packet.hh revision 13235:83ad50c4a285
1/* 2 * Copyright (c) 2012-2018 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 * Copyright (c) 2006 The Regents of The University of Michigan 15 * Copyright (c) 2010,2015 Advanced Micro Devices, Inc. 16 * All rights reserved. 17 * 18 * Redistribution and use in source and binary forms, with or without 19 * modification, are permitted provided that the following conditions are 20 * met: redistributions of source code must retain the above copyright 21 * notice, this list of conditions and the following disclaimer; 22 * redistributions in binary form must reproduce the above copyright 23 * notice, this list of conditions and the following disclaimer in the 24 * documentation and/or other materials provided with the distribution; 25 * neither the name of the copyright holders nor the names of its 26 * contributors may be used to endorse or promote products derived from 27 * this software without specific prior written permission. 28 * 29 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 30 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 31 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 32 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 33 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 34 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 35 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 36 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 37 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 38 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 39 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 40 * 41 * Authors: Ron Dreslinski 42 * Steve Reinhardt 43 * Ali Saidi 44 * Andreas Hansson 45 * Nikos Nikoleris 46 */ 47 48/** 49 * @file 50 * Declaration of the Packet class. 51 */ 52 53#ifndef __MEM_PACKET_HH__ 54#define __MEM_PACKET_HH__ 55 56#include <bitset> 57#include <cassert> 58#include <list> 59 60#include "base/cast.hh" 61#include "base/compiler.hh" 62#include "base/flags.hh" 63#include "base/logging.hh" 64#include "base/printable.hh" 65#include "base/types.hh" 66#include "mem/request.hh" 67#include "sim/core.hh" 68 69class Packet; 70typedef Packet *PacketPtr; 71typedef uint8_t* PacketDataPtr; 72typedef std::list<PacketPtr> PacketList; 73typedef uint64_t PacketId; 74 75class MemCmd 76{ 77 friend class Packet; 78 79 public: 80 /** 81 * List of all commands associated with a packet. 82 */ 83 enum Command 84 { 85 InvalidCmd, 86 ReadReq, 87 ReadResp, 88 ReadRespWithInvalidate, 89 WriteReq, 90 WriteResp, 91 WritebackDirty, 92 WritebackClean, 93 WriteClean, // writes dirty data below without evicting 94 CleanEvict, 95 SoftPFReq, 96 HardPFReq, 97 SoftPFResp, 98 HardPFResp, 99 WriteLineReq, 100 UpgradeReq, 101 SCUpgradeReq, // Special "weak" upgrade for StoreCond 102 UpgradeResp, 103 SCUpgradeFailReq, // Failed SCUpgradeReq in MSHR (never sent) 104 UpgradeFailResp, // Valid for SCUpgradeReq only 105 ReadExReq, 106 ReadExResp, 107 ReadCleanReq, 108 ReadSharedReq, 109 LoadLockedReq, 110 StoreCondReq, 111 StoreCondFailReq, // Failed StoreCondReq in MSHR (never sent) 112 StoreCondResp, 113 SwapReq, 114 SwapResp, 115 MessageReq, 116 MessageResp, 117 MemFenceReq, 118 MemFenceResp, 119 CleanSharedReq, 120 CleanSharedResp, 121 CleanInvalidReq, 122 CleanInvalidResp, 123 // Error responses 124 // @TODO these should be classified as responses rather than 125 // requests; coding them as requests initially for backwards 126 // compatibility 127 InvalidDestError, // packet dest field invalid 128 BadAddressError, // memory address invalid 129 FunctionalReadError, // unable to fulfill functional read 130 FunctionalWriteError, // unable to fulfill functional write 131 // Fake simulator-only commands 132 PrintReq, // Print state matching address 133 FlushReq, //request for a cache flush 134 InvalidateReq, // request for address to be invalidated 135 InvalidateResp, 136 NUM_MEM_CMDS 137 }; 138 139 private: 140 /** 141 * List of command attributes. 142 */ 143 enum Attribute 144 { 145 IsRead, //!< Data flows from responder to requester 146 IsWrite, //!< Data flows from requester to responder 147 IsUpgrade, 148 IsInvalidate, 149 IsClean, //!< Cleans any existing dirty blocks 150 NeedsWritable, //!< Requires writable copy to complete in-cache 151 IsRequest, //!< Issued by requester 152 IsResponse, //!