(1),
source.eop.eq(0),
source.data.eq(header_reg[dw:2*dw]),
If(source.stb & source.ack,
shift.eq(1),
counter_ce.eq(1),
If(counter == header_words-2,
NextState("COPY")
)
)
)
if hasattr(sink, "error"):
self.comb += source.error.eq(sink.error)
fsm.act("COPY",
source.stb.eq(sink.stb),
source.eop.eq(sink.eop),
source.data.eq(sink.data),
If(source.stb & source.ack,
sink.ack.eq(1),
If(source.eop,
NextState("IDLE")
)
)
)
class Depacketizer(Module):
def __init__(self, sink_description, source_description, header):
self.sink = sink = stream.Endpoint(sink_description)
self.source = source = stream.Endpoint(source_description)
self.header = Signal(header.length*8)
# # #
dw = len(sink.data)
header_reg = Signal(header.length*8, reset_less=True)
header_words = (header.length*8)//dw
shift = Signal()
counter = Signal(max=max(header_words, 2))
counter_reset = Signal()
counter_ce = Signal()
self.sync += \
If(counter_reset,
counter.eq(0)
).Elif(counter_ce,
counter.eq(counter + 1)
)
if header_words == 1:
self.sync += \
If(shift,
header_reg.eq(sink.data)
)
else:
self.sync += \
If(shift,
header_reg.eq(Cat(header_reg[dw:], sink.data))
)
self.comb += self.header.eq(header_reg)
fsm = FSM(reset_state="IDLE")
self.submodules += fsm
if header_words == 1:
idle_next_state = "COPY"
else:
idle_next_state = "RECEIVE_HEADER"
fsm.act("IDLE",
sink.ack.eq(1),
counter_reset.eq(1),
If(sink.stb,
shift.eq(1),
NextState(idle_next_state)
)
)
if header_words != 1:
fsm.act("RECEIVE_HEADER",
sink.ack.eq(1),
If(sink.stb,
counter_ce.eq(1),
shift.eq(1),
If(counter == header_words-2,
NextState("COPY")
)
)
)
no_payload = Signal()
self.sync += \
If(fsm.before_entering("COPY"),
no_payload.eq(sink.eop)
)
if hasattr(sink, "error"):
self.comb += source.error.eq(sink.error)
self.comb += [
source.eop.eq(sink.eop | no_payload),
source.data.eq(sink.data),
header.decode(self.header, source)
]
fsm.act("COPY",
sink.ack.eq(source.ack),
source.stb.eq(sink.stb | no_payload),
If(source.stb & source.ack & source.eop,
NextState("IDLE")
)
)
etherbone_magic = 0x4e6f
etherbone_version = 1
etherbone_packet_header_length = 8
etherbone_packet_header_fields = {
"magic": HeaderField(0, 0, 16),
"version": HeaderField(2, 4, 4),
"nr": HeaderField(2, 2, 1),
"pr": HeaderField(2, 1, 1), # unused
"pf": HeaderField(2, 0, 1), # unused
"addr_size": HeaderField(3, 4, 4), # static
"port_size": HeaderField(3, 0, 4) # static
}
etherbone_packet_header = Header(etherbone_packet_header_fields,
etherbone_packet_header_length,
swap_field_bytes=True)
etherbone_record_header_length = 4
etherbone_record_header_fields = {
"bca": HeaderField(0, 0, 1), # unused
"rca": HeaderField(0, 1, 1), # unused
"rff": HeaderField(0, 2, 1), # unused
"cyc": HeaderField(0, 4, 1), # unused
"wca": HeaderField(0, 5, 1), # unused
"wff": HeaderField(0, 6, 1), # unused
"byte_enable": HeaderField(1, 0, 8),
"wcount": HeaderField(2, 0, 8),
"rcount": HeaderField(3, 0, 8)
}
etherbone_record_header = Header(etherbone_record_header_fields,
etherbone_record_header_length,
swap_field_bytes=True)
def _remove_from_layout(layout, *args):
r = []
for f in layout:
remove = False
for arg in args:
if f[0] == arg:
remove = True
if not remove:
r.append(f)
return r
def etherbone_packet_description(dw):
layout = etherbone_packet_header.get_layout()
layout += [("data", dw)]
return stream.EndpointDescription(layout)
def etherbone_packet_user_description(dw):
layout = etherbone_packet_header.get_layout()
layout = _remove_from_layout(layout,
"magic",
"portsize",
"addrsize",
"version")
layout += user_description(dw).payload_layout
return stream.EndpointDescription(layout)
def etherbone_record_description(dw):
layout = etherbone_record_header.get_layout()
layout += [("data", dw)]
return stream.EndpointDescription(layout)
def etherbone_mmap_description(dw):
layout = [
("we", 1),
("count", 8),
("base_addr", 32),
("be", dw//8),
("addr", 32),
("data", dw)
]
return stream.EndpointDescription(layout)
# etherbone packet
class EtherbonePacketPacketizer(Packetizer):
def __init__(self):
Packetizer.__init__(self,
etherbone_packet_description(32),
user_description(32),
etherbone_packet_header)
class EtherbonePacketTX(Module):
def __init__(self):
self.sink = sink = stream.Endpoint(etherbone_packet_user_description(32))
self.source = source = stream.Endpoint(user_description(32))
# # #
self.submodules.packetizer = packetizer = EtherbonePacketPacketizer()
self.comb += [
packetizer.sink.stb.eq(sink.stb),
packetizer.sink.eop.eq(sink.eop),
sink.ack.eq(packetizer.sink.ack),
packetizer.sink.magic.eq(etherbone_magic),
packetizer.sink.port_size.eq(32//8),
packetizer.sink.addr_size.eq(32//8),
packetizer.sink.nr.eq(sink.nr),
packetizer.sink.version.eq(etherbone_version),
packetizer.sink.data.eq(sink.data)
]
self.submodules.fsm = fsm = FSM(reset_state="IDLE")
fsm.act("IDLE",
packetizer.source.ack.eq(1),
If(packetizer.source.stb,
packetizer.source.ack.eq(0),
NextState("SEND")
)
)
fsm.act("SEND",
packetizer.source.connect(source),
source.length.eq(sink.length + etherbone_packet_header.length),
If(source.stb & source.eop & source.ack,
NextState("IDLE")
)
)
class EtherbonePacketDepacketizer(Depacketizer):
def __init__(self):
Depacketizer.__init__(self,
user_description(32),
etherbone_packet_description(32),
etherbone_packet_header)
class EtherbonePacketRX(Module):
