src/mem/bus.cc

   1 /*
   2  * Copyright (c) 2006 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
  29 /**
  30  * @file Definition of a bus object.
  31  */
  32
  33
  34 #include "base/trace.hh"
  35 #include "mem/bus.hh"
  36 #include "sim/builder.hh"
  37
  38 /** Get the ranges of anyone that we are connected to. */
  39 void
  40 Bus::init()
  41 {
  42     std::vector<Port*>::iterator intIter;
  43     for (intIter = interfaces.begin(); intIter != interfaces.end(); intIter++)
  44         (*intIter)->sendStatusChange(Port::RangeChange);
  45 }
  46
  47
  48 /** Function called by the port when the bus is recieving a Timing
  49  * transaction.*/
  50 bool
  51 Bus::recvTiming(Packet *pkt)
  52 {
  53     Port *port;
  54     if (pkt->dest == Packet::Broadcast) {
  55         port = findPort(pkt->addr, pkt->src);
  56     } else {
  57         assert(pkt->dest >= 0 && pkt->dest < interfaces.size());
  58         assert(pkt->dest != pkt->src); // catch infinite loops
  59         port = interfaces[pkt->dest];
  60     }
  61     return port->sendTiming(pkt);
  62 }
  63
  64 Port *
  65 Bus::findPort(Addr addr, int id)
  66 {
  67     /* An interval tree would be a better way to do this. --ali. */
  68     int dest_id = -1;
  69     int i = 0;
  70     bool found = false;
  71
  72     while (i < portList.size() && !found)
  73     {
  74         if (portList[i].range == addr) {
  75             dest_id = portList[i].portId;
  76             found = true;
  77             DPRINTF(Bus, "Found Addr: %llx on device %d\n", addr, dest_id);
  78         }
  79         i++;
  80     }
  81     if (dest_id == -1)
  82         panic("Unable to find destination for addr: %llx", addr);
  83
  84     // we shouldn't be sending this back to where it came from
  85     assert(dest_id != id);
  86
  87     return interfaces[dest_id];
  88 }
  89
  90 /** Function called by the port when the bus is recieving a Atomic
  91  * transaction.*/
  92 Tick
  93 Bus::recvAtomic(Packet *pkt)
  94 {
  95     assert(pkt->dest == Packet::Broadcast);
  96     return findPort(pkt->addr, pkt->src)->sendAtomic(pkt);
  97 }
  98
  99 /** Function called by the port when the bus is recieving a Functional
 100  * transaction.*/
 101 void
 102 Bus::recvFunctional(Packet *pkt)
 103 {
 104     assert(pkt->dest == Packet::Broadcast);
 105     findPort(pkt->addr, pkt->src)->sendFunctional(pkt);
 106 }
 107
 108 /** Function called by the port when the bus is recieving a status change.*/
 109 void
 110 Bus::recvStatusChange(Port::Status status, int id)
 111 {
 112     DPRINTF(Bus, "Bus %d recieved status change from device id %d\n",
 113             busId, id);
 114     assert(status == Port::RangeChange &&
 115            "The other statuses need to be implemented.");
 116
 117     assert(id < interfaces.size() && id >= 0);
 118     int x;
 119     Port *port = interfaces[id];
 120     AddrRangeList ranges;
 121     AddrRangeList snoops;
 122     AddrRangeIter iter;
 123     std::vector<DevMap>::iterator portIter;
 124
 125     // Clean out any previously existent ids
 126     for (portIter = portList.begin(); portIter != portList.end(); ) {
 127         if (portIter->portId == id)
 128             portIter = portList.erase(portIter);
 129         else
 130             portIter++;
 131     }
 132
 133     port->getPeerAddressRanges(ranges, snoops);
 134
 135     // not dealing with snooping yet either
 136     assert(snoops.size() == 0);
 137     for(iter = ranges.begin(); iter != ranges.end(); iter++) {
 138         DevMap dm;
 139         dm.portId = id;
 140         dm.range = *iter;
 141
 142         DPRINTF(MMU, "Adding range %llx - %llx for id %d\n", dm.range.start,
 143                 dm.range.end, id);
 144         portList.push_back(dm);
 145     }
 146     DPRINTF(MMU, "port list has %d entries\n", portList.size());
 147
 148     // tell all our peers that our address range has changed.
 149     // Don't tell the device that caused this change, it already knows
 150     for (x = 0; x < interfaces.size(); x++)
 151         if (x != id)
 152             interfaces[x]->sendStatusChange(Port::RangeChange);
 153 }
 154
 155 void
 156 Bus::addressRanges(AddrRangeList &resp, AddrRangeList &snoop, int id)
 157 {
 158     std::vector<DevMap>::iterator portIter;
 159
 160     resp.clear();
 161     snoop.clear();
 162
 163     DPRINTF(Bus, "Bus id %d recieved address range request returning\n",
 164             busId);
 165     for (portIter = portList.begin(); portIter != portList.end(); portIter++) {
 166         if (portIter->portId != id) {
 167             resp.push_back(portIter->range);
 168             DPRINTF(Bus, "-- %#llX : %#llX\n", portIter->range.start,
 169                     portIter->range.end);
 170         }
 171     }
 172 }
 173
 174 BEGIN_DECLARE_SIM_OBJECT_PARAMS(Bus)
 175
 176     Param<int> bus_id;
 177
 178 END_DECLARE_SIM_OBJECT_PARAMS(Bus)
 179
 180 BEGIN_INIT_SIM_OBJECT_PARAMS(Bus)
 181     INIT_PARAM(bus_id, "a globally unique bus id")
 182 END_INIT_SIM_OBJECT_PARAMS(Bus)
 183
 184 CREATE_SIM_OBJECT(Bus)
 185 {
 186     return new Bus(getInstanceName(), bus_id);
 187 }
 188
 189 REGISTER_SIM_OBJECT("Bus", Bus)