src/dev/etherlink.cc

   1 /*
   2  * Copyright (c) 2002-2005 The Regents of The University of Michigan
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are
   7  * met: redistributions of source code must retain the above copyright
   8  * notice, this list of conditions and the following disclaimer;
   9  * redistributions in binary form must reproduce the above copyright
  10  * notice, this list of conditions and the following disclaimer in the
  11  * documentation and/or other materials provided with the distribution;
  12  * neither the name of the copyright holders nor the names of its
  13  * contributors may be used to endorse or promote products derived from
  14  * this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  17  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  18  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  19  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  20  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  21  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  22  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  26  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  *
  28  * Authors: Nathan Binkert
  29  *          Ron Dreslinski
  30  */
  31
  32 /* @file
  33  * Device module for modelling a fixed bandwidth full duplex ethernet link
  34  */
  35
  36 #include <cmath>
  37 #include <deque>
  38 #include <string>
  39 #include <vector>
  40
  41 #include "base/random.hh"
  42 #include "base/trace.hh"
  43 #include "dev/etherdump.hh"
  44 #include "dev/etherint.hh"
  45 #include "dev/etherlink.hh"
  46 #include "dev/etherpkt.hh"
  47 #include "params/EtherLink.hh"
  48 #include "sim/serialize.hh"
  49 #include "sim/system.hh"
  50 #include "sim/core.hh"
  51
  52 using namespace std;
  53
  54 EtherLink::EtherLink(const Params *p)
  55     : EtherObject(p)
  56 {
  57     link[0] = new Link(name() + ".link0", this, 0, p->speed,
  58                        p->delay, p->delay_var, p->dump);
  59     link[1] = new Link(name() + ".link1", this, 1, p->speed,
  60                        p->delay, p->delay_var, p->dump);
  61
  62     interface[0] = new Interface(name() + ".int0", link[0], link[1]);
  63     interface[1] = new Interface(name() + ".int1", link[1], link[0]);
  64 }
  65
  66
  67 EtherLink::~EtherLink()
  68 {
  69     delete link[0];
  70     delete link[1];
  71
  72     delete interface[0];
  73     delete interface[1];
  74 }
  75
  76 EtherInt*
  77 EtherLink::getEthPort(const std::string &if_name, int idx)
  78 {
  79     Interface *i;
  80     if (if_name == "int0")
  81         i = interface[0];
  82     else if (if_name == "int1")
  83         i = interface[1];
  84     else
  85         return NULL;
  86     if (i->getPeer())
  87         panic("interface already connected to\n");
  88
  89     return i;
  90 }
  91
  92
  93 EtherLink::Interface::Interface(const string &name, Link *tx, Link *rx)
  94     : EtherInt(name), txlink(tx)
  95 {
  96     tx->setTxInt(this);
  97     rx->setRxInt(this);
  98 }
  99
 100 EtherLink::Link::Link(const string &name, EtherLink *p, int num,
 101                       double rate, Tick delay, Tick delay_var, EtherDump *d)
 102     : objName(name), parent(p), number(num), txint(NULL), rxint(NULL),
 103       ticksPerByte(rate), linkDelay(delay), delayVar(delay_var), dump(d),
 104       doneEvent(this)
 105 { }
 106
 107 void
 108 EtherLink::serialize(ostream &os)
 109 {
 110     link[0]->serialize("link0", os);
 111     link[1]->serialize("link1", os);
 112 }
 113
 114 void
 115 EtherLink::unserialize(Checkpoint *cp, const string &section)
 116 {
 117     link[0]->unserialize("link0", cp, section);
 118     link[1]->unserialize("link1", cp, section);
 119 }
 120
 121 void
 122 EtherLink::Link::txComplete(EthPacketPtr packet)
 123 {
 124     DPRINTF(Ethernet, "packet received: len=%d\n", packet->length);
 125     DDUMP(EthernetData, packet->data, packet->length);
 126     rxint->sendPacket(packet);
 127 }
 128
 129 class LinkDelayEvent : public Event
 130 {
 131   protected:
 132     EtherLink::Link *link;
 133     EthPacketPtr packet;
 134
 135   public:
 136     // non-scheduling version for createForUnserialize()
 137     LinkDelayEvent();
 138     LinkDelayEvent(EtherLink::Link *link, EthPacketPtr pkt, Tick when);
 139
