tlb.cc revision 4957:f858d0b8ef99
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" 44#include "params/AlphaDTB.hh" 45#include "params/AlphaITB.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 flushCache(); 68} 69 70TLB::~TLB() 71{ 72 if (table) 73 delete [] table; 74} 75 76// look up an entry in the TLB 77PTE * 78TLB::lookup(Addr vpn, uint8_t asn) const 79{ 80 // assume not found... 81 PTE *retval = NULL; 82 83 if (PTECache[0] && vpn == PTECache[0]->tag && 84 (PTECache[0]->asma || PTECache[0]->asn == asn)) 85 retval = PTECache[0]; 86 else if (PTECache[1] && vpn == PTECache[1]->tag && 87 (PTECache[1]->asma || PTECache[1]->asn == asn)) 88 retval = PTECache[1]; 89 else if (PTECache[2] && vpn == PTECache[2]->tag && 90 (PTECache[2]->asma || PTECache[2]->asn == asn)) 91 retval = PTECache[2]; 92 else { 93 PageTable::const_iterator i = lookupTable.find(vpn); 94 if (i != lookupTable.end()) { 95 while (i->first == vpn) { 96 int index = i->second; 97 PTE *pte = &table[index]; 98 assert(pte->valid); 99 if (vpn == pte->tag && (pte->asma || pte->asn == asn)) { 100 retval = pte; 101 break; 102 } 103 104 ++i; 105 } 106 } 107 } 108 109 DPRINTF(TLB, "lookup %#x, asn %#x -> %s ppn %#x\n", vpn, (int)asn, 110 retval ? "hit" : "miss", retval ? retval->ppn : 0); 111 return retval; 112} 113 114 115Fault 116TLB::checkCacheability(RequestPtr &req) 117{ 118// in Alpha, cacheability is controlled by upper-level bits of the 119// physical address 120 121/* 122 * We support having the uncacheable bit in either bit 39 or bit 40. 123 * The Turbolaser platform (and EV5) support having the bit in 39, but 124 * Tsunami (which Linux assumes uses an EV6) generates accesses with 125 * the bit in 40. So we must check for both, but we have debug flags 126 * to catch a weird case where both are used, which shouldn't happen. 127 */ 128 129 130#if ALPHA_TLASER 131 if (req->getPaddr() & PAddrUncachedBit39) 132#else 133 if (req->getPaddr() & PAddrUncachedBit43) 134#endif 135 { 136 // IPR memory space not implemented 137 if (PAddrIprSpace(req->getPaddr())) { 138 return new UnimpFault("IPR memory space not implemented!"); 139 } else { 140 // mark request as uncacheable 141 req->setFlags(req->getFlags() | UNCACHEABLE); 142 143#if !ALPHA_TLASER 144 // Clear bits 42:35 of the physical address (10-2 in Tsunami manual) 145 req->setPaddr(req->getPaddr() & PAddrUncachedMask); 146#endif 147 } 148 } 149 return NoFault; 150} 151 152 153// insert a new TLB entry 154void 155TLB::insert(Addr addr, PTE &pte) 156{ 157 flushCache(); 158 VAddr vaddr = addr; 159 if (table[nlu].valid) { 160 Addr oldvpn = table[nlu].tag; 161 PageTable::iterator i = lookupTable.find(oldvpn); 162 163 if (i == lookupTable.end()) 164 panic("TLB entry not found in lookupTable"); 165 166 int index; 167 while ((index = i->second) != nlu) { 168 if (table[index].tag != oldvpn) 169 panic("TLB entry not found in lookupTable"); 170 171 ++i; 172 } 173 174 DPRINTF(TLB, "remove @%d: %#x -> %#x\n", nlu, oldvpn, table[nlu].ppn); 175 176 lookupTable.erase(i); 177 } 178 179 DPRINTF(TLB, "insert @%d: %#x -> %#x\n", nlu, vaddr.vpn(), pte.ppn); 180 181 table[nlu] = pte; 182 table[nlu].tag = vaddr.vpn(); 183 table[nlu].valid = true; 184 185 lookupTable.insert(make_pair(vaddr.vpn(), nlu)); 186 nextnlu(); 187} 188 189void 190TLB::flushAll() 191{ 192 DPRINTF(TLB, "flushAll\n"); 193 memset(table, 0, sizeof(PTE[size])); 194 flushCache(); 195 lookupTable.clear(); 