timing.cc revision 8949:3fa1ee293096
1/* 2 * Copyright (c) 2010-2012 ARM Limited 3 * All rights reserved 4 * 5 * The license below extends only to copyright in the software and shall 6 * not be construed as granting a license to any other intellectual 7 * property including but not limited to intellectual property relating 8 * to a hardware implementation of the functionality of the software 9 * licensed hereunder. You may use the software subject to the license 10 * terms below provided that you ensure that this notice is replicated 11 * unmodified and in its entirety in all distributions of the software, 12 * modified or unmodified, in source code or in binary form. 13 * 14 * Copyright (c) 2002-2005 The Regents of The University of Michigan 15 * All rights reserved. 16 * 17 * Redistribution and use in source and binary forms, with or without 18 * modification, are permitted provided that the following conditions are 19 * met: redistributions of source code must retain the above copyright 20 * notice, this list of conditions and the following disclaimer; 21 * redistributions in binary form must reproduce the above copyright 22 * notice, this list of conditions and the following disclaimer in the 23 * documentation and/or other materials provided with the distribution; 24 * neither the name of the copyright holders nor the names of its 25 * contributors may be used to endorse or promote products derived from 26 * this software without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 29 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 30 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 31 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 32 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 33 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 34 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 35 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 36 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 37 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 38 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 39 * 40 * Authors: Steve Reinhardt 41 */ 42 43#include "arch/locked_mem.hh" 44#include "arch/mmapped_ipr.hh" 45#include "arch/utility.hh" 46#include "base/bigint.hh" 47#include "config/the_isa.hh" 48#include "cpu/simple/timing.hh" 49#include "cpu/exetrace.hh" 50#include "debug/Config.hh" 51#include "debug/ExecFaulting.hh" 52#include "debug/SimpleCPU.hh" 53#include "mem/packet.hh" 54#include "mem/packet_access.hh" 55#include "params/TimingSimpleCPU.hh" 56#include "sim/faults.hh" 57#include "sim/full_system.hh" 58#include "sim/system.hh" 59 60using namespace std; 61using namespace TheISA; 62 63void 64TimingSimpleCPU::init() 65{ 66 BaseCPU::init(); 67 68 // Initialise the ThreadContext's memory proxies 69 tcBase()->initMemProxies(tcBase()); 70 71 if (FullSystem) { 72 for (int i = 0; i < threadContexts.size(); ++i) { 73 ThreadContext *tc = threadContexts[i]; 74 // initialize CPU, including PC 75 TheISA::initCPU(tc, _cpuId); 76 } 77 } 78} 79 80void 81TimingSimpleCPU::TimingCPUPort::TickEvent::schedule(PacketPtr _pkt, Tick t) 82{ 83 pkt = _pkt; 84 cpu->schedule(this, t); 85} 86 87TimingSimpleCPU::TimingSimpleCPU(TimingSimpleCPUParams *p) 88 : BaseSimpleCPU(p), fetchTranslation(this), icachePort(this), 89 dcachePort(this), fetchEvent(this) 