def __init__(self):
self.sink = sink = stream.Endpoint(user_description(32))
self.source = source = stream.Endpoint(etherbone_packet_user_description(32))
# # #
self.submodules.depacketizer = depacketizer = EtherbonePacketDepacketizer()
self.comb += sink.connect(depacketizer.sink)
self.submodules.fsm = fsm = FSM(reset_state="IDLE")
fsm.act("IDLE",
depacketizer.source.ack.eq(1),
If(depacketizer.source.stb,
depacketizer.source.ack.eq(0),
NextState("CHECK")
)
)
stb = Signal()
self.sync += stb.eq(
depacketizer.source.stb &
(depacketizer.source.magic == etherbone_magic)
)
fsm.act("CHECK",
If(stb,
NextState("PRESENT")
).Else(
NextState("DROP")
)
)
self.comb += [
source.eop.eq(depacketizer.source.eop),
source.nr.eq(depacketizer.source.nr),
source.data.eq(depacketizer.source.data),
source.length.eq(sink.length - etherbone_packet_header.length)
]
fsm.act("PRESENT",
source.stb.eq(depacketizer.source.stb),
depacketizer.source.ack.eq(source.ack),
If(source.stb & source.eop & source.ack,
NextState("IDLE")
)
)
fsm.act("DROP",
depacketizer.source.ack.eq(1),
If(depacketizer.source.stb &
depacketizer.source.eop &
depacketizer.source.ack,
NextState("IDLE")
)
)
class EtherbonePacket(Module):
def __init__(self, port_sink, port_source):
self.submodules.tx = tx = EtherbonePacketTX()
self.submodules.rx = rx = EtherbonePacketRX()
self.comb += [
tx.source.connect(port_sink),
port_source.connect(rx.sink)
]
self.sink, self.source = self.tx.sink, self.rx.source
# etherbone record
class EtherboneRecordPacketizer(Packetizer):
def __init__(self):
Packetizer.__init__(self,
etherbone_record_description(32),
etherbone_packet_user_description(32),
etherbone_record_header)
class EtherboneRecordDepacketizer(Depacketizer):
def __init__(self):
Depacketizer.__init__(self,
etherbone_packet_user_description(32),
etherbone_record_description(32),
etherbone_record_header)
class EtherboneRecordReceiver(Module):
def __init__(self, buffer_depth=256):
self.sink = sink = stream.Endpoint(etherbone_record_description(32))
self.source = source = stream.Endpoint(etherbone_mmap_description(32))
# # #
fifo = stream.SyncFIFO(etherbone_record_description(32), buffer_depth,
buffered=True)
self.submodules += fifo
self.comb += sink.connect(fifo.sink)
base_addr = Signal(32)
base_addr_update = Signal()
self.sync += If(base_addr_update, base_addr.eq(fifo.source.data))
counter = Signal(max=512)
counter_reset = Signal()
counter_ce = Signal()
self.sync += \
If(counter_reset,
counter.eq(0)
).Elif(counter_ce,
counter.eq(counter + 1)
)
self.submodules.fsm = fsm = FSM(reset_state="IDLE")
fsm.act("IDLE",
fifo.source.ack.eq(1),
counter_reset.eq(1),
If(fifo.source.stb,
base_addr_update.eq(1),
If(fifo.source.wcount,
NextState("RECEIVE_WRITES")
).Elif(fifo.source.rcount,
NextState("RECEIVE_READS")
)
)
)
fsm.act("RECEIVE_WRITES",
source.stb.eq(fifo.source.stb),
source.eop.eq(counter == fifo.source.wcount-1),
source.count.eq(fifo.source.wcount),
source.be.eq(fifo.source.byte_enable),
source.addr.eq(base_addr[2:] + counter),
source.we.eq(1),
source.data.eq(fifo.source.data),
fifo.source.ack.eq(source.ack),
If(source.stb & source.ack,
counter_ce.eq(1),
If(source.eop,
If(fifo.source.rcount,
NextState("RECEIVE_BASE_RET_ADDR")
).Else(
NextState("IDLE")
)
)
)
)
fsm.act("RECEIVE_BASE_RET_ADDR",
counter_reset.eq(1),
If(fifo.source.stb,
base_addr_update.eq(1),
NextState("RECEIVE_READS")
)
)
fsm.act("RECEIVE_READS",
source.stb.eq(fifo.source.stb),
source.eop.eq(counter == fifo.source.rcount-1),
source.count.eq(fifo.source.rcount),
source.base_addr.eq(base_addr),
source.addr.eq(fifo.source.data[2:]),
fifo.source.ack.eq(source.ack),
If(source.stb & source.ack,
counter_ce.eq(1),
If(source.eop,
NextState("IDLE")
)
)
)
class EtherboneRecordSender(Module):
def __init__(self, buffer_depth=256):
self.sink = sink = stream.Endpoint(etherbone_mmap_description(32))
self.source = source = stream.Endpoint(etherbone_record_description(32))
# # #
pbuffer = stream.SyncFIFO(etherbone_mmap_description(32), buffer_depth)
self.submodules += pbuffer
self.comb += sink.connect(pbuffer.sink)
self.submodules.fsm = fsm = FSM(reset_state="IDLE")
fsm.act("IDLE",
pbuffer.source.ack.eq(1),
If(pbuffer.source.stb,
pbuffer.source.ack.eq(0),
NextState("SEND_BASE_ADDRESS")
)
)
self.comb += [
source.byte_enable.eq(pbuffer.source.be),
If(pbuffer.source.we,
source.wcount.eq(pbuffer.source.count)
).Else(
source.rcount.eq(pbuffer.source.count)
)
]
fsm.act("SEND_BASE_ADDRESS",
source.stb.eq(pbuffer.source.stb),
source.eop.eq(0),
source.data.eq(pbuffer.source.base_addr),
If(source.ack,
NextState("SEND_DATA")
)
)
fsm.act("SEND_DATA",
source.stb.eq(pbuffer.source.stb),
source.eop.eq(pbuffer.source.eop),
source.data.eq(pbuffer.source.data),
If(source.stb & source.ack,
pbuffer.source.ack.eq(1),
If(source.eop,
NextState("IDLE")
)
)
)
class EtherboneRecord(Module):
def __init__(self):
self.sink = sink = stream.Endpoint(etherbone_packet_user_description(32))
self.source = source = stream.Endpoint(etherbone_packet_user_description(32))
# # #
# receive record, decode it and generate mmap stream
self.submodules.depacketizer = depacketizer = EtherboneRecordDepacketizer()
self.submodules.receiver = receiver = EtherboneRecordReceiver()
self.comb += [
sink.connect(depacketizer.sink),
depacketizer.source.connect(receiver.sink)