196 nlu = 0; 197} 198 199void 200TLB::flushProcesses() 201{ 202 flushCache(); 203 PageTable::iterator i = lookupTable.begin(); 204 PageTable::iterator end = lookupTable.end(); 205 while (i != end) { 206 int index = i->second; 207 PTE *pte = &table[index]; 208 assert(pte->valid); 209 210 // we can't increment i after we erase it, so save a copy and 211 // increment it to get the next entry now 212 PageTable::iterator cur = i; 213 ++i; 214 215 if (!pte->asma) { 216 DPRINTF(TLB, "flush @%d: %#x -> %#x\n", index, pte->tag, pte->ppn); 217 pte->valid = false; 218 lookupTable.erase(cur); 219 } 220 } 221} 222 223void 224TLB::flushAddr(Addr addr, uint8_t asn) 225{ 226 flushCache(); 227 VAddr vaddr = addr; 228 229 PageTable::iterator i = lookupTable.find(vaddr.vpn()); 230 if (i == lookupTable.end()) 231 return; 232 233 while (i != lookupTable.end() && i->first == vaddr.vpn()) { 234 int index = i->second; 235 PTE *pte = &table[index]; 236 assert(pte->valid); 237 238 if (vaddr.vpn() == pte->tag && (pte->asma || pte->asn == asn)) { 239 DPRINTF(TLB, "flushaddr @%d: %#x -> %#x\n", index, vaddr.vpn(), 240 pte->ppn); 241 242 // invalidate this entry 243 pte->valid = false; 244 245 lookupTable.erase(i++); 246 } else { 247 ++i; 248 } 249 } 250} 251 252 253void 254TLB::serialize(ostream &os) 255{ 256 SERIALIZE_SCALAR(size); 257 SERIALIZE_SCALAR(nlu); 258 259 for (int i = 0; i < size; i++) { 260 nameOut(os, csprintf("%s.PTE%d", name(), i)); 261 table[i].serialize(os); 262 } 263} 264 265void 266TLB::unserialize(Checkpoint *cp, const string §ion) 267{ 268 UNSERIALIZE_SCALAR(size); 269 UNSERIALIZE_SCALAR(nlu); 270 271 for (int i = 0; i < size; i++) { 272 table[i].unserialize(cp, csprintf("%s.PTE%d", section, i)); 273 if (table[i].valid) { 274 lookupTable.insert(make_pair(table[i].tag, i)); 275 } 276 } 277} 278 279 280/////////////////////////////////////////////////////////////////////// 281// 282// Alpha ITB 283// 284ITB::ITB(const std::string &name, int size) 285 : TLB(name, size) 286{} 287 288 289void 290ITB::regStats() 291{ 292 hits 293 .name(name() + ".hits") 294 .desc("ITB hits"); 295 misses 296 .name(name() + ".misses") 297 .desc("ITB misses"); 298 acv 299 .name(name() + ".acv") 300 .desc("ITB acv"); 301 accesses 302 .name(name() + ".accesses") 303 .desc("ITB accesses"); 304 305 accesses = hits + misses; 306} 307 308 309Fault 310ITB::translate(RequestPtr &req, ThreadContext *tc) const 311{ 312 //If this is a pal pc, then set PHYSICAL 313 if(FULL_SYSTEM && PcPAL(req->getPC())) 314 req->setFlags(req->getFlags() | PHYSICAL); 315 316 if (PcPAL(req->getPC())) { 317 // strip off PAL PC marker (lsb is 1) 318 req->setPaddr((req->getVaddr() & ~3) & PAddrImplMask); 319 hits++; 320 return NoFault; 321 } 322 323 if (req->getFlags() & PHYSICAL) { 324 req->setPaddr(req->getVaddr()); 325 } else { 326 // verify that this is a good virtual address 327 if (!validVirtualAddress(req->getVaddr())) { 328 acv++; 329 return new ItbAcvFault(req->getVaddr()); 330 } 331 332 333 // VA<42:41> == 2, VA<39:13> maps directly to PA<39:13> for EV5 334 // VA<47:41> == 0x7e, VA<40:13> maps directly to PA<40:13> for EV6 335#if ALPHA_TLASER 336 if ((MCSR_SP(tc->readMiscRegNoEffect(IPR_MCSR)) & 2) && 337 VAddrSpaceEV5(req->getVaddr()) == 2) 338#else 339 if (VAddrSpaceEV6(req->getVaddr()) == 0x7e) 340#endif 341 { 342 // only valid in kernel mode 343 if (ICM_CM(tc->readMiscRegNoEffect(IPR_ICM)) != 344 mode_kernel) { 345 