 140     void process();
 141
 142     virtual void serialize(ostream &os);
 143     virtual void unserialize(Checkpoint *cp, const string &section);
 144     static Serializable *createForUnserialize(Checkpoint *cp,
 145                                               const string &section);
 146 };
 147
 148 void
 149 EtherLink::Link::txDone()
 150 {
 151     if (dump)
 152         dump->dump(packet);
 153
 154     if (linkDelay > 0) {
 155         DPRINTF(Ethernet, "packet delayed: delay=%d\n", linkDelay);
 156         new LinkDelayEvent(this, packet, curTick + linkDelay);
 157     } else {
 158         txComplete(packet);
 159     }
 160
 161     packet = 0;
 162     assert(!busy());
 163
 164     txint->sendDone();
 165 }
 166
 167 bool
 168 EtherLink::Link::transmit(EthPacketPtr pkt)
 169 {
 170     if (busy()) {
 171         DPRINTF(Ethernet, "packet not sent, link busy\n");
 172         return false;
 173     }
 174
 175     DPRINTF(Ethernet, "packet sent: len=%d\n", pkt->length);
 176     DDUMP(EthernetData, pkt->data, pkt->length);
 177
 178     packet = pkt;
 179     Tick delay = (Tick)ceil(((double)pkt->length * ticksPerByte) + 1.0);
 180     if (delayVar != 0)
 181         delay += random_mt.random<Tick>(0, delayVar);
 182
 183     DPRINTF(Ethernet, "scheduling packet: delay=%d, (rate=%f)\n",
 184             delay, ticksPerByte);
 185     doneEvent.schedule(curTick + delay);
 186
 187     return true;
 188 }
 189
 190 void
 191 EtherLink::Link::serialize(const string &base, ostream &os)
 192 {
 193     bool packet_exists = packet;
 194     paramOut(os, base + ".packet_exists", packet_exists);
 195     if (packet_exists)
 196         packet->serialize(base + ".packet", os);
 197
 198     bool event_scheduled = doneEvent.scheduled();
 199     paramOut(os, base + ".event_scheduled", event_scheduled);
 200     if (event_scheduled) {
 201         Tick event_time = doneEvent.when();
 202         paramOut(os, base + ".event_time", event_time);
 203     }
 204
 205 }
 206
 207 void
 208 EtherLink::Link::unserialize(const string &base, Checkpoint *cp,
 209                              const string &section)
 210 {
 211     bool packet_exists;
 212     paramIn(cp, section, base + ".packet_exists", packet_exists);
 213     if (packet_exists) {
 214         packet = new EthPacketData(16384);
 215         packet->unserialize(base + ".packet", cp, section);
 216     }
 217
 218     bool event_scheduled;
 219     paramIn(cp, section, base + ".event_scheduled", event_scheduled);
 220     if (event_scheduled) {
 221         Tick event_time;
 222         paramIn(cp, section, base + ".event_time", event_time);
 223         doneEvent.schedule(event_time);
 224     }
 225 }
 226
 227 LinkDelayEvent::LinkDelayEvent()
 228     : Event(&mainEventQueue), link(NULL)
 229 {
 230     setFlags(AutoSerialize);
 231     setFlags(AutoDelete);
 232 }
 233
 234 LinkDelayEvent::LinkDelayEvent(EtherLink::Link *l, EthPacketPtr p, Tick when)
 235     : Event(&mainEventQueue), link(l), packet(p)
 236 {
 237     setFlags(AutoSerialize);
 238     setFlags(AutoDelete);
 239     schedule(when);
 240 }
 241
 242 void
 243 LinkDelayEvent::process()
 244 {
 245     link->txComplete(packet);
 246 }
 247
 248 void
 249 LinkDelayEvent::serialize(ostream &os)
 250 {
 251     paramOut(os, "type", string("LinkDelayEvent"));
 252     Event::serialize(os);
 253
 254     EtherLink *parent = link->parent;
 255     bool number = link->number;
 256     SERIALIZE_OBJPTR(parent);
 257     SERIALIZE_SCALAR(number);
 258
 259     packet->serialize("packet", os);
 260 }
 261
 262
 263 void
 264 LinkDelayEvent::unserialize(Checkpoint *cp, const string &section)
 265 {
 266     Event::unserialize(cp, section);
 267
 268     EtherLink *parent;
 269     bool number;
 270     UNSERIALIZE_OBJPTR(parent);
 271     UNSERIALIZE_SCALAR(number);
 272
 273     link = parent->link[number];
 274
 275     packet = new EthPacketData(16384);
 276     packet->unserialize("packet", cp, section);
 277 }
 278
 279
 280 Serializable *
 281 LinkDelayEvent::createForUnserialize(Checkpoint *cp, const string &section)
 282 {
 283     return new LinkDelayEvent();
 284 }
 285
 286 REGISTER_SERIALIZEABLE("LinkDelayEvent", LinkDelayEvent)
 287
 288 EtherLink *
 289 EtherLinkParams::create()
 290 {
 291     return new EtherLink(this);
 292 }