table_walker.cc revision 7582
1/* 2 * Copyright (c) 2010 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 * Redistribution and use in source and binary forms, with or without 15 * modification, are permitted provided that the following conditions are 16 * met: redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer; 18 * redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution; 21 * neither the name of the copyright holders nor the names of its 22 * contributors may be used to endorse or promote products derived from 23 * this software without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 26 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 27 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 28 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 29 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 30 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 31 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 32 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 35 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 36 * 37 * Authors: Ali Saidi 38 */ 39 40#include "arch/arm/faults.hh" 41#include "arch/arm/table_walker.hh" 42#include "arch/arm/tlb.hh" 43#include "dev/io_device.hh" 44#include "cpu/thread_context.hh" 45 46using namespace ArmISA; 47 48TableWalker::TableWalker(const Params *p) 49 : MemObject(p), port(NULL), tlb(NULL), 50 currState(NULL), doL1DescEvent(this), doL2DescEvent(this) 51{ 52 sctlr = 0; 53} 54 55TableWalker::~TableWalker() 56{ 57 ; 58} 59 60 61unsigned int 62drain(Event *de) 63{ 64 panic("Not implemented\n"); 65} 66 67Port* 68TableWalker::getPort(const std::string &if_name, int idx) 69{ 70 if (if_name == "port") { 71 if (port != NULL) 72 fatal("%s: port already connected to %s", 73 name(), port->getPeer()->name()); 74 System *sys = params()->sys; 75 Tick minb = params()->min_backoff; 76 Tick maxb = params()->max_backoff; 77 port = new DmaPort(this, sys, minb, maxb); 78 return port; 79 } 80 return NULL; 81} 82 83Fault 84TableWalker::walk(RequestPtr _req, ThreadContext *_tc, uint8_t _cid, TLB::Mode _mode, 85 TLB::Translation *_trans, bool _timing) 86{ 87 if (!currState) { 88 // For atomic mode, a new WalkerState instance should be only created 89 // once per TLB. For timing mode, a new instance is generated for every 90 // TLB miss. 91 DPRINTF(TLBVerbose, "creating new instance of WalkerState\n"); 92 93 currState = new WalkerState(); 94 currState->tableWalker = this; 95 } 96 else if (_timing) { 97 panic("currState should always be empty in timing mode!\n"); 98 } 99 100 currState->tc = _tc; 101 currState->transState = _trans; 102 currState->req = _req; 103 currState->fault = NoFault; 104 currState->contextId = _cid; 105 currState->timing = _timing; 106 currState->mode = _mode; 107 108 /** @todo These should be cached or grabbed from cached copies in 109 the TLB, all these miscreg reads are expensive */ 110 currState->vaddr = currState->req->getVaddr() & ~PcModeMask; 111 currState->sctlr = currState->tc->readMiscReg(MISCREG_SCTLR); 112 sctlr = currState->sctlr; 113 currState->cpsr = currState->tc->readMiscReg(MISCREG_CPSR); 114 currState->N = currState->tc->readMiscReg(MISCREG_TTBCR); 115 116 currState->isFetch = (currState->mode == TLB::Execute); 117 currState->isWrite = (currState->mode == TLB::Write); 118 currState->isPriv = (currState->cpsr.mode != MODE_USER); 119 120 Addr ttbr = 0; 121 122 // If translation isn't enabled, we shouldn't be here 123 assert(currState->sctlr.m); 124 125 DPRINTF(TLB, "Begining table walk for address %#x, TTBCR: %#x, bits:%#x\n", 126 