1/*
2 * Copyright (c) 2001-2005 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: Nathan Binkert
29 * Steve Reinhardt
30 * Andrew Schultz
31 */
32
33#include <string>
34#include <vector>
35
36#include "arch/alpha/pagetable.hh"
37#include "arch/alpha/tlb.hh"
38#include "arch/alpha/faults.hh"
39#include "base/inifile.hh"
40#include "base/str.hh"
41#include "base/trace.hh"
42#include "config/alpha_tlaser.hh"
43#include "cpu/thread_context.hh"
|
46
47using namespace std;
48using namespace EV5;
49
50namespace AlphaISA {
51///////////////////////////////////////////////////////////////////////
52//
53// Alpha TLB
54//
55#ifdef DEBUG
56bool uncacheBit39 = false;
57bool uncacheBit40 = false;
58#endif
59
60#define MODE2MASK(X) (1 << (X))
61
62TLB::TLB(const string &name, int s)
63 : SimObject(name), size(s), nlu(0)
64{
65 table = new PTE[size];
66 memset(table, 0, sizeof(PTE[size]));
67}
68
69TLB::~TLB()
70{
71 if (table)
72 delete [] table;
73}
74
75// look up an entry in the TLB
76PTE *
77TLB::lookup(Addr vpn, uint8_t asn) const
78{
79 // assume not found...
80 PTE *retval = NULL;
81
82 PageTable::const_iterator i = lookupTable.find(vpn);
83 if (i != lookupTable.end()) {
84 while (i->first == vpn) {
85 int index = i->second;
86 PTE *pte = &table[index];
87 assert(pte->valid);
88 if (vpn == pte->tag && (pte->asma || pte->asn == asn)) {
89 retval = pte;
90 break;
91 }
92
93 ++i;
94 }
95 }
96
97 DPRINTF(TLB, "lookup %#x, asn %#x -> %s ppn %#x\n", vpn, (int)asn,
98 retval ? "hit" : "miss", retval ? retval->ppn : 0);
99 return retval;
100}
101
102
103Fault
104TLB::checkCacheability(RequestPtr &req)
105{
106// in Alpha, cacheability is controlled by upper-level bits of the
107// physical address
108
109/*
110 * We support having the uncacheable bit in either bit 39 or bit 40.
111 * The Turbolaser platform (and EV5) support having the bit in 39, but
112 * Tsunami (which Linux assumes uses an EV6) generates accesses with
113 * the bit in 40. So we must check for both, but we have debug flags
114 * to catch a weird case where both are used, which shouldn't happen.
115 */
116
117
118#if ALPHA_TLASER
119 if (req->getPaddr() & PAddrUncachedBit39)
120#else
121 if (req->getPaddr() & PAddrUncachedBit43)
122#endif
123 {
124 // IPR memory space not implemented
125 if (PAddrIprSpace(req->getPaddr())) {
126 return new UnimpFault("IPR memory space not implemented!");
127 } else {
128 // mark request as uncacheable
129 req->setFlags(req->getFlags() | UNCACHEABLE);
130
131#if !ALPHA_TLASER
132 // Clear bits 42:35 of the physical address (10-2 in Tsunami manual)
133 req->setPaddr(req->getPaddr() & PAddrUncachedMask);
134#endif
135 }
136 }
137 return NoFault;
138}
139
140
141// insert a new TLB entry
142void
143TLB::insert(Addr addr, PTE &pte)
144{
145 VAddr vaddr = addr;
146 if (table[nlu].valid) {
147 Addr oldvpn = table[nlu].tag;
148 PageTable::iterator i = lookupTable.find(oldvpn);
149
150 if (i == lookupTable.end())
151 panic("TLB entry not found in lookupTable");
152
153 int index;
154 while ((index = i->second) != nlu) {
155 if (table[index].tag != oldvpn)
156 panic("TLB entry not found in lookupTable");
157
158 ++i;
159 }
160
161 DPRINTF(TLB, "remove @%d: %#x -> %#x\n", nlu, oldvpn, table[nlu].ppn);
162
163 lookupTable.erase(i);
164 }
165
166 DPRINTF(TLB, "insert @%d: %#x -> %#x\n", nlu, vaddr.vpn(), pte.ppn);
167
168 table[nlu] = pte;
169 table[nlu].tag = vaddr.vpn();