90{ 91 _status = Idle; 92 93 ifetch_pkt = dcache_pkt = NULL; 94 drainEvent = NULL; 95 previousTick = 0; 96 changeState(SimObject::Running); 97 system->totalNumInsts = 0; 98} 99 100 101TimingSimpleCPU::~TimingSimpleCPU() 102{ 103} 104 105void 106TimingSimpleCPU::serialize(ostream &os) 107{ 108 SimObject::State so_state = SimObject::getState(); 109 SERIALIZE_ENUM(so_state); 110 BaseSimpleCPU::serialize(os); 111} 112 113void 114TimingSimpleCPU::unserialize(Checkpoint *cp, const string §ion) 115{ 116 SimObject::State so_state; 117 UNSERIALIZE_ENUM(so_state); 118 BaseSimpleCPU::unserialize(cp, section); 119} 120 121unsigned int 122TimingSimpleCPU::drain(Event *drain_event) 123{ 124 // TimingSimpleCPU is ready to drain if it's not waiting for 125 // an access to complete. 126 if (_status == Idle || _status == Running || _status == SwitchedOut) { 127 changeState(SimObject::Drained); 128 return 0; 129 } else { 130 changeState(SimObject::Draining); 131 drainEvent = drain_event; 132 return 1; 133 } 134} 135 136void 137TimingSimpleCPU::resume() 138{ 139 DPRINTF(SimpleCPU, "Resume\n"); 140 if (_status != SwitchedOut && _status != Idle) { 141 assert(system->getMemoryMode() == Enums::timing); 142 143 if (fetchEvent.scheduled()) 144 deschedule(fetchEvent); 145 146 schedule(fetchEvent, nextCycle()); 147 } 148 149 changeState(SimObject::Running); 150} 151 152void 153TimingSimpleCPU::switchOut() 154{ 155 assert(_status == Running || _status == Idle); 156 _status = SwitchedOut; 157 numCycles += tickToCycles(curTick() - previousTick); 158 159 // If we've been scheduled to resume but are then told to switch out, 160 // we'll need to cancel it. 161 if (fetchEvent.scheduled()) 162 deschedule(fetchEvent); 163} 164 165 166void 167TimingSimpleCPU::takeOverFrom(BaseCPU *oldCPU) 168{ 169 BaseCPU::takeOverFrom(oldCPU); 170 171 // if any of this CPU's ThreadContexts are active, mark the CPU as 172 // running and schedule its tick event. 173 for (int i = 0; i < threadContexts.size(); ++i) { 174 ThreadContext *tc = threadContexts[i]; 175 if (tc->status() == ThreadContext::Active && _status != Running) { 176 _status = Running; 177 break; 178 } 179 } 180 181 if (_status != Running) { 182 _status = Idle; 183 } 184 assert(threadContexts.size() == 1); 185 previousTick = curTick(); 186} 187 188 189void 190TimingSimpleCPU::activateContext(ThreadID thread_num, int delay) 191{ 192 DPRINTF(SimpleCPU, "ActivateContext %d (%d cycles)\n", thread_num, delay); 193 194 assert(thread_num == 0); 195 assert(thread); 196 197 assert(_status == Idle); 198 199 notIdleFraction++; 200 _status = Running; 201 202 // kick things off by initiating the fetch of the next instruction 203 schedule(fetchEvent, nextCycle(curTick() + ticks(delay))); 204} 205 206 207void 208TimingSimpleCPU::suspendContext(ThreadID thread_num) 209{ 210 DPRINTF(SimpleCPU, "SuspendContext %d\n", thread_num); 211 212 assert(thread_num == 0); 213 assert(thread); 214 215 if (_status == Idle) 216 return; 217 218 assert(_status == Running); 219 220 // just change status to Idle... if status != Running, 221 // completeInst() will not initiate fetch of next instruction. 