litex/liteeth/core/ip/__init__.py

181 lines
5.5 KiB
Python

from liteeth.common import *
from liteeth.generic import *
from liteeth.core.ip.checksum import *
from liteeth.core.ip.crossbar import *
from liteeth.generic.depacketizer import LiteEthDepacketizer
from liteeth.generic.packetizer import LiteEthPacketizer
class LiteEthIPV4Packetizer(LiteEthPacketizer):
def __init__(self):
LiteEthPacketizer.__init__(self,
eth_ipv4_description(8),
eth_mac_description(8),
ipv4_header,
ipv4_header_len)
class LiteEthIPTX(Module):
def __init__(self, mac_address, ip_address, arp_table):
self.sink = sink = Sink(eth_ipv4_user_description(8))
self.source = source = Source(eth_mac_description(8))
self.target_unreachable = Signal()
###
self.submodules.checksum = checksum = LiteEthIPV4Checksum(skip_checksum=True)
self.comb += [
checksum.ce.eq(sink.stb & sink.sop),
checksum.reset.eq(source.stb & source.eop & source.ack)
]
self.submodules.packetizer = packetizer = LiteEthIPV4Packetizer()
self.comb += [
packetizer.sink.stb.eq(sink.stb & checksum.done),
packetizer.sink.sop.eq(sink.sop),
packetizer.sink.eop.eq(sink.eop),
sink.ack.eq(packetizer.sink.ack & checksum.done),
packetizer.sink.target_ip.eq(sink.ip_address),
packetizer.sink.protocol.eq(sink.protocol),
packetizer.sink.total_length.eq(sink.length + (0x5*4)),
packetizer.sink.version.eq(0x4), # ipv4
packetizer.sink.ihl.eq(0x5), # 20 bytes
packetizer.sink.identification.eq(0),
packetizer.sink.ttl.eq(0x80),
packetizer.sink.sender_ip.eq(ip_address),
packetizer.sink.data.eq(sink.data),
checksum.header.eq(packetizer.header),
packetizer.sink.checksum.eq(checksum.value)
]
target_mac = Signal(48)
self.submodules.fsm = fsm = FSM(reset_state="IDLE")
fsm.act("IDLE",
packetizer.source.ack.eq(1),
If(packetizer.source.stb & packetizer.source.sop,
packetizer.source.ack.eq(0),
NextState("SEND_MAC_ADDRESS_REQUEST")
)
)
self.comb += arp_table.request.ip_address.eq(sink.ip_address)
fsm.act("SEND_MAC_ADDRESS_REQUEST",
arp_table.request.stb.eq(1),
If(arp_table.request.stb & arp_table.request.ack,
NextState("WAIT_MAC_ADDRESS_RESPONSE")
)
)
fsm.act("WAIT_MAC_ADDRESS_RESPONSE",
If(arp_table.response.stb,
arp_table.response.ack.eq(1),
If(arp_table.response.failed,
self.target_unreachable.eq(1),
NextState("DROP"),
).Else(
NextState("SEND")
)
)
)
self.sync += \
If(arp_table.response.stb,
target_mac.eq(arp_table.response.mac_address)
)
fsm.act("SEND",
Record.connect(packetizer.source, source),
source.ethernet_type.eq(ethernet_type_ip),
source.target_mac.eq(target_mac),
source.sender_mac.eq(mac_address),
If(source.stb & source.eop & source.ack,
NextState("IDLE")
)
)
fsm.act("DROP",
packetizer.source.ack.eq(1),
If(packetizer.source.stb & packetizer.source.eop & packetizer.source.ack,
NextState("IDLE")
)
)
class LiteEthIPV4Depacketizer(LiteEthDepacketizer):
def __init__(self):
LiteEthDepacketizer.__init__(self,
eth_mac_description(8),
eth_ipv4_description(8),
ipv4_header,
ipv4_header_len)
class LiteEthIPRX(Module):
def __init__(self, mac_address, ip_address):
self.sink = sink = Sink(eth_mac_description(8))
self.source = source = Source(eth_ipv4_user_description(8))
###
self.submodules.depacketizer = depacketizer = LiteEthIPV4Depacketizer()
self.comb += Record.connect(sink, depacketizer.sink)
self.submodules.checksum = checksum = LiteEthIPV4Checksum(skip_checksum=False)
self.comb += [
checksum.header.eq(depacketizer.header),
checksum.reset.eq(depacketizer.source.stb & depacketizer.source.eop),
checksum.ce.eq(depacketizer.source.stb & depacketizer.source.sop)
]
self.submodules.fsm = fsm = FSM(reset_state="IDLE")
fsm.act("IDLE",
depacketizer.source.ack.eq(1),
If(depacketizer.source.stb & depacketizer.source.sop,
depacketizer.source.ack.eq(0),
NextState("CHECK")
)
)
valid = Signal()
self.sync += valid.eq(
depacketizer.source.stb &
(depacketizer.source.target_ip == ip_address) &
(depacketizer.source.version == 0x4) &
(depacketizer.source.ihl == 0x5) &
(checksum.value == 0)
)
fsm.act("CHECK",
If(checksum.done,
If(valid,
NextState("PRESENT")
).Else(
NextState("DROP")
)
)
)
self.comb += [
source.sop.eq(depacketizer.source.sop),
source.eop.eq(depacketizer.source.eop),
source.length.eq(depacketizer.source.total_length - (0x5*4)),
source.protocol.eq(depacketizer.source.protocol),
source.ip_address.eq(depacketizer.source.sender_ip),
source.data.eq(depacketizer.source.data),
source.error.eq(depacketizer.source.error)
]
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 LiteEthIP(Module):
def __init__(self, mac, mac_address, ip_address, arp_table):
self.submodules.tx = tx = LiteEthIPTX(mac_address, ip_address, arp_table)
self.submodules.rx = rx = LiteEthIPRX(mac_address, ip_address)
mac_port = mac.crossbar.get_port(ethernet_type_ip)
self.comb += [
Record.connect(tx.source, mac_port.sink),
Record.connect(mac_port.source, rx.sink)
]
self.submodules.crossbar = crossbar = LiteEthIPV4Crossbar()
self.comb += [
Record.connect(crossbar.master.source, tx.sink),
Record.connect(rx.source, crossbar.master.sink)
]