lsq_unit_impl.hh revision 2698
12292SN/A/*
22292SN/A * Copyright (c) 2004-2005 The Regents of The University of Michigan
32292SN/A * All rights reserved.
42292SN/A *
52292SN/A * Redistribution and use in source and binary forms, with or without
62292SN/A * modification, are permitted provided that the following conditions are
72292SN/A * met: redistributions of source code must retain the above copyright
82292SN/A * notice, this list of conditions and the following disclaimer;
92292SN/A * redistributions in binary form must reproduce the above copyright
102292SN/A * notice, this list of conditions and the following disclaimer in the
112292SN/A * documentation and/or other materials provided with the distribution;
122292SN/A * neither the name of the copyright holders nor the names of its
132292SN/A * contributors may be used to endorse or promote products derived from
142292SN/A * 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.
272689Sktlim@umich.edu *
282689Sktlim@umich.edu * Authors: Kevin Lim
292689Sktlim@umich.edu *          Korey Sewell
302292SN/A */
312292SN/A
322316SN/A#include "cpu/checker/cpu.hh"
332292SN/A#include "cpu/o3/lsq_unit.hh"
342292SN/A#include "base/str.hh"
352669Sktlim@umich.edu#include "mem/request.hh"
362292SN/A
372669Sktlim@umich.edutemplate<class Impl>
382678Sktlim@umich.eduLSQUnit<Impl>::WritebackEvent::WritebackEvent(DynInstPtr &_inst, PacketPtr _pkt,
392678Sktlim@umich.edu                                              LSQUnit *lsq_ptr)
402678Sktlim@umich.edu    : Event(&mainEventQueue), inst(_inst), pkt(_pkt), lsqPtr(lsq_ptr)
412292SN/A{
422678Sktlim@umich.edu    this->setFlags(Event::AutoDelete);
432292SN/A}
442292SN/A
452669Sktlim@umich.edutemplate<class Impl>
462292SN/Avoid
472678Sktlim@umich.eduLSQUnit<Impl>::WritebackEvent::process()
482292SN/A{
492678Sktlim@umich.edu    if (!lsqPtr->isSwitchedOut()) {
502678Sktlim@umich.edu        lsqPtr->writeback(inst, pkt);
512678Sktlim@umich.edu    }
522678Sktlim@umich.edu    delete pkt;
532678Sktlim@umich.edu}
542292SN/A
552678Sktlim@umich.edutemplate<class Impl>
562678Sktlim@umich.educonst char *
572678Sktlim@umich.eduLSQUnit<Impl>::WritebackEvent::description()
582678Sktlim@umich.edu{
592678Sktlim@umich.edu    return "Store writeback event";
602678Sktlim@umich.edu}
612292SN/A
622678Sktlim@umich.edutemplate<class Impl>
632678Sktlim@umich.eduvoid
642678Sktlim@umich.eduLSQUnit<Impl>::completeDataAccess(PacketPtr pkt)
652678Sktlim@umich.edu{
662678Sktlim@umich.edu    LSQSenderState *state = dynamic_cast<LSQSenderState *>(pkt->senderState);
672678Sktlim@umich.edu    DynInstPtr inst = state->inst;
682678Sktlim@umich.edu    DPRINTF(IEW, "Writeback event [sn:%lli]\n", inst->seqNum);
692698Sktlim@umich.edu    DPRINTF(Activity, "Activity: Writeback event [sn:%lli]\n", inst->seqNum);
702344SN/A
712678Sktlim@umich.edu    //iewStage->ldstQueue.removeMSHR(inst->threadNumber,inst->seqNum);
722678Sktlim@umich.edu
732678Sktlim@umich.edu    if (isSwitchedOut() || inst->isSquashed()) {
742678Sktlim@umich.edu        delete state;
752678Sktlim@umich.edu        delete pkt;
762307SN/A        return;
772678Sktlim@umich.edu    } else {
782678Sktlim@umich.edu        if (!state->noWB) {
792678Sktlim@umich.edu            writeback(inst, pkt);
802678Sktlim@umich.edu        }
812678Sktlim@umich.edu
822678Sktlim@umich.edu        if (inst->isStore()) {
832678Sktlim@umich.edu            completeStore(state->idx);
842678Sktlim@umich.edu        }
852344SN/A    }
862307SN/A
872678Sktlim@umich.edu    delete state;
882678Sktlim@umich.edu    delete pkt;
892292SN/A}
902292SN/A
912292SN/Atemplate <class Impl>
922669Sktlim@umich.eduTick
932669Sktlim@umich.eduLSQUnit<Impl>::DcachePort::recvAtomic(PacketPtr pkt)
942292SN/A{
952669Sktlim@umich.edu    panic("O3CPU model does not work with atomic mode!");
962669Sktlim@umich.edu    return curTick;
972669Sktlim@umich.edu}
982669Sktlim@umich.edu
992669Sktlim@umich.edutemplate <class Impl>
1002669Sktlim@umich.eduvoid
1012669Sktlim@umich.eduLSQUnit<Impl>::DcachePort::recvFunctional(PacketPtr pkt)
1022669Sktlim@umich.edu{
1032669Sktlim@umich.edu    panic("O3CPU doesn't expect recvFunctional callback!");
1042669Sktlim@umich.edu}
1052669Sktlim@umich.edu