]
# receive mmap stream, encode it and send records
self.submodules.sender = sender = EtherboneRecordSender()
self.submodules.packetizer = packetizer = EtherboneRecordPacketizer()
self.comb += [
sender.source.connect(packetizer.sink),
packetizer.source.connect(source),
source.length.eq(etherbone_record_header.length +
(sender.source.wcount != 0)*4 + sender.source.wcount*4 +
(sender.source.rcount != 0)*4 + sender.source.rcount*4)
]
# etherbone wishbone
class EtherboneWishboneMaster(Module):
def __init__(self):
self.sink = sink = stream.Endpoint(etherbone_mmap_description(32))
self.source = source = stream.Endpoint(etherbone_mmap_description(32))
self.bus = bus = wishbone.Interface()
# # #
data = Signal(32)
data_update = Signal()
self.sync += If(data_update, data.eq(bus.dat_r))
self.submodules.fsm = fsm = FSM(reset_state="IDLE")
fsm.act("IDLE",
sink.ack.eq(1),
If(sink.stb,
sink.ack.eq(0),
If(sink.we,
NextState("WRITE_DATA")
).Else(
NextState("READ_DATA")
)
)
)
fsm.act("WRITE_DATA",
bus.adr.eq(sink.addr),
bus.dat_w.eq(sink.data),
bus.sel.eq(sink.be),
bus.stb.eq(sink.stb),
bus.we.eq(1),
bus.cyc.eq(1),
If(bus.stb & bus.ack,
sink.ack.eq(1),
If(sink.eop,
NextState("IDLE")
)
)
)
fsm.act("READ_DATA",
bus.adr.eq(sink.addr),
bus.sel.eq(sink.be),
bus.stb.eq(sink.stb),
bus.cyc.eq(1),
If(bus.stb & bus.ack,
data_update.eq(1),
NextState("SEND_DATA")
)
)
fsm.act("SEND_DATA",
source.stb.eq(sink.stb),
source.eop.eq(sink.eop),
source.base_addr.eq(sink.base_addr),
source.addr.eq(sink.addr),
source.count.eq(sink.count),
source.be.eq(sink.be),
source.we.eq(1),
source.data.eq(data),
If(source.stb & source.ack,
sink.ack.eq(1),
If(source.eop,
NextState("IDLE")
).Else(
NextState("READ_DATA")
)
)
)
class EtherboneWishboneSlave(Module):
def __init__(self):
self.bus = bus = wishbone.Interface()
self.sink = sink = stream.Endpoint(etherbone_mmap_description(32))
self.source = source = stream.Endpoint(etherbone_mmap_description(32))
# # #
self.submodules.fsm = fsm = FSM(reset_state="IDLE")
fsm.act("IDLE",
sink.ack.eq(1),
If(bus.stb & bus.cyc,
If(bus.we,
NextState("SEND_WRITE")
).Else(
NextState("SEND_READ")
)
)
)
fsm.act("SEND_WRITE",
source.stb.eq(1),
source.eop.eq(1),
source.base_addr[2:].eq(bus.adr),
source.count.eq(1),
source.be.eq(bus.sel),
source.we.eq(1),
source.data.eq(bus.dat_w),
If(source.stb & source.ack,
bus.ack.eq(1),
NextState("IDLE")
)
)
fsm.act("SEND_READ",
source.stb.eq(1),
source.eop.eq(1),
source.base_addr.eq(0),
source.count.eq(1),
source.be.eq(bus.sel),
source.we.eq(0),
source.data[2:].eq(bus.adr),
If(source.stb & source.ack,
NextState("WAIT_READ")
)
)
fsm.act("WAIT_READ",
sink.ack.eq(1),
If(sink.stb & sink.we,
bus.ack.eq(1),
bus.dat_r.eq(sink.data),
NextState("IDLE")
)
)
# etherbone
class Etherbone(Module):
def __init__(self, mode="master"):
self.sink = sink = stream.Endpoint(user_description(32))
self.source = source = stream.Endpoint(user_description(32))
# # #
self.submodules.packet = EtherbonePacket(source, sink)
self.submodules.record = EtherboneRecord()
if mode == "master":
self.submodules.wishbone = EtherboneWishboneMaster()
elif mode == "slave":
self.submodules.wishbone = EtherboneWishboneSlave()
else:
raise ValueError
self.comb += [
self.packet.source.connect(self.record.sink),
self.record.source.connect(self.packet.sink),
self.record.receiver.source.connect(self.wishbone.sink),
self.wishbone.source.connect(self.record.sender.sink)
]

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from migen import *
from migen.genlib.resetsync import AsyncResetSynchronizer
from migen.genlib.cdc import MultiReg, PulseSynchronizer, Gearbox
from migen.genlib.misc import BitSlip
from misoc.cores.code_8b10b import Encoder, Decoder
from amc_rtm_link.phy import PhaseDetector
class KUSSerdesPLL(Module):
def __init__(self, refclk_freq, linerate, vco_div=1):
assert refclk_freq == 125e6
assert linerate == 1.25e9
self.lock = Signal()
self.refclk = Signal()
self.serdes_clk = Signal()
self.serdes_20x_clk = Signal()
self.serdes_5x_clk = Signal()
# # #
#----------------------
# refclk: 125MHz
# vco: 1250MHz
#----------------------
# serdes: 31.25MHz
# serdes_20x: 625MHz
# serdes_5x: 156.25MHz
#----------------------
self.linerate = linerate
pll_locked = Signal()
pll_fb = Signal()
pll_serdes_clk = Signal()
pll_serdes_20x_clk = Signal()
pll_serdes_5x_clk = Signal()
self.specials += [
Instance("PLLE2_BASE",
p_STARTUP_WAIT="FALSE", o_LOCKED=pll_locked,
# VCO @ 1.25GHz / vco_div
p_REF_JITTER1=0.01, p_CLKIN1_PERIOD=8.0,
p_CLKFBOUT_MULT=10, p_DIVCLK_DIVIDE=vco_div,
i_CLKIN1=self.refclk, i_CLKFBIN=pll_fb,
o_CLKFBOUT=pll_fb,
# 31.25MHz: serdes
p_CLKOUT0_DIVIDE=40//vco_div, p_CLKOUT0_PHASE=0.0,
o_CLKOUT0=pll_serdes_clk,
# 625MHz: serdes_20x
p_CLKOUT1_DIVIDE=2//vco_div, p_CLKOUT1_PHASE=0.0,
o_CLKOUT1=pll_serdes_20x_clk,
# 156.25MHz: serdes_5x
p_CLKOUT2_DIVIDE=8//vco_div, p_CLKOUT2_PHASE=0.0,
o_CLKOUT2=pll_serdes_5x_clk
),
Instance("BUFG", i_I=pll_serdes_clk, o_O=self.serdes_clk),
Instance("BUFG", i_I=pll_serdes_20x_clk, o_O=self.serdes_20x_clk),
Instance("BUFG", i_I=pll_serdes_5x_clk, o_O=self.serdes_5x_clk)
]
self.specials += MultiReg(pll_locked, self.lock)
class KUSSerdes(Module):
def __init__(self, pll, pads, mode="master"):
self.tx_data = Signal(32)
self.rx_data = Signal(32)
self.tx_idle = Signal()
