src/cpu/simple/base.cc

   1 /*
   2  * Copyright (c) 2002-2005 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: Steve Reinhardt
  29  */
  30
  31 #include "arch/utility.hh"
  32 #include "arch/faults.hh"
  33 #include "base/cprintf.hh"
  34 #include "base/inifile.hh"
  35 #include "base/loader/symtab.hh"
  36 #include "base/misc.hh"
  37 #include "base/pollevent.hh"
  38 #include "base/range.hh"
  39 #include "base/stats/events.hh"
  40 #include "base/trace.hh"
  41 #include "cpu/base.hh"
  42 #include "cpu/exetrace.hh"
  43 #include "cpu/profile.hh"
  44 #include "cpu/simple/base.hh"
  45 #include "cpu/simple_thread.hh"
  46 #include "cpu/smt.hh"
  47 #include "cpu/static_inst.hh"
  48 #include "cpu/thread_context.hh"
  49 #include "mem/packet.hh"
  50 #include "sim/builder.hh"
  51 #include "sim/byteswap.hh"
  52 #include "sim/debug.hh"
  53 #include "sim/host.hh"
  54 #include "sim/sim_events.hh"
  55 #include "sim/sim_object.hh"
  56 #include "sim/stats.hh"
  57 #include "sim/system.hh"
  58
  59 #if FULL_SYSTEM
  60 #include "arch/kernel_stats.hh"
  61 #include "arch/stacktrace.hh"
  62 #include "arch/tlb.hh"
  63 #include "arch/vtophys.hh"
  64 #include "base/remote_gdb.hh"
  65 #else // !FULL_SYSTEM
  66 #include "mem/mem_object.hh"
  67 #endif // FULL_SYSTEM
  68
  69 using namespace std;
  70 using namespace TheISA;
  71
  72 BaseSimpleCPU::BaseSimpleCPU(Params *p)
  73     : BaseCPU(p), traceData(NULL), thread(NULL), predecoder(NULL)
  74 {
  75 #if FULL_SYSTEM
  76     thread = new SimpleThread(this, 0, p->system, p->itb, p->dtb);
  77 #else
  78     thread = new SimpleThread(this, /* thread_num */ 0, p->process,
  79             /* asid */ 0);
  80 #endif // !FULL_SYSTEM
  81
  82     thread->setStatus(ThreadContext::Unallocated);
  83
  84     tc = thread->getTC();
  85
  86     numInst = 0;
  87     startNumInst = 0;
  88     numLoad = 0;
  89     startNumLoad = 0;
  90     lastIcacheStall = 0;
  91     lastDcacheStall = 0;
  92
  93     threadContexts.push_back(tc);
  94
  95     fetchOffset = 0;
  96     stayAtPC = false;
  97 }
  98
  99 BaseSimpleCPU::~BaseSimpleCPU()
 100 {
 101 }
 102
 103 void
 104 BaseSimpleCPU::deallocateContext(int thread_num)
 105 {
 106     // for now, these are equivalent
 107     suspendContext(thread_num);
 108 }
 109
 110
 111 void
 112 BaseSimpleCPU::haltContext(int thread_num)
 113 {
 114     // for now, these are equivalent
 115     suspendContext(thread_num);
 116 }
 117
 118
 119 void
 120 BaseSimpleCPU::regStats()
 121 {
 122     using namespace Stats;
 123
 124     BaseCPU::regStats();
 125
 126     numInsts
 127         .name(name() + ".num_insts")
 128         .desc("Number of instructions executed")
 129         ;
 130
 131     numMemRefs
 132         .name(name() + ".num_refs")
 133         .desc("Number of memory references")
 134         ;
 135
 136     notIdleFraction
 137         .name(name() + ".not_idle_fraction")
 138         .desc("Percentage of non-idle cycles")
 139         ;
 140
 141     idleFraction
 142         .name(name() + ".idle_fraction")
 143         .desc("Percentage of idle cycles")
 144         ;
 145
 146     icacheStallCycles
 147         .name(name() + ".icache_stall_cycles")
 148         .desc("ICache total stall cycles")
 149         .prereq(icacheStallCycles)
 150         ;
 151
 152     dcacheStallCycles
 153         .name(name() + ".dcache_stall_cycles")