1062669Sktlim@umich.edutemplate <class Impl>
1072669Sktlim@umich.eduvoid
1082669Sktlim@umich.eduLSQUnit<Impl>::DcachePort::recvStatusChange(Status status)
1092669Sktlim@umich.edu{
1102669Sktlim@umich.edu    if (status == RangeChange)
1112669Sktlim@umich.edu        return;
1122669Sktlim@umich.edu
1132669Sktlim@umich.edu    panic("O3CPU doesn't expect recvStatusChange callback!");
1142669Sktlim@umich.edu}
1152669Sktlim@umich.edu
1162669Sktlim@umich.edutemplate <class Impl>
1172669Sktlim@umich.edubool
1182669Sktlim@umich.eduLSQUnit<Impl>::DcachePort::recvTiming(PacketPtr pkt)
1192669Sktlim@umich.edu{
1202669Sktlim@umich.edu    lsq->completeDataAccess(pkt);
1212669Sktlim@umich.edu    return true;
1222669Sktlim@umich.edu}
1232669Sktlim@umich.edu
1242669Sktlim@umich.edutemplate <class Impl>
1252669Sktlim@umich.eduvoid
1262669Sktlim@umich.eduLSQUnit<Impl>::DcachePort::recvRetry()
1272669Sktlim@umich.edu{
1282693Sktlim@umich.edu    lsq->recvRetry();
1292292SN/A}
1302292SN/A
1312292SN/Atemplate <class Impl>
1322292SN/ALSQUnit<Impl>::LSQUnit()
1332678Sktlim@umich.edu    : loads(0), stores(0), storesToWB(0), stalled(false),
1342678Sktlim@umich.edu      isStoreBlocked(false), isLoadBlocked(false),
1352292SN/A      loadBlockedHandled(false)
1362292SN/A{
1372292SN/A}
1382292SN/A
1392292SN/Atemplate<class Impl>
1402292SN/Avoid
1412292SN/ALSQUnit<Impl>::init(Params *params, unsigned maxLQEntries,
1422292SN/A                    unsigned maxSQEntries, unsigned id)
1432292SN/A{
1442292SN/A    DPRINTF(LSQUnit, "Creating LSQUnit%i object.\n",id);
1452292SN/A
1462307SN/A    switchedOut = false;
1472307SN/A
1482292SN/A    lsqID = id;
1492292SN/A
1502329SN/A    // Add 1 for the sentinel entry (they are circular queues).
1512329SN/A    LQEntries = maxLQEntries + 1;
1522329SN/A    SQEntries = maxSQEntries + 1;
1532292SN/A
1542292SN/A    loadQueue.resize(LQEntries);
1552292SN/A    storeQueue.resize(SQEntries);
1562292SN/A
1572292SN/A    loadHead = loadTail = 0;
1582292SN/A
1592292SN/A    storeHead = storeWBIdx = storeTail = 0;
1602292SN/A
1612292SN/A    usedPorts = 0;
1622292SN/A    cachePorts = params->cachePorts;
1632292SN/A
1642678Sktlim@umich.edu    mem = params->mem;
1652292SN/A
1662329SN/A    memDepViolator = NULL;
1672292SN/A
1682292SN/A    blockedLoadSeqNum = 0;
1692292SN/A}
1702292SN/A
1712292SN/Atemplate<class Impl>
1722669Sktlim@umich.eduvoid
1732669Sktlim@umich.eduLSQUnit<Impl>::setCPU(FullCPU *cpu_ptr)
1742669Sktlim@umich.edu{
1752669Sktlim@umich.edu    cpu = cpu_ptr;
1762669Sktlim@umich.edu    dcachePort = new DcachePort(cpu, this);
1772678Sktlim@umich.edu
1782678Sktlim@umich.edu    Port *mem_dport = mem->getPort("");
1792678Sktlim@umich.edu    dcachePort->setPeer(mem_dport);
1802678Sktlim@umich.edu    mem_dport->setPeer(dcachePort);
1812679Sktlim@umich.edu
1822679Sktlim@umich.edu    if (cpu->checker) {
1832679Sktlim@umich.edu        cpu->checker->setDcachePort(dcachePort);
1842679Sktlim@umich.edu    }
1852669Sktlim@umich.edu}
1862669Sktlim@umich.edu
1872669Sktlim@umich.edutemplate<class Impl>
1882292SN/Astd::string
1892292SN/ALSQUnit<Impl>::name() const
1902292SN/A{
1912292SN/A    if (Impl::MaxThreads == 1) {
1922292SN/A        return iewStage->name() + ".lsq";
1932292SN/A    } else {
1942292SN/A        return iewStage->name() + ".lsq.thread." + to_string(lsqID);
1952292SN/A    }
1962292SN/A}
1972292SN/A
1982292SN/Atemplate<class Impl>
1992292SN/Avoid
2002292SN/ALSQUnit<Impl>::clearLQ()
2012292SN/A{
2022292SN/A    loadQueue.clear();
2032292SN/A}
2042292SN/A
2052292SN/Atemplate<class Impl>
2062292SN/Avoid
2072292SN/ALSQUnit<Impl>::clearSQ()
2082292SN/A{
2092292SN/A    storeQueue.clear();
2102292SN/A}
2112292SN/A
2122292SN/Atemplate<class Impl>
2132292SN/Avoid
2142307SN/ALSQUnit<Impl>::switchOut()
2152307SN/A{
2162307SN/A    switchedOut = true;
2172307SN/A    for (int i = 0; i < loadQueue.size(); ++i)
2182307SN/A        loadQueue[i] = NULL;
2192307SN/A
2202329SN/A    assert(storesToWB == 0);
2212307SN/A}
2222307SN/A
2232307SN/Atemplate<class Impl>
2242307SN/Avoid
2252307SN/ALSQUnit<Impl>::takeOverFrom()
2262307SN/A{
2272307SN/A    switchedOut = false;
2282307SN/A    loads = stores = storesToWB = 0;
2292307SN/A
2302307SN/A    loadHead = loadTail = 0;
2312307SN/A