currState->vaddr, currState->N, mbits(currState->vaddr, 31, 127 32-currState->N)); 128 129 if (currState->N == 0 || !mbits(currState->vaddr, 31, 32-currState->N)) { 130 DPRINTF(TLB, " - Selecting TTBR0\n"); 131 ttbr = currState->tc->readMiscReg(MISCREG_TTBR0); 132 } else { 133 DPRINTF(TLB, " - Selecting TTBR1\n"); 134 ttbr = currState->tc->readMiscReg(MISCREG_TTBR1); 135 currState->N = 0; 136 } 137 138 Addr l1desc_addr = mbits(ttbr, 31, 14-currState->N) | 139 (bits(currState->vaddr,31-currState->N,20) << 2); 140 DPRINTF(TLB, " - Descriptor at address %#x\n", l1desc_addr); 141 142 143 // Trickbox address check 144 Fault f; 145 f = tlb->walkTrickBoxCheck(l1desc_addr, currState->vaddr, sizeof(uint32_t), 146 currState->isFetch, currState->isWrite, 0, true); 147 if (f) { 148 if (currState->timing) { 149 currState->transState->finish(f, currState->req, 150 currState->tc, currState->mode); 151 currState = NULL; 152 } else { 153 currState->tc = NULL; 154 currState->req = NULL; 155 } 156 return f; 157 } 158 159 if (currState->timing) { 160 port->dmaAction(MemCmd::ReadReq, l1desc_addr, sizeof(uint32_t), 161 &doL1DescEvent, (uint8_t*)&currState->l1Desc.data, (Tick)0); 162 DPRINTF(TLBVerbose, "Adding to walker fifo: queue size before adding: %d\n", 163 stateQueue.size()); 164 stateQueue.push_back(currState); 165 assert(stateQueue.size() < 5); 166 currState = NULL; 167 } else { 168 port->dmaAction(MemCmd::ReadReq, l1desc_addr, sizeof(uint32_t), 169 NULL, (uint8_t*)&currState->l1Desc.data, (Tick)0); 170 doL1Descriptor(); 171 f = currState->fault; 172 } 173 174 return f; 175} 176 177void 178TableWalker::memAttrs(ThreadContext *tc, TlbEntry &te, SCTLR sctlr, 179 uint8_t texcb, bool s) 180{ 181 // Note: tc and sctlr local variables are hiding tc and sctrl class 182 // variables 183 DPRINTF(TLBVerbose, "memAttrs texcb:%d s:%d\n", texcb, s); 184 te.shareable = false; // default value 185 te.nonCacheable = false; 186 bool outer_shareable = false; 187 if (sctlr.tre == 0 || ((sctlr.tre == 1) && (sctlr.m == 0))) { 188 switch(texcb) { 189 case 0: // Stongly-ordered 190 te.nonCacheable = true; 191 te.mtype = TlbEntry::StronglyOrdered; 192 te.shareable = true; 193 te.innerAttrs = 1; 194 te.outerAttrs = 0; 195 break; 196 case 1: // Shareable Device 197 te.nonCacheable = true; 198 te.mtype = TlbEntry::Device; 199 te.shareable = true; 200 te.innerAttrs = 3; 201 te.outerAttrs = 0; 202 break; 203 case 2: // Outer and Inner Write-Through, no Write-Allocate 204 te.mtype = TlbEntry::Normal; 205 te.shareable = s; 206 te.innerAttrs = 6; 207 te.outerAttrs = bits(texcb, 1, 0); 208 break; 209 case 3: // Outer and Inner Write-Back, no Write-Allocate 210 te.mtype = TlbEntry::Normal; 211 te.shareable = s; 212 te.innerAttrs = 7; 213 te.outerAttrs = bits(texcb, 1, 0); 214 break; 215 case 4: // Outer and Inner Non-cacheable 216 te.nonCacheable = true; 217 te.mtype = TlbEntry::Normal; 218 te.shareable = s; 219 te.innerAttrs = 0; 220 te.outerAttrs = bits(texcb, 1, 0); 221 break; 222 case 5: // Reserved 223 panic("Reserved texcb value!\n"); 224 break; 225 case 6: // Implementation Defined 226 panic("Implementation-defined texcb value!\n"); 227 break; 228 case 7: // Outer and Inner Write-Back, Write-Allocate 229 te.mtype = TlbEntry::Normal; 230 te.shareable = s; 231 te.innerAttrs = 5; 232 te.outerAttrs = 1; 233 break; 234 case 8: // Non-shareable Device 235 te.nonCacheable = true; 236 te.mtype = TlbEntry::Device; 237 te.shareable = false; 238 te.innerAttrs = 3; 239 te.outerAttrs = 0; 240 break; 241 case 9 ... 15: // Reserved 242 panic("Reserved texcb value!\n"); 243 break; 244 case 16 ... 