self.tx_comma = Signal()
self.rx_idle = Signal()
self.rx_comma = Signal()
self.rx_bitslip_value = Signal(6)
self.rx_delay_rst = Signal()
self.rx_delay_inc = Signal()
self.rx_delay_ce = Signal()
self.rx_delay_en_vtc = Signal()
# # #
self.submodules.encoder = ClockDomainsRenamer("serdes")(
Encoder(4, True))
self.decoders = [ClockDomainsRenamer("serdes")(
Decoder(True)) for _ in range(4)]
self.submodules += self.decoders
# clocking:
# In master mode:
# - linerate/10 pll refclk provided by user
# - linerate/10 slave refclk generated on clk_pads
# In Slave mode:
# - linerate/10 pll refclk provided by clk_pads
self.clock_domains.cd_serdes = ClockDomain()
self.clock_domains.cd_serdes_5x = ClockDomain()
self.clock_domains.cd_serdes_20x = ClockDomain(reset_less=True)
self.comb += [
self.cd_serdes.clk.eq(pll.serdes_clk),
self.cd_serdes_5x.clk.eq(pll.serdes_5x_clk),
self.cd_serdes_20x.clk.eq(pll.serdes_20x_clk)
]
self.specials += AsyncResetSynchronizer(self.cd_serdes, ~pll.lock)
self.comb += self.cd_serdes_5x.rst.eq(self.cd_serdes.rst)
# control/status cdc
tx_idle = Signal()
tx_comma = Signal()
rx_idle = Signal()
rx_comma = Signal()
rx_bitslip_value = Signal(6)
rx_delay_rst = Signal()
rx_delay_inc = Signal()
rx_delay_en_vtc = Signal()
rx_delay_ce = Signal()
self.specials += [
MultiReg(self.tx_idle, tx_idle, "serdes"),
MultiReg(self.tx_comma, tx_comma, "serdes"),
MultiReg(rx_idle, self.rx_idle, "sys"),
MultiReg(rx_comma, self.rx_comma, "sys"),
MultiReg(self.rx_bitslip_value, rx_bitslip_value, "serdes"),
MultiReg(self.rx_delay_inc, rx_delay_inc, "serdes_5x"),
MultiReg(self.rx_delay_en_vtc, rx_delay_en_vtc, "serdes_5x")
]
self.submodules.do_rx_delay_rst = PulseSynchronizer("sys", "serdes_5x")
self.comb += [
rx_delay_rst.eq(self.do_rx_delay_rst.o),
self.do_rx_delay_rst.i.eq(self.rx_delay_rst)
]
self.submodules.do_rx_delay_ce = PulseSynchronizer("sys", "serdes_5x")
self.comb += [
rx_delay_ce.eq(self.do_rx_delay_ce.o),
self.do_rx_delay_ce.i.eq(self.rx_delay_ce)
]
# tx clock (linerate/10)
if mode == "master":
self.submodules.tx_clk_gearbox = Gearbox(40, "serdes", 8, "serdes_5x")
self.comb += self.tx_clk_gearbox.i.eq((0b1111100000 << 30) |
(0b1111100000 << 20) |
(0b1111100000 << 10) |
(0b1111100000 << 0))
clk_o = Signal()
self.specials += [
Instance("OSERDESE3",
p_DATA_WIDTH=8, p_INIT=0,
p_IS_CLK_INVERTED=0, p_IS_CLKDIV_INVERTED=0, p_IS_RST_INVERTED=0,
o_OQ=clk_o,
i_RST=ResetSignal("serdes"),
i_CLK=ClockSignal("serdes_20x"), i_CLKDIV=ClockSignal("serdes_5x"),
i_D=self.tx_clk_gearbox.o
),
Instance("OBUFDS",
i_I=clk_o,
o_O=pads.clk_p,
o_OB=pads.clk_n
)
]
# tx datapath
# tx_data -> encoders -> gearbox -> serdes
self.submodules.tx_gearbox = Gearbox(40, "serdes", 8, "serdes_5x")
self.comb += [
If(tx_comma,
self.encoder.k[0].eq(1),
self.encoder.d[0].eq(0xbc)
).Else(
self.encoder.d[0].eq(self.tx_data[0:8]),
self.encoder.d[1].eq(self.tx_data[8:16]),
self.encoder.d[2].eq(self.tx_data[16:24]),
self.encoder.d[3].eq(self.tx_data[24:32])
)
]
self.sync.serdes += \
If(tx_idle,
self.tx_gearbox.i.eq(0)
).Else(
self.tx_gearbox.i.eq(Cat(*[self.encoder.output[i] for i in range(4)]))
)
serdes_o = Signal()
self.specials += [
Instance("OSERDESE3",
p_DATA_WIDTH=8, p_INIT=0,
p_IS_CLK_INVERTED=0, p_IS_CLKDIV_INVERTED=0, p_IS_RST_INVERTED=0,
o_OQ=serdes_o,
i_RST=ResetSignal("serdes"),
i_CLK=ClockSignal("serdes_20x"), i_CLKDIV=ClockSignal("serdes_5x"),
i_D=self.tx_gearbox.o
),
Instance("OBUFDS",
i_I=serdes_o,
o_O=pads.tx_p,
o_OB=pads.tx_n
)
]
# rx clock
use_bufr = True
if mode == "slave":
clk_i = Signal()
clk_i_bufg = Signal()
self.specials += [
Instance("IBUFDS",
i_I=pads.clk_p,
i_IB=pads.clk_n,
o_O=clk_i
)
]
if use_bufr:
clk_i_bufr = Signal()
self.specials += [
Instance("BUFR", i_I=clk_i, o_O=clk_i_bufr),
Instance("BUFG", i_I=clk_i_bufr, o_O=clk_i_bufg)
]
else:
self.specials += Instance("BUFG", i_I=clk_i, o_O=clk_i_bufg)
self.comb += pll.refclk.eq(clk_i_bufg)
# rx datapath
# serdes -> gearbox -> bitslip -> decoders -> rx_data
self.submodules.rx_gearbox = Gearbox(8, "serdes_5x", 40, "serdes")
self.submodules.rx_bitslip = ClockDomainsRenamer("serdes")(BitSlip(40))
self.submodules.phase_detector = ClockDomainsRenamer("serdes_5x")(PhaseDetector())
# 2 serdes for phase detection: 1 master (used for data) / 1 slave
serdes_m_i_nodelay = Signal()
serdes_s_i_nodelay = Signal()
self.specials += [
Instance("IBUFDS_DIFF_OUT",
i_I=pads.rx_p,
i_IB=pads.rx_n,
o_O=serdes_m_i_nodelay,
o_OB=serdes_s_i_nodelay
)
]
serdes_m_i_delayed = Signal()
serdes_m_q = Signal(8)
self.specials += [
Instance("IDELAYE3",
p_CASCADE="NONE", p_UPDATE_MODE="ASYNC", p_REFCLK_FREQUENCY=200.0,
p_IS_CLK_INVERTED=0, p_IS_RST_INVERTED=0,
p_DELAY_FORMAT="COUNT", p_DELAY_SRC="IDATAIN",
p_DELAY_TYPE="VARIABLE", p_DELAY_VALUE=0,
i_CLK=ClockSignal("serdes_5x"),
i_RST=rx_delay_rst, i_LOAD=0,
i_INC=rx_delay_inc, i_EN_VTC=rx_delay_en_vtc,
i_CE=rx_delay_ce,
i_IDATAIN=serdes_m_i_nodelay, o_DATAOUT=serdes_m_i_delayed
),
Instance("ISERDESE3",
p_DATA_WIDTH=8,
i_D=serdes_m_i_delayed,
i_RST=ResetSignal("serdes"),
i_FIFO_RD_CLK=0, i_FIFO_RD_EN=0,
i_CLK=ClockSignal("serdes_20x"), i_CLK_B=~ClockSignal("serdes_20x"),
i_CLKDIV=ClockSignal("serdes_5x"),
o_Q=serdes_m_q
)
]
self.comb += self.phase_detector.mdata.eq(serdes_m_q)
serdes_s_i_delayed = Signal()
serdes_s_q = Signal(8)