2322307SN/A    storeHead = storeWBIdx = storeTail = 0;
2332307SN/A
2342307SN/A    usedPorts = 0;
2352307SN/A
2362329SN/A    memDepViolator = NULL;
2372307SN/A
2382307SN/A    blockedLoadSeqNum = 0;
2392307SN/A
2402307SN/A    stalled = false;
2412307SN/A    isLoadBlocked = false;
2422307SN/A    loadBlockedHandled = false;
2432307SN/A}
2442307SN/A
2452307SN/Atemplate<class Impl>
2462307SN/Avoid
2472292SN/ALSQUnit<Impl>::resizeLQ(unsigned size)
2482292SN/A{
2492329SN/A    unsigned size_plus_sentinel = size + 1;
2502329SN/A    assert(size_plus_sentinel >= LQEntries);
2512292SN/A
2522329SN/A    if (size_plus_sentinel > LQEntries) {
2532329SN/A        while (size_plus_sentinel > loadQueue.size()) {
2542292SN/A            DynInstPtr dummy;
2552292SN/A            loadQueue.push_back(dummy);
2562292SN/A            LQEntries++;
2572292SN/A        }
2582292SN/A    } else {
2592329SN/A        LQEntries = size_plus_sentinel;
2602292SN/A    }
2612292SN/A
2622292SN/A}
2632292SN/A
2642292SN/Atemplate<class Impl>
2652292SN/Avoid
2662292SN/ALSQUnit<Impl>::resizeSQ(unsigned size)
2672292SN/A{
2682329SN/A    unsigned size_plus_sentinel = size + 1;
2692329SN/A    if (size_plus_sentinel > SQEntries) {
2702329SN/A        while (size_plus_sentinel > storeQueue.size()) {
2712292SN/A            SQEntry dummy;
2722292SN/A            storeQueue.push_back(dummy);
2732292SN/A            SQEntries++;
2742292SN/A        }
2752292SN/A    } else {
2762329SN/A        SQEntries = size_plus_sentinel;
2772292SN/A    }
2782292SN/A}
2792292SN/A
2802292SN/Atemplate <class Impl>
2812292SN/Avoid
2822292SN/ALSQUnit<Impl>::insert(DynInstPtr &inst)
2832292SN/A{
2842292SN/A    assert(inst->isMemRef());
2852292SN/A
2862292SN/A    assert(inst->isLoad() || inst->isStore());
2872292SN/A
2882292SN/A    if (inst->isLoad()) {
2892292SN/A        insertLoad(inst);
2902292SN/A    } else {
2912292SN/A        insertStore(inst);
2922292SN/A    }
2932292SN/A
2942292SN/A    inst->setInLSQ();
2952292SN/A}
2962292SN/A
2972292SN/Atemplate <class Impl>
2982292SN/Avoid
2992292SN/ALSQUnit<Impl>::insertLoad(DynInstPtr &load_inst)
3002292SN/A{
3012329SN/A    assert((loadTail + 1) % LQEntries != loadHead);
3022329SN/A    assert(loads < LQEntries);
3032292SN/A
3042292SN/A    DPRINTF(LSQUnit, "Inserting load PC %#x, idx:%i [sn:%lli]\n",
3052292SN/A            load_inst->readPC(), loadTail, load_inst->seqNum);
3062292SN/A
3072292SN/A    load_inst->lqIdx = loadTail;
3082292SN/A
3092292SN/A    if (stores == 0) {
3102292SN/A        load_inst->sqIdx = -1;
3112292SN/A    } else {
3122292SN/A        load_inst->sqIdx = storeTail;
3132292SN/A    }
3142292SN/A
3152292SN/A    loadQueue[loadTail] = load_inst;
3162292SN/A
3172292SN/A    incrLdIdx(loadTail);
3182292SN/A
3192292SN/A    ++loads;
3202292SN/A}
3212292SN/A
3222292SN/Atemplate <class Impl>
3232292SN/Avoid
3242292SN/ALSQUnit<Impl>::insertStore(DynInstPtr &store_inst)
3252292SN/A{
3262292SN/A    // Make sure it is not full before inserting an instruction.
3272292SN/A    assert((storeTail + 1) % SQEntries != storeHead);
3282292SN/A    assert(stores < SQEntries);
3292292SN/A
3302292SN/A    DPRINTF(LSQUnit, "Inserting store PC %#x, idx:%i [sn:%lli]\n",
3312292SN/A            store_inst->readPC(), storeTail, store_inst->seqNum);
3322292SN/A
3332292SN/A    store_inst->sqIdx = storeTail;
3342292SN/A    store_inst->lqIdx = loadTail;
3352292SN/A
3362292SN/A    storeQueue[storeTail] = SQEntry(store_inst);
3372292SN/A
3382292SN/A    incrStIdx(storeTail);
3392292SN/A
3402292SN/A    ++stores;
3412292SN/A}
3422292SN/A
3432292SN/Atemplate <class Impl>
3442292SN/Atypename Impl::DynInstPtr
3452292SN/ALSQUnit<Impl>::getMemDepViolator()
3462292SN/A{
3472292SN/A    DynInstPtr temp = memDepViolator;
3482292SN/A
3492292SN/A    memDepViolator = NULL;
3502292SN/A
3512292SN/A    return temp;
3522292SN/A}
3532292SN/A
3542292SN/Atemplate <class Impl>
3552292SN/Aunsigned
3562292SN/ALSQUnit<Impl>::numFreeEntries()
3572292SN/A{
3582292SN/A    unsigned free_lq_entries = LQEntries - loads;
3592292SN/A    unsigned free_sq_entries = SQEntries - stores;
3602292SN/A
3612292SN/A    // Both the LQ and SQ entries have an extra dummy entry to differentiate
3622292SN/A    // empty/full conditions.  Subtract 1 from the free entries.