222 223 notIdleFraction--; 224 _status = Idle; 225} 226 227bool 228TimingSimpleCPU::handleReadPacket(PacketPtr pkt) 229{ 230 RequestPtr req = pkt->req; 231 if (req->isMmappedIpr()) { 232 Tick delay; 233 delay = TheISA::handleIprRead(thread->getTC(), pkt); 234 new IprEvent(pkt, this, nextCycle(curTick() + delay)); 235 _status = DcacheWaitResponse; 236 dcache_pkt = NULL; 237 } else if (!dcachePort.sendTiming(pkt)) { 238 _status = DcacheRetry; 239 dcache_pkt = pkt; 240 } else { 241 _status = DcacheWaitResponse; 242 // memory system takes ownership of packet 243 dcache_pkt = NULL; 244 } 245 return dcache_pkt == NULL; 246} 247 248void 249TimingSimpleCPU::sendData(RequestPtr req, uint8_t *data, uint64_t *res, 250 bool read) 251{ 252 PacketPtr pkt; 253 buildPacket(pkt, req, read); 254 pkt->dataDynamicArray<uint8_t>(data); 255 if (req->getFlags().isSet(Request::NO_ACCESS)) { 256 assert(!dcache_pkt); 257 pkt->makeResponse(); 258 completeDataAccess(pkt); 259 } else if (read) { 260 handleReadPacket(pkt); 261 } else { 262 bool do_access = true; // flag to suppress cache access 263 264 if (req->isLLSC()) { 265 do_access = TheISA::handleLockedWrite(thread, req); 266 } else if (req->isCondSwap()) { 267 assert(res); 268 req->setExtraData(*res); 269 } 270 271 if (do_access) { 272 dcache_pkt = pkt; 273 handleWritePacket(); 274 } else { 275 _status = DcacheWaitResponse; 276 completeDataAccess(pkt); 277 } 278 } 279} 280 281void 282TimingSimpleCPU::sendSplitData(RequestPtr req1, RequestPtr req2, 283 RequestPtr req, uint8_t *data, bool read) 284{ 285 PacketPtr pkt1, pkt2; 286 buildSplitPacket(pkt1, pkt2, req1, req2, req, data, read); 287 if (req->getFlags().isSet(Request::NO_ACCESS)) { 288 assert(!dcache_pkt); 289 pkt1->makeResponse(); 290 completeDataAccess(pkt1); 291 } else if (read) { 292 SplitFragmentSenderState * send_state = 293 dynamic_cast<SplitFragmentSenderState *>(pkt1->senderState); 294 if (handleReadPacket(pkt1)) { 295 send_state->clearFromParent(); 296 send_state = dynamic_cast<SplitFragmentSenderState *>( 297 pkt2->senderState); 298 if (handleReadPacket(pkt2)) { 299 send_state->clearFromParent(); 300 } 301 } 302 } else { 303 dcache_pkt = pkt1; 304 SplitFragmentSenderState * send_state = 305 dynamic_cast<SplitFragmentSenderState *>(pkt1->senderState); 306 if (handleWritePacket()) { 307 send_state->clearFromParent(); 308 dcache_pkt = pkt2; 309 send_state = dynamic_cast<SplitFragmentSenderState *>( 310 pkt2->senderState); 311 if (handleWritePacket()) { 312 send_state->clearFromParent(); 313 } 314 } 315 } 316} 317 318void 319TimingSimpleCPU::translationFault(Fault fault) 320{ 321 // fault may be NoFault in cases where a fault is suppressed, 322 // for instance prefetches. 323 numCycles += tickToCycles(curTick() - previousTick); 324 previousTick = curTick(); 325 326 if (traceData) { 327 // Since there was a fault, we shouldn't trace this instruction. 328 delete traceData; 329 traceData = NULL; 330 } 331 332 postExecute(); 333 334 if (getState() == SimObject::Draining) { 335 advancePC(fault); 336 completeDrain(); 337 } else { 338 advanceInst(fault); 339 } 340} 341 342void 343TimingSimpleCPU::buildPacket(PacketPtr &pkt, RequestPtr req, bool read) 344{ 345 MemCmd cmd; 346 if (read) { 347 cmd = MemCmd::ReadReq; 348 if (req->isLLSC()) 349 cmd = MemCmd::LoadLockedReq; 350 } else { 351 cmd = MemCmd::WriteReq; 352 if (req->isLLSC()) { 353 cmd = MemCmd::StoreCondReq; 354 } else if (req->isSwap()) { 355 cmd = MemCmd::SwapReq; 356 } 357 } 358 pkt = new Packet(req, cmd); 