self.specials += [
Instance("IDELAYE3",
p_CASCADE="NONE", p_UPDATE_MODE="ASYNC", p_REFCLK_FREQUENCY=200.0,
p_IS_CLK_INVERTED=0, p_IS_RST_INVERTED=0,
# Note: can't use TIME mode since not reloading DELAY_VALUE on rst...
# Got answer from Xilinx, need testing:
# https://forums.xilinx.com/xlnx/board/crawl_message?board.id=ultrascale&message.id=4699
p_DELAY_FORMAT="COUNT", p_DELAY_SRC="IDATAIN",
p_DELAY_TYPE="VARIABLE", p_DELAY_VALUE=50, # 1/4 bit period (ambient temp)
i_CLK=ClockSignal("serdes_5x"),
i_RST=rx_delay_rst, i_LOAD=0,
i_INC=rx_delay_inc, i_EN_VTC=rx_delay_en_vtc,
i_CE=rx_delay_ce,
i_IDATAIN=serdes_s_i_nodelay, o_DATAOUT=serdes_s_i_delayed
),
Instance("ISERDESE3",
p_DATA_WIDTH=8,
i_D=serdes_s_i_delayed,
i_RST=ResetSignal("serdes"),
i_FIFO_RD_CLK=0, i_FIFO_RD_EN=0,
i_CLK=ClockSignal("serdes_20x"), i_CLK_B=~ClockSignal("serdes_20x"),
i_CLKDIV=ClockSignal("serdes_5x"),
o_Q=serdes_s_q
)
]
self.comb += self.phase_detector.sdata.eq(~serdes_s_q)
self.comb += [
self.rx_gearbox.i.eq(serdes_m_q),
self.rx_bitslip.value.eq(rx_bitslip_value),
self.rx_bitslip.i.eq(self.rx_gearbox.o),
self.decoders[0].input.eq(self.rx_bitslip.o[0:10]),
self.decoders[1].input.eq(self.rx_bitslip.o[10:20]),
self.decoders[2].input.eq(self.rx_bitslip.o[20:30]),
self.decoders[3].input.eq(self.rx_bitslip.o[30:40]),
self.rx_data.eq(Cat(*[self.decoders[i].d for i in range(4)])),
rx_idle.eq(self.rx_bitslip.o == 0),
rx_comma.eq(((self.decoders[0].d == 0xbc) & (self.decoders[0].k == 1)) &
((self.decoders[1].d == 0x00) & (self.decoders[1].k == 0)) &
((self.decoders[2].d == 0x00) & (self.decoders[2].k == 0)) &
((self.decoders[3].d == 0x00) & (self.decoders[3].k == 0)))
]

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from math import ceil
from copy import copy
from collections import OrderedDict
from migen import *
from migen.genlib.misc import WaitTimer
from misoc.interconnect import stream
from misoc.interconnect.stream import EndpointDescription
def reverse_bytes(signal):
n = ceil(len(signal)/8)
return Cat(iter([signal[i*8:(i+1)*8] for i in reversed(range(n))]))
class HeaderField:
def __init__(self, byte, offset, width):
self.byte = byte
self.offset = offset
self.width = width
class Header:
def __init__(self, fields, length, swap_field_bytes=True):
self.fields = fields
self.length = length
self.swap_field_bytes = swap_field_bytes
def get_layout(self):
layout = []
for k, v in sorted(self.fields.items()):
layout.append((k, v.width))
return layout
def get_field(self, obj, name, width):
if "_lsb" in name:
field = getattr(obj, name.replace("_lsb", ""))[:width]
elif "_msb" in name:
field = getattr(obj, name.replace("_msb", ""))[width:2*width]
else:
field = getattr(obj, name)
if len(field) != width:
raise ValueError("Width mismatch on " + name + " field")
return field
def encode(self, obj, signal):
r = []
for k, v in sorted(self.fields.items()):
start = v.byte*8 + v.offset
end = start + v.width
field = self.get_field(obj, k, v.width)
if self.swap_field_bytes:
field = reverse_bytes(field)
r.append(signal[start:end].eq(field))
return r
def decode(self, signal, obj):
r = []
for k, v in sorted(self.fields.items()):
start = v.byte*8 + v.offset
end = start + v.width
field = self.get_field(obj, k, v.width)
if self.swap_field_bytes:
r.append(field.eq(reverse_bytes(signal[start:end])))
else:
r.append(field.eq(signal[start:end]))
return r
def phy_description(dw):
layout = [("data", dw)]
return stream.EndpointDescription(layout)
def user_description(dw):
layout = [
("data", 32),
("length", 32)
]
return stream.EndpointDescription(layout)
class Packetizer(Module):
def __init__(self):
self.sink = sink = stream.Endpoint(user_description(32))
self.source = source = stream.Endpoint(phy_description(32))
# # #
# Packet description
# - preamble : 4 bytes
# - length : 4 bytes
# - payload
fsm = FSM(reset_state="IDLE")
self.submodules += fsm
fsm.act("IDLE",
If(sink.stb,
NextState("INSERT_PREAMBLE")
)
)
fsm.act("INSERT_PREAMBLE",
source.stb.eq(1),
source.data.eq(0x5aa55aa5),
If(source.ack,
NextState("INSERT_LENGTH")
)
)
fsm.act("INSERT_LENGTH",
source.stb.eq(1),
source.data.eq(sink.length),
If(source.ack,
NextState("COPY")
)
)
fsm.act("COPY",
source.stb.eq(sink.stb),
source.data.eq(sink.data),
sink.ack.eq(source.ack),
If(source.ack & sink.eop,
NextState("IDLE")
)
)
class Depacketizer(Module):
def __init__(self, clk_freq, timeout=10):
self.sink = sink = stream.Endpoint(phy_description(32))
self.source = source = stream.Endpoint(user_description(32))
# # #
# Packet description
# - preamble : 4 bytes
# - length : 4 bytes
# - payload
fsm = FSM(reset_state="IDLE")
self.submodules += fsm
self.submodules.timer = WaitTimer(clk_freq*timeout)
self.comb += self.timer.wait.eq(~fsm.ongoing("IDLE"))
fsm.act("IDLE",
sink.ack.eq(1),
If(sink.stb & (sink.data == 0x5aa55aa5),
NextState("RECEIVE_LENGTH")
)
)
fsm.act("RECEIVE_LENGTH",
sink.ack.eq(1),
If(sink.stb,
NextValue(source.length, sink.data),
NextState("COPY")
)
)
eop = Signal()
cnt = Signal(32)
fsm.act("COPY",
source.stb.eq(sink.stb),
source.eop.eq(eop),
source.data.eq(sink.data),
sink.ack.eq(source.ack),
If((source.stb & source.ack & eop) | self.timer.done,
NextState("IDLE")
)
)
self.sync += \
If(fsm.ongoing("IDLE"),
cnt.eq(0)
).Elif(source.stb & source.ack,
cnt.eq(cnt + 1)
)
self.comb += eop.eq(cnt == source.length[2:] - 1)

345
artiq/gateware/serwb/phy.py Normal file
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from migen import *
from migen.genlib.cdc import MultiReg, PulseSynchronizer
from migen.genlib.misc import WaitTimer
from misoc.interconnect.csr import *
class PhaseDetector(Module, AutoCSR):
def __init__(self, nbits=8):
self.mdata = Signal(8)
self.sdata = Signal(8)
self.reset = Signal()
self.too_early = Signal()
self.too_late = Signal()
# # #
# Ideal sampling (middle of the eye):
# _____ _____ _____
# | |_____| |_____| |_____| data
# + + + + + + master sampling
# - - - - - - slave sampling (90°/bit period)
# Since taps are fixed length delays, this ideal case is not possible
# and we will fall in the 2 following possible cases:
#
# 1) too late sampling (idelay needs to be decremented):
# _____ _____ _____
# | |_____| |_____| |_____| data
# + + + + + + master sampling
# - - - - - - slave sampling (90°/bit period)
# On mdata transition, mdata != sdata
#
#
# 2) too early sampling (idelay needs to be incremented):
# _____ _____ _____
# | |_____| |_____| |_____| data
# + + + + + + master sampling
# - - - - - - slave sampling (90°/bit period)
# On mdata transition, mdata == sdata
transition = Signal()
inc = Signal()
dec = Signal()
# Find transition
mdata_d = Signal(8)
self.sync.serdes_5x += mdata_d.eq(self.mdata)
self.comb += transition.eq(mdata_d != self.mdata)
# Find what to do
self.comb += [
inc.eq(transition & (self.mdata == self.sdata)),
dec.eq(transition & (self.mdata != self.sdata))
]
# Error accumulator
lateness = Signal(nbits, reset=2**(nbits - 1))
too_late = Signal()
too_early = Signal()
reset_lateness = Signal()
self.comb += [
too_late.eq(lateness == (2**nbits - 1)),
too_early.eq(lateness == 0)
]
self.sync.serdes_5x += [
If(reset_lateness,
lateness.eq(2**(nbits - 1))
).Elif(~too_late & ~too_early,
If(inc, lateness.eq(lateness - 1)),
If(dec, lateness.eq(lateness + 1))
)
]
# control / status cdc
self.specials += [
MultiReg(too_early, self.too_early),
MultiReg(too_late, self.too_late)
]
self.submodules.do_reset_lateness = PulseSynchronizer("sys", "serdes_5x")
self.comb += [
reset_lateness.eq(self.do_reset_lateness.o),
self.do_reset_lateness.i.eq(self.reset)
]