3632292SN/A    if (free_lq_entries < free_sq_entries) {
3642292SN/A        return free_lq_entries - 1;
3652292SN/A    } else {
3662292SN/A        return free_sq_entries - 1;
3672292SN/A    }
3682292SN/A}
3692292SN/A
3702292SN/Atemplate <class Impl>
3712292SN/Aint
3722292SN/ALSQUnit<Impl>::numLoadsReady()
3732292SN/A{
3742292SN/A    int load_idx = loadHead;
3752292SN/A    int retval = 0;
3762292SN/A
3772292SN/A    while (load_idx != loadTail) {
3782292SN/A        assert(loadQueue[load_idx]);
3792292SN/A
3802292SN/A        if (loadQueue[load_idx]->readyToIssue()) {
3812292SN/A            ++retval;
3822292SN/A        }
3832292SN/A    }
3842292SN/A
3852292SN/A    return retval;
3862292SN/A}
3872292SN/A
3882292SN/Atemplate <class Impl>
3892292SN/AFault
3902292SN/ALSQUnit<Impl>::executeLoad(DynInstPtr &inst)
3912292SN/A{
3922292SN/A    // Execute a specific load.
3932292SN/A    Fault load_fault = NoFault;
3942292SN/A
3952292SN/A    DPRINTF(LSQUnit, "Executing load PC %#x, [sn:%lli]\n",
3962292SN/A            inst->readPC(),inst->seqNum);
3972292SN/A
3982669Sktlim@umich.edu    load_fault = inst->initiateAcc();
3992292SN/A
4002292SN/A    // If the instruction faulted, then we need to send it along to commit
4012292SN/A    // without the instruction completing.
4022292SN/A    if (load_fault != NoFault) {
4032329SN/A        // Send this instruction to commit, also make sure iew stage
4042329SN/A        // realizes there is activity.
4052292SN/A        iewStage->instToCommit(inst);
4062292SN/A        iewStage->activityThisCycle();
4072292SN/A    }
4082292SN/A
4092292SN/A    return load_fault;
4102292SN/A}
4112292SN/A
4122292SN/Atemplate <class Impl>
4132292SN/AFault
4142292SN/ALSQUnit<Impl>::executeStore(DynInstPtr &store_inst)
4152292SN/A{
4162292SN/A    using namespace TheISA;
4172292SN/A    // Make sure that a store exists.
4182292SN/A    assert(stores != 0);
4192292SN/A
4202292SN/A    int store_idx = store_inst->sqIdx;
4212292SN/A
4222292SN/A    DPRINTF(LSQUnit, "Executing store PC %#x [sn:%lli]\n",
4232292SN/A            store_inst->readPC(), store_inst->seqNum);
4242292SN/A
4252292SN/A    // Check the recently completed loads to see if any match this store's
4262292SN/A    // address.  If so, then we have a memory ordering violation.
4272292SN/A    int load_idx = store_inst->lqIdx;
4282292SN/A
4292292SN/A    Fault store_fault = store_inst->initiateAcc();
4302292SN/A
4312329SN/A    if (storeQueue[store_idx].size == 0) {
4322292SN/A        DPRINTF(LSQUnit,"Fault on Store PC %#x, [sn:%lli],Size = 0\n",
4332292SN/A                store_inst->readPC(),store_inst->seqNum);
4342292SN/A
4352292SN/A        return store_fault;
4362292SN/A    }
4372292SN/A
4382292SN/A    assert(store_fault == NoFault);
4392292SN/A
4402336SN/A    if (store_inst->isStoreConditional()) {
4412336SN/A        // Store conditionals need to set themselves as able to
4422336SN/A        // writeback if we haven't had a fault by here.
4432329SN/A        storeQueue[store_idx].canWB = true;
4442292SN/A
4452329SN/A        ++storesToWB;
4462292SN/A    }
4472292SN/A
4482292SN/A    if (!memDepViolator) {
4492292SN/A        while (load_idx != loadTail) {
4502329SN/A            // Really only need to check loads that have actually executed
4512329SN/A            // It's safe to check all loads because effAddr is set to
4522329SN/A            // InvalAddr when the dyn inst is created.
4532292SN/A
4542329SN/A            // @todo: For now this is extra conservative, detecting a
4552329SN/A            // violation if the addresses match assuming all accesses
4562329SN/A            // are quad word accesses.
4572329SN/A
4582292SN/A            // @todo: Fix this, magic number being used here
4592292SN/A            if ((loadQueue[load_idx]->effAddr >> 8) ==
4602292SN/A                (store_inst->effAddr >> 8)) {
4612292SN/A                // A load incorrectly passed this store.  Squash and refetch.
4622292SN/A                // For now return a fault to show that it was unsuccessful.
4632292SN/A                memDepViolator = loadQueue[load_idx];
4642292SN/A
4652292SN/A                return genMachineCheckFault();
4662292SN/A            }
4672292SN/A
4682292SN/A            incrLdIdx(load_idx);
4692292SN/A        }
4702292SN/A
4712292SN/A        // If we've reached this point, there was no violation.
4722292SN/A        memDepViolator = NULL;
4732292SN/A    }
4742292SN/A
4752292SN/A    return store_fault;
4762292SN/A}
4772292SN/A
4782292SN/Atemplate <class Impl>
4792292SN/Avoid
4802292SN/ALSQUnit<Impl>::commitLoad()
4812292SN/A{
4822292SN/A    assert(loadQueue[loadHead]);
4832292SN/A
4842292SN/A    DPRINTF(LSQUnit, "Committing head load instruction, PC %#x\n",
4852292SN/A            loadQueue[loadHead]->readPC());
4862292SN/A
4872292SN/A    loadQueue[loadHead] = NULL;
4882292SN/A
4892292SN/A    incrLdIdx(loadHead);
4902292SN/A
4912292SN/A    --loads;
4922292SN/A}
4932292SN/A
4942292SN/Atemplate <class Impl>
4952292SN/Avoid
4962292SN/ALSQUnit<Impl>::commitLoads(InstSeqNum &youngest_inst)
4972292SN/A{
4982292SN/A    assert(loads == 0 || loadQueue[loadHead]);
4992292SN/A
5002292SN/A    while (loads != 0 && loadQueue[loadHead]->seqNum <= youngest_inst) {
5012292SN/A        commitLoad();
5022292SN/A    }
5032292SN/A}
5042292SN/A
5052292SN/Atemplate <class Impl>
5062292SN/Avoid
5072292SN/ALSQUnit<Impl>::commitStores(InstSeqNum &youngest_inst)
5082292SN/A{
5092292SN/A    assert(stores == 0 || storeQueue[storeHead].inst);
5102292SN/A
5112292SN/A    int store_idx = storeHead;
5122292SN/A
5132292SN/A    while (store_idx != storeTail) {
5142292SN/A        assert(storeQueue[store_idx].inst);
5152329SN/A        // Mark any stores that are now committed and have not yet
5162329SN/A        // been marked as able to write back.
