packet.hh revision 11199:929fd978ab4e
12SN/A/* 21762SN/A * Copyright (c) 2012-2015 ARM Limited 32SN/A * All rights reserved 42SN/A * 52SN/A * The license below extends only to copyright in the software and shall 62SN/A * not be construed as granting a license to any other intellectual 72SN/A * property including but not limited to intellectual property relating 82SN/A * to a hardware implementation of the functionality of the software 92SN/A * licensed hereunder. You may use the software subject to the license 102SN/A * terms below provided that you ensure that this notice is replicated 112SN/A * unmodified and in its entirety in all distributions of the software, 122SN/A * modified or unmodified, in source code or in binary form. 132SN/A * 142SN/A * Copyright (c) 2006 The Regents of The University of Michigan 152SN/A * Copyright (c) 2010,2015 Advanced Micro Devices, Inc. 162SN/A * All rights reserved. 172SN/A * 182SN/A * Redistribution and use in source and binary forms, with or without 192SN/A * modification, are permitted provided that the following conditions are 202SN/A * met: redistributions of source code must retain the above copyright 212SN/A * notice, this list of conditions and the following disclaimer; 222SN/A * redistributions in binary form must reproduce the above copyright 232SN/A * notice, this list of conditions and the following disclaimer in the 242SN/A * documentation and/or other materials provided with the distribution; 252SN/A * neither the name of the copyright holders nor the names of its 262SN/A * contributors may be used to endorse or promote products derived from 272665Ssaidi@eecs.umich.edu * this software without specific prior written permission. 282665Ssaidi@eecs.umich.edu * 292665Ssaidi@eecs.umich.edu * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 302665Ssaidi@eecs.umich.edu * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 312SN/A * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 322SN/A * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 332SN/A * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 342SN/A * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 352SN/A * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 362SN/A * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 3775SN/A * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 382SN/A * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 392439SN/A * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 402439SN/A * 41603SN/A * Authors: Ron Dreslinski 42603SN/A * Steve Reinhardt 432520SN/A * Ali Saidi 442378SN/A * Andreas Hansson 452378SN/A */ 46722SN/A 472521SN/A/** 482378SN/A * @file 49312SN/A * Declaration of the Packet class. 501634SN/A */ 511634SN/A 521634SN/A#ifndef __MEM_PACKET_HH__ 532521SN/A#define __MEM_PACKET_HH__ 542378SN/A 552378SN/A#include <bitset> 56803SN/A#include <cassert> 572378SN/A#include <list> 582SN/A 591070SN/A#include "base/cast.hh" 602378SN/A#include "base/compiler.hh" 612SN/A#include "base/flags.hh" 622SN/A#include "base/misc.hh" 632SN/A#include "base/printable.hh" 64603SN/A#include "base/types.hh" 652521SN/A#include "mem/request.hh" 662SN/A#include "sim/core.hh" 672SN/A 68180SN/Aclass Packet; 691806SN/Atypedef Packet *PacketPtr; 701806SN/Atypedef uint8_t* PacketDataPtr; 711806SN/Atypedef std::list<PacketPtr> PacketList; 721806SN/A 731806SN/Aclass MemCmd 741806SN/A{ 751806SN/A friend class Packet; 761806SN/A 771806SN/A public: 78180SN/A /** 792378SN/A * List of all commands associated with a packet. 802378SN/A */ 812378SN/A enum Command 822378SN/A { 832520SN/A InvalidCmd, 842520SN/A ReadReq, 852520SN/A ReadResp, 862521SN/A ReadRespWithInvalidate, 872520SN/A WriteReq, 881885SN/A WriteResp, 891070SN/A WritebackDirty, 90954SN/A WritebackClean, 911070SN/A CleanEvict, 921070SN/A SoftPFReq, 931070SN/A HardPFReq, 941070SN/A SoftPFResp, 951070SN/A HardPFResp, 961070SN/A WriteLineReq, 971070SN/A UpgradeReq, 981070SN/A SCUpgradeReq, // Special "weak" upgrade for StoreCond 991070SN/A UpgradeResp, 1001070SN/A SCUpgradeFailReq, // Failed SCUpgradeReq in MSHR (never sent) 1011070SN/A UpgradeFailResp, // Valid for SCUpgradeReq only 1021070SN/A ReadExReq, 1031070SN/A ReadExResp, 1041070SN/A ReadCleanReq, 1052378SN/A ReadSharedReq, 1062378SN/A LoadLockedReq, 1072378SN/A StoreCondReq, 1082378SN/A StoreCondFailReq, // Failed StoreCondReq in MSHR (never