 154         .desc("DCache total stall cycles")
 155         .prereq(dcacheStallCycles)
 156         ;
 157
 158     icacheRetryCycles
 159         .name(name() + ".icache_retry_cycles")
 160         .desc("ICache total retry cycles")
 161         .prereq(icacheRetryCycles)
 162         ;
 163
 164     dcacheRetryCycles
 165         .name(name() + ".dcache_retry_cycles")
 166         .desc("DCache total retry cycles")
 167         .prereq(dcacheRetryCycles)
 168         ;
 169
 170     idleFraction = constant(1.0) - notIdleFraction;
 171 }
 172
 173 void
 174 BaseSimpleCPU::resetStats()
 175 {
 176 //    startNumInst = numInst;
 177     // notIdleFraction = (_status != Idle);
 178 }
 179
 180 void
 181 BaseSimpleCPU::serialize(ostream &os)
 182 {
 183     BaseCPU::serialize(os);
 184 //    SERIALIZE_SCALAR(inst);
 185     nameOut(os, csprintf("%s.xc.0", name()));
 186     thread->serialize(os);
 187 }
 188
 189 void
 190 BaseSimpleCPU::unserialize(Checkpoint *cp, const string &section)
 191 {
 192     BaseCPU::unserialize(cp, section);
 193 //    UNSERIALIZE_SCALAR(inst);
 194     thread->unserialize(cp, csprintf("%s.xc.0", section));
 195 }
 196
 197 void
 198 change_thread_state(int thread_number, int activate, int priority)
 199 {
 200 }
 201
 202 Fault
 203 BaseSimpleCPU::copySrcTranslate(Addr src)
 204 {
 205 #if 0
 206     static bool no_warn = true;
 207     int blk_size = (dcacheInterface) ? dcacheInterface->getBlockSize() : 64;
 208     // Only support block sizes of 64 atm.
 209     assert(blk_size == 64);
 210     int offset = src & (blk_size - 1);
 211
 212     // Make sure block doesn't span page
 213     if (no_warn &&
 214         (src & PageMask) != ((src + blk_size) & PageMask) &&
 215         (src >> 40) != 0xfffffc) {
 216         warn("Copied block source spans pages %x.", src);
 217         no_warn = false;
 218     }
 219
 220     memReq->reset(src & ~(blk_size - 1), blk_size);
 221
 222     // translate to physical address
 223     Fault fault = thread->translateDataReadReq(req);
 224
 225     if (fault == NoFault) {
 226         thread->copySrcAddr = src;
 227         thread->copySrcPhysAddr = memReq->paddr + offset;
 228     } else {
 229         assert(!fault->isAlignmentFault());
 230
 231         thread->copySrcAddr = 0;
 232         thread->copySrcPhysAddr = 0;
 233     }
 234     return fault;
 235 #else
 236     return NoFault;
 237 #endif
 238 }
 239
 240 Fault
 241 BaseSimpleCPU::copy(Addr dest)
 242 {
 243 #if 0
 244     static bool no_warn = true;
 245     int blk_size = (dcacheInterface) ? dcacheInterface->getBlockSize() : 64;
 246     // Only support block sizes of 64 atm.
 247     assert(blk_size == 64);
 248     uint8_t data[blk_size];
 249     //assert(thread->copySrcAddr);
 250     int offset = dest & (blk_size - 1);
 251
 252     // Make sure block doesn't span page
 253     if (no_warn &&
 254         (dest & PageMask) != ((dest + blk_size) & PageMask) &&
 255         (dest >> 40) != 0xfffffc) {
 256         no_warn = false;
 257         warn("Copied block destination spans pages %x. ", dest);
 258     }
 259
 260     memReq->reset(dest & ~(blk_size -1), blk_size);
 261     // translate to physical address
 262     Fault fault = thread->translateDataWriteReq(req);
 263
 264     if (fault == NoFault) {
 265         Addr dest_addr = memReq->paddr + offset;
 266         // Need to read straight from memory since we have more than 8 bytes.