170 table[nlu].valid = true;
171
172 lookupTable.insert(make_pair(vaddr.vpn(), nlu));
173 nextnlu();
174}
175
176void
177TLB::flushAll()
178{
179 DPRINTF(TLB, "flushAll\n");
180 memset(table, 0, sizeof(PTE[size]));
181 lookupTable.clear();
182 nlu = 0;
183}
184
185void
186TLB::flushProcesses()
187{
188 PageTable::iterator i = lookupTable.begin();
189 PageTable::iterator end = lookupTable.end();
190 while (i != end) {
191 int index = i->second;
192 PTE *pte = &table[index];
193 assert(pte->valid);
194
195 // we can't increment i after we erase it, so save a copy and
196 // increment it to get the next entry now
197 PageTable::iterator cur = i;
198 ++i;
199
200 if (!pte->asma) {
201 DPRINTF(TLB, "flush @%d: %#x -> %#x\n", index, pte->tag, pte->ppn);
202 pte->valid = false;
203 lookupTable.erase(cur);
204 }
205 }
206}
207
208void
209TLB::flushAddr(Addr addr, uint8_t asn)
210{
211 VAddr vaddr = addr;
212
213 PageTable::iterator i = lookupTable.find(vaddr.vpn());
214 if (i == lookupTable.end())
215 return;
216
217 while (i != lookupTable.end() && i->first == vaddr.vpn()) {
218 int index = i->second;
219 PTE *pte = &table[index];
220 assert(pte->valid);
221
222 if (vaddr.vpn() == pte->tag && (pte->asma || pte->asn == asn)) {
223 DPRINTF(TLB, "flushaddr @%d: %#x -> %#x\n", index, vaddr.vpn(),
224 pte->ppn);
225
226 // invalidate this entry
227 pte->valid = false;
228
229 lookupTable.erase(i++);
230 } else {
231 ++i;
232 }
233 }
234}
235
236
237void
238TLB::serialize(ostream &os)
239{
240 SERIALIZE_SCALAR(size);
241 SERIALIZE_SCALAR(nlu);
242
243 for (int i = 0; i < size; i++) {
244 nameOut(os, csprintf("%s.PTE%d", name(), i));
245 table[i].serialize(os);
246 }
247}
248
249void
250TLB::unserialize(Checkpoint *cp, const string §ion)
251{
252 UNSERIALIZE_SCALAR(size);
253 UNSERIALIZE_SCALAR(nlu);
254
255 for (int i = 0; i < size; i++) {
256 table[i].unserialize(cp, csprintf("%s.PTE%d", section, i));
257 if (table[i].valid) {
258 lookupTable.insert(make_pair(table[i].tag, i));
259 }
260 }
261}
262
263
264///////////////////////////////////////////////////////////////////////
265//
266// Alpha ITB
267//
268ITB::ITB(const std::string &name, int size)
269 : TLB(name, size)
270{}
271
272
273void
274ITB::regStats()
275{
276 hits
277 .name(name() + ".hits")
278 .desc("ITB hits");
279 misses
280 .name(name() + ".misses")
281 .desc("ITB misses");
282 acv
283 .name(name() + ".acv")
284 .desc("ITB acv");
285 accesses
286 .name(name() + ".accesses")
287 .desc("ITB accesses");
288
289 accesses = hits + misses;
290}
291
292
293Fault
294ITB::translate(RequestPtr &req, ThreadContext *tc) const
295{
296 //If this is a pal pc, then set PHYSICAL
297 if(FULL_SYSTEM && PcPAL(req->getPC()))
298 req->setFlags(req->getFlags() | PHYSICAL);
299
300 if (PcPAL(req->getPC())) {
301 // strip off PAL PC marker (lsb is 1)
302 req->setPaddr((req->getVaddr() & ~3) & PAddrImplMask);
303 hits++;
304 return NoFault;
305 }
306
307 if (req->getFlags() & PHYSICAL) {
308 req->setPaddr(req->getVaddr());
309 } else {
310 // verify that this is a good virtual address
311 if (!validVirtualAddress(req->getVaddr())) {
312 acv++;
313 return new ItbAcvFault(req->getVaddr());
314 }
315
316
317 // VA<42:41> == 2, VA<39:13> maps directly to PA<39:13> for EV5
318 // VA<47:41> == 0x7e, VA<40:13> maps directly to PA<40:13> for EV6
319#if ALPHA_TLASER
320 if ((MCSR_SP(tc->readMiscRegNoEffect(IPR_MCSR)) & 2) &&
321 VAddrSpaceEV5(req->getVaddr()) == 2)