sent) 1092378SN/A StoreCondResp, 1102378SN/A SwapReq, 1112378SN/A SwapResp, 1121885SN/A MessageReq, 1131885SN/A MessageResp, 1142424SN/A ReleaseReq, 1151885SN/A ReleaseResp, 1161885SN/A AcquireReq, 1171885SN/A AcquireResp, 1181885SN/A // Error responses 1191885SN/A // @TODO these should be classified as responses rather than 1202158SN/A // requests; coding them as requests initially for backwards 1211885SN/A // compatibility 1221885SN/A InvalidDestError, // packet dest field invalid 1231885SN/A BadAddressError, // memory address invalid 1241885SN/A FunctionalReadError, // unable to fulfill functional read 1251885SN/A FunctionalWriteError, // unable to fulfill functional write 1261885SN/A // Fake simulator-only commands 1271885SN/A PrintReq, // Print state matching address 1281885SN/A FlushReq, //request for a cache flush 1291913SN/A InvalidateReq, // request for address to be invalidated 1301885SN/A InvalidateResp, 1311885SN/A NUM_MEM_CMDS 1321885SN/A }; 1331885SN/A 1341885SN/A private: 1351885SN/A /** 1361885SN/A * List of command attributes. 1371885SN/A */ 1381885SN/A enum Attribute 1391885SN/A { 1401885SN/A IsRead, //!< Data flows from responder to requester 1411885SN/A IsWrite, //!< Data flows from requester to responder 1421885SN/A IsUpgrade, 1431885SN/A IsInvalidate, 1441885SN/A NeedsExclusive, //!< Requires exclusive copy to complete in-cache 1451885SN/A IsRequest, //!< Issued by requester 1462378SN/A IsResponse, //!< Issue by responder 14777SN/A NeedsResponse, //!< Requester needs response from target 1482378SN/A IsEviction, 1491070SN/A IsSWPrefetch, 1501070SN/A IsHWPrefetch, 1512158SN/A IsLlsc, //!< Alpha/MIPS LL or SC access 1522378SN/A HasData, //!< There is an associated payload 1531070SN/A IsError, //!< Error response 1541070SN/A IsPrint, //!< Print state matching address (for debugging) 1551070SN/A IsFlush, //!< Flush the address from caches 1561070SN/A NUM_COMMAND_ATTRIBUTES 1571070SN/A }; 1582521SN/A 1592378SN/A /** 1602378SN/A * Structure that defines attributes and other data associated 1611634SN/A * with a Command. 1622567SN/A */ 1631070SN/A struct CommandInfo 1641070SN/A { 1651070SN/A /// Set of attribute flags. 1661082SN/A const std::bitset<NUM_COMMAND_ATTRIBUTES> attributes; 1671070SN/A /// Corresponding response for requests; InvalidCmd if no 1681070SN/A /// response is applicable. 1692158SN/A const Command response; 1702378SN/A /// String representation (for printing) 1712158SN/A const std::string str; 1721070SN/A }; 1732158SN/A 1742158SN/A /// Array to map Command enum to associated info. 1751070SN/A static const CommandInfo commandInfo[]; 1762158SN/A 1771070SN/A private: 1782SN/A 1792SN/A Command cmd; 1801129SN/A 1811129SN/A bool 1822158SN/A testCmdAttrib(MemCmd::Attribute attrib) const 1832158SN/A { 1841070SN/A return commandInfo[cmd].attributes[attrib] != 0; 1852378SN/A } 1862378SN/A 1871070SN/A public: 1881070SN/A 1891070SN/A bool isRead() const { return testCmdAttrib(IsRead); } 1901070SN/A bool isWrite() const { return testCmdAttrib(IsWrite); } 1911070SN/A bool isUpgrade() const { return testCmdAttrib(IsUpgrade); } 1921070SN/A bool isRequest() const { return testCmdAttrib(IsRequest); } 1931070SN/A bool isResponse() const { return testCmdAttrib(IsResponse); } 1941070SN/A bool needsExclusive() const { return testCmdAttrib(NeedsExclusive); } 1951070SN/A bool needsResponse() const { return testCmdAttrib(NeedsResponse); } 1961070SN/A bool isInvalidate() const { return testCmdAttrib(IsInvalidate); } 1971070SN/A bool isEviction() const { return testCmdAttrib(IsEviction); } 1981070SN/A 1991070SN/A /** 2001070SN/A * A writeback is an eviction that carries data. 2011070SN/A */ 2021070SN/A bool isWriteback() const { return testCmdAttrib(IsEviction) && 2031070SN/A testCmdAttrib(HasData); } 2041070SN/A 2052378SN/A /** 2062378SN/A * Check if this particular packet type carries payload data. Note 2072378SN/A * that this does not reflect if the data pointer of the packet is 2082378SN/A * valid or not. 2092378SN/A */ 2102378SN/A bool hasData() const { return testCmdAttrib(HasData); } 2111806SN/A bool isLLSC() const { return testCmdAttrib(IsLlsc); } 2121070SN/A bool isSWPrefetch() const { return testCmdAttrib(IsSWPrefetch); } 2131070SN/A bool isHWPrefetch() const { return testCmdAttrib(IsHWPrefetch); } 2141070SN/A bool isPrefetch() const { return testCmdAttrib(IsSWPrefetch) || 