# Master <--> Slave synchronization:
# 1) Master sends idle pattern (zeroes) to reset Slave.
# 2) Master sends K28.5 commas to allow Slave to calibrate, Slave sends idle pattern.
# 3) Slave sends K28.5 commas to allow Master to calibrate, Master sends K28.5 commas.
# 4) Master stops sending K28.5 commas.
# 5) Slave stops sending K25.5 commas.
# 6) Link is ready.
class SerdesMasterInit(Module):
def __init__(self, serdes, taps):
self.reset = Signal()
self.error = Signal()
self.ready = Signal()
# # #
self.delay = delay = Signal(max=taps)
self.delay_found = delay_found = Signal()
self.bitslip = bitslip = Signal(max=40)
self.bitslip_found = bitslip_found = Signal()
timer = WaitTimer(8192)
self.submodules += timer
self.submodules.fsm = fsm = ResetInserter()(FSM(reset_state="IDLE"))
self.comb += self.fsm.reset.eq(self.reset)
phase_detector_too_early_last = Signal()
fsm.act("IDLE",
NextValue(delay_found, 0),
NextValue(delay, 0),
serdes.rx_delay_rst.eq(1),
NextValue(bitslip_found, 0),
NextValue(bitslip, 0),
NextValue(phase_detector_too_early_last, 0),
NextState("RESET_SLAVE"),
serdes.tx_idle.eq(1)
)
fsm.act("RESET_SLAVE",
timer.wait.eq(1),
If(timer.done,
timer.wait.eq(0),
NextState("SEND_PATTERN")
),
serdes.tx_idle.eq(1)
)
fsm.act("SEND_PATTERN",
If(~serdes.rx_idle,
NextState("WAIT_STABLE")
),
serdes.tx_comma.eq(1)
)
fsm.act("WAIT_STABLE",
timer.wait.eq(1),
If(timer.done,
timer.wait.eq(0),
serdes.phase_detector.reset.eq(1),
If(~delay_found,
NextState("CHECK_PHASE")
).Else(
NextState("CHECK_PATTERN")
),
),
serdes.tx_comma.eq(1)
)
fsm.act("CHECK_PHASE",
# Since we are always incrementing delay,
# ideal sampling is found when phase detector
# transitions from too_early to too_late
If(serdes.phase_detector.too_late &
phase_detector_too_early_last,
NextValue(delay_found, 1),
NextState("CHECK_PATTERN")
).Elif(serdes.phase_detector.too_late |
serdes.phase_detector.too_early,
NextValue(phase_detector_too_early_last,
serdes.phase_detector.too_early),
NextState("INC_DELAY")
),
serdes.tx_comma.eq(1)
)
fsm.act("INC_DELAY",
If(delay == (taps - 1),
NextState("ERROR")
).Else(
NextValue(delay, delay + 1),
serdes.rx_delay_inc.eq(1),
serdes.rx_delay_ce.eq(1),
NextState("WAIT_STABLE")
),
serdes.tx_comma.eq(1)
)
fsm.act("CHECK_PATTERN",
If(serdes.rx_comma,
timer.wait.eq(1),
If(timer.done,
NextValue(bitslip_found, 1),
NextState("READY")
)
).Else(
NextState("INC_BITSLIP")
),
serdes.tx_comma.eq(1)
)
self.comb += serdes.rx_bitslip_value.eq(bitslip)
fsm.act("INC_BITSLIP",
If(bitslip == (40 - 1),
NextState("ERROR")
).Else(
NextValue(bitslip, bitslip + 1),
NextState("WAIT_STABLE")
),
serdes.tx_comma.eq(1)
)
fsm.act("READY",
self.ready.eq(1)
)
fsm.act("ERROR",
self.error.eq(1)
)
class SerdesSlaveInit(Module, AutoCSR):
def __init__(self, serdes, taps):
self.reset = Signal()
self.ready = Signal()
self.error = Signal()
# # #
self.delay = delay = Signal(max=taps)
self.delay_found = delay_found = Signal()
self.bitslip = bitslip = Signal(max=40)
self.bitslip_found = bitslip_found = Signal()
timer = WaitTimer(1024)
self.submodules += timer
self.comb += self.reset.eq(serdes.rx_idle)
self.submodules.fsm = fsm = ResetInserter()(FSM(reset_state="IDLE"))
phase_detector_too_early_last = Signal()
fsm.act("IDLE",
NextValue(delay_found, 0),
NextValue(delay, 0),
serdes.rx_delay_rst.eq(1),
NextValue(bitslip_found, 0),
NextValue(bitslip, 0),
NextValue(phase_detector_too_early_last, 0),
NextState("WAIT_STABLE"),
serdes.tx_idle.eq(1)
)
fsm.act("WAIT_STABLE",
timer.wait.eq(1),
If(timer.done,
timer.wait.eq(0),
serdes.phase_detector.reset.eq(1),
If(~delay_found,
NextState("CHECK_PHASE")
).Else(
NextState("CHECK_PATTERN")
),
),
serdes.tx_idle.eq(1)
)
fsm.act("CHECK_PHASE",
# Since we are always incrementing delay,
# ideal sampling is found when phase detector
# transitions from too_early to too_late
If(serdes.phase_detector.too_late &
phase_detector_too_early_last,
NextValue(delay_found, 1),
NextState("CHECK_PATTERN")
).Elif(serdes.phase_detector.too_late |
serdes.phase_detector.too_early,
NextValue(phase_detector_too_early_last,
serdes.phase_detector.too_early),
NextState("INC_DELAY")
),
serdes.tx_idle.eq(1)
)
fsm.act("INC_DELAY",
If(delay == (taps - 1),
NextState("ERROR")
).Else(
NextValue(delay, delay + 1),
serdes.rx_delay_inc.eq(1),
serdes.rx_delay_ce.eq(1),
NextState("WAIT_STABLE")
),
serdes.tx_idle.eq(1)
)
fsm.act("CHECK_PATTERN",
If(serdes.rx_comma,
timer.wait.eq(1),
If(timer.done,
NextValue(bitslip_found, 1),
NextState("SEND_PATTERN")
)
).Else(
NextState("INC_BITSLIP")
),
serdes.tx_idle.eq(1)
)
self.comb += serdes.rx_bitslip_value.eq(bitslip)
fsm.act("INC_BITSLIP",
If(bitslip == (40 - 1),
NextState("ERROR")
).Else(
NextValue(bitslip, bitslip + 1),
NextState("WAIT_STABLE")
),
serdes.tx_idle.eq(1)
)
fsm.act("SEND_PATTERN",
timer.wait.eq(1),
If(timer.done,
If(~serdes.rx_comma,
NextState("READY")
)
),