31: // Cacheable Memory 245 te.mtype = TlbEntry::Normal; 246 te.shareable = s; 247 if (bits(texcb, 1,0) == 0 || bits(texcb, 3,2) == 0) 248 te.nonCacheable = true; 249 te.innerAttrs = bits(texcb, 1, 0); 250 te.outerAttrs = bits(texcb, 3, 2); 251 break; 252 default: 253 panic("More than 32 states for 5 bits?\n"); 254 } 255 } else { 256 assert(tc); 257 PRRR prrr = tc->readMiscReg(MISCREG_PRRR); 258 NMRR nmrr = tc->readMiscReg(MISCREG_NMRR); 259 DPRINTF(TLBVerbose, "memAttrs PRRR:%08x NMRR:%08x\n", prrr, nmrr); 260 uint8_t curr_tr = 0, curr_ir = 0, curr_or = 0; 261 switch(bits(texcb, 2,0)) { 262 case 0: 263 curr_tr = prrr.tr0; 264 curr_ir = nmrr.ir0; 265 curr_or = nmrr.or0; 266 outer_shareable = (prrr.nos0 == 0); 267 break; 268 case 1: 269 curr_tr = prrr.tr1; 270 curr_ir = nmrr.ir1; 271 curr_or = nmrr.or1; 272 outer_shareable = (prrr.nos1 == 0); 273 break; 274 case 2: 275 curr_tr = prrr.tr2; 276 curr_ir = nmrr.ir2; 277 curr_or = nmrr.or2; 278 outer_shareable = (prrr.nos2 == 0); 279 break; 280 case 3: 281 curr_tr = prrr.tr3; 282 curr_ir = nmrr.ir3; 283 curr_or = nmrr.or3; 284 outer_shareable = (prrr.nos3 == 0); 285 break; 286 case 4: 287 curr_tr = prrr.tr4; 288 curr_ir = nmrr.ir4; 289 curr_or = nmrr.or4; 290 outer_shareable = (prrr.nos4 == 0); 291 break; 292 case 5: 293 curr_tr = prrr.tr5; 294 curr_ir = nmrr.ir5; 295 curr_or = nmrr.or5; 296 outer_shareable = (prrr.nos5 == 0); 297 break; 298 case 6: 299 panic("Imp defined type\n"); 300 case 7: 301 curr_tr = prrr.tr7; 302 curr_ir = nmrr.ir7; 303 curr_or = nmrr.or7; 304 outer_shareable = (prrr.nos7 == 0); 305 break; 306 } 307 308 switch(curr_tr) { 309 case 0: 310 DPRINTF(TLBVerbose, "StronglyOrdered\n"); 311 te.mtype = TlbEntry::StronglyOrdered; 312 te.nonCacheable = true; 313 te.innerAttrs = 1; 314 te.outerAttrs = 0; 315 te.shareable = true; 316 break; 317 case 1: 318 DPRINTF(TLBVerbose, "Device ds1:%d ds0:%d s:%d\n", 319 prrr.ds1, prrr.ds0, s); 320 te.mtype = TlbEntry::Device; 321 te.nonCacheable = true; 322 te.innerAttrs = 3; 323 te.outerAttrs = 0; 324 if (prrr.ds1 && s) 325 te.shareable = true; 326 if (prrr.ds0 && !s) 327 te.shareable = true; 328 break; 329 case 2: 330 DPRINTF(TLBVerbose, "Normal ns1:%d ns0:%d s:%d\n", 331 prrr.ns1, prrr.ns0, s); 332 te.mtype = TlbEntry::Normal; 333 if (prrr.ns1 && s) 334 te.shareable = true; 335 if (prrr.ns0 && !s) 336 te.shareable = true; 337 break; 338 case 3: 339 panic("Reserved type"); 340 } 341 342 if (te.mtype == TlbEntry::Normal){ 343 switch(curr_ir) { 344 case 0: 345 te.nonCacheable = true; 346 te.innerAttrs = 0; 347 break; 348 case 1: 349 te.innerAttrs = 5; 350 break; 351 case 2: 352 te.innerAttrs = 6; 353 break; 354 case 3: 355 te.innerAttrs = 7; 356 break; 357 } 358 359 switch(curr_or) { 360 case 0: 361 te.nonCacheable = true; 362 te.outerAttrs = 0; 363 break; 364 case 1: 365 te.outerAttrs = 1; 366 break; 367 case 2: 368 te.outerAttrs = 2; 369 break; 370 case 3: 371 te.outerAttrs = 3; 372 break; 373 } 374 } 375 } 376 DPRINTF(TLBVerbose, "memAttrs: shareable: %d, innerAttrs: %d, \ 377 outerAttrs: %d\n", 378 te.shareable, te.innerAttrs, te.outerAttrs); 379 380 /** Formatting for Physical Address Register (PAR) 381 * Only including lower bits (TLB info here) 382 * PAR: 383 * PA [31:12] 384 * Reserved [11] 385 * TLB info [10:1] 386 * NOS [10] (Not Outer Sharable) 387 * NS [9] (Non-Secure) 388 * -- [8] (Implementation Defined) 389 * SH [7] (Sharable) 390 * Inner[6:4](Inner memory attributes) 391 * Outer[3:2](Outer memory attributes) 392 * SS [1] (SuperSection) 393 * F [0] (Fault, Fault Status in [6:1] if faulted) 394 */ 395 te.attributes = ( 396 ((outer_shareable ? 