2151070SN/A testCmdAttrib(IsHWPrefetch); } 2161070SN/A bool isError() const { return testCmdAttrib(IsError); } 2172SN/A bool isPrint() const { return testCmdAttrib(IsPrint); } 21877SN/A bool isFlush() const { return testCmdAttrib(IsFlush); } 2192SN/A 2202SN/A const Command 2212SN/A responseCommand() const 2222SN/A { 2232SN/A return commandInfo[cmd].response; 2242SN/A } 2252SN/A 2262SN/A /// Return the string to a cmd given by idx. 2272SN/A const std::string &toString() const { return commandInfo[cmd].str; } 2282SN/A int toInt() const { return (int)cmd; } 2292158SN/A 2302158SN/A MemCmd(Command _cmd) : cmd(_cmd) { } 2312SN/A MemCmd(int _cmd) : cmd((Command)_cmd) { } 2322SN/A MemCmd() : cmd(InvalidCmd) { } 2332SN/A 234 bool operator==(MemCmd c2) const { return (cmd == c2.cmd); } 235 bool operator!=(MemCmd c2) const { return (cmd != c2.cmd); } 236}; 237 238/** 239 * A Packet is used to encapsulate a transfer between two objects in 240 * the memory system (e.g., the L1 and L2 cache). (In contrast, a 241 * single Request travels all the way from the requester to the 242 * ultimate destination and back, possibly being conveyed by several 243 * different Packets along the way.) 244 */ 245class Packet : public Printable 246{ 247 public: 248 typedef uint32_t FlagsType; 249 typedef ::Flags<FlagsType> Flags; 250 251 private: 252 253 enum : FlagsType { 254 // Flags to transfer across when copying a packet 255 COPY_FLAGS = 0x0000000F, 256 257 SHARED = 0x00000001, 258 // Special control flags 259 /// Special timing-mode atomic snoop for multi-level coherence. 260 EXPRESS_SNOOP = 0x00000002, 261 /// Does supplier have exclusive copy? 262 /// Useful for multi-level coherence. 263 SUPPLY_EXCLUSIVE = 0x00000004, 264 // Snoop response flags 265 MEM_INHIBIT = 0x00000008, 266 267 /// Are the 'addr' and 'size' fields valid? 268 VALID_ADDR = 0x00000100, 269 VALID_SIZE = 0x00000200, 270 271 /// Is the data pointer set to a value that shouldn't be freed 272 /// when the packet is destroyed? 273 STATIC_DATA = 0x00001000, 274 /// The data pointer points to a value that should be freed when 275 /// the packet is destroyed. The pointer is assumed to be pointing 276 /// to an array, and delete [] is consequently called 277 DYNAMIC_DATA = 0x00002000, 278 279 /// suppress the error if this packet encounters a functional 280 /// access failure. 281 SUPPRESS_FUNC_ERROR = 0x00008000, 282 283 // Signal block present to squash prefetch and cache evict packets 284 // through express snoop flag 285 BLOCK_CACHED = 0x00010000 286 }; 287 288 Flags flags; 289 290 public: 291 typedef MemCmd::Command Command; 292 293 /// The command field of the packet. 294 MemCmd cmd; 295 296 /// A pointer to the original request. 297 const RequestPtr req; 298 299 private: 300 /** 301 * A pointer to the data being transfered. It can be differnt 302 * sizes at each level of the heirarchy so it belongs in the 303 * packet, not request. This may or may not be populated when a 304 * responder recieves the packet. If not populated it memory should 305 * be allocated. 306 */ 307 PacketDataPtr data; 308 309 /// The address of the request. This address could be virtual or 310 /// physical, depending on the system configuration. 311 Addr addr; 312 313 /// True if the request targets the secure memory space. 314 bool _isSecure; 315 316 /// The size of the request or transfer. 317 unsigned size; 318 319 /** 320 * Track the bytes found that satisfy a functional read. 321 */ 322 std::vector<bool> bytesValid; 323 324 public: 325 326 /** 327 * The extra delay from seeing the packet until the header is 328 * transmitted. This delay is used to communicate the crossbar 329 * forwarding latency to the neighbouring object (e.g. a cache) 330 * that actually makes the packet wait. As the delay is relative, 331 * a 32-bit unsigned should be sufficient. 332 */ 333 uint32_t headerDelay; 334 335 /** 336 * Keep track of the extra delay incurred by snooping upwards 337 * before sending a request down the memory system. This is used 338 * by the coherent crossbar to account for the additional request 339 * delay. 340 */ 341 uint32_t snoopDelay; 342 343 /** 344 * The extra pipelining delay from seeing the packet until the end of 345 * payload is transmitted by the component that provided it (if 346 * any). This includes the header delay. Similar to the header 347 * delay, this is used to make up for the fact that the 348 * crossbar does not make the packet wait. As the delay is 349 * relative, a 32-bit unsigned should be sufficient. 