322#else
323 if (VAddrSpaceEV6(req->getVaddr()) == 0x7e)
324#endif
325 {
326 // only valid in kernel mode
327 if (ICM_CM(tc->readMiscRegNoEffect(IPR_ICM)) !=
328 mode_kernel) {
329 acv++;
330 return new ItbAcvFault(req->getVaddr());
331 }
332
333 req->setPaddr(req->getVaddr() & PAddrImplMask);
334
335#if !ALPHA_TLASER
336 // sign extend the physical address properly
337 if (req->getPaddr() & PAddrUncachedBit40)
338 req->setPaddr(req->getPaddr() | ULL(0xf0000000000));
339 else
340 req->setPaddr(req->getPaddr() & ULL(0xffffffffff));
341#endif
342
343 } else {
344 // not a physical address: need to look up pte
345 int asn = DTB_ASN_ASN(tc->readMiscRegNoEffect(IPR_DTB_ASN));
346 PTE *pte = lookup(VAddr(req->getVaddr()).vpn(),
347 asn);
348
349 if (!pte) {
350 misses++;
351 return new ItbPageFault(req->getVaddr());
352 }
353
354 req->setPaddr((pte->ppn << PageShift) +
355 (VAddr(req->getVaddr()).offset()
356 & ~3));
357
358 // check permissions for this access
359 if (!(pte->xre &
360 (1 << ICM_CM(tc->readMiscRegNoEffect(IPR_ICM))))) {
361 // instruction access fault
362 acv++;
363 return new ItbAcvFault(req->getVaddr());
364 }
365
366 hits++;
367 }
368 }
369
370 // check that the physical address is ok (catch bad physical addresses)
371 if (req->getPaddr() & ~PAddrImplMask)
372 return genMachineCheckFault();
373
374 return checkCacheability(req);
375
376}
377
378///////////////////////////////////////////////////////////////////////
379//
380// Alpha DTB
381//
382 DTB::DTB(const std::string &name, int size)
383 : TLB(name, size)
384{}
385
386void
387DTB::regStats()
388{
389 read_hits
390 .name(name() + ".read_hits")
391 .desc("DTB read hits")
392 ;
393
394 read_misses
395 .name(name() + ".read_misses")
396 .desc("DTB read misses")
397 ;
398
399 read_acv
400 .name(name() + ".read_acv")
401 .desc("DTB read access violations")
402 ;
403
404 read_accesses
405 .name(name() + ".read_accesses")
406 .desc("DTB read accesses")
407 ;
408
409 write_hits
410 .name(name() + ".write_hits")
411 .desc("DTB write hits")
412 ;
413
414 write_misses
415 .name(name() + ".write_misses")
416 .desc("DTB write misses")
417 ;
418
419 write_acv
420 .name(name() + ".write_acv")
421 .desc("DTB write access violations")
422 ;
423
424 write_accesses
425 .name(name() + ".write_accesses")
426 .desc("DTB write accesses")
427 ;
428
429 hits
430 .name(name() + ".hits")
431 .desc("DTB hits")
432 ;
433
434 misses
435 .name(name() + ".misses")
436 .desc("DTB misses")
437 ;
438
439 acv
440 .name(name() + ".acv")
441 .desc("DTB access violations")
442 ;
443
444 accesses
445 .name(name() + ".accesses")
446 .desc("DTB accesses")
447 ;
448
449 hits = read_hits + write_hits;
450 misses = read_misses + write_misses;
451 acv = read_acv + write_acv;
452 accesses = read_accesses + write_accesses;
453}
454
455Fault
456DTB::translate(RequestPtr &req, ThreadContext *tc, bool write) const
457{
458 Addr pc = tc->readPC();
459
460 mode_type mode =
461 (mode_type)DTB_CM_CM(tc->readMiscRegNoEffect(IPR_DTB_CM));
462
463
464 /**
465 * Check for alignment faults
466 */
467 if (req->getVaddr() & (req->getSize() - 1)) {
468 DPRINTF(TLB, "Alignment Fault on %#x, size = %d", req->getVaddr(),
469 req->getSize());
470 uint64_t flags = write ? MM_STAT_WR_MASK : 0;
471 return new DtbAlignmentFault(req->getVaddr(), req->getFlags(), flags);
472 }
473
474 if (PcPAL(pc)) {
475 mode = (req->getFlags() & ALTMODE) ?