359} 360 361void 362TimingSimpleCPU::buildSplitPacket(PacketPtr &pkt1, PacketPtr &pkt2, 363 RequestPtr req1, RequestPtr req2, RequestPtr req, 364 uint8_t *data, bool read) 365{ 366 pkt1 = pkt2 = NULL; 367 368 assert(!req1->isMmappedIpr() && !req2->isMmappedIpr()); 369 370 if (req->getFlags().isSet(Request::NO_ACCESS)) { 371 buildPacket(pkt1, req, read); 372 return; 373 } 374 375 buildPacket(pkt1, req1, read); 376 buildPacket(pkt2, req2, read); 377 378 req->setPhys(req1->getPaddr(), req->getSize(), req1->getFlags(), dataMasterId()); 379 PacketPtr pkt = new Packet(req, pkt1->cmd.responseCommand()); 380 381 pkt->dataDynamicArray<uint8_t>(data); 382 pkt1->dataStatic<uint8_t>(data); 383 pkt2->dataStatic<uint8_t>(data + req1->getSize()); 384 385 SplitMainSenderState * main_send_state = new SplitMainSenderState; 386 pkt->senderState = main_send_state; 387 main_send_state->fragments[0] = pkt1; 388 main_send_state->fragments[1] = pkt2; 389 main_send_state->outstanding = 2; 390 pkt1->senderState = new SplitFragmentSenderState(pkt, 0); 391 pkt2->senderState = new SplitFragmentSenderState(pkt, 1); 392} 393 394Fault 395TimingSimpleCPU::readMem(Addr addr, uint8_t *data, 396 unsigned size, unsigned flags) 397{ 398 Fault fault; 399 const int asid = 0; 400 const ThreadID tid = 0; 401 const Addr pc = thread->instAddr(); 402 unsigned block_size = dcachePort.peerBlockSize(); 403 BaseTLB::Mode mode = BaseTLB::Read; 404 405 if (traceData) { 406 traceData->setAddr(addr); 407 } 408 409 RequestPtr req = new Request(asid, addr, size, 410 flags, dataMasterId(), pc, _cpuId, tid); 411 412 Addr split_addr = roundDown(addr + size - 1, block_size); 413 assert(split_addr <= addr || split_addr - addr < block_size); 414 415 _status = DTBWaitResponse; 416 if (split_addr > addr) { 417 RequestPtr req1, req2; 418 assert(!req->isLLSC() && !req->isSwap()); 419 req->splitOnVaddr(split_addr, req1, req2); 420 421 WholeTranslationState *state = 422 new WholeTranslationState(req, req1, req2, new uint8_t[size], 423 NULL, mode); 424 DataTranslation<TimingSimpleCPU *> *trans1 = 425 new DataTranslation<TimingSimpleCPU *>(this, state, 0); 426 DataTranslation<TimingSimpleCPU *> *trans2 = 427 new DataTranslation<TimingSimpleCPU *>(this, state, 1); 428 429 thread->dtb->translateTiming(req1, tc, trans1, mode); 430 thread->dtb->translateTiming(req2, tc, trans2, mode); 431 } else { 432 WholeTranslationState *state = 433 new WholeTranslationState(req, new uint8_t[size], NULL, mode); 434 DataTranslation<TimingSimpleCPU *> *translation 435 = new DataTranslation<TimingSimpleCPU *>(this, state); 436 thread->dtb->translateTiming(req, tc, translation, mode); 437 } 438 439 return NoFault; 440} 441 442bool 443TimingSimpleCPU::handleWritePacket() 444{ 445 RequestPtr req = dcache_pkt->req; 446 if (req->isMmappedIpr()) { 447 Tick delay; 448 delay = TheISA::handleIprWrite(thread->getTC(), dcache_pkt); 449 new IprEvent(dcache_pkt, this, nextCycle(curTick() + delay)); 450 _status = DcacheWaitResponse; 451 dcache_pkt = NULL; 452 } else if (!dcachePort.sendTiming(dcache_pkt)) { 453 _status = DcacheRetry; 454 } else { 455 _status = DcacheWaitResponse; 456 // memory system takes ownership of packet 457 dcache_pkt = NULL; 458 } 459 return dcache_pkt == NULL; 460} 461 462Fault 463TimingSimpleCPU::writeMem(uint8_t *data, unsigned size, 