350 */ 351 uint32_t payloadDelay; 352 353 /** 354 * A virtual base opaque structure used to hold state associated 355 * with the packet (e.g., an MSHR), specific to a MemObject that 356 * sees the packet. A pointer to this state is returned in the 357 * packet's response so that the MemObject in question can quickly 358 * look up the state needed to process it. A specific subclass 359 * would be derived from this to carry state specific to a 360 * particular sending device. 361 * 362 * As multiple MemObjects may add their SenderState throughout the 363 * memory system, the SenderStates create a stack, where a 364 * MemObject can add a new Senderstate, as long as the 365 * predecessing SenderState is restored when the response comes 366 * back. For this reason, the predecessor should always be 367 * populated with the current SenderState of a packet before 368 * modifying the senderState field in the request packet. 369 */ 370 struct SenderState 371 { 372 SenderState* predecessor; 373 SenderState() : predecessor(NULL) {} 374 virtual ~SenderState() {} 375 }; 376 377 /** 378 * Object used to maintain state of a PrintReq. The senderState 379 * field of a PrintReq should always be of this type. 380 */ 381 class PrintReqState : public SenderState 382 { 383 private: 384 /** 385 * An entry in the label stack. 386 */ 387 struct LabelStackEntry 388 { 389 const std::string label; 390 std::string *prefix; 391 bool labelPrinted; 392 LabelStackEntry(const std::string &_label, std::string *_prefix); 393 }; 394 395 typedef std::list<LabelStackEntry> LabelStack; 396 LabelStack labelStack; 397 398 std::string *curPrefixPtr; 399 400 public: 401 std::ostream &os; 402 const int verbosity; 403 404 PrintReqState(std::ostream &os, int verbosity = 0); 405 ~PrintReqState(); 406 407 /** 408 * Returns the current line prefix. 409 */ 410 const std::string &curPrefix() { return *curPrefixPtr; } 411 412 /** 413 * Push a label onto the label stack, and prepend the given 414 * prefix string onto the current prefix. Labels will only be 415 * printed if an object within the label's scope is printed. 416 */ 417 void pushLabel(const std::string &lbl, 418 const std::string &prefix = " "); 419 420 /** 421 * Pop a label off the label stack. 422 */ 423 void popLabel(); 424 425 /** 426 * Print all of the pending unprinted labels on the 427 * stack. Called by printObj(), so normally not called by 428 * users unless bypassing printObj(). 429 */ 430 void printLabels(); 431 432 /** 433 * Print a Printable object to os, because it matched the 434 * address on a PrintReq. 435 */ 436 void printObj(Printable *obj); 437 }; 438 439 /** 440 * This packet's sender state. Devices should use dynamic_cast<> 441 * to cast to the state appropriate to the sender. The intent of 442 * this variable is to allow a device to attach extra information 443 * to a request. A response packet must return the sender state 444 * that was attached to the original request (even if a new packet 445 * is created). 446 */ 447 SenderState *senderState; 448 449 /** 450 * Push a new sender state to the packet and make the current 451 * sender state the predecessor of the new one. This should be 452 * prefered over direct manipulation of the senderState member 453 * variable. 454 * 455 * @param sender_state SenderState to push at the top of the stack 456 */ 457 void pushSenderState(SenderState *sender_state); 458 459 /** 460 * Pop the top of the state stack and return a pointer to it. This 461 * assumes the current sender state is not NULL. This should be 462 * preferred over direct manipulation of the senderState member 463 * variable. 464 * 465 * @return The current top of the stack 466 */ 467 SenderState *popSenderState(); 468 469 /** 470 * Go through the sender state stack and return the first instance 471 * that is of type T (as determined by a dynamic_cast). If there 472 * is no sender state of type T, NULL is returned. 473 * 474 * @return The topmost state of type T 475 */ 476 template <typename T> 477 T * findNextSenderState() const 478 { 479 T *t = NULL; 480 SenderState* sender_state = senderState; 481 while (t == NULL && sender_state != NULL) { 482 t = dynamic_cast<T*>(sender_state); 483 sender_state = sender_state->predecessor; 484 } 485 return t; 486 } 487 488 /// Return the string name of the cmd field (for debugging and 489 /// tracing). 