476 (mode_type)ALT_MODE_AM(
477 tc->readMiscRegNoEffect(IPR_ALT_MODE))
478 : mode_kernel;
479 }
480
481 if (req->getFlags() & PHYSICAL) {
482 req->setPaddr(req->getVaddr());
483 } else {
484 // verify that this is a good virtual address
485 if (!validVirtualAddress(req->getVaddr())) {
486 if (write) { write_acv++; } else { read_acv++; }
487 uint64_t flags = (write ? MM_STAT_WR_MASK : 0) |
488 MM_STAT_BAD_VA_MASK |
489 MM_STAT_ACV_MASK;
490 return new DtbPageFault(req->getVaddr(), req->getFlags(), flags);
491 }
492
493 // Check for "superpage" mapping
494#if ALPHA_TLASER
495 if ((MCSR_SP(tc->readMiscRegNoEffect(IPR_MCSR)) & 2) &&
496 VAddrSpaceEV5(req->getVaddr()) == 2)
497#else
498 if (VAddrSpaceEV6(req->getVaddr()) == 0x7e)
499#endif
500 {
501
502 // only valid in kernel mode
503 if (DTB_CM_CM(tc->readMiscRegNoEffect(IPR_DTB_CM)) !=
504 mode_kernel) {
505 if (write) { write_acv++; } else { read_acv++; }
506 uint64_t flags = ((write ? MM_STAT_WR_MASK : 0) |
507 MM_STAT_ACV_MASK);
508 return new DtbAcvFault(req->getVaddr(), req->getFlags(), flags);
509 }
510
511 req->setPaddr(req->getVaddr() & PAddrImplMask);
512
513#if !ALPHA_TLASER
514 // sign extend the physical address properly
515 if (req->getPaddr() & PAddrUncachedBit40)
516 req->setPaddr(req->getPaddr() | ULL(0xf0000000000));
517 else
518 req->setPaddr(req->getPaddr() & ULL(0xffffffffff));
519#endif
520
521 } else {
522 if (write)
523 write_accesses++;
524 else
525 read_accesses++;
526
527 int asn = DTB_ASN_ASN(tc->readMiscRegNoEffect(IPR_DTB_ASN));
528
529 // not a physical address: need to look up pte
530 PTE *pte = lookup(VAddr(req->getVaddr()).vpn(),
531 asn);
532
533 if (!pte) {
534 // page fault
535 if (write) { write_misses++; } else { read_misses++; }
536 uint64_t flags = (write ? MM_STAT_WR_MASK : 0) |
537 MM_STAT_DTB_MISS_MASK;
538 return (req->getFlags() & VPTE) ?
539 (Fault)(new PDtbMissFault(req->getVaddr(), req->getFlags(),
540 flags)) :
541 (Fault)(new NDtbMissFault(req->getVaddr(), req->getFlags(),
542 flags));
543 }
544
545 req->setPaddr((pte->ppn << PageShift) +
546 VAddr(req->getVaddr()).offset());
547
548 if (write) {
549 if (!(pte->xwe & MODE2MASK(mode))) {
550 // declare the instruction access fault
551 write_acv++;
552 uint64_t flags = MM_STAT_WR_MASK |
553 MM_STAT_ACV_MASK |
554 (pte->fonw ? MM_STAT_FONW_MASK : 0);
555 return new DtbPageFault(req->getVaddr(), req->getFlags(), flags);
556 }
557 if (pte->fonw) {
558 write_acv++;
559 uint64_t flags = MM_STAT_WR_MASK |
560 MM_STAT_FONW_MASK;
561 return new DtbPageFault(req->getVaddr(), req->getFlags(), flags);
562 }
563 } else {
564 if (!(pte->xre & MODE2MASK(mode))) {
565 read_acv++;
566 uint64_t flags = MM_STAT_ACV_MASK |
567 (pte->fonr ? MM_STAT_FONR_MASK : 0);
568 return new DtbAcvFault(req->getVaddr(), req->getFlags(), flags);
569 }
570 if (pte->fonr) {
571 read_acv++;
572 uint64_t flags = MM_STAT_FONR_MASK;
573 return new DtbPageFault(req->getVaddr(), req->getFlags(), flags);
574 }
575 }
576 }
577
578 if (write)
579 write_hits++;
580 else
581 read_hits++;
582 }
583
584 // check that the physical address is ok (catch bad physical addresses)
585 if (req->getPaddr() & ~PAddrImplMask)
586 return genMachineCheckFault();
587
588 return checkCacheability(req);
589}
590
591PTE &
592TLB::index(bool advance)
593{
594 PTE *pte = &table[nlu];
595
596 if (advance)
597 nextnlu();
598
599 return *pte;
600}
601
602/* end namespace AlphaISA */ }
603
|