 267         memReq->paddr = thread->copySrcPhysAddr;
 268         thread->mem->read(memReq, data);
 269         memReq->paddr = dest_addr;
 270         thread->mem->write(memReq, data);
 271         if (dcacheInterface) {
 272             memReq->cmd = Copy;
 273             memReq->completionEvent = NULL;
 274             memReq->paddr = thread->copySrcPhysAddr;
 275             memReq->dest = dest_addr;
 276             memReq->size = 64;
 277             memReq->time = curTick;
 278             memReq->flags &= ~INST_READ;
 279             dcacheInterface->access(memReq);
 280         }
 281     }
 282     else
 283         assert(!fault->isAlignmentFault());
 284
 285     return fault;
 286 #else
 287     panic("copy not implemented");
 288     return NoFault;
 289 #endif
 290 }
 291
 292 #if FULL_SYSTEM
 293 Addr
 294 BaseSimpleCPU::dbg_vtophys(Addr addr)
 295 {
 296     return vtophys(tc, addr);
 297 }
 298 #endif // FULL_SYSTEM
 299
 300 #if FULL_SYSTEM
 301 void
 302 BaseSimpleCPU::post_interrupt(int int_num, int index)
 303 {
 304     BaseCPU::post_interrupt(int_num, index);
 305
 306     if (thread->status() == ThreadContext::Suspended) {
 307                 DPRINTF(Quiesce,"Suspended Processor awoke\n");
 308         thread->activate();
 309     }
 310 }
 311 #endif // FULL_SYSTEM
 312
 313 void
 314 BaseSimpleCPU::checkForInterrupts()
 315 {
 316 #if FULL_SYSTEM
 317     if (check_interrupts(tc)) {
 318         Fault interrupt = interrupts.getInterrupt(tc);
 319
 320         if (interrupt != NoFault) {
 321             interrupts.updateIntrInfo(tc);
 322             interrupt->invoke(tc);
 323         }
 324     }
 325 #endif
 326 }
 327
 328
 329 Fault
 330 BaseSimpleCPU::setupFetchRequest(Request *req)
 331 {
 332     Addr threadPC = thread->readPC();
 333
 334     // set up memory request for instruction fetch
 335 #if ISA_HAS_DELAY_SLOT
 336     DPRINTF(Fetch,"Fetch: PC:%08p NPC:%08p NNPC:%08p\n",threadPC,
 337             thread->readNextPC(),thread->readNextNPC());
 338 #else
 339     DPRINTF(Fetch,"Fetch: PC:%08p NPC:%08p",threadPC,
 340             thread->readNextPC());
 341 #endif
 342
 343     const Addr PCMask = ~((Addr)sizeof(MachInst) - 1);
 344     Addr fetchPC = threadPC + fetchOffset;
 345     req->setVirt(0, fetchPC & PCMask, sizeof(MachInst), 0, threadPC);
 346
 347     Fault fault = thread->translateInstReq(req);
 348
 349     return fault;
 350 }
 351
 352
 353 void
 354 BaseSimpleCPU::preExecute()
 355 {
 356     // maintain $r0 semantics
 357     thread->setIntReg(ZeroReg, 0);
 358 #if THE_ISA == ALPHA_ISA
 359     thread->setFloatReg(ZeroReg, 0.0);
 360 #endif // ALPHA_ISA
 361
 362     // keep an instruction count
 363     numInst++;
 364     numInsts++;
 365
 366     thread->funcExeInst++;
 367
 368     // check for instruction-count-based events
 369     comInstEventQueue[0]->serviceEvents(numInst);
 370
 371     // decode the instruction
 372     inst = gtoh(inst);
 373
 374     //If we're not in the middle of a macro instruction
 375     if (!curMacroStaticInst) {
 376
 377         StaticInstPtr instPtr = NULL;
 378
 379         //Predecode, ie bundle up an ExtMachInst
 380         //This should go away once the constructor can be set up properly
 381         predecoder.setTC(thread->getTC());
 382         //If more fetch data is needed, pass it in.
 383         if(predecoder.needMoreBytes())
 384             predecoder.moreBytes(thread->readPC() + fetchOffset, 0, inst);
 385         else
 386             predecoder.process();
 387
 388         //If an instruction is ready, decode it. Otherwise, we'll have to
 389         //fetch beyond the MachInst at the current pc.