490 const std::string &cmdString() const { return cmd.toString(); } 491 492 /// Return the index of this command. 493 inline int cmdToIndex() const { return cmd.toInt(); } 494 495 bool isRead() const { return cmd.isRead(); } 496 bool isWrite() const { return cmd.isWrite(); } 497 bool isUpgrade() const { return cmd.isUpgrade(); } 498 bool isRequest() const { return cmd.isRequest(); } 499 bool isResponse() const { return cmd.isResponse(); } 500 bool needsExclusive() const { return cmd.needsExclusive(); } 501 bool needsResponse() const { return cmd.needsResponse(); } 502 bool isInvalidate() const { return cmd.isInvalidate(); } 503 bool isEviction() const { return cmd.isEviction(); } 504 bool isWriteback() const { return cmd.isWriteback(); } 505 bool hasData() const { return cmd.hasData(); } 506 bool isLLSC() const { return cmd.isLLSC(); } 507 bool isError() const { return cmd.isError(); } 508 bool isPrint() const { return cmd.isPrint(); } 509 bool isFlush() const { return cmd.isFlush(); } 510 511 // Snoop flags 512 void assertMemInhibit() 513 { 514 assert(isRequest()); 515 assert(!flags.isSet(MEM_INHIBIT)); 516 flags.set(MEM_INHIBIT); 517 } 518 bool memInhibitAsserted() const { return flags.isSet(MEM_INHIBIT); } 519 void assertShared() { flags.set(SHARED); } 520 bool sharedAsserted() const { return flags.isSet(SHARED); } 521 522 // Special control flags 523 void setExpressSnoop() { flags.set(EXPRESS_SNOOP); } 524 bool isExpressSnoop() const { return flags.isSet(EXPRESS_SNOOP); } 525 void setSupplyExclusive() { flags.set(SUPPLY_EXCLUSIVE); } 526 bool isSupplyExclusive() const { return flags.isSet(SUPPLY_EXCLUSIVE); } 527 void setSuppressFuncError() { flags.set(SUPPRESS_FUNC_ERROR); } 528 bool suppressFuncError() const { return flags.isSet(SUPPRESS_FUNC_ERROR); } 529 void setBlockCached() { flags.set(BLOCK_CACHED); } 530 bool isBlockCached() const { return flags.isSet(BLOCK_CACHED); } 531 void clearBlockCached() { flags.clear(BLOCK_CACHED); } 532 533 // Network error conditions... encapsulate them as methods since 534 // their encoding keeps changing (from result field to command 535 // field, etc.) 536 void 537 setBadAddress() 538 { 539 assert(isResponse()); 540 cmd = MemCmd::BadAddressError; 541 } 542 543 void copyError(Packet *pkt) { assert(pkt->isError()); cmd = pkt->cmd; } 544 545 Addr getAddr() const { assert(flags.isSet(VALID_ADDR)); return addr; } 546 /** 547 * Update the address of this packet mid-transaction. This is used 548 * by the address mapper to change an already set address to a new 549 * one based on the system configuration. It is intended to remap 550 * an existing address, so it asserts that the current address is 551 * valid. 552 */ 553 void setAddr(Addr _addr) { assert(flags.isSet(VALID_ADDR)); addr = _addr; } 554 555 unsigned getSize() const { assert(flags.isSet(VALID_SIZE)); return size; } 556 557 Addr getOffset(unsigned int blk_size) const 558 { 559 return getAddr() & Addr(blk_size - 1); 560 } 561 562 Addr getBlockAddr(unsigned int blk_size) const 563 { 564 return getAddr() & ~(Addr(blk_size - 1)); 565 } 566 567 bool isSecure() const 568 { 569 assert(flags.isSet(VALID_ADDR)); 570 return _isSecure; 571 } 572 573 /** 574 * It has been determined that the SC packet should successfully update 575 * memory. Therefore, convert this SC packet to a normal write. 576 */ 577 void 578 convertScToWrite() 579 { 580 assert(isLLSC()); 581 assert(isWrite()); 582 cmd = MemCmd::WriteReq; 583 } 584 585 /** 586 * When ruby is in use, Ruby will monitor the cache line and the 587 * phys memory should treat LL ops as normal reads. 588 */ 589 void 590 convertLlToRead() 591 { 592 assert(isLLSC()); 593 assert(isRead()); 594 cmd = MemCmd::ReadReq; 595 } 596 597 /** 598 * Constructor. Note that a Request object must be constructed 599 * first, but the Requests's physical address and size fields need 600 * not be valid. The command must be supplied. 