< Issue by responder 153 NeedsResponse, //!< Requester needs response from target 154 IsEviction, 155 IsSWPrefetch, 156 IsHWPrefetch, 157 IsLlsc, //!< Alpha/MIPS LL or SC access 158 HasData, //!< There is an associated payload 159 IsError, //!< Error response 160 IsPrint, //!< Print state matching address (for debugging) 161 IsFlush, //!< Flush the address from caches 162 FromCache, //!< Request originated from a caching agent 163 NUM_COMMAND_ATTRIBUTES 164 }; 165 166 /** 167 * Structure that defines attributes and other data associated 168 * with a Command. 169 */ 170 struct CommandInfo 171 { 172 /// Set of attribute flags. 173 const std::bitset<NUM_COMMAND_ATTRIBUTES> attributes; 174 /// Corresponding response for requests; InvalidCmd if no 175 /// response is applicable. 176 const Command response; 177 /// String representation (for printing) 178 const std::string str; 179 }; 180 181 /// Array to map Command enum to associated info. 182 static const CommandInfo commandInfo[]; 183 184 private: 185 186 Command cmd; 187 188 bool 189 testCmdAttrib(MemCmd::Attribute attrib) const 190 { 191 return commandInfo[cmd].attributes[attrib] != 0; 192 } 193 194 public: 195 196 bool isRead() const { return testCmdAttrib(IsRead); } 197 bool isWrite() const { return testCmdAttrib(IsWrite); } 198 bool isUpgrade() const { return testCmdAttrib(IsUpgrade); } 199 bool isRequest() const { return testCmdAttrib(IsRequest); } 200 bool isResponse() const { return testCmdAttrib(IsResponse); } 201 bool needsWritable() const { return testCmdAttrib(NeedsWritable); } 202 bool needsResponse() const { return testCmdAttrib(NeedsResponse); } 203 bool isInvalidate() const { return testCmdAttrib(IsInvalidate); } 204 bool isEviction() const { return testCmdAttrib(IsEviction); } 205 bool isClean() const { return testCmdAttrib(IsClean); } 206 bool fromCache() const { return testCmdAttrib(FromCache); } 207 208 /** 209 * A writeback is an eviction that carries data. 210 */ 211 bool isWriteback() const { return testCmdAttrib(IsEviction) && 212 testCmdAttrib(HasData); } 213 214 /** 215 * Check if this particular packet type carries payload data. Note 216 * that this does not reflect if the data pointer of the packet is 217 * valid or not. 218 */ 219 bool hasData() const { return testCmdAttrib(HasData); } 220 bool isLLSC() const { return testCmdAttrib(IsLlsc); } 221 bool isSWPrefetch() const { return testCmdAttrib(IsSWPrefetch); } 222 bool isHWPrefetch() const { return testCmdAttrib(IsHWPrefetch); } 223 bool isPrefetch() const { return testCmdAttrib(IsSWPrefetch) || 224 testCmdAttrib(IsHWPrefetch); } 225 bool isError() const { return testCmdAttrib(IsError); } 226 bool isPrint() const { return testCmdAttrib(IsPrint); } 227 bool isFlush() const { return testCmdAttrib(IsFlush); } 228 229 Command 230 responseCommand() const 231 { 232 return commandInfo[cmd].response; 233 } 234 235 /// Return the string to a cmd given by idx. 236 const std::string &toString() const { return commandInfo[cmd].str; } 237 int toInt() const { return (int)cmd; } 238 239 MemCmd(Command _cmd) : cmd(_cmd) { } 240 MemCmd(int _cmd) : cmd((Command)_cmd) { } 241 MemCmd() : cmd(InvalidCmd) { } 242 243 bool operator==(MemCmd c2) const { return (cmd == c2.cmd); } 244 bool operator!=(MemCmd c2) const { return (cmd != c2.cmd); } 245}; 246 247/** 248 * A Packet is used to encapsulate a transfer between two objects in 249 * the memory system (e.g., the L1 and L2 cache). (In contrast, a 250 * single Request travels all the way from the requester to the 251 * ultimate destination and back, possibly being conveyed by several 252 * different Packets along the way.) 253 */ 254class Packet : public Printable 255{ 256 public: 257 typedef uint32_t FlagsType; 258 typedef ::Flags<FlagsType> Flags; 259 260 private: 261 262 enum : FlagsType { 263 // Flags to transfer across when copying a packet 264 COPY_FLAGS = 0x0000003F, 265 266 // Does this packet have sharers (which means it should not be 267 // considered writable) or not. See setHasSharers below. 268 HAS_SHARERS = 0x00000001, 269 270 // Special control flags 271 /// Special timing-mode atomic snoop for multi-level coherence. 272 EXPRESS_SNOOP = 0x00000002, 273 274 /// Allow a responding cache to inform the cache hierarchy 275 /// that it had a writable copy before responding. See 276 /// setResponderHadWritable below. 