5172292SN/A        if (!storeQueue[store_idx].canWB) {
5182292SN/A            if (storeQueue[store_idx].inst->seqNum > youngest_inst) {
5192292SN/A                break;
5202292SN/A            }
5212292SN/A            DPRINTF(LSQUnit, "Marking store as able to write back, PC "
5222292SN/A                    "%#x [sn:%lli]\n",
5232292SN/A                    storeQueue[store_idx].inst->readPC(),
5242292SN/A                    storeQueue[store_idx].inst->seqNum);
5252292SN/A
5262292SN/A            storeQueue[store_idx].canWB = true;
5272292SN/A
5282292SN/A            ++storesToWB;
5292292SN/A        }
5302292SN/A
5312292SN/A        incrStIdx(store_idx);
5322292SN/A    }
5332292SN/A}
5342292SN/A
5352292SN/Atemplate <class Impl>
5362292SN/Avoid
5372292SN/ALSQUnit<Impl>::writebackStores()
5382292SN/A{
5392292SN/A    while (storesToWB > 0 &&
5402292SN/A           storeWBIdx != storeTail &&
5412292SN/A           storeQueue[storeWBIdx].inst &&
5422292SN/A           storeQueue[storeWBIdx].canWB &&
5432292SN/A           usedPorts < cachePorts) {
5442292SN/A
5452678Sktlim@umich.edu        if (isStoreBlocked) {
5462678Sktlim@umich.edu            DPRINTF(LSQUnit, "Unable to write back any more stores, cache"
5472678Sktlim@umich.edu                    " is blocked!\n");
5482678Sktlim@umich.edu            break;
5492678Sktlim@umich.edu        }
5502678Sktlim@umich.edu
5512329SN/A        // Store didn't write any data so no need to write it back to
5522329SN/A        // memory.
5532292SN/A        if (storeQueue[storeWBIdx].size == 0) {
5542292SN/A            completeStore(storeWBIdx);
5552292SN/A
5562292SN/A            incrStIdx(storeWBIdx);
5572292SN/A
5582292SN/A            continue;
5592292SN/A        }
5602678Sktlim@umich.edu
5612292SN/A        ++usedPorts;
5622292SN/A
5632292SN/A        if (storeQueue[storeWBIdx].inst->isDataPrefetch()) {
5642292SN/A            incrStIdx(storeWBIdx);
5652292SN/A
5662292SN/A            continue;
5672292SN/A        }
5682292SN/A
5692292SN/A        assert(storeQueue[storeWBIdx].req);
5702292SN/A        assert(!storeQueue[storeWBIdx].committed);
5712292SN/A
5722669Sktlim@umich.edu        DynInstPtr inst = storeQueue[storeWBIdx].inst;
5732669Sktlim@umich.edu
5742669Sktlim@umich.edu        Request *req = storeQueue[storeWBIdx].req;
5752292SN/A        storeQueue[storeWBIdx].committed = true;
5762292SN/A
5772669Sktlim@umich.edu        assert(!inst->memData);
5782669Sktlim@umich.edu        inst->memData = new uint8_t[64];
5792678Sktlim@umich.edu        memcpy(inst->memData, (uint8_t *)&storeQueue[storeWBIdx].data,
5802678Sktlim@umich.edu               req->getSize());
5812669Sktlim@umich.edu
5822669Sktlim@umich.edu        PacketPtr data_pkt = new Packet(req, Packet::WriteReq, Packet::Broadcast);
5832669Sktlim@umich.edu        data_pkt->dataStatic(inst->memData);
5842292SN/A
5852678Sktlim@umich.edu        LSQSenderState *state = new LSQSenderState;
5862678Sktlim@umich.edu        state->isLoad = false;
5872678Sktlim@umich.edu        state->idx = storeWBIdx;
5882678Sktlim@umich.edu        state->inst = inst;
5892678Sktlim@umich.edu        data_pkt->senderState = state;
5902678Sktlim@umich.edu
5912292SN/A        DPRINTF(LSQUnit, "D-Cache: Writing back store idx:%i PC:%#x "
5922292SN/A                "to Addr:%#x, data:%#x [sn:%lli]\n",
5932669Sktlim@umich.edu                storeWBIdx, storeQueue[storeWBIdx].inst->readPC(),
5942669Sktlim@umich.edu                req->getPaddr(), *(inst->memData),
5952292SN/A                storeQueue[storeWBIdx].inst->seqNum);
5962292SN/A
5972693Sktlim@umich.edu        // @todo: Remove this SC hack once the memory system handles it.
5982693Sktlim@umich.edu        if (req->getFlags() & LOCKED) {
5992693Sktlim@umich.edu            if (req->getFlags() & UNCACHEABLE) {
6002693Sktlim@umich.edu                req->setScResult(2);
6012693Sktlim@umich.edu            } else {
6022693Sktlim@umich.edu                if (cpu->lockFlag) {
6032693Sktlim@umich.edu                    req->setScResult(1);
6042693Sktlim@umich.edu                } else {
6052693Sktlim@umich.edu                    req->setScResult(0);
6062693Sktlim@umich.edu                    // Hack: Instantly complete this store.