601 */ 602 Packet(const RequestPtr _req, MemCmd _cmd) 603 : cmd(_cmd), req(_req), data(nullptr), addr(0), _isSecure(false), 604 size(0), headerDelay(0), snoopDelay(0), payloadDelay(0), 605 senderState(NULL) 606 { 607 if (req->hasPaddr()) { 608 addr = req->getPaddr(); 609 flags.set(VALID_ADDR); 610 _isSecure = req->isSecure(); 611 } 612 if (req->hasSize()) { 613 size = req->getSize(); 614 flags.set(VALID_SIZE); 615 } 616 } 617 618 /** 619 * Alternate constructor if you are trying to create a packet with 620 * a request that is for a whole block, not the address from the 621 * req. this allows for overriding the size/addr of the req. 622 */ 623 Packet(const RequestPtr _req, MemCmd _cmd, int _blkSize) 624 : cmd(_cmd), req(_req), data(nullptr), addr(0), _isSecure(false), 625 headerDelay(0), snoopDelay(0), payloadDelay(0), 626 senderState(NULL) 627 { 628 if (req->hasPaddr()) { 629 addr = req->getPaddr() & ~(_blkSize - 1); 630 flags.set(VALID_ADDR); 631 _isSecure = req->isSecure(); 632 } 633 size = _blkSize; 634 flags.set(VALID_SIZE); 635 } 636 637 /** 638 * Alternate constructor for copying a packet. Copy all fields 639 * *except* if the original packet's data was dynamic, don't copy 640 * that, as we can't guarantee that the new packet's lifetime is 641 * less than that of the original packet. In this case the new 642 * packet should allocate its own data. 643 */ 644 Packet(const PacketPtr pkt, bool clear_flags, bool alloc_data) 645 : cmd(pkt->cmd), req(pkt->req), 646 data(nullptr), 647 addr(pkt->addr), _isSecure(pkt->_isSecure), size(pkt->size), 648 bytesValid(pkt->bytesValid), 649 headerDelay(pkt->headerDelay), 650 snoopDelay(0), 651 payloadDelay(pkt->payloadDelay), 652 senderState(pkt->senderState) 653 { 654 if (!clear_flags) 655 flags.set(pkt->flags & COPY_FLAGS); 656 657 flags.set(pkt->flags & (VALID_ADDR|VALID_SIZE)); 658 659 // should we allocate space for data, or not, the express 660 // snoops do not need to carry any data as they only serve to 661 // co-ordinate state changes 662 if (alloc_data) { 663 // even if asked to allocate data, if the original packet 664 // holds static data, then the sender will not be doing 665 // any memcpy on receiving the response, thus we simply 666 // carry the pointer forward 667 if (pkt->flags.isSet(STATIC_DATA)) { 668 data = pkt->data; 669 flags.set(STATIC_DATA); 670 } else { 671 allocate(); 672 } 673 } 674 } 675 676 /** 677 * Generate the appropriate read MemCmd based on the Request flags. 678 */ 679 static MemCmd 680 makeReadCmd(const RequestPtr req) 681 { 682 if (req->isLLSC()) 683 return MemCmd::LoadLockedReq; 684 else if (req->isPrefetch()) 685 return MemCmd::SoftPFReq; 686 else 687 return MemCmd::ReadReq; 688 } 689 690 /** 691 * Generate the appropriate write MemCmd based on the Request flags. 692 */ 693 static MemCmd 694 makeWriteCmd(const RequestPtr req) 695 { 696 if (req->isLLSC()) 697 return MemCmd::StoreCondReq; 698 else if (req->isSwap()) 699 return MemCmd::SwapReq; 700 else 701 return MemCmd::WriteReq; 702 } 703 704 /** 705 * Constructor-like methods that return Packets based on Request objects. 706 * Fine-tune the MemCmd type if it's not a vanilla read or write. 707 */ 708 static PacketPtr 709 createRead(const RequestPtr req) 710 { 711 return new Packet(req, makeReadCmd(req)); 712 } 713 714 static PacketPtr 715 createWrite(const RequestPtr req) 716 { 717 return new Packet(req, makeWriteCmd(req)); 718 } 719 720 /** 721 * clean up packet variables 722 */ 723 ~Packet() 724 { 725 // Delete the request object if this is a request packet which 726 // does not need a response, because the requester will not get 727 // a chance. If the request packet needs a response then the 728 // request will be deleted on receipt of the response 729 // packet. We also make sure to never delete the request for 730 // express snoops, even for cases when responses are not 731 // needed (CleanEvict and Writeback), since the snoop packet 732 // re-uses the same request. 733 if (req && isRequest() && !needsResponse() && 734 !isExpressSnoop()) { 735 delete req; 736 } 737 deleteData(); 738 } 739 740 /** 741 * Take a request packet and modify it in place to be suitable for 742 * returning as a response to that request. 