464 Addr addr, unsigned flags, uint64_t *res) 465{ 466 uint8_t *newData = new uint8_t[size]; 467 memcpy(newData, data, size); 468 469 const int asid = 0; 470 const ThreadID tid = 0; 471 const Addr pc = thread->instAddr(); 472 unsigned block_size = dcachePort.peerBlockSize(); 473 BaseTLB::Mode mode = BaseTLB::Write; 474 475 if (traceData) { 476 traceData->setAddr(addr); 477 } 478 479 RequestPtr req = new Request(asid, addr, size, 480 flags, dataMasterId(), pc, _cpuId, tid); 481 482 Addr split_addr = roundDown(addr + size - 1, block_size); 483 assert(split_addr <= addr || split_addr - addr < block_size); 484 485 _status = DTBWaitResponse; 486 if (split_addr > addr) { 487 RequestPtr req1, req2; 488 assert(!req->isLLSC() && !req->isSwap()); 489 req->splitOnVaddr(split_addr, req1, req2); 490 491 WholeTranslationState *state = 492 new WholeTranslationState(req, req1, req2, newData, res, mode); 493 DataTranslation<TimingSimpleCPU *> *trans1 = 494 new DataTranslation<TimingSimpleCPU *>(this, state, 0); 495 DataTranslation<TimingSimpleCPU *> *trans2 = 496 new DataTranslation<TimingSimpleCPU *>(this, state, 1); 497 498 thread->dtb->translateTiming(req1, tc, trans1, mode); 499 thread->dtb->translateTiming(req2, tc, trans2, mode); 500 } else { 501 WholeTranslationState *state = 502 new WholeTranslationState(req, newData, res, mode); 503 DataTranslation<TimingSimpleCPU *> *translation = 504 new DataTranslation<TimingSimpleCPU *>(this, state); 505 thread->dtb->translateTiming(req, tc, translation, mode); 506 } 507 508 // Translation faults will be returned via finishTranslation() 509 return NoFault; 510} 511 512 513void 514TimingSimpleCPU::finishTranslation(WholeTranslationState *state) 515{ 516 _status = Running; 517 518 if (state->getFault() != NoFault) { 519 if (state->isPrefetch()) { 520 state->setNoFault(); 521 } 522 delete [] state->data; 523 state->deleteReqs(); 524 translationFault(state->getFault()); 525 } else { 526 if (!state->isSplit) { 527 sendData(state->mainReq, state->data, state->res, 528 state->mode == BaseTLB::Read); 529 } else { 530 sendSplitData(state->sreqLow, state->sreqHigh, state->mainReq, 531 state->data, state->mode == BaseTLB::Read); 532 } 533 } 534 535 delete state; 536} 537 538 539void 540TimingSimpleCPU::fetch() 541{ 542 DPRINTF(SimpleCPU, "Fetch\n"); 543 544 if (!curStaticInst || !curStaticInst->isDelayedCommit()) 545 checkForInterrupts(); 546 547 checkPcEventQueue(); 548 549 // We must have just got suspended by a PC event 550 if (_status == Idle) 551 return; 552 553 TheISA::PCState pcState = thread->pcState(); 554 bool needToFetch = !isRomMicroPC(pcState.microPC()) && !curMacroStaticInst; 555 556 if (needToFetch) { 557 _status = Running; 558 Request *ifetch_req = new Request(); 559 ifetch_req->setThreadContext(_cpuId, /* thread ID */ 0); 560 setupFetchRequest(ifetch_req); 561 DPRINTF(SimpleCPU, "Translating address %#x\n", ifetch_req->getVaddr()); 562 thread->itb->translateTiming(ifetch_req, tc, &fetchTranslation, 563 BaseTLB::Execute); 564 } else { 565 _status = IcacheWaitResponse; 566 completeIfetch(NULL); 567 568 numCycles += tickToCycles(curTick() - previousTick); 569 previousTick = curTick(); 570 } 571} 572 573 574void 575TimingSimpleCPU::sendFetch(Fault fault, RequestPtr req, ThreadContext *tc) 576{ 577 if (fault == NoFault) { 578 