6072693Sktlim@umich.edu                    completeDataAccess(data_pkt);
6082693Sktlim@umich.edu                    incrStIdx(storeWBIdx);
6092693Sktlim@umich.edu                    continue;
6102693Sktlim@umich.edu                }
6112693Sktlim@umich.edu            }
6122693Sktlim@umich.edu        } else {
6132693Sktlim@umich.edu            // Non-store conditionals do not need a writeback.
6142693Sktlim@umich.edu            state->noWB = true;
6152693Sktlim@umich.edu        }
6162693Sktlim@umich.edu
6172669Sktlim@umich.edu        if (!dcachePort->sendTiming(data_pkt)) {
6182669Sktlim@umich.edu            // Need to handle becoming blocked on a store.
6192678Sktlim@umich.edu            isStoreBlocked = true;
6202693Sktlim@umich.edu
6212698Sktlim@umich.edu            assert(retryPkt == NULL);
6222698Sktlim@umich.edu            retryPkt = data_pkt;
6232669Sktlim@umich.edu        } else {
6242693Sktlim@umich.edu            storePostSend(data_pkt);
6252292SN/A        }
6262292SN/A    }
6272292SN/A
6282292SN/A    // Not sure this should set it to 0.
6292292SN/A    usedPorts = 0;
6302292SN/A
6312292SN/A    assert(stores >= 0 && storesToWB >= 0);
6322292SN/A}
6332292SN/A
6342292SN/A/*template <class Impl>
6352292SN/Avoid
6362292SN/ALSQUnit<Impl>::removeMSHR(InstSeqNum seqNum)
6372292SN/A{
6382292SN/A    list<InstSeqNum>::iterator mshr_it = find(mshrSeqNums.begin(),
6392292SN/A                                              mshrSeqNums.end(),
6402292SN/A                                              seqNum);
6412292SN/A
6422292SN/A    if (mshr_it != mshrSeqNums.end()) {
6432292SN/A        mshrSeqNums.erase(mshr_it);
6442292SN/A        DPRINTF(LSQUnit, "Removing MSHR. count = %i\n",mshrSeqNums.size());
6452292SN/A    }
6462292SN/A}*/
6472292SN/A
6482292SN/Atemplate <class Impl>
6492292SN/Avoid
6502292SN/ALSQUnit<Impl>::squash(const InstSeqNum &squashed_num)
6512292SN/A{
6522292SN/A    DPRINTF(LSQUnit, "Squashing until [sn:%lli]!"
6532329SN/A            "(Loads:%i Stores:%i)\n", squashed_num, loads, stores);
6542292SN/A
6552292SN/A    int load_idx = loadTail;
6562292SN/A    decrLdIdx(load_idx);
6572292SN/A
6582292SN/A    while (loads != 0 && loadQueue[load_idx]->seqNum > squashed_num) {
6592292SN/A        DPRINTF(LSQUnit,"Load Instruction PC %#x squashed, "
6602292SN/A                "[sn:%lli]\n",
6612292SN/A                loadQueue[load_idx]->readPC(),
6622292SN/A                loadQueue[load_idx]->seqNum);
6632292SN/A
6642292SN/A        if (isStalled() && load_idx == stallingLoadIdx) {
6652292SN/A            stalled = false;
6662292SN/A            stallingStoreIsn = 0;
6672292SN/A            stallingLoadIdx = 0;
6682292SN/A        }
6692292SN/A
6702329SN/A        // Clear the smart pointer to make sure it is decremented.
6712292SN/A        loadQueue[load_idx]->squashed = true;
6722292SN/A        loadQueue[load_idx] = NULL;
6732292SN/A        --loads;
6742292SN/A
6752292SN/A        // Inefficient!
6762292SN/A        loadTail = load_idx;
6772292SN/A
6782292SN/A        decrLdIdx(load_idx);
6792292SN/A    }
6802292SN/A
6812292SN/A    if (isLoadBlocked) {
6822292SN/A        if (squashed_num < blockedLoadSeqNum) {
6832292SN/A            isLoadBlocked = false;
6842292SN/A            loadBlockedHandled = false;
6852292SN/A            blockedLoadSeqNum = 0;
6862292SN/A        }
6872292SN/A    }
6882292SN/A
6892292SN/A    int store_idx = storeTail;
6902292SN/A    decrStIdx(store_idx);
6912292SN/A
6922292SN/A    while (stores != 0 &&
6932292SN/A           storeQueue[store_idx].inst->seqNum > squashed_num) {
6942329SN/A        // Instructions marked as can WB are already committed.
6952292SN/A        if (storeQueue[store_idx].canWB) {
6962292SN/A            break;
6972292SN/A        }
6982292SN/A
6992292SN/A        DPRINTF(LSQUnit,"Store Instruction PC %#x squashed, "
7002292SN/A                "idx:%i [sn:%lli]\n",
7012292SN/A                storeQueue[store_idx].inst->readPC(),
7022292SN/A                store_idx, storeQueue[store_idx].inst->seqNum);
7032292SN/A
7042329SN/A        // I don't think this can happen.  It should have been cleared
7052329SN/A        // by the stalling load.
7062292SN/A        if (isStalled() &&
7072292SN/A            storeQueue[store_idx].inst->seqNum == stallingStoreIsn) {
7082292SN/A            panic("Is stalled should have been cleared by stalling load!\n");
7092292SN/A            stalled = false;
7102292SN/A            stallingStoreIsn = 0;
7112292SN/A        }
7122292SN/A
7132329SN/A        // Clear the smart pointer to make sure it is decremented.
7142292SN/A        storeQueue[store_idx].inst->squashed = true;
7152292SN/A        storeQueue[store_idx].inst = NULL;
7162292SN/A        storeQueue[store_idx].canWB = 0;
7172292SN/A
7182292SN/A        storeQueue[store_idx].req = NULL;
7192292SN/A        --stores;
7202292SN/A
7212292SN/A        // Inefficient!