743 */ 744 void 745 makeResponse() 746 { 747 assert(needsResponse()); 748 assert(isRequest()); 749 cmd = cmd.responseCommand(); 750 751 // responses are never express, even if the snoop that 752 // triggered them was 753 flags.clear(EXPRESS_SNOOP); 754 } 755 756 void 757 makeAtomicResponse() 758 { 759 makeResponse(); 760 } 761 762 void 763 makeTimingResponse() 764 { 765 makeResponse(); 766 } 767 768 void 769 setFunctionalResponseStatus(bool success) 770 { 771 if (!success) { 772 if (isWrite()) { 773 cmd = MemCmd::FunctionalWriteError; 774 } else { 775 cmd = MemCmd::FunctionalReadError; 776 } 777 } 778 } 779 780 void 781 setSize(unsigned size) 782 { 783 assert(!flags.isSet(VALID_SIZE)); 784 785 this->size = size; 786 flags.set(VALID_SIZE); 787 } 788 789 790 public: 791 /** 792 * @{ 793 * @name Data accessor mehtods 794 */ 795 796 /** 797 * Set the data pointer to the following value that should not be 798 * freed. Static data allows us to do a single memcpy even if 799 * multiple packets are required to get from source to destination 800 * and back. In essence the pointer is set calling dataStatic on 801 * the original packet, and whenever this packet is copied and 802 * forwarded the same pointer is passed on. When a packet 803 * eventually reaches the destination holding the data, it is 804 * copied once into the location originally set. On the way back 805 * to the source, no copies are necessary. 806 */ 807 template <typename T> 808 void 809 dataStatic(T *p) 810 { 811 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 812 data = (PacketDataPtr)p; 813 flags.set(STATIC_DATA); 814 } 815 816 /** 817 * Set the data pointer to the following value that should not be 818 * freed. This version of the function allows the pointer passed 819 * to us to be const. To avoid issues down the line we cast the 820 * constness away, the alternative would be to keep both a const 821 * and non-const data pointer and cleverly choose between 822 * them. Note that this is only allowed for static data. 823 */ 824 template <typename T> 825 void 826 dataStaticConst(const T *p) 827 { 828 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 829 data = const_cast<PacketDataPtr>(p); 830 flags.set(STATIC_DATA); 831 } 832 833 /** 834 * Set the data pointer to a value that should have delete [] 835 * called on it. Dynamic data is local to this packet, and as the 836 * packet travels from source to destination, forwarded packets 837 * will allocate their own data. When a packet reaches the final 838 * destination it will populate the dynamic data of that specific 839 * packet, and on the way back towards the source, memcpy will be 840 * invoked in every step where a new packet was created e.g. in 841 * the caches. Ultimately when the response reaches the source a 842 * final memcpy is needed to extract the data from the packet 843 * before it is deallocated. 844 */ 845 template <typename T> 846 void 847 dataDynamic(T *p) 848 { 849 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 850 data = (PacketDataPtr)p; 851 flags.set(DYNAMIC_DATA); 852 } 853 854 /** 855 * get a pointer to the data ptr. 856 */ 857 template <typename T> 858 T* 859 getPtr() 860 { 861 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA)); 862 return (T*)data; 863 } 864 865 template <typename T> 866 const T* 867 getConstPtr() const 868 { 869 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA)); 870 return (const T*)data; 871 } 872 873 /** 874 * Get the data in the packet byte swapped from big endian to 875 * host endian. 876 */ 877 template <typename T> 878 T getBE() const; 879 880 /** 881 * Get the data in the packet byte swapped from little endian to 882 * host endian. 883 */ 884 template <typename T> 885 T getLE() const; 886 887 /** 888 * Get the data in the packet byte swapped from the specified 889 * endianness. 890 */ 891 template <typename T> 892 T get(ByteOrder endian) const; 893 894 /** 895 * Get the data in the packet byte swapped from guest to host 896 * endian. 897 */ 898 template <typename T> 899 T get() const; 900 901 /** Set the value in the data pointer to v as big endian. */ 902 template <typename T> 903 void setBE(T v); 904 905 /** Set the value in the data pointer to v as little endian. */ 906 template <typename T> 907 void setLE(T v); 908 909 /** 910 * Set the value in the data pointer to v using the specified 911 * endianness. 912 */ 913 template <typename T> 914 void set(T v, ByteOrder endian); 915 916 /** Set the value in the data pointer to v as guest endian. */ 917 template <typename T> 918 void set(T v); 919 920 /** 921 * Copy data into the packet from the provided pointer. 