acv++; 346 return new ItbAcvFault(req->getVaddr()); 347 } 348 349 req->setPaddr(req->getVaddr() & PAddrImplMask); 350 351#if !ALPHA_TLASER 352 // sign extend the physical address properly 353 if (req->getPaddr() & PAddrUncachedBit40) 354 req->setPaddr(req->getPaddr() | ULL(0xf0000000000)); 355 else 356 req->setPaddr(req->getPaddr() & ULL(0xffffffffff)); 357#endif 358 359 } else { 360 // not a physical address: need to look up pte 361 int asn = DTB_ASN_ASN(tc->readMiscRegNoEffect(IPR_DTB_ASN)); 362 PTE *pte = lookup(VAddr(req->getVaddr()).vpn(), 363 asn); 364 365 if (!pte) { 366 misses++; 367 return new ItbPageFault(req->getVaddr()); 368 } 369 370 req->setPaddr((pte->ppn << PageShift) + 371 (VAddr(req->getVaddr()).offset() 372 & ~3)); 373 374 // check permissions for this access 375 if (!(pte->xre & 376 (1 << ICM_CM(tc->readMiscRegNoEffect(IPR_ICM))))) { 377 // instruction access fault 378 acv++; 379 return new ItbAcvFault(req->getVaddr()); 380 } 381 382 hits++; 383 } 384 } 385 386 // check that the physical address is ok (catch bad physical addresses) 387 if (req->getPaddr() & ~PAddrImplMask) 388 return genMachineCheckFault(); 389 390 return checkCacheability(req); 391 392} 393 394/////////////////////////////////////////////////////////////////////// 395// 396// Alpha DTB 397// 398 DTB::DTB(const std::string &name, int size) 399 : TLB(name, size) 400{} 401 402void 403DTB::regStats() 404{ 405 read_hits 406 .name(name() + ".read_hits") 407 .desc("DTB read hits") 408 ; 409 410 read_misses 411 .name(name() + ".read_misses") 412 .desc("DTB read misses") 413 ; 414 415 read_acv 416 .name(name() + ".read_acv") 417 .desc("DTB read access violations") 418 ; 419 420 read_accesses 421 .name(name() + ".read_accesses") 422 .desc("DTB read accesses") 423 ; 424 425 write_hits 426 .name(name() + ".write_hits") 427 .desc("DTB write hits") 428 ; 429 430 write_misses 431 .name(name() + ".write_misses") 432 .desc("DTB write misses") 433 ; 434 435 write_acv 436 .name(name() + ".write_acv") 437 .desc("DTB write access violations") 438 ; 439 440 write_accesses 441 .name(name() + ".write_accesses") 442 .desc("DTB write accesses") 443 ; 444 445 hits 446 .name(name() + ".hits") 447 .desc("DTB hits") 448 ; 449 450 misses 451 .name(name() + ".misses") 452 .desc("DTB misses") 453 ; 454 455 acv 456 .name(name() + ".acv") 457 .desc("DTB access violations") 458 ; 459 460 accesses 461 .name(name() + ".accesses") 462 .desc("DTB accesses") 463 ; 464 465 hits = read_hits + write_hits; 466 misses = read_misses + write_misses; 467 acv = read_acv + write_acv; 468 accesses = read_accesses + write_accesses; 469} 470 471Fault 472DTB::translate(RequestPtr &req, ThreadContext *tc, bool write) const 473{ 474 Addr pc = tc->readPC(); 475 476 mode_type mode = 477 (mode_type)DTB_CM_CM(tc->readMiscRegNoEffect(IPR_DTB_CM)); 478 479 480 /** 481 * Check for alignment faults 482 */ 483 if (req->getVaddr() & (req->getSize() - 1)) { 484 DPRINTF(TLB, "Alignment Fault on %#x, size = %d", req->getVaddr(), 485 req->getSize()); 486 uint64_t flags = write ? MM_STAT_WR_MASK : 0; 487 return new DtbAlignmentFault(req->getVaddr(), req->getFlags(), flags); 488 } 489 490 if (PcPAL(pc)) { 491 mode = (req->getFlags() & ALTMODE) ? 