0:1) << 10) | 397 // TODO: NS Bit 398 ((te.shareable ? 1:0) << 7) | 399 (te.innerAttrs << 4) | 400 (te.outerAttrs << 2) 401 // TODO: Supersection bit 402 // TODO: Fault bit 403 ); 404 405 406} 407 408void 409TableWalker::doL1Descriptor() 410{ 411 DPRINTF(TLB, "L1 descriptor for %#x is %#x\n", 412 currState->vaddr, currState->l1Desc.data); 413 TlbEntry te; 414 415 switch (currState->l1Desc.type()) { 416 case L1Descriptor::Ignore: 417 case L1Descriptor::Reserved: 418 if (!currState->delayed) { 419 currState->tc = NULL; 420 currState->req = NULL; 421 } 422 DPRINTF(TLB, "L1 Descriptor Reserved/Ignore, causing fault\n"); 423 if (currState->isFetch) 424 currState->fault = 425 new PrefetchAbort(currState->vaddr, ArmFault::Translation0); 426 else 427 currState->fault = 428 new DataAbort(currState->vaddr, 0, currState->isWrite, 429 ArmFault::Translation0); 430 return; 431 case L1Descriptor::Section: 432 if (currState->sctlr.afe && bits(currState->l1Desc.ap(), 0) == 0) { 433 /** @todo: check sctlr.ha (bit[17]) if Hardware Access Flag is 434 * enabled if set, do l1.Desc.setAp0() instead of generating 435 * AccessFlag0 436 */ 437 438 currState->fault = 439 new DataAbort(currState->vaddr, NULL, currState->isWrite, 440 ArmFault::AccessFlag0); 441 } 442 443 if (currState->l1Desc.supersection()) { 444 panic("Haven't implemented supersections\n"); 445 } 446 te.N = 20; 447 te.pfn = currState->l1Desc.pfn(); 448 te.size = (1<<te.N) - 1; 449 te.global = !currState->l1Desc.global(); 450 te.valid = true; 451 te.vpn = currState->vaddr >> te.N; 452 te.sNp = true; 453 te.xn = currState->l1Desc.xn(); 454 te.ap = currState->l1Desc.ap(); 455 te.domain = currState->l1Desc.domain(); 456 te.asid = currState->contextId; 457 memAttrs(currState->tc, te, currState->sctlr, 458 currState->l1Desc.texcb(), currState->l1Desc.shareable()); 459 460 DPRINTF(TLB, "Inserting Section Descriptor into TLB\n"); 461 DPRINTF(TLB, " - N:%d pfn:%#x size: %#x global:%d valid: %d\n", 462 te.N, te.pfn, te.size, te.global, te.valid); 463 DPRINTF(TLB, " - vpn:%#x sNp: %d xn:%d ap:%d domain: %d asid:%d nc:%d\n", 464 te.vpn, te.sNp, te.xn, te.ap, te.domain, te.asid, 465 te.nonCacheable); 466 DPRINTF(TLB, " - domain from l1 desc: %d data: %#x bits:%d\n", 467 currState->l1Desc.domain(), currState->l1Desc.data, 468 (currState->l1Desc.data >> 5) & 0xF ); 469 470 if (!currState->timing) { 471 currState->tc = NULL; 472 currState->req = NULL; 473 } 474 tlb->insert(currState->vaddr, te); 475 476 return; 477 case L1Descriptor::PageTable: 478 Addr l2desc_addr; 479 l2desc_addr = currState->l1Desc.l2Addr() | 480 (bits(currState->vaddr, 19,12) << 2); 481 DPRINTF(TLB, "L1 descriptor points to page table at: %#x\n", 482 l2desc_addr); 483 484 // Trickbox address check 485 currState->fault = tlb->walkTrickBoxCheck(l2desc_addr, currState->vaddr, 486 sizeof(uint32_t), currState->isFetch, currState->isWrite, 487 currState->l1Desc.domain(), false); 488 489 if (currState->fault) { 490 if (!currState->timing) { 491 currState->tc = NULL; 492 currState->req = NULL; 493 } 494 return; 495 } 496 497 498 if (currState->timing) { 499 currState->delayed = true; 500 port->dmaAction(MemCmd::ReadReq, l2desc_addr, sizeof(uint32_t), 501 &doL2DescEvent, (uint8_t*)&currState->l2Desc.data, 0); 502 } else { 503 port->dmaAction(MemCmd::ReadReq, l2desc_addr, sizeof(uint32_t), 504 NULL, (uint8_t*)&currState->l2Desc.data, 0); 505 doL2Descriptor(); 506 } 507 return; 508 default: 509 panic("A new type in a 2 bit field?