922 */ 923 void 924 setData(const uint8_t *p) 925 { 926 // we should never be copying data onto itself, which means we 927 // must idenfity packets with static data, as they carry the 928 // same pointer from source to destination and back 929 assert(p != getPtr<uint8_t>() || flags.isSet(STATIC_DATA)); 930 931 if (p != getPtr<uint8_t>()) 932 // for packet with allocated dynamic data, we copy data from 933 // one to the other, e.g. a forwarded response to a response 934 std::memcpy(getPtr<uint8_t>(), p, getSize()); 935 } 936 937 /** 938 * Copy data into the packet from the provided block pointer, 939 * which is aligned to the given block size. 940 */ 941 void 942 setDataFromBlock(const uint8_t *blk_data, int blkSize) 943 { 944 setData(blk_data + getOffset(blkSize)); 945 } 946 947 /** 948 * Copy data from the packet to the provided block pointer, which 949 * is aligned to the given block size. 950 */ 951 void 952 writeData(uint8_t *p) const 953 { 954 std::memcpy(p, getConstPtr<uint8_t>(), getSize()); 955 } 956 957 /** 958 * Copy data from the packet to the memory at the provided pointer. 959 */ 960 void 961 writeDataToBlock(uint8_t *blk_data, int blkSize) const 962 { 963 writeData(blk_data + getOffset(blkSize)); 964 } 965 966 /** 967 * delete the data pointed to in the data pointer. Ok to call to 968 * matter how data was allocted. 969 */ 970 void 971 deleteData() 972 { 973 if (flags.isSet(DYNAMIC_DATA)) 974 delete [] data; 975 976 flags.clear(STATIC_DATA|DYNAMIC_DATA); 977 data = NULL; 978 } 979 980 /** Allocate memory for the packet. */ 981 void 982 allocate() 983 { 984 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 985 flags.set(DYNAMIC_DATA); 986 data = new uint8_t[getSize()]; 987 } 988 989 /** @} */ 990 991 private: // Private data accessor methods 992 /** Get the data in the packet without byte swapping. */ 993 template <typename T> 994 T getRaw() const; 995 996 /** Set the value in the data pointer to v without byte swapping. */ 997 template <typename T> 998 void setRaw(T v); 999 1000 public: 1001 /** 1002 * Check a functional request against a memory value stored in 1003 * another packet (i.e. an in-transit request or 1004 * response). Returns true if the current packet is a read, and 1005 * the other packet provides the data, which is then copied to the 1006 * current packet. If the current packet is a write, and the other 1007 * packet intersects this one, then we update the data 1008 * accordingly. 1009 */ 1010 bool 1011 checkFunctional(PacketPtr other) 1012 { 1013 // all packets that are carrying a payload should have a valid 1014 // data pointer 1015 return checkFunctional(other, other->getAddr(), other->isSecure(), 1016 other->getSize(), 1017 other->hasData() ? 1018 other->getPtr<uint8_t>() : NULL); 1019 } 1020 1021 /** 1022 * Does the request need to check for cached copies of the same block 1023 * in the memory hierarchy above. 1024 **/ 1025 bool 1026 mustCheckAbove() const 1027 { 1028 return cmd == MemCmd::HardPFReq || isEviction(); 1029 } 1030 1031 /** 1032 * Is this packet a clean eviction, including both actual clean 1033 * evict packets, but also clean writebacks. 1034 */ 1035 bool 1036 isCleanEviction() const 1037 { 1038 return cmd == MemCmd::CleanEvict || cmd == MemCmd::WritebackClean; 1039 } 1040 1041 /** 1042 * Check a functional request against a memory value represented 1043 * by a base/size pair and an associated data array. If the 1044 * current packet is a read, it may be satisfied by the memory 1045 * value. If the current packet is a write, it may update the 1046 * memory value. 1047 */ 1048 bool 1049 checkFunctional(Printable *obj, Addr base, bool is_secure, int size, 1050 uint8_t *_data); 1051 1052 /** 1053 * Push label for PrintReq (safe to call unconditionally). 1054 */ 1055 void 1056 pushLabel(const std::string &lbl) 1057 { 1058 if (isPrint()) 1059 safe_cast<PrintReqState*>(senderState)->pushLabel(lbl); 1060 } 1061 1062 /** 1063 * Pop label for PrintReq (safe to call unconditionally). 1064 */ 1065 void 1066 popLabel() 1067 { 1068 if (isPrint()) 1069 safe_cast<PrintReqState*>(senderState)->popLabel(); 1070 } 1071 1072 void print(std::ostream &o, int verbosity = 0, 1073 const std::string &prefix = "") const; 1074 1075 /** 1076 * A no-args wrapper of print(std::ostream...) 1077 * meant to be invoked from DPRINTFs 1078 * avoiding string overheads in fast mode 1079 * @return string with the request's type and start<->end addresses 1080 */ 1081 std::string print() const; 1082}; 1083 1084#endif //__MEM_PACKET_HH 1085