492 (mode_type)ALT_MODE_AM( 493 tc->readMiscRegNoEffect(IPR_ALT_MODE)) 494 : mode_kernel; 495 } 496 497 if (req->getFlags() & PHYSICAL) { 498 req->setPaddr(req->getVaddr()); 499 } else { 500 // verify that this is a good virtual address 501 if (!validVirtualAddress(req->getVaddr())) { 502 if (write) { write_acv++; } else { read_acv++; } 503 uint64_t flags = (write ? MM_STAT_WR_MASK : 0) | 504 MM_STAT_BAD_VA_MASK | 505 MM_STAT_ACV_MASK; 506 return new DtbPageFault(req->getVaddr(), req->getFlags(), flags); 507 } 508 509 // Check for "superpage" mapping 510#if ALPHA_TLASER 511 if ((MCSR_SP(tc->readMiscRegNoEffect(IPR_MCSR)) & 2) && 512 VAddrSpaceEV5(req->getVaddr()) == 2) 513#else 514 if (VAddrSpaceEV6(req->getVaddr()) == 0x7e) 515#endif 516 { 517 518 // only valid in kernel mode 519 if (DTB_CM_CM(tc->readMiscRegNoEffect(IPR_DTB_CM)) != 520 mode_kernel) { 521 if (write) { write_acv++; } else { read_acv++; } 522 uint64_t flags = ((write ? MM_STAT_WR_MASK : 0) | 523 MM_STAT_ACV_MASK); 524 return new DtbAcvFault(req->getVaddr(), req->getFlags(), flags); 525 } 526 527 req->setPaddr(req->getVaddr() & PAddrImplMask); 528 529#if !ALPHA_TLASER 530 // sign extend the physical address properly 531 if (req->getPaddr() & PAddrUncachedBit40) 532 req->setPaddr(req->getPaddr() | ULL(0xf0000000000)); 533 else 534 req->setPaddr(req->getPaddr() & ULL(0xffffffffff)); 535#endif 536 537 } else { 538 if (write) 539 write_accesses++; 540 else 541 read_accesses++; 542 543 int asn = DTB_ASN_ASN(tc->readMiscRegNoEffect(IPR_DTB_ASN)); 544 545 // not a physical address: need to look up pte 546 PTE *pte = lookup(VAddr(req->getVaddr()).vpn(), 547 asn); 548 549 if (!pte) { 550 // page fault 551 if (write) { write_misses++; } else { read_misses++; } 552 uint64_t flags = (write ? MM_STAT_WR_MASK : 0) | 553 MM_STAT_DTB_MISS_MASK; 554 return (req->getFlags() & VPTE) ? 555 (Fault)(new PDtbMissFault(req->getVaddr(), req->getFlags(), 556 flags)) : 557 (Fault)(new NDtbMissFault(req->getVaddr(), req->getFlags(), 558 flags)); 559 } 560 561 req->setPaddr((pte->ppn << PageShift) + 562 VAddr(req->getVaddr()).offset()); 563 564 if (write) { 565 if (!(pte->xwe & MODE2MASK(mode))) { 566 // declare the instruction access fault 567 write_acv++; 568 uint64_t flags = MM_STAT_WR_MASK | 569 MM_STAT_ACV_MASK | 570 (pte->fonw ? MM_STAT_FONW_MASK : 0); 571 return new DtbPageFault(req->getVaddr(), req->getFlags(), flags); 572 } 573 if (pte->fonw) { 574 write_acv++; 575 uint64_t flags = MM_STAT_WR_MASK | 576 MM_STAT_FONW_MASK; 577 return new DtbPageFault(req->getVaddr(), req->getFlags(), flags); 578 } 579 } else { 580 if (!(pte->xre & MODE2MASK(mode))) { 581 read_acv++; 582 uint64_t flags = MM_STAT_ACV_MASK | 583 (pte->fonr ? MM_STAT_FONR_MASK : 0); 584 return new DtbAcvFault(req->getVaddr(), req->getFlags(), flags); 585 } 586 if (pte->fonr) { 587 read_acv++; 588 uint64_t flags = MM_STAT_FONR_MASK; 589 return new DtbPageFault(req->getVaddr(), req->getFlags(), flags); 590 } 591 } 592 } 593 594 if (write) 595 write_hits++; 596 else 597 read_hits++; 598 } 599 600 // check that the physical address is ok (catch bad physical addresses) 601 if (req->getPaddr() & ~PAddrImplMask) 602 return genMachineCheckFault(); 603 604 return checkCacheability(req); 605} 606 607PTE & 608TLB::index(bool advance) 609{ 610 PTE *pte = &table[nlu]; 611 612 if (advance) 613 nextnlu(); 614 615 return *pte; 616} 617 618/* end namespace AlphaISA */ } 619 620AlphaISA::ITB * 621AlphaITBParams::create() 622{ 623 return new AlphaISA::ITB(name, size); 624} 625 626AlphaISA::DTB * 627AlphaDTBParams::create() 628{ 629 return new AlphaISA::DTB(name, size); 630} 631