serdes.tx_comma.eq(1)
)
fsm.act("READY",
self.ready.eq(1)
)
fsm.act("ERROR",
self.error.eq(1)
)
class SerdesControl(Module, AutoCSR):
def __init__(self, init, mode="master"):
if mode == "master":
self.reset = CSR()
self.ready = CSRStatus()
self.error = CSRStatus()
self.delay = CSRStatus(9)
self.delay_found = CSRStatus()
self.bitslip = CSRStatus(6)
self.bitslip_found = CSRStatus()
# # #
if mode == "master":
self.comb += init.reset.eq(self.reset.re)
self.comb += [
self.ready.status.eq(init.ready),
self.error.status.eq(init.error),
self.delay_found.status.eq(init.delay_found),
self.delay.status.eq(init.delay),
self.bitslip_found.status.eq(init.bitslip_found),
self.bitslip.status.eq(init.bitslip)
]

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from migen import *
from migen.genlib.resetsync import AsyncResetSynchronizer
from migen.genlib.cdc import MultiReg, Gearbox
from migen.genlib.misc import BitSlip
from misoc.cores.code_8b10b import Encoder, Decoder
from amc_rtm_link.phy import PhaseDetector
class S7SerdesPLL(Module):
def __init__(self, refclk_freq, linerate, vco_div=1):
assert refclk_freq == 125e6
assert linerate == 1.25e9
self.lock = Signal()
self.refclk = Signal()
self.serdes_clk = Signal()
self.serdes_20x_clk = Signal()
self.serdes_5x_clk = Signal()
# # #
#----------------------
# refclk: 125MHz
# vco: 1250MHz
#----------------------
# serdes: 31.25MHz
# serdes_20x: 625MHz
# serdes_5x: 156.25MHz
#----------------------
self.linerate = linerate
pll_locked = Signal()
pll_fb = Signal()
pll_serdes_clk = Signal()
pll_serdes_20x_clk = Signal()
pll_serdes_5x_clk = Signal()
self.specials += [
Instance("PLLE2_BASE",
p_STARTUP_WAIT="FALSE", o_LOCKED=pll_locked,
# VCO @ 1.25GHz / vco_div
p_REF_JITTER1=0.01, p_CLKIN1_PERIOD=8.0,
p_CLKFBOUT_MULT=10, p_DIVCLK_DIVIDE=vco_div,
i_CLKIN1=self.refclk, i_CLKFBIN=pll_fb,
o_CLKFBOUT=pll_fb,
# 31.25MHz: serdes
p_CLKOUT0_DIVIDE=40//vco_div, p_CLKOUT0_PHASE=0.0,
o_CLKOUT0=pll_serdes_clk,
# 625MHz: serdes_20x
p_CLKOUT1_DIVIDE=2//vco_div, p_CLKOUT1_PHASE=0.0,
o_CLKOUT1=pll_serdes_20x_clk,
# 156.25MHz: serdes_5x
p_CLKOUT2_DIVIDE=8//vco_div, p_CLKOUT2_PHASE=0.0,
o_CLKOUT2=pll_serdes_5x_clk
),
Instance("BUFG", i_I=pll_serdes_clk, o_O=self.serdes_clk),
Instance("BUFG", i_I=pll_serdes_20x_clk, o_O=self.serdes_20x_clk),
Instance("BUFG", i_I=pll_serdes_5x_clk, o_O=self.serdes_5x_clk)
]
self.specials += MultiReg(pll_locked, self.lock)
class S7Serdes(Module):
def __init__(self, pll, pads, mode="master"):
self.tx_data = Signal(32)
self.rx_data = Signal(32)
self.tx_idle = Signal()
self.tx_comma = Signal()
self.rx_idle = Signal()
self.rx_comma = Signal()
self.rx_bitslip_value = Signal(6)
self.rx_delay_rst = Signal()
self.rx_delay_inc = Signal()
self.rx_delay_ce = Signal()
# # #
self.submodules.encoder = ClockDomainsRenamer("serdes")(
Encoder(4, True))
self.decoders = [ClockDomainsRenamer("serdes")(
Decoder(True)) for _ in range(4)]
self.submodules += self.decoders
# clocking:
# In master mode:
# - linerate/10 pll refclk provided by user
# - linerate/10 slave refclk generated on clk_pads
# In Slave mode:
# - linerate/10 pll refclk provided by clk_pads
self.clock_domains.cd_serdes = ClockDomain()
self.clock_domains.cd_serdes_5x = ClockDomain()
self.clock_domains.cd_serdes_20x = ClockDomain(reset_less=True)
self.comb += [
self.cd_serdes.clk.eq(pll.serdes_clk),
self.cd_serdes_5x.clk.eq(pll.serdes_5x_clk),
self.cd_serdes_20x.clk.eq(pll.serdes_20x_clk)
]
self.specials += AsyncResetSynchronizer(self.cd_serdes, ~pll.lock)
self.comb += self.cd_serdes_5x.rst.eq(self.cd_serdes.rst)
# control/status cdc
tx_idle = Signal()
tx_comma = Signal()
rx_idle = Signal()
rx_comma = Signal()
rx_bitslip_value = Signal(6)
self.specials += [
MultiReg(self.tx_idle, tx_idle, "serdes"),
MultiReg(self.tx_comma, tx_comma, "serdes"),
MultiReg(rx_idle, self.rx_idle, "sys"),
MultiReg(rx_comma, self.rx_comma, "sys")
]
self.specials += MultiReg(self.rx_bitslip_value, rx_bitslip_value, "serdes"),
# tx clock (linerate/10)
if mode == "master":
self.submodules.tx_clk_gearbox = Gearbox(40, "serdes", 8, "serdes_5x")
self.comb += self.tx_clk_gearbox.i.eq((0b1111100000 << 30) |
(0b1111100000 << 20) |
(0b1111100000 << 10) |
(0b1111100000 << 0))
clk_o = Signal()
self.specials += [
Instance("OSERDESE2",
p_DATA_WIDTH=8, p_TRISTATE_WIDTH=1,
p_DATA_RATE_OQ="DDR", p_DATA_RATE_TQ="BUF",
p_SERDES_MODE="MASTER",
o_OQ=clk_o,
i_OCE=1,
i_RST=ResetSignal("serdes"),
i_CLK=ClockSignal("serdes_20x"), i_CLKDIV=ClockSignal("serdes_5x"),
i_D1=self.tx_clk_gearbox.o[0], i_D2=self.tx_clk_gearbox.o[1],
i_D3=self.tx_clk_gearbox.o[2], i_D4=self.tx_clk_gearbox.o[3],
i_D5=self.tx_clk_gearbox.o[4], i_D6=self.tx_clk_gearbox.o[5],
i_D7=self.tx_clk_gearbox.o[6], i_D8=self.tx_clk_gearbox.o[7]
),
Instance("OBUFDS",
i_I=clk_o,
o_O=pads.clk_p,
o_OB=pads.clk_n
)
]
