tport.hh revision 3349
12914Ssaidi@eecs.umich.edu/* 22914Ssaidi@eecs.umich.edu * Copyright (c) 2006 The Regents of The University of Michigan 32914Ssaidi@eecs.umich.edu * All rights reserved. 42914Ssaidi@eecs.umich.edu * 52914Ssaidi@eecs.umich.edu * Redistribution and use in source and binary forms, with or without 62914Ssaidi@eecs.umich.edu * modification, are permitted provided that the following conditions are 72914Ssaidi@eecs.umich.edu * met: redistributions of source code must retain the above copyright 82914Ssaidi@eecs.umich.edu * notice, this list of conditions and the following disclaimer; 92914Ssaidi@eecs.umich.edu * redistributions in binary form must reproduce the above copyright 102914Ssaidi@eecs.umich.edu * notice, this list of conditions and the following disclaimer in the 112914Ssaidi@eecs.umich.edu * documentation and/or other materials provided with the distribution; 122914Ssaidi@eecs.umich.edu * neither the name of the copyright holders nor the names of its 132914Ssaidi@eecs.umich.edu * contributors may be used to endorse or promote products derived from 142914Ssaidi@eecs.umich.edu * this software without specific prior written permission. 152914Ssaidi@eecs.umich.edu * 162914Ssaidi@eecs.umich.edu * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 172914Ssaidi@eecs.umich.edu * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 182914Ssaidi@eecs.umich.edu * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 192914Ssaidi@eecs.umich.edu * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 202914Ssaidi@eecs.umich.edu * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 212914Ssaidi@eecs.umich.edu * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 222914Ssaidi@eecs.umich.edu * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 232914Ssaidi@eecs.umich.edu * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 242914Ssaidi@eecs.umich.edu * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 252914Ssaidi@eecs.umich.edu * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 262914Ssaidi@eecs.umich.edu * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 272914Ssaidi@eecs.umich.edu * 282914Ssaidi@eecs.umich.edu * Authors: Ali Saidi 292914Ssaidi@eecs.umich.edu */ 302914Ssaidi@eecs.umich.edu 313091Sstever@eecs.umich.edu#ifndef __MEM_TPORT_HH__ 323091Sstever@eecs.umich.edu#define __MEM_TPORT_HH__ 333091Sstever@eecs.umich.edu 342914Ssaidi@eecs.umich.edu/** 352914Ssaidi@eecs.umich.edu * @file 363091Sstever@eecs.umich.edu * 373091Sstever@eecs.umich.edu * Declaration of SimpleTimingPort. 382914Ssaidi@eecs.umich.edu */ 392914Ssaidi@eecs.umich.edu 402914Ssaidi@eecs.umich.edu#include "mem/port.hh" 412914Ssaidi@eecs.umich.edu#include "sim/eventq.hh" 422914Ssaidi@eecs.umich.edu#include <list> 432914Ssaidi@eecs.umich.edu#include <string> 442914Ssaidi@eecs.umich.edu 453091Sstever@eecs.umich.edu/** 463091Sstever@eecs.umich.edu * A simple port for interfacing objects that basically have only 473091Sstever@eecs.umich.edu * functional memory behavior (e.g. I/O devices) to the memory system. 483091Sstever@eecs.umich.edu * Both timing and functional accesses are implemented in terms of 493091Sstever@eecs.umich.edu * atomic accesses. A derived port class thus only needs to provide 503091Sstever@eecs.umich.edu * recvAtomic() to support all memory access modes. 513091Sstever@eecs.umich.edu * 523091Sstever@eecs.umich.edu * The tricky part is handling recvTiming(), where the response must 533091Sstever@eecs.umich.edu * be scheduled separately via a later call to sendTiming(). This 543091Sstever@eecs.umich.edu * feature is handled by scheduling an internal event that calls 553091Sstever@eecs.umich.edu * sendTiming() after a delay, and optionally rescheduling the 563091Sstever@eecs.umich.edu * response if it is nacked. 