xbar.cc revision 2982
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 * Authors: Ali Saidi 29 */ 30 31/** 32 * @file 33 * Definition of a bus object. 34 */ 35 36 37#include "base/misc.hh" 38#include "base/trace.hh" 39#include "mem/bus.hh" 40#include "sim/builder.hh" 41 42Port * 43Bus::getPort(const std::string &if_name, int idx) 44{ 45 if (if_name == "default") 46 if (defaultPort == NULL) { 47 defaultPort = new BusPort(csprintf("%s-default",name()), this, 48 defaultId); 49 return defaultPort; 50 } else 51 fatal("Default port already set\n"); 52 53 // if_name ignored? forced to be empty? 54 int id = interfaces.size(); 55 BusPort *bp = new BusPort(csprintf("%s-p%d", name(), id), this, id); 56 interfaces.push_back(bp); 57 return bp; 58} 59 60/** Get the ranges of anyone other buses that we are connected to. */ 61void 62Bus::init() 63{ 64 std::vector<Port*>::iterator intIter; 65 66 for (intIter = interfaces.begin(); intIter != interfaces.end(); intIter++) 67 (*intIter)->sendStatusChange(Port::RangeChange); 68} 69 70 71/** Function called by the port when the bus is receiving a Timing 72 * transaction.*/ 73bool 74Bus::recvTiming(Packet *pkt) 75{ 76 Port *port; 77 DPRINTF(Bus, "recvTiming: packet src %d dest %d addr 0x%x cmd %s\n", 78 pkt->getSrc(), pkt->getDest(), pkt->getAddr(), pkt->cmdString()); 79 80 short dest = pkt->getDest(); 81 if (dest == Packet::Broadcast) { 82 port = findPort(pkt->getAddr(), pkt->getSrc()); 83 } else { 84 assert(dest >= 0 && dest < interfaces.size()); 85 assert(dest != pkt->getSrc()); // catch infinite loops 86 port = interfaces[dest]; 87 } 88 if (port->sendTiming(pkt)) { 89 // packet was successfully sent, just return true. 90 return true; 91 } 92 93 // packet not successfully sent 94 retryList.push_back(interfaces[pkt->getSrc()]); 95 return false; 96} 97 98void 99Bus::recvRetry(int id) 100{ 101 // Go through all the elements on the list calling sendRetry on each 102 // This is not very efficient at all but it works. Ultimately we should end 103 // up with something that is more intelligent. 104 int initialSize = retryList.size(); 105 int i; 106 Port *p; 107 108 for (i = 0; i < initialSize; i++) { 109 assert(retryList.size() > 0); 110 p = retryList.front(); 111 retryList.pop_front(); 112 p->sendRetry(); 113 } 114} 115 116 117Port * 118Bus::findPort(Addr addr, int id) 119{ 120 /* An interval tree would be a better way to do this. --ali. */ 121 int dest_id = -1; 122 int i = 0; 123 bool found = false; 124 AddrRangeIter iter; 125 126 while (i < portList.size() && !found) 127 { 128 if (portList[i].range == addr) { 129 dest_id = portList[i].portId; 130 found = true; 131 DPRINTF(Bus, " found addr 0x%llx on device %d\n", addr, dest_id); 132 } 133 i++; 134 } 135 136 // Check if this matches the default range 137 if (dest_id == -1) { 138 for (iter = defaultRange.begin(); iter != defaultRange.end(); iter++) { 139 if (*iter == addr) { 140 DPRINTF(Bus, " found addr 0x%llx on default\n", addr); 141 return defaultPort; 142 } 143 } 144 panic("Unable to find destination for addr: %llx", addr); 145 } 146 147 148 // we shouldn't be sending this back to where it came from 149 assert(dest_id != id); 150 151 return interfaces[dest_id]; 152} 153 154/** Function called by the port when the bus is receiving a Atomic 155 * transaction.*/ 156Tick 157Bus::recvAtomic(Packet *pkt) 158{ 159 DPRINTF(Bus, "recvAtomic: packet src %d dest %d addr 0x%x cmd %s\n", 160 pkt->getSrc(), pkt->getDest(), pkt->getAddr(), pkt->cmdString()); 161 assert(pkt->getDest() == Packet::Broadcast); 162 return findPort(pkt->getAddr(), pkt->getSrc())->sendAtomic(pkt); 163} 164 165/** Function called by the port when the bus is receiving a Functional 166 * transaction.*/ 167void 168Bus::recvFunctional(Packet *pkt) 169{ 170 DPRINTF(Bus, "recvFunctional: packet src %d dest %d addr 0x%x cmd %s\n", 171 pkt->getSrc(), pkt->getDest(), pkt->getAddr(), pkt->cmdString()); 172 assert(pkt->getDest() == Packet::Broadcast); 173 findPort(pkt->getAddr(), pkt->getSrc())->sendFunctional(pkt); 174} 175 176/** Function called by the port when the bus is receiving a status change.