base.cc revision 4572 
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
69using namespace std;
70using namespace TheISA;
71
72BaseSimpleCPU::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
99BaseSimpleCPU::~BaseSimpleCPU()
100{
101}
102
103void
104BaseSimpleCPU::deallocateContext(int thread_num)
105{
106    // for now, these are equivalent
107    suspendContext(thread_num);
108}
109
110
111void
112BaseSimpleCPU::haltContext(int thread_num)
113{
114    // for now, these are equivalent
115    suspendContext(thread_num);
116}
117
118
119void
120BaseSimpleCPU::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
173void
174BaseSimpleCPU::resetStats()
175{
176//    startNumInst = numInst;
177    // notIdleFraction = (_status != Idle);
178}
179
180void
181BaseSimpleCPU::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
189void
190BaseSimpleCPU::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
197void
198change_thread_state(int thread_number, int activate, int priority)
199{
200}
201
202Fault
203BaseSimpleCPU::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
240Fault
241BaseSimpleCPU::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
293Addr
294BaseSimpleCPU::dbg_vtophys(Addr addr)
295{
296    return vtophys(tc, addr);
297}
298#endif // FULL_SYSTEM
299
300#if FULL_SYSTEM
301void
302BaseSimpleCPU::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
313void
314BaseSimpleCPU::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
329Fault
330BaseSimpleCPU::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\n",threadPC,
340            thread->readNextPC());
341#endif
342
343    Addr fetchPC = (threadPC & PCMask) + fetchOffset;
344    req->setVirt(0, fetchPC, sizeof(MachInst), 0, threadPC);
345
346    Fault fault = thread->translateInstReq(req);
347
348    return fault;
349}
350
351
352void
353BaseSimpleCPU::preExecute()
354{
355    // maintain $r0 semantics
356    thread->setIntReg(ZeroReg, 0);
357#if THE_ISA == ALPHA_ISA
358    thread->setFloatReg(ZeroReg, 0.0);
359#endif // ALPHA_ISA
360
361    // keep an instruction count
362    numInst++;
363    numInsts++;
364
365    thread->funcExeInst++;
366
367    // check for instruction-count-based events
368    comInstEventQueue[0]->serviceEvents(numInst);
369
370    // decode the instruction
371    inst = gtoh(inst);
372
373    //If we're not in the middle of a macro instruction
374    if (!curMacroStaticInst) {
375
376        StaticInstPtr instPtr = NULL;
377
378        //Predecode, ie bundle up an ExtMachInst
379        //This should go away once the constructor can be set up properly
380        predecoder.setTC(thread->getTC());
381        //If more fetch data is needed, pass it in.
382        if(predecoder.needMoreBytes())
383            predecoder.moreBytes(thread->readPC(),
384                    (thread->readPC() & PCMask) + 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                                         thread->readPC());
397        } else {
398            stayAtPC = true;
399            fetchOffset += sizeof(MachInst);
400        }
401
402        //If we decoded an instruction and it's microcoded, start pulling
403        //out micro ops
404        if (instPtr && instPtr->isMacroop()) {
405            curMacroStaticInst = instPtr;
406            curStaticInst = curMacroStaticInst->
407                fetchMicroop(thread->readMicroPC());
408        } else {
409            curStaticInst = instPtr;
410        }
411    } else {
412        //Read the next micro op from the macro op
413        curStaticInst = curMacroStaticInst->
414            fetchMicroop(thread->readMicroPC());
415    }
416
417    //If we decoded an instruction this "tick", record information about it.
418    if(curStaticInst)
419    {
420#if TRACING_ON
421        traceData = Trace::getInstRecord(curTick, tc, curStaticInst,
422                                         thread->readPC());
423
424        DPRINTF(Decode,"Decode: Decoded %s instruction: 0x%x\n",
425                curStaticInst->getName(), curStaticInst->machInst);
426#endif // TRACING_ON
427
428#if FULL_SYSTEM
429        thread->setInst(inst);
430#endif // FULL_SYSTEM
431    }
432}
433
434void
435BaseSimpleCPU::postExecute()
436{
437#if FULL_SYSTEM
438    if (thread->profile) {
439        bool usermode = TheISA::inUserMode(tc);
440        thread->profilePC = usermode ? 1 : thread->readPC();
441        StaticInstPtr si(inst, thread->readPC());
442        ProfileNode *node = thread->profile->consume(tc, si);
443        if (node)
444            thread->profileNode = node;
445    }
446#endif
447
448    if (curStaticInst->isMemRef()) {
449        numMemRefs++;
450    }
451
452    if (curStaticInst->isLoad()) {
453        ++numLoad;
454        comLoadEventQueue[0]->serviceEvents(numLoad);
455    }
456
457    traceFunctions(thread->readPC());
458
459    if (traceData) {
460        traceData->dump();
461        delete traceData;
462        traceData = NULL;
463    }
464}
465
466
467void
468BaseSimpleCPU::advancePC(Fault fault)
469{
470    //Since we're moving to a new pc, zero out the offset
471    fetchOffset = 0;
472    if (fault != NoFault) {
473        curMacroStaticInst = StaticInst::nullStaticInstPtr;
474        fault->invoke(tc);
475        thread->setMicroPC(0);
476        thread->setNextMicroPC(1);
477    } else {
478        //If we're at the last micro op for this instruction
479        if (curStaticInst && curStaticInst->isLastMicroop()) {
480            //We should be working with a macro op
481            assert(curMacroStaticInst);
482            //Close out this macro op, and clean up the
483            //microcode state
484            curMacroStaticInst = StaticInst::nullStaticInstPtr;
485            thread->setMicroPC(0);
486            thread->setNextMicroPC(1);
487        }
488        //If we're still in a macro op
489        if (curMacroStaticInst) {
490            //Advance the micro pc
491            thread->setMicroPC(thread->readNextMicroPC());
492            //Advance the "next" micro pc. Note that there are no delay
493            //slots, and micro ops are "word" addressed.
494            thread->setNextMicroPC(thread->readNextMicroPC() + 1);
495        } else {
496            // go to the next instruction
497            thread->setPC(thread->readNextPC());
498            thread->setNextPC(thread->readNextNPC());
499            thread->setNextNPC(thread->readNextNPC() + sizeof(MachInst));
500            assert(thread->readNextPC() != thread->readNextNPC());
501        }
502    }
503
504#if FULL_SYSTEM
505    Addr oldpc;
506    do {
507        oldpc = thread->readPC();
508        system->pcEventQueue.service(tc);
509    } while (oldpc != thread->readPC());
510#endif
511}
512
513