\n"); 510 } 511} 512 513void 514TableWalker::doL2Descriptor() 515{ 516 DPRINTF(TLB, "L2 descriptor for %#x is %#x\n", 517 currState->vaddr, currState->l2Desc.data); 518 TlbEntry te; 519 520 if (currState->l2Desc.invalid()) { 521 DPRINTF(TLB, "L2 descriptor invalid, causing fault\n"); 522 if (!currState->delayed) { 523 currState->tc = NULL; 524 currState->req = NULL; 525 } 526 if (currState->isFetch) 527 currState->fault = 528 new PrefetchAbort(currState->vaddr, ArmFault::Translation1); 529 else 530 currState->fault = 531 new DataAbort(currState->vaddr, currState->l1Desc.domain(), 532 currState->isWrite, ArmFault::Translation1); 533 return; 534 } 535 536 if (currState->sctlr.afe && bits(currState->l2Desc.ap(), 0) == 0) { 537 /** @todo: check sctlr.ha (bit[17]) if Hardware Access Flag is enabled 538 * if set, do l2.Desc.setAp0() instead of generating AccessFlag0 539 */ 540 541 currState->fault = 542 new DataAbort(currState->vaddr, 0, currState->isWrite, 543 ArmFault::AccessFlag1); 544 545 } 546 547 if (currState->l2Desc.large()) { 548 te.N = 16; 549 te.pfn = currState->l2Desc.pfn(); 550 } else { 551 te.N = 12; 552 te.pfn = currState->l2Desc.pfn(); 553 } 554 555 te.valid = true; 556 te.size = (1 << te.N) - 1; 557 te.asid = currState->contextId; 558 te.sNp = false; 559 te.vpn = currState->vaddr >> te.N; 560 te.global = currState->l2Desc.global(); 561 te.xn = currState->l2Desc.xn(); 562 te.ap = currState->l2Desc.ap(); 563 te.domain = currState->l1Desc.domain(); 564 memAttrs(currState->tc, te, currState->sctlr, currState->l2Desc.texcb(), 565 currState->l2Desc.shareable()); 566 567 if (!currState->delayed) { 568 currState->tc = NULL; 569 currState->req = NULL; 570 } 571 tlb->insert(currState->vaddr, te); 572} 573 574void 575TableWalker::doL1DescriptorWrapper() 576{ 577 currState = stateQueue.front(); 578 currState->delayed = false; 579 580 DPRINTF(TLBVerbose, "L1 Desc object host addr: %p\n",&currState->l1Desc.data); 581 DPRINTF(TLBVerbose, "L1 Desc object data: %08x\n",currState->l1Desc.data); 582 583 DPRINTF(TLBVerbose, "calling doL1Descriptor for vaddr:%#x\n", currState->vaddr); 584 doL1Descriptor(); 585 586 // Check if fault was generated 587 if (currState->fault != NoFault) { 588 currState->transState->finish(currState->fault, currState->req, 589 currState->tc, currState->mode); 590 591 currState->req = NULL; 592 currState->tc = NULL; 593 currState->delayed = false; 594 595 stateQueue.pop_front(); 596 } 597 else if (!currState->delayed) { 598 DPRINTF(TLBVerbose, "calling translateTiming again\n"); 599 currState->fault = tlb->translateTiming(currState->req, currState->tc, 600 currState->transState, currState->mode); 601 602 currState->req = NULL; 603 currState->tc = NULL; 604 currState->delayed = false; 605 606 stateQueue.pop_front(); 607 } 608 currState = NULL; 609} 610 611void 612TableWalker::doL2DescriptorWrapper() 613{ 614 currState = stateQueue.front(); 615 assert(currState->delayed); 616 617 DPRINTF(TLBVerbose, "calling doL2Descriptor for vaddr:%#x\n", 618 currState->vaddr); 619 doL2Descriptor(); 620 621 // Check if fault was generated 622 if (currState->fault != NoFault) { 623 currState->transState->finish(currState->fault, currState->req, 624 currState->tc, currState->mode); 625 } 626 else { 627 DPRINTF(TLBVerbose, "calling translateTiming again\n"); 628 currState->fault = tlb->translateTiming(currState->req, currState->tc, 629 currState->transState, currState->mode); 630 } 631 632 currState->req = NULL; 633 currState->tc = NULL; 634 currState->delayed = false; 635 636 stateQueue.pop_front(); 637 currState = NULL; 638} 639 640ArmISA::TableWalker * 641ArmTableWalkerParams::create() 642{ 643 return new ArmISA::TableWalker(this); 644} 645 646