*/ 177void 178Bus::recvStatusChange(Port::Status status, int id) 179{ 180 AddrRangeList ranges; 181 AddrRangeList snoops; 182 int x; 183 AddrRangeIter iter; 184 185 assert(status == Port::RangeChange && 186 "The other statuses need to be implemented."); 187 188 DPRINTF(BusAddrRanges, "received RangeChange from device id %d\n", id); 189 190 if (id == defaultId) { 191 defaultRange.clear(); 192 defaultPort->getPeerAddressRanges(ranges, snoops); 193 assert(snoops.size() == 0); 194 for(iter = ranges.begin(); iter != ranges.end(); iter++) { 195 defaultRange.push_back(*iter); 196 DPRINTF(BusAddrRanges, "Adding range %llx - %llx for default\n", 197 iter->start, iter->end); 198 } 199 } else { 200 201 assert((id < interfaces.size() && id >= 0) || id == -1); 202 Port *port = interfaces[id]; 203 std::vector<DevMap>::iterator portIter; 204 205 // Clean out any previously existent ids 206 for (portIter = portList.begin(); portIter != portList.end(); ) { 207 if (portIter->portId == id) 208 portIter = portList.erase(portIter); 209 else 210 portIter++; 211 } 212 213 port->getPeerAddressRanges(ranges, snoops); 214 215 // not dealing with snooping yet either 216 assert(snoops.size() == 0); 217 for(iter = ranges.begin(); iter != ranges.end(); iter++) { 218 DevMap dm; 219 dm.portId = id; 220 dm.range = *iter; 221 222 DPRINTF(BusAddrRanges, "Adding range %llx - %llx for id %d\n", 223 dm.range.start, dm.range.end, id); 224 portList.push_back(dm); 225 } 226 } 227 DPRINTF(MMU, "port list has %d entries\n", portList.size()); 228 229 // tell all our peers that our address range has changed. 230 // Don't tell the device that caused this change, it already knows 231 for (x = 0; x < interfaces.size(); x++) 232 if (x != id) 233 interfaces[x]->sendStatusChange(Port::RangeChange); 234 235 if (id != defaultId && defaultPort) 236 defaultPort->sendStatusChange(Port::RangeChange); 237} 238 239void 240Bus::addressRanges(AddrRangeList &resp, AddrRangeList &snoop, int id) 241{ 242 std::vector<DevMap>::iterator portIter; 243 AddrRangeIter dflt_iter; 244 bool subset; 245 246 resp.clear(); 247 snoop.clear(); 248 249 DPRINTF(BusAddrRanges, "received address range request, returning:\n"); 250 251 for (dflt_iter = defaultRange.begin(); dflt_iter != defaultRange.end(); 252 dflt_iter++) { 253 resp.push_back(*dflt_iter); 254 DPRINTF(BusAddrRanges, " -- %#llX : %#llX\n",dflt_iter->start, 255 dflt_iter->end); 256 } 257 for (portIter = portList.begin(); portIter != portList.end(); portIter++) { 258 subset = false; 259 for (dflt_iter = defaultRange.begin(); dflt_iter != defaultRange.end(); 260 dflt_iter++) { 261 if ((portIter->range.start < dflt_iter->start && 262 portIter->range.end >= dflt_iter->start) || 263 (portIter->range.start < dflt_iter->end && 264 portIter->range.end >= dflt_iter->end)) 265 fatal("Devices can not set ranges that itersect the default set\ 266 but are not a subset of the default set.\n"); 267 if (portIter->range.start >= dflt_iter->start && 268 portIter->range.end <= dflt_iter->end) { 269 subset = true; 270 DPRINTF(BusAddrRanges, " -- %#llX : %#llX is a SUBSET\n", 271 portIter->range.start, portIter->range.end); 272 } 273 } 274 if (portIter->portId != id && !subset) { 275 resp.push_back(portIter->range); 276 DPRINTF(BusAddrRanges, " -- %#llX : %#llX\n", 277 portIter->range.start, portIter->range.end); 278 } 279 } 280} 281 282BEGIN_DECLARE_SIM_OBJECT_PARAMS(Bus) 283 284 Param<int> bus_id; 285 286END_DECLARE_SIM_OBJECT_PARAMS(Bus) 287 288BEGIN_INIT_SIM_OBJECT_PARAMS(Bus) 289 INIT_PARAM(bus_id, "a globally unique bus id") 290END_INIT_SIM_OBJECT_PARAMS(Bus) 291 292CREATE_SIM_OBJECT(Bus) 293{ 294 return new Bus(getInstanceName(), bus_id); 295} 296 297REGISTER_SIM_OBJECT("Bus", Bus) 298