573091Sstever@eecs.umich.edu */ 582914Ssaidi@eecs.umich.educlass SimpleTimingPort : public Port 592914Ssaidi@eecs.umich.edu{ 602914Ssaidi@eecs.umich.edu protected: 613090Sstever@eecs.umich.edu /** A list of outgoing timing response packets that haven't been 623090Sstever@eecs.umich.edu * serviced yet. */ 633349Sbinkertn@umich.edu std::list<PacketPtr> transmitList; 643091Sstever@eecs.umich.edu 652914Ssaidi@eecs.umich.edu /** 663090Sstever@eecs.umich.edu * This class is used to implemented sendTiming() with a delay. When 673090Sstever@eecs.umich.edu * a delay is requested a new event is created. When the event time 683090Sstever@eecs.umich.edu * expires it attempts to send the packet. If it cannot, the packet 693090Sstever@eecs.umich.edu * is pushed onto the transmit list to be sent when recvRetry() is 703090Sstever@eecs.umich.edu * called. */ 712914Ssaidi@eecs.umich.edu class SendEvent : public Event 722914Ssaidi@eecs.umich.edu { 732914Ssaidi@eecs.umich.edu SimpleTimingPort *port; 743349Sbinkertn@umich.edu PacketPtr packet; 752914Ssaidi@eecs.umich.edu 763090Sstever@eecs.umich.edu public: 773349Sbinkertn@umich.edu SendEvent(SimpleTimingPort *p, PacketPtr pkt, Tick t) 782914Ssaidi@eecs.umich.edu : Event(&mainEventQueue), port(p), packet(pkt) 792914Ssaidi@eecs.umich.edu { setFlags(AutoDelete); schedule(curTick + t); } 802914Ssaidi@eecs.umich.edu 812914Ssaidi@eecs.umich.edu virtual void process(); 822914Ssaidi@eecs.umich.edu 832914Ssaidi@eecs.umich.edu virtual const char *description() 842914Ssaidi@eecs.umich.edu { return "Future scheduled sendTiming event"; } 852914Ssaidi@eecs.umich.edu }; 862914Ssaidi@eecs.umich.edu 872914Ssaidi@eecs.umich.edu 882914Ssaidi@eecs.umich.edu /** Number of timing requests that are emulating the device timing before 892914Ssaidi@eecs.umich.edu * attempting to end up on the bus. 902914Ssaidi@eecs.umich.edu */ 912914Ssaidi@eecs.umich.edu int outTiming; 922914Ssaidi@eecs.umich.edu 932914Ssaidi@eecs.umich.edu /** If we need to drain, keep the drain event around until we're done 942914Ssaidi@eecs.umich.edu * here.*/ 952914Ssaidi@eecs.umich.edu Event *drainEvent; 962914Ssaidi@eecs.umich.edu 972914Ssaidi@eecs.umich.edu /** Schedule a sendTiming() event to be called in the future. */ 983349Sbinkertn@umich.edu void sendTimingLater(PacketPtr pkt, Tick time) 993091Sstever@eecs.umich.edu { outTiming++; new SendEvent(this, pkt, time); } 1002914Ssaidi@eecs.umich.edu 1012914Ssaidi@eecs.umich.edu /** This function is notification that the device should attempt to send a 1022914Ssaidi@eecs.umich.edu * packet again. */ 1032914Ssaidi@eecs.umich.edu virtual void recvRetry(); 1042914Ssaidi@eecs.umich.edu 1053091Sstever@eecs.umich.edu /** Implemented using recvAtomic(). */ 1063349Sbinkertn@umich.edu void recvFunctional(PacketPtr pkt); 1073091Sstever@eecs.umich.edu 1083091Sstever@eecs.umich.edu /** Implemented using recvAtomic(). */ 1093349Sbinkertn@umich.edu bool recvTiming(PacketPtr pkt); 1103091Sstever@eecs.umich.edu 1113091Sstever@eecs.umich.edu /** 1123091Sstever@eecs.umich.edu * Simple ports generally don't care about any status 1133091Sstever@eecs.umich.edu * changes... can always override this in cases where that's not 1143091Sstever@eecs.umich.edu * true. */ 1153091Sstever@eecs.umich.edu virtual void recvStatusChange(Status status) { } 1163091Sstever@eecs.umich.edu 1173091Sstever@eecs.umich.edu 1182914Ssaidi@eecs.umich.edu public: 1192914Ssaidi@eecs.umich.edu 1202914Ssaidi@eecs.umich.edu SimpleTimingPort(std::string pname) 1212914Ssaidi@eecs.umich.edu : Port(pname), outTiming(0), drainEvent(NULL) 1222914Ssaidi@eecs.umich.edu {} 1232914Ssaidi@eecs.umich.edu 1243091Sstever@eecs.umich.edu /** Hook for draining timing accesses from the system. The 1253091Sstever@eecs.umich.edu * associated SimObject's drain() functions should be implemented 1263091Sstever@eecs.umich.edu * something like this when this class is used: 1273091Sstever@eecs.umich.edu \code 1283091Sstever@eecs.umich.edu PioDevice::drain(Event *de) 1293091Sstever@eecs.umich.edu { 1303091Sstever@eecs.umich.edu unsigned int count; 1313091Sstever@eecs.umich.edu count = SimpleTimingPort->drain(de); 1323091Sstever@eecs.umich.edu if (count) 1333091Sstever@eecs.umich.edu changeState(Draining); 1343091Sstever@eecs.umich.edu else 1353091Sstever@eecs.umich.edu changeState(Drained); 1363091Sstever@eecs.umich.edu return count; 1373091Sstever@eecs.umich.edu } 1383091Sstever@eecs.umich.edu \endcode 1393091Sstever@eecs.umich.edu */ 1402914Ssaidi@eecs.umich.edu unsigned int drain(Event *de); 1412914Ssaidi@eecs.umich.edu}; 1422914Ssaidi@eecs.umich.edu 1432914Ssaidi@eecs.umich.edu#endif // __MEM_TPORT_HH__ 144