liteeth/core/udp/__init__.py

   1 from liteeth.common import *
   2 from liteeth.generic.depacketizer import LiteEthDepacketizer
   3 from liteeth.generic.packetizer import LiteEthPacketizer
   4
   5 class LiteEthUDPDepacketizer(LiteEthDepacketizer):
   6         def __init__(self):
   7                 LiteEthDepacketizer.__init__(self,
   8                         eth_ipv4_user_description(8),
   9                         eth_udp_description(8),
  10                         udp_header,
  11                         udp_header_len)
  12
  13 class LiteEthUDPPacketizer(LiteEthPacketizer):
  14         def __init__(self):
  15                 LiteEthPacketizer.__init__(self,
  16                         eth_udp_description(8),
  17                         eth_ipv4_user_description(8),
  18                         udp_header,
  19                         udp_header_len)
  20
  21 class LiteEthUDPTX(Module):
  22         def __init__(self, ip_address):
  23                 self.sink = Sink(eth_udp_user_description(8))
  24                 self.source = Source(eth_ipv4_user_description(8))
  25                 ###
  26                 packetizer = LiteEthUDPPacketizer()
  27                 self.submodules += packetizer
  28                 self.comb += [
  29                         packetizer.sink.stb.eq(self.sink.stb),
  30                         packetizer.sink.sop.eq(self.sink.sop),
  31                         packetizer.sink.eop.eq(self.sink.eop),
  32                         self.sink.ack.eq(packetizer.sink.ack),
  33                         packetizer.sink.src_port.eq(self.sink.src_port),
  34                         packetizer.sink.dst_port.eq(self.sink.dst_port),
  35                         packetizer.sink.length.eq(self.sink.length + udp_header_len),
  36                         packetizer.sink.checksum.eq(0),
  37                         packetizer.sink.data.eq(self.sink.data)
  38                 ]
  39                 sink = packetizer.source
  40
  41                 self.submodules.fsm = fsm = FSM(reset_state="IDLE")
  42                 fsm.act("IDLE",
  43                         sink.ack.eq(1),
  44                         If(sink.stb & sink.sop,
  45                                 sink.ack.eq(0),
  46                                 NextState("SEND")
  47                         )
  48                 )
  49                 fsm.act("SEND",
  50                         Record.connect(packetizer.source, self.source),
  51                         self.source.length.eq(packetizer.sink.length + ipv4_header_len),
  52                         self.source.protocol.eq(udp_protocol),
  53                         self.source.ip_address.eq(self.sink.ip_address),
  54                         If(self.source.stb & self.source.eop & self.source.ack,
  55                                 NextState("IDLE")
  56                         )
  57                 )
  58
  59 class LiteEthUDPRX(Module):
  60         def __init__(self, ip_address):
  61                 self.sink = Sink(eth_ipv4_user_description(8))
  62                 self.source = source = Source(eth_udp_user_description(8))
  63                 ###
  64                 depacketizer = LiteEthUDPDepacketizer()
  65                 self.submodules += depacketizer
  66                 self.comb += Record.connect(self.sink, depacketizer.sink)
  67                 sink = depacketizer.source
  68
  69                 self.submodules.fsm = fsm = FSM(reset_state="IDLE")
  70                 fsm.act("IDLE",
  71                         sink.ack.eq(1),
  72                         If(sink.stb & sink.sop,
  73                                 sink.ack.eq(0),
  74                                 NextState("CHECK")
  75                         )
  76                 )
  77                 valid = Signal()
  78                 self.comb += valid.eq(
  79                         sink.stb &
  80                         (self.sink.protocol == udp_protocol)
  81                 )
  82
  83                 fsm.act("CHECK",
  84                         If(valid,
  85                                 NextState("PRESENT")
  86                         ).Else(
  87                                 NextState("DROP")
  88                         )
  89                 )
  90                 self.comb += [
  91                         source.sop.eq(sink.sop),
  92                         source.eop.eq(sink.eop),
  93                         source.src_port.eq(sink.src_port),
  94                         source.dst_port.eq(sink.dst_port),
  95                         source.ip_address.eq(0),
  96                         source.length.eq(sink.length - udp_header_len),
  97                         source.data.eq(sink.data),
  98                         source.error.eq(sink.error)
  99                 ]
 100                 fsm.act("PRESENT",
 101                         source.stb.eq(sink.stb),
 102                         sink.ack.eq(source.ack),
 103                         If(source.stb & source.eop & source.ack,
 104                                 NextState("IDLE")
 105                         )
 106                 )
 107                 fsm.act("DROP",
 108                         sink.ack.eq(1),
 109                         If(sink.stb & sink.eop & sink.ack,
 110                                 NextState("IDLE")
 111                         )
 112                 )
 113
 114 class LiteEthUDP(Module):
 115         def __init__(self, ip, ip_address):
 116                 self.submodules.tx = LiteEthUDPTX(ip_address)
 117                 self.submodules.rx = LiteEthUDPRX(ip_address)
 118                 ip_port = ip.crossbar.get_port(udp_protocol)
 119                 self.comb += [
 120                         Record.connect(self.tx.source, ip_port.sink),
 121                         Record.connect(ip_port.source, self.rx.sink)
 122                 ]
 123                 self.sink, self.source = self.tx.sink, self.rx.source