# tx datapath
# tx_data -> encoders -> gearbox -> serdes
self.submodules.tx_gearbox = Gearbox(40, "serdes", 8, "serdes_5x")
self.comb += [
If(tx_comma,
self.encoder.k[0].eq(1),
self.encoder.d[0].eq(0xbc)
).Else(
self.encoder.d[0].eq(self.tx_data[0:8]),
self.encoder.d[1].eq(self.tx_data[8:16]),
self.encoder.d[2].eq(self.tx_data[16:24]),
self.encoder.d[3].eq(self.tx_data[24:32])
)
]
self.sync.serdes += \
If(tx_idle,
self.tx_gearbox.i.eq(0)
).Else(
self.tx_gearbox.i.eq(Cat(*[self.encoder.output[i] for i in range(4)]))
)
serdes_o = Signal()
self.specials += [
Instance("OSERDESE2",
p_DATA_WIDTH=8, p_TRISTATE_WIDTH=1,
p_DATA_RATE_OQ="DDR", p_DATA_RATE_TQ="BUF",
p_SERDES_MODE="MASTER",
o_OQ=serdes_o,
i_OCE=1,
i_RST=ResetSignal("serdes"),
i_CLK=ClockSignal("serdes_20x"), i_CLKDIV=ClockSignal("serdes_5x"),
i_D1=self.tx_gearbox.o[0], i_D2=self.tx_gearbox.o[1],
i_D3=self.tx_gearbox.o[2], i_D4=self.tx_gearbox.o[3],
i_D5=self.tx_gearbox.o[4], i_D6=self.tx_gearbox.o[5],
i_D7=self.tx_gearbox.o[6], i_D8=self.tx_gearbox.o[7]
),
Instance("OBUFDS",
i_I=serdes_o,
o_O=pads.tx_p,
o_OB=pads.tx_n
)
]
# rx clock
use_bufr = True
if mode == "slave":
clk_i = Signal()
clk_i_bufg = Signal()
self.specials += [
Instance("IBUFDS",
i_I=pads.clk_p,
i_IB=pads.clk_n,
o_O=clk_i
)
]
if use_bufr:
clk_i_bufr = Signal()
self.specials += [
Instance("BUFR", i_I=clk_i, o_O=clk_i_bufr),
Instance("BUFG", i_I=clk_i_bufr, o_O=clk_i_bufg)
]
else:
self.specials += Instance("BUFG", i_I=clk_i, o_O=clk_i_bufg)
self.comb += pll.refclk.eq(clk_i_bufg)
# rx datapath
# serdes -> gearbox -> bitslip -> decoders -> rx_data
self.submodules.rx_gearbox = Gearbox(8, "serdes_5x", 40, "serdes")
self.submodules.rx_bitslip = ClockDomainsRenamer("serdes")(BitSlip(40))
self.submodules.phase_detector = ClockDomainsRenamer("serdes_5x")(PhaseDetector())
# 2 serdes for phase detection: 1 master (used for data) / 1 slave
serdes_m_i_nodelay = Signal()
serdes_s_i_nodelay = Signal()
self.specials += [
Instance("IBUFDS_DIFF_OUT",
i_I=pads.rx_p,
i_IB=pads.rx_n,
o_O=serdes_m_i_nodelay,
o_OB=serdes_s_i_nodelay
)
]
serdes_m_i_delayed = Signal()
serdes_m_q = Signal(8)
self.specials += [
Instance("IDELAYE2",
p_DELAY_SRC="IDATAIN", p_SIGNAL_PATTERN="DATA",
p_CINVCTRL_SEL="FALSE", p_HIGH_PERFORMANCE_MODE="TRUE",
p_REFCLK_FREQUENCY=200.0, p_PIPE_SEL="FALSE",
p_IDELAY_TYPE="VARIABLE", p_IDELAY_VALUE=0,
i_C=ClockSignal(),
i_LD=self.rx_delay_rst,
i_CE=self.rx_delay_ce,
i_LDPIPEEN=0, i_INC=self.rx_delay_inc,
i_IDATAIN=serdes_m_i_nodelay, o_DATAOUT=serdes_m_i_delayed
),
Instance("ISERDESE2",
p_DATA_WIDTH=8, p_DATA_RATE="DDR",
p_SERDES_MODE="MASTER", p_INTERFACE_TYPE="NETWORKING",
p_NUM_CE=1, p_IOBDELAY="IFD",
i_DDLY=serdes_m_i_delayed,
i_CE1=1,
i_RST=ResetSignal("serdes"),
i_CLK=ClockSignal("serdes_20x"), i_CLKB=~ClockSignal("serdes_20x"),
i_CLKDIV=ClockSignal("serdes_5x"),
i_BITSLIP=0,
o_Q8=serdes_m_q[0], o_Q7=serdes_m_q[1],
o_Q6=serdes_m_q[2], o_Q5=serdes_m_q[3],
o_Q4=serdes_m_q[4], o_Q3=serdes_m_q[5],
o_Q2=serdes_m_q[6], o_Q1=serdes_m_q[7]
)
]
self.comb += self.phase_detector.mdata.eq(serdes_m_q)
serdes_s_i_delayed = Signal()
serdes_s_q = Signal(8)
serdes_s_idelay_value = int(1/(4*pll.linerate)/78e-12) # 1/4 bit period
assert serdes_s_idelay_value < 32
self.specials += [
Instance("IDELAYE2",
p_DELAY_SRC="IDATAIN", p_SIGNAL_PATTERN="DATA",
p_CINVCTRL_SEL="FALSE", p_HIGH_PERFORMANCE_MODE="TRUE",
p_REFCLK_FREQUENCY=200.0, p_PIPE_SEL="FALSE",
p_IDELAY_TYPE="VARIABLE", p_IDELAY_VALUE=serdes_s_idelay_value,
i_C=ClockSignal(),
i_LD=self.rx_delay_rst,
i_CE=self.rx_delay_ce,
i_LDPIPEEN=0, i_INC=self.rx_delay_inc,
i_IDATAIN=serdes_s_i_nodelay, o_DATAOUT=serdes_s_i_delayed
),
Instance("ISERDESE2",
p_DATA_WIDTH=8, p_DATA_RATE="DDR",
p_SERDES_MODE="MASTER", p_INTERFACE_TYPE="NETWORKING",
p_NUM_CE=1, p_IOBDELAY="IFD",
i_DDLY=serdes_s_i_delayed,
i_CE1=1,
i_RST=ResetSignal("serdes"),
i_CLK=ClockSignal("serdes_20x"), i_CLKB=~ClockSignal("serdes_20x"),
i_CLKDIV=ClockSignal("serdes_5x"),
i_BITSLIP=0,
o_Q8=serdes_s_q[0], o_Q7=serdes_s_q[1],
o_Q6=serdes_s_q[2], o_Q5=serdes_s_q[3],
o_Q4=serdes_s_q[4], o_Q3=serdes_s_q[5],
o_Q2=serdes_s_q[6], o_Q1=serdes_s_q[7]
)
]
self.comb += self.phase_detector.sdata.eq(~serdes_s_q)
self.comb += [
self.rx_gearbox.i.eq(serdes_m_q),
self.rx_bitslip.value.eq(rx_bitslip_value),
self.rx_bitslip.i.eq(self.rx_gearbox.o),
self.decoders[0].input.eq(self.rx_bitslip.o[0:10]),
self.decoders[1].input.eq(self.rx_bitslip.o[10:20]),
self.decoders[2].input.eq(self.rx_bitslip.o[20:30]),
self.decoders[3].input.eq(self.rx_bitslip.o[30:40]),
self.rx_data.eq(Cat(*[self.decoders[i].d for i in range(4)])),
rx_idle.eq(self.rx_bitslip.o == 0),
rx_comma.eq(((self.decoders[0].d == 0xbc) & (self.decoders[0].k == 1)) &
((self.decoders[1].d == 0x00) & (self.decoders[1].k == 0)) &
((self.decoders[2].d == 0x00) & (self.decoders[2].k == 0)) &
((self.decoders[3].d == 0x00) & (self.decoders[3].k == 0)))
]