7222292SN/A        storeTail = store_idx;
7232292SN/A
7242292SN/A        decrStIdx(store_idx);
7252292SN/A    }
7262292SN/A}
7272292SN/A
7282292SN/Atemplate <class Impl>
7292292SN/Avoid
7302693Sktlim@umich.eduLSQUnit<Impl>::storePostSend(Packet *pkt)
7312693Sktlim@umich.edu{
7322693Sktlim@umich.edu    if (isStalled() &&
7332693Sktlim@umich.edu        storeQueue[storeWBIdx].inst->seqNum == stallingStoreIsn) {
7342693Sktlim@umich.edu        DPRINTF(LSQUnit, "Unstalling, stalling store [sn:%lli] "
7352693Sktlim@umich.edu                "load idx:%i\n",
7362693Sktlim@umich.edu                stallingStoreIsn, stallingLoadIdx);
7372693Sktlim@umich.edu        stalled = false;
7382693Sktlim@umich.edu        stallingStoreIsn = 0;
7392693Sktlim@umich.edu        iewStage->replayMemInst(loadQueue[stallingLoadIdx]);
7402693Sktlim@umich.edu    }
7412693Sktlim@umich.edu
7422693Sktlim@umich.edu    if (!storeQueue[storeWBIdx].inst->isStoreConditional()) {
7432693Sktlim@umich.edu        // The store is basically completed at this time. This
7442693Sktlim@umich.edu        // only works so long as the checker doesn't try to
7452693Sktlim@umich.edu        // verify the value in memory for stores.
7462693Sktlim@umich.edu        storeQueue[storeWBIdx].inst->setCompleted();
7472693Sktlim@umich.edu        if (cpu->checker) {
7482693Sktlim@umich.edu            cpu->checker->tick(storeQueue[storeWBIdx].inst);
7492693Sktlim@umich.edu        }
7502693Sktlim@umich.edu    }
7512693Sktlim@umich.edu
7522693Sktlim@umich.edu    if (pkt->result != Packet::Success) {
7532693Sktlim@umich.edu        DPRINTF(LSQUnit,"D-Cache Write Miss on idx:%i!\n",
7542693Sktlim@umich.edu                storeWBIdx);
7552693Sktlim@umich.edu
7562693Sktlim@umich.edu        DPRINTF(Activity, "Active st accessing mem miss [sn:%lli]\n",
7572693Sktlim@umich.edu                storeQueue[storeWBIdx].inst->seqNum);
7582693Sktlim@umich.edu
7592693Sktlim@umich.edu        //mshrSeqNums.push_back(storeQueue[storeWBIdx].inst->seqNum);
7602693Sktlim@umich.edu
7612693Sktlim@umich.edu        //DPRINTF(LSQUnit, "Added MSHR. count = %i\n",mshrSeqNums.size());
7622693Sktlim@umich.edu
7632693Sktlim@umich.edu        // @todo: Increment stat here.
7642693Sktlim@umich.edu    } else {
7652693Sktlim@umich.edu        DPRINTF(LSQUnit,"D-Cache: Write Hit on idx:%i !\n",
7662693Sktlim@umich.edu                storeWBIdx);
7672693Sktlim@umich.edu
7682693Sktlim@umich.edu        DPRINTF(Activity, "Active st accessing mem hit [sn:%lli]\n",
7692693Sktlim@umich.edu                storeQueue[storeWBIdx].inst->seqNum);
7702693Sktlim@umich.edu    }
7712693Sktlim@umich.edu
7722693Sktlim@umich.edu    incrStIdx(storeWBIdx);
7732693Sktlim@umich.edu}
7742693Sktlim@umich.edu
7752693Sktlim@umich.edutemplate <class Impl>
7762693Sktlim@umich.eduvoid
7772678Sktlim@umich.eduLSQUnit<Impl>::writeback(DynInstPtr &inst, PacketPtr pkt)
7782678Sktlim@umich.edu{
7792678Sktlim@umich.edu    iewStage->wakeCPU();
7802678Sktlim@umich.edu
7812678Sktlim@umich.edu    // Squashed instructions do not need to complete their access.
7822678Sktlim@umich.edu    if (inst->isSquashed()) {
7832678Sktlim@umich.edu        assert(!inst->isStore());
7842678Sktlim@umich.edu        return;
7852678Sktlim@umich.edu    }
7862678Sktlim@umich.edu
7872678Sktlim@umich.edu    if (!inst->isExecuted()) {
7882678Sktlim@umich.edu        inst->setExecuted();
7892678Sktlim@umich.edu
7902678Sktlim@umich.edu        // Complete access to copy data to proper place.
7912678Sktlim@umich.edu        inst->completeAcc(pkt);
7922678Sktlim@umich.edu    }
7932678Sktlim@umich.edu
7942678Sktlim@umich.edu    // Need to insert instruction into queue to commit
7952678Sktlim@umich.edu    iewStage->instToCommit(inst);
7962678Sktlim@umich.edu
7972678Sktlim@umich.edu    iewStage->activityThisCycle();
7982678Sktlim@umich.edu}
7992678Sktlim@umich.edu
8002678Sktlim@umich.edutemplate <class Impl>
8012678Sktlim@umich.eduvoid
8022292SN/ALSQUnit<Impl>::completeStore(int store_idx)
8032292SN/A{
8042292SN/A    assert(storeQueue[store_idx].inst);
8052292SN/A    storeQueue[store_idx].completed = true;
8062292SN/A    --storesToWB;
8072292SN/A    // A bit conservative because a store completion may not free up entries,
8082292SN/A    // but hopefully avoids two store completions in one cycle from making
8092292SN/A    // the CPU tick twice.