DPRINTF(SimpleCPU, "Sending fetch for addr %#x(pa: %#x)\n", 579 req->getVaddr(), req->getPaddr()); 580 ifetch_pkt = new Packet(req, MemCmd::ReadReq); 581 ifetch_pkt->dataStatic(&inst); 582 DPRINTF(SimpleCPU, " -- pkt addr: %#x\n", ifetch_pkt->getAddr()); 583 584 if (!icachePort.sendTiming(ifetch_pkt)) { 585 // Need to wait for retry 586 _status = IcacheRetry; 587 } else { 588 // Need to wait for cache to respond 589 _status = IcacheWaitResponse; 590 // ownership of packet transferred to memory system 591 ifetch_pkt = NULL; 592 } 593 } else { 594 DPRINTF(SimpleCPU, "Translation of addr %#x faulted\n", req->getVaddr()); 595 delete req; 596 // fetch fault: advance directly to next instruction (fault handler) 597 _status = Running; 598 advanceInst(fault); 599 } 600 601 numCycles += tickToCycles(curTick() - previousTick); 602 previousTick = curTick(); 603} 604 605 606void 607TimingSimpleCPU::advanceInst(Fault fault) 608{ 609 610 if (_status == Faulting) 611 return; 612 613 if (fault != NoFault) { 614 advancePC(fault); 615 DPRINTF(SimpleCPU, "Fault occured, scheduling fetch event\n"); 616 reschedule(fetchEvent, nextCycle(), true); 617 _status = Faulting; 618 return; 619 } 620 621 622 if (!stayAtPC) 623 advancePC(fault); 624 625 if (_status == Running) { 626 // kick off fetch of next instruction... callback from icache 627 // response will cause that instruction to be executed, 628 // keeping the CPU running. 629 fetch(); 630 } 631} 632 633 634void 635TimingSimpleCPU::completeIfetch(PacketPtr pkt) 636{ 637 DPRINTF(SimpleCPU, "Complete ICache Fetch for addr %#x\n", pkt ? 638 pkt->getAddr() : 0); 639 640 // received a response from the icache: execute the received 641 // instruction 642 643 assert(!pkt || !pkt->isError()); 644 assert(_status == IcacheWaitResponse); 645 646 _status = Running; 647 648 numCycles += tickToCycles(curTick() - previousTick); 649 previousTick = curTick(); 650 651 if (getState() == SimObject::Draining) { 652 if (pkt) { 653 delete pkt->req; 654 delete pkt; 655 } 656 657 completeDrain(); 658 return; 659 } 660 661 preExecute(); 662 if (curStaticInst && curStaticInst->isMemRef()) { 663 // load or store: just send to dcache 664 Fault fault = curStaticInst->initiateAcc(this, traceData); 665 666 // If we're not running now the instruction will complete in a dcache 667 // response callback or the instruction faulted and has started an 668 // ifetch 669 if (_status == Running) { 670 if (fault != NoFault && traceData) { 671 // If there was a fault, we shouldn't trace this instruction. 672 delete traceData; 673 traceData = NULL; 674 } 675 676 postExecute(); 677 // @todo remove me after debugging with legion done 678 if (curStaticInst && (!curStaticInst->isMicroop() || 679 curStaticInst->isFirstMicroop())) 680 instCnt++; 681 advanceInst(fault); 682 } 683 } else if (curStaticInst) { 684 // non-memory instruction: execute completely now 685 Fault fault = curStaticInst->execute(this, traceData); 686 687 // keep an instruction count 688 if (fault == NoFault) 689 countInst(); 690 else if (traceData && !DTRACE(ExecFaulting)) { 691 delete traceData; 692 traceData = NULL; 693 } 694 695 postExecute(); 696 // @todo remove me after debugging with legion done 697 if (curStaticInst && (!curStaticInst->isMicroop() || 698 curStaticInst->isFirstMicroop())) 699 instCnt++; 700 