277 RESPONDER_HAD_WRITABLE = 0x00000004, 278 279 // Snoop co-ordination flag to indicate that a cache is 280 // responding to a snoop. See setCacheResponding below. 281 CACHE_RESPONDING = 0x00000008, 282 283 // The writeback/writeclean should be propagated further 284 // downstream by the receiver 285 WRITE_THROUGH = 0x00000010, 286 287 // Response co-ordination flag for cache maintenance 288 // operations 289 SATISFIED = 0x00000020, 290 291 /// Are the 'addr' and 'size' fields valid? 292 VALID_ADDR = 0x00000100, 293 VALID_SIZE = 0x00000200, 294 295 /// Is the data pointer set to a value that shouldn't be freed 296 /// when the packet is destroyed? 297 STATIC_DATA = 0x00001000, 298 /// The data pointer points to a value that should be freed when 299 /// the packet is destroyed. The pointer is assumed to be pointing 300 /// to an array, and delete [] is consequently called 301 DYNAMIC_DATA = 0x00002000, 302 303 /// suppress the error if this packet encounters a functional 304 /// access failure. 305 SUPPRESS_FUNC_ERROR = 0x00008000, 306 307 // Signal block present to squash prefetch and cache evict packets 308 // through express snoop flag 309 BLOCK_CACHED = 0x00010000 310 }; 311 312 Flags flags; 313 314 public: 315 typedef MemCmd::Command Command; 316 317 /// The command field of the packet. 318 MemCmd cmd; 319 320 const PacketId id; 321 322 /// A pointer to the original request. 323 RequestPtr req; 324 325 private: 326 /** 327 * A pointer to the data being transferred. It can be different 328 * sizes at each level of the hierarchy so it belongs to the 329 * packet, not request. This may or may not be populated when a 330 * responder receives the packet. If not populated memory should 331 * be allocated. 332 */ 333 PacketDataPtr data; 334 335 /// The address of the request. This address could be virtual or 336 /// physical, depending on the system configuration. 337 Addr addr; 338 339 /// True if the request targets the secure memory space. 340 bool _isSecure; 341 342 /// The size of the request or transfer. 343 unsigned size; 344 345 /** 346 * Track the bytes found that satisfy a functional read. 347 */ 348 std::vector<bool> bytesValid; 349 350 // Quality of Service priority value 351 uint8_t _qosValue; 352 353 public: 354 355 /** 356 * The extra delay from seeing the packet until the header is 357 * transmitted. This delay is used to communicate the crossbar 358 * forwarding latency to the neighbouring object (e.g. a cache) 359 * that actually makes the packet wait. As the delay is relative, 360 * a 32-bit unsigned should be sufficient. 361 */ 362 uint32_t headerDelay; 363 364 /** 365 * Keep track of the extra delay incurred by snooping upwards 366 * before sending a request down the memory system. This is used 367 * by the coherent crossbar to account for the additional request 368 * delay. 369 */ 370 uint32_t snoopDelay; 371 372 /** 373 * The extra pipelining delay from seeing the packet until the end of 374 * payload is transmitted by the component that provided it (if 375 * any). This includes the header delay. Similar to the header 376 * delay, this is used to make up for the fact that the 377 * crossbar does not make the packet wait. As the delay is 378 * relative, a 32-bit unsigned should be sufficient. 379 */ 380 uint32_t payloadDelay; 381 382 /** 383 * A virtual base opaque structure used to hold state associated 384 * with the packet (e.g., an MSHR), specific to a MemObject that 385 * sees the packet. A pointer to this state is returned in the 386 * packet's response so that the MemObject in question can quickly 387 * look up the state needed to process it. A specific subclass 388 * would be derived from this to carry state specific to a 389 * particular sending device. 390 * 391 * As multiple MemObjects may add their SenderState throughout the 392 * memory system, the SenderStates create a stack, where a 393 * MemObject can add a new Senderstate, as long as the 394 * predecessing SenderState is restored when the response comes 395 * back. For this reason, the predecessor should always be 396 * populated with the current SenderState of a packet before 397 * modifying the senderState field in the request packet. 398 */ 399 struct SenderState 400 { 401 SenderState* predecessor; 402 SenderState() : predecