tport.cc revision 4870
12292SN/A/* 28948Sandreas.hansson@arm.com * Copyright (c) 2006 The Regents of The University of Michigan 38707Sandreas.hansson@arm.com * All rights reserved. 48707Sandreas.hansson@arm.com * 58707Sandreas.hansson@arm.com * Redistribution and use in source and binary forms, with or without 68707Sandreas.hansson@arm.com * modification, are permitted provided that the following conditions are 78707Sandreas.hansson@arm.com * met: redistributions of source code must retain the above copyright 88707Sandreas.hansson@arm.com * notice, this list of conditions and the following disclaimer; 98707Sandreas.hansson@arm.com * redistributions in binary form must reproduce the above copyright 108707Sandreas.hansson@arm.com * notice, this list of conditions and the following disclaimer in the 118707Sandreas.hansson@arm.com * documentation and/or other materials provided with the distribution; 128707Sandreas.hansson@arm.com * neither the name of the copyright holders nor the names of its 138707Sandreas.hansson@arm.com * contributors may be used to endorse or promote products derived from 142727Sktlim@umich.edu * this software without specific prior written permission. 152292SN/A * 162292SN/A * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 172292SN/A * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 182292SN/A * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 192292SN/A * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 202292SN/A * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 212292SN/A * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 222292SN/A * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 232292SN/A * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 242292SN/A * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 252292SN/A * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 262292SN/A * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 272292SN/A * 282292SN/A * Authors: Ali Saidi 292292SN/A */ 302292SN/A 312292SN/A#include "mem/tport.hh" 322292SN/A 332292SN/Avoid 342292SN/ASimpleTimingPort::checkFunctional(PacketPtr pkt) 352292SN/A{ 362292SN/A DeferredPacketIterator i = transmitList.begin(); 372292SN/A DeferredPacketIterator end = transmitList.end(); 382292SN/A 392689Sktlim@umich.edu for (; i != end; ++i) { 402689Sktlim@umich.edu PacketPtr target = i->pkt; 412292SN/A // If the target contains data, and it overlaps the 422292SN/A // probed request, need to update data 432329SN/A if (target->intersect(pkt)) { 442980Sgblack@eecs.umich.edu if (!fixPacket(pkt, target)) { 452329SN/A // fixPacket returns true for continue, false for done 462329SN/A return; 472292SN/A } 488232Snate@binkert.org } 498232Snate@binkert.org } 508232Snate@binkert.org} 516221Snate@binkert.org 522292SN/Avoid 536221Snate@binkert.orgSimpleTimingPort::recvFunctional(PacketPtr pkt) 545529Snate@binkert.org{ 552292SN/A checkFunctional(pkt); 565529Snate@binkert.org 578707Sandreas.hansson@arm.com // Just do an atomic access and throw away the returned latency 584329Sktlim@umich.edu if (!pkt->isResponse()) 594329Sktlim@umich.edu recvAtomic(pkt); 605529Snate@binkert.org} 612907Sktlim@umich.edu 622292SN/Abool 632292SN/ASimpleTimingPort::recvTiming(PacketPtr pkt) 642292SN/A{ 652292SN/A // If the device is only a slave, it should only be sending 662980Sgblack@eecs.umich.edu // responses, which should never get nacked. There used to be 672292SN/A // code to hanldle nacks here, but I'm pretty sure it didn't work 682292SN/A // correctly with the drain code, so that would need to be fixed 692292SN/A // if we ever added it back. 702292SN/A assert(pkt->isRequest()); 712292SN/A 722292SN/A if (pkt->memInhibitAsserted()) { 732292SN/A // snooper will supply based on copy of packet 742292SN/A // still target's responsibility to delete packet 752292SN/A delete pkt->req; 762292SN/A delete pkt; 772292SN/A return true; 784329Sktlim@umich.edu } 792292SN/A 802292SN/A bool needsResponse = pkt->needsResponse(); 812292SN/A Tick latency = recvAtomic(pkt); 822292SN/A // turn packet around to go back to requester if response expected 832292SN/A if (needsResponse) { 842292SN/A // recvAtomic() should already have turned packet into 852292SN/A // atomic response 864329Sktlim@umich.edu assert(pkt->isResponse()); 872292SN/A schedSendTiming(pkt, curTick + latency); 888346Sksewell@umich.edu } else { 892292SN/A delete pkt->req; 902292SN/A delete pkt; 912292SN/A } 922292SN/A 932292SN/A return true; 942292SN/A} 952292SN/A 962292SN/A 972292SN/Avoid 982292SN/ASimpleTimingPort::schedSendTiming(PacketPtr pkt, Tick when) 992292SN/A{ 1002292SN/A assert(when > curTick); 1014329Sktlim@umich.edu 1022292SN/A // Nothing is on the list: add it and schedule an event 1038346Sksewell@umich.edu if (transmitList.empty() || when < transmitList.front().tick) { 1042292SN/A transmitList.push_front(DeferredPacket(when, pkt)); 1052292SN/A schedSendEvent(when); 1062292SN/A return; 1072292SN/A } 1082292SN/A 1092292SN/A // list is non-empty and this is not the head, so event should 1102292SN/A // already be scheduled 1116221Snate@binkert.org assert(waitingOnRetry || 1124329Sktlim@umich.edu (sendEvent->scheduled() && sendEvent->when() <= when)); 1134329Sktlim@umich.edu 1148850Sandreas.hansson@arm.com // list is non-empty & this belongs at the end 1152292SN/A if (when >= transmitList.back().tick) { 1162292SN/A transmitList.push_back(DeferredPacket(when, pkt)); 1172292SN/A return; 1182292SN/A } 1192292SN/A 1202292SN/A // this belongs in the middle somewhere 1212292SN/A DeferredPacketIterator i = transmitList.begin(); 1222292SN/A i++; // already checked for insertion at front 1232292SN/A DeferredPacketIterator end = transmitList.end(); 1242292SN/A 1252292SN/A for (; i != end; ++i) { 1262292SN/A if (when < i->tick) { 1272292SN/A transmitList.insert(i, DeferredPacket(when, pkt)); 1282727Sktlim@umich.edu return; 1292727Sktlim@umich.edu } 1302727Sktlim@umich.edu } 1316221Snate@binkert.org assert(false); // should never get here 1322727Sktlim@umich.edu} 1332727Sktlim@umich.edu 1342727Sktlim@umich.edu 1352727Sktlim@umich.eduvoid 1362727Sktlim@umich.eduSimpleTimingPort::sendDeferredPacket() 1372727Sktlim@umich.edu{ 1386221Snate@binkert.org assert(deferredPacketReady()); 1392292SN/A // take packet off list here; if recvTiming() on the other side 1402292SN/A // calls sendTiming() back on us (like SimpleTimingCpu does), then 1412292SN/A // we get confused by having a non-active packet on transmitList 1422292SN/A DeferredPacket dp = transmitList.front(); 1432292SN/A transmitList.pop_front(); 1442292SN/A bool success = sendTiming(dp.pkt); 1452307SN/A 1462307SN/A if (success) { 1472307SN/A if (!transmitList.empty() && !sendEvent->scheduled()) { 1486221Snate@binkert.org Tick time = transmitList.front().tick; 1492307SN/A sendEvent->schedule(time <= curTick ? curTick+1 : time); 1502307SN/A } 1512307SN/A 1522307SN/A if (transmitList.empty() && drainEvent) { 1532307SN/A drainEvent->process(); 1542307SN/A drainEvent = NULL; 1552307SN/A } 1562307SN/A } else { 1576221Snate@binkert.org // Unsuccessful, need to put back on transmitList. Callee 1582307SN/A // should not have messed with it (since it didn't accept that 1592307SN/A // packet), so we can just push it back on the front. 1602307SN/A assert(!sendEvent->scheduled()); 1612307SN/A transmitList.push_front(dp); 1622307SN/A } 1632292SN/A 1646221Snate@binkert.org waitingOnRetry = !success; 1652292SN/A 1662292SN/A if (waitingOnRetry) { 1672292SN/A DPRINTF(Bus, "Send failed, waiting on retry\n"); 1682292SN/A } 1692292SN/A} 1702292SN/A 1712292SN/A 1722292SN/Avoid 1732292SN/ASimpleTimingPort::recvRetry() 1742292SN/A{ 1752292SN/A DPRINTF(Bus, "Received retry\n"); 1762292SN/A assert(waitingOnRetry); 1772292SN/A sendDeferredPacket(); 1783867Sbinkertn@umich.edu} 1792292SN/A 1802292SN/A 1812292SN/Avoid 1822292SN/ASimpleTimingPort::processSendEvent() 1832292SN/A{ 1842292SN/A assert(!waitingOnRetry); 1852292SN/A sendDeferredPacket(); 1862292SN/A} 1872292SN/A 1882292SN/A 1892292SN/Aunsigned int 1906221Snate@binkert.orgSimpleTimingPort::drain(Event *de) 1916221Snate@binkert.org{ 1923867Sbinkertn@umich.edu if (transmitList.size() == 0) 1933867Sbinkertn@umich.edu return 0; 1946221Snate@binkert.org drainEvent = de; 1953867Sbinkertn@umich.edu return 1; 1963867Sbinkertn@umich.edu} 1972292SN/A