 390         if (predecoder.extMachInstReady()) {
 391 #if THE_ISA == X86_ISA
 392             thread->setNextPC(thread->readPC() + predecoder.getInstSize());
 393 #endif // X86_ISA
 394             stayAtPC = false;
 395             instPtr = StaticInst::decode(predecoder.getExtMachInst());
 396         } else {
 397             stayAtPC = true;
 398             fetchOffset += sizeof(MachInst);
 399         }
 400
 401         //If we decoded an instruction and it's microcoded, start pulling
 402         //out micro ops
 403         if (instPtr && instPtr->isMacroOp()) {
 404             curMacroStaticInst = instPtr;
 405             curStaticInst = curMacroStaticInst->
 406                 fetchMicroOp(thread->readMicroPC());
 407         } else {
 408             curStaticInst = instPtr;
 409         }
 410     } else {
 411         //Read the next micro op from the macro op
 412         curStaticInst = curMacroStaticInst->
 413             fetchMicroOp(thread->readMicroPC());
 414     }
 415
 416     //If we decoded an instruction this "tick", record information about it.
 417     if(curStaticInst)
 418     {
 419 #if TRACING_ON
 420         traceData = Trace::getInstRecord(curTick, tc, curStaticInst,
 421                                          thread->readPC());
 422
 423         DPRINTF(Decode,"Decode: Decoded %s instruction: 0x%x\n",
 424                 curStaticInst->getName(), curStaticInst->machInst);
 425 #endif // TRACING_ON
 426
 427 #if FULL_SYSTEM
 428         thread->setInst(inst);
 429 #endif // FULL_SYSTEM
 430     }
 431 }
 432
 433 void
 434 BaseSimpleCPU::postExecute()
 435 {
 436 #if FULL_SYSTEM
 437     if (thread->profile) {
 438         bool usermode = TheISA::inUserMode(tc);
 439         thread->profilePC = usermode ? 1 : thread->readPC();
 440         StaticInstPtr si(inst);
 441         ProfileNode *node = thread->profile->consume(tc, si);
 442         if (node)
 443             thread->profileNode = node;
 444     }
 445 #endif
 446
 447     if (curStaticInst->isMemRef()) {
 448         numMemRefs++;
 449     }
 450
 451     if (curStaticInst->isLoad()) {
 452         ++numLoad;
 453         comLoadEventQueue[0]->serviceEvents(numLoad);
 454     }
 455
 456     traceFunctions(thread->readPC());
 457
 458     if (traceData) {
 459         traceData->dump();
 460         delete traceData;
 461         traceData = NULL;
 462     }
 463 }
 464
 465
 466 void
 467 BaseSimpleCPU::advancePC(Fault fault)
 468 {
 469     //Since we're moving to a new pc, zero out the offset
 470     fetchOffset = 0;
 471     if (fault != NoFault) {
 472         curMacroStaticInst = StaticInst::nullStaticInstPtr;
 473         fault->invoke(tc);
 474         thread->setMicroPC(0);
 475         thread->setNextMicroPC(1);
 476     } else {
 477         //If we're at the last micro op for this instruction
 478         if (curStaticInst && curStaticInst->isLastMicroOp()) {
 479             //We should be working with a macro op
 480             assert(curMacroStaticInst);
 481             //Close out this macro op, and clean up the
 482             //microcode state
 483             curMacroStaticInst = StaticInst::nullStaticInstPtr;
 484             thread->setMicroPC(0);
 485             thread->setNextMicroPC(1);
 486         }
 487         //If we're still in a macro op
 488         if (curMacroStaticInst) {
 489             //Advance the micro pc
 490             thread->setMicroPC(thread->readNextMicroPC());
 491             //Advance the "next" micro pc. Note that there are no delay
 492             //slots, and micro ops are "word" addressed.
 493             thread->setNextMicroPC(thread->readNextMicroPC() + 1);
 494         } else {
 495             // go to the next instruction
 496             thread->setPC(thread->readNextPC());
 497             thread->setNextPC(thread->readNextNPC());
 498             thread->setNextNPC(thread->readNextNPC() + sizeof(MachInst));
 499             assert(thread->readNextPC() != thread->readNextNPC());
 500         }
 501     }
 502
 503 #if FULL_SYSTEM
 504     Addr oldpc;
 505     do {
 506         oldpc = thread->readPC();
 507         system->pcEventQueue.service(tc);
 508     } while (oldpc != thread->readPC());
 509 #endif
 510 }
 511