advanceInst(fault); 701 } else { 702 advanceInst(NoFault); 703 } 704 705 if (pkt) { 706 delete pkt->req; 707 delete pkt; 708 } 709} 710 711void 712TimingSimpleCPU::IcachePort::ITickEvent::process() 713{ 714 cpu->completeIfetch(pkt); 715} 716 717bool 718TimingSimpleCPU::IcachePort::recvTiming(PacketPtr pkt) 719{ 720 assert(pkt->isResponse()); 721 if (!pkt->wasNacked()) { 722 DPRINTF(SimpleCPU, "Received timing response %#x\n", pkt->getAddr()); 723 // delay processing of returned data until next CPU clock edge 724 Tick next_tick = cpu->nextCycle(curTick()); 725 726 if (next_tick == curTick()) 727 cpu->completeIfetch(pkt); 728 else 729 tickEvent.schedule(pkt, next_tick); 730 731 return true; 732 } else { 733 assert(cpu->_status == IcacheWaitResponse); 734 pkt->reinitNacked(); 735 if (!sendTiming(pkt)) { 736 cpu->_status = IcacheRetry; 737 cpu->ifetch_pkt = pkt; 738 } 739 } 740 741 return true; 742} 743 744void 745TimingSimpleCPU::IcachePort::recvRetry() 746{ 747 // we shouldn't get a retry unless we have a packet that we're 748 // waiting to transmit 749 assert(cpu->ifetch_pkt != NULL); 750 assert(cpu->_status == IcacheRetry); 751 PacketPtr tmp = cpu->ifetch_pkt; 752 if (sendTiming(tmp)) { 753 cpu->_status = IcacheWaitResponse; 754 cpu->ifetch_pkt = NULL; 755 } 756} 757 758void 759TimingSimpleCPU::completeDataAccess(PacketPtr pkt) 760{ 761 // received a response from the dcache: complete the load or store 762 // instruction 763 assert(!pkt->isError()); 764 assert(_status == DcacheWaitResponse || _status == DTBWaitResponse || 765 pkt->req->getFlags().isSet(Request::NO_ACCESS)); 766 767 numCycles += tickToCycles(curTick() - previousTick); 768 previousTick = curTick(); 769 770 if (pkt->senderState) { 771 SplitFragmentSenderState * send_state = 772 dynamic_cast<SplitFragmentSenderState *>(pkt->senderState); 773 assert(send_state); 774 delete pkt->req; 775 delete pkt; 776 PacketPtr big_pkt = send_state->bigPkt; 777 delete send_state; 778 779 SplitMainSenderState * main_send_state = 780 dynamic_cast<SplitMainSenderState *>(big_pkt->senderState); 781 assert(main_send_state); 782 // Record the fact that this packet is no longer outstanding. 783 assert(main_send_state->outstanding != 0); 784 main_send_state->outstanding--; 785 786 if (main_send_state->outstanding) { 787 return; 788 } else { 789 delete main_send_state; 790 big_pkt->senderState = NULL; 791 pkt = big_pkt; 792 } 793 } 794 795 _status = Running; 796 797 Fault fault = curStaticInst->completeAcc(pkt, this, traceData); 798 799 // keep an instruction count 800 if (fault == NoFault) 801 countInst(); 802 else if (traceData) { 803 // If there was a fault, we shouldn't trace this instruction. 804 delete traceData; 805 traceData = NULL; 806 } 807 808 // the locked flag may be cleared on the response packet, so check 809 // pkt->req and not pkt to see if it was a load-locked 810 if (pkt->isRead() && pkt->req->isLLSC()) { 811 TheISA::handleLockedRead(thread, pkt->req); 812 } 813 814 delete pkt->req; 815 delete pkt; 816 817 postExecute(); 818 819 if (getState() == SimObject::Draining) { 820 advancePC(fault); 821 completeDrain(); 822 823 return; 824 } 825 826 advanceInst(fault); 827} 828 829 830void 831TimingSimpleCPU::completeDrain() 832{ 833 DPRINTF(Config, "Done draining\n"); 834 changeState(SimObject::Drained); 835 drainEvent->process(); 