8102292SN/A    cpu->activityThisCycle();
8112292SN/A
8122292SN/A    if (store_idx == storeHead) {
8132292SN/A        do {
8142292SN/A            incrStIdx(storeHead);
8152292SN/A
8162292SN/A            --stores;
8172292SN/A        } while (storeQueue[storeHead].completed &&
8182292SN/A                 storeHead != storeTail);
8192292SN/A
8202292SN/A        iewStage->updateLSQNextCycle = true;
8212292SN/A    }
8222292SN/A
8232329SN/A    DPRINTF(LSQUnit, "Completing store [sn:%lli], idx:%i, store head "
8242329SN/A            "idx:%i\n",
8252329SN/A            storeQueue[store_idx].inst->seqNum, store_idx, storeHead);
8262292SN/A
8272292SN/A    if (isStalled() &&
8282292SN/A        storeQueue[store_idx].inst->seqNum == stallingStoreIsn) {
8292292SN/A        DPRINTF(LSQUnit, "Unstalling, stalling store [sn:%lli] "
8302292SN/A                "load idx:%i\n",
8312292SN/A                stallingStoreIsn, stallingLoadIdx);
8322292SN/A        stalled = false;
8332292SN/A        stallingStoreIsn = 0;
8342292SN/A        iewStage->replayMemInst(loadQueue[stallingLoadIdx]);
8352292SN/A    }
8362316SN/A
8372316SN/A    storeQueue[store_idx].inst->setCompleted();
8382329SN/A
8392329SN/A    // Tell the checker we've completed this instruction.  Some stores
8402329SN/A    // may get reported twice to the checker, but the checker can
8412329SN/A    // handle that case.
8422316SN/A    if (cpu->checker) {
8432316SN/A        cpu->checker->tick(storeQueue[store_idx].inst);
8442316SN/A    }
8452292SN/A}
8462292SN/A
8472292SN/Atemplate <class Impl>
8482693Sktlim@umich.eduvoid
8492693Sktlim@umich.eduLSQUnit<Impl>::recvRetry()
8502693Sktlim@umich.edu{
8512698Sktlim@umich.edu    if (isStoreBlocked) {
8522698Sktlim@umich.edu        assert(retryPkt != NULL);
8532693Sktlim@umich.edu
8542698Sktlim@umich.edu        if (dcachePort->sendTiming(retryPkt)) {
8552698Sktlim@umich.edu            storePostSend(retryPkt);
8562693Sktlim@umich.edu            sendingPkt = NULL;
8572693Sktlim@umich.edu            isStoreBlocked = false;
8582693Sktlim@umich.edu        } else {
8592693Sktlim@umich.edu            // Still blocked!
8602693Sktlim@umich.edu        }
8612693Sktlim@umich.edu    } else if (isLoadBlocked) {
8622693Sktlim@umich.edu        DPRINTF(LSQUnit, "Loads squash themselves and all younger insts, "
8632693Sktlim@umich.edu                "no need to resend packet.\n");
8642693Sktlim@umich.edu    } else {
8652693Sktlim@umich.edu        DPRINTF(LSQUnit, "Retry received but LSQ is no longer blocked.\n");
8662693Sktlim@umich.edu    }
8672693Sktlim@umich.edu}
8682693Sktlim@umich.edu
8692693Sktlim@umich.edutemplate <class Impl>
8702292SN/Ainline void
8712292SN/ALSQUnit<Impl>::incrStIdx(int &store_idx)
8722292SN/A{
8732292SN/A    if (++store_idx >= SQEntries)
8742292SN/A        store_idx = 0;
8752292SN/A}
8762292SN/A
8772292SN/Atemplate <class Impl>
8782292SN/Ainline void
8792292SN/ALSQUnit<Impl>::decrStIdx(int &store_idx)
8802292SN/A{
8812292SN/A    if (--store_idx < 0)
8822292SN/A        store_idx += SQEntries;
8832292SN/A}
8842292SN/A
8852292SN/Atemplate <class Impl>
8862292SN/Ainline void
8872292SN/ALSQUnit<Impl>::incrLdIdx(int &load_idx)
8882292SN/A{
8892292SN/A    if (++load_idx >= LQEntries)
8902292SN/A        load_idx = 0;
8912292SN/A}
8922292SN/A
8932292SN/Atemplate <class Impl>
8942292SN/Ainline void
8952292SN/ALSQUnit<Impl>::decrLdIdx(int &load_idx)
8962292SN/A{
8972292SN/A    if (--load_idx < 0)
8982292SN/A        load_idx += LQEntries;
8992292SN/A}
9002329SN/A
9012329SN/Atemplate <class Impl>
9022329SN/Avoid
9032329SN/ALSQUnit<Impl>::dumpInsts()
9042329SN/A{
9052329SN/A    cprintf("Load store queue: Dumping instructions.\n");
9062329SN/A    cprintf("Load queue size: %i\n", loads);
9072329SN/A    cprintf("Load queue: ");
9082329SN/A
9092329SN/A    int load_idx = loadHead;
9102329SN/A
9112329SN/A    while (load_idx != loadTail && loadQueue[load_idx]) {
9122329SN/A        cprintf("%#x ", loadQueue[load_idx]->readPC());
9132329SN/A
9142329SN/A        incrLdIdx(load_idx);
9152329SN/A    }
9162329SN/A
9172329SN/A    cprintf("Store queue size: %i\n", stores);
9182329SN/A    cprintf("Store queue: ");
9192329SN/A
9202329SN/A    int store_idx = storeHead;
9212329SN/A
9222329SN/A    while (store_idx != storeTail && storeQueue[store_idx].inst) {
9232329SN/A        cprintf("%#x ", storeQueue[store_idx].inst->readPC());
9242329SN/A
9252329SN/A        incrStIdx(store_idx);
9262329SN/A    }
9272329SN/A
9282329SN/A    cprintf("\n");
9292329SN/A}
930