836} 837 838bool 839TimingSimpleCPU::DcachePort::recvTiming(PacketPtr pkt) 840{ 841 assert(pkt->isResponse()); 842 if (!pkt->wasNacked()) { 843 // delay processing of returned data until next CPU clock edge 844 Tick next_tick = cpu->nextCycle(curTick()); 845 846 if (next_tick == curTick()) { 847 cpu->completeDataAccess(pkt); 848 } else { 849 if (!tickEvent.scheduled()) { 850 tickEvent.schedule(pkt, next_tick); 851 } else { 852 // In the case of a split transaction and a cache that is 853 // faster than a CPU we could get two responses before 854 // next_tick expires 855 if (!retryEvent.scheduled()) 856 cpu->schedule(retryEvent, next_tick); 857 return false; 858 } 859 } 860 861 return true; 862 } else { 863 assert(cpu->_status == DcacheWaitResponse); 864 pkt->reinitNacked(); 865 if (!sendTiming(pkt)) { 866 cpu->_status = DcacheRetry; 867 cpu->dcache_pkt = pkt; 868 } 869 } 870 871 return true; 872} 873 874void 875TimingSimpleCPU::DcachePort::DTickEvent::process() 876{ 877 cpu->completeDataAccess(pkt); 878} 879 880void 881TimingSimpleCPU::DcachePort::recvRetry() 882{ 883 // we shouldn't get a retry unless we have a packet that we're 884 // waiting to transmit 885 assert(cpu->dcache_pkt != NULL); 886 assert(cpu->_status == DcacheRetry); 887 PacketPtr tmp = cpu->dcache_pkt; 888 if (tmp->senderState) { 889 // This is a packet from a split access. 890 SplitFragmentSenderState * send_state = 891 dynamic_cast<SplitFragmentSenderState *>(tmp->senderState); 892 assert(send_state); 893 PacketPtr big_pkt = send_state->bigPkt; 894 895 SplitMainSenderState * main_send_state = 896 dynamic_cast<SplitMainSenderState *>(big_pkt->senderState); 897 assert(main_send_state); 898 899 if (sendTiming(tmp)) { 900 // If we were able to send without retrying, record that fact 901 // and try sending the other fragment. 902 send_state->clearFromParent(); 903 int other_index = main_send_state->getPendingFragment(); 904 if (other_index > 0) { 905 tmp = main_send_state->fragments[other_index]; 906 cpu->dcache_pkt = tmp; 907 if ((big_pkt->isRead() && cpu->handleReadPacket(tmp)) || 908 (big_pkt->isWrite() && cpu->handleWritePacket())) { 909 main_send_state->fragments[other_index] = NULL; 910 } 911 } else { 912 cpu->_status = DcacheWaitResponse; 913 // memory system takes ownership of packet 914 cpu->dcache_pkt = NULL; 915 } 916 } 917 } else if (sendTiming(tmp)) { 918 cpu->_status = DcacheWaitResponse; 919 // memory system takes ownership of packet 920 cpu->dcache_pkt = NULL; 921 } 922} 923 924TimingSimpleCPU::IprEvent::IprEvent(Packet *_pkt, TimingSimpleCPU *_cpu, 925 Tick t) 926 : pkt(_pkt), cpu(_cpu) 927{ 928 cpu->schedule(this, t); 929} 930 931void 932TimingSimpleCPU::IprEvent::process() 933{ 934 cpu->completeDataAccess(pkt); 935} 936 937const char * 938TimingSimpleCPU::IprEvent::description() const 939{ 940 return "Timing Simple CPU Delay IPR event"; 941} 942 943 944void 945TimingSimpleCPU::printAddr(Addr a) 946{ 947 dcachePort.printAddr(a); 948} 949 950 951//////////////////////////////////////////////////////////////////////// 952// 953// TimingSimpleCPU Simulation Object 954// 955TimingSimpleCPU * 956TimingSimpleCPUParams::create() 957{ 958 numThreads = 1; 959 if (!FullSystem && workload.size() != 1) 960 panic("only one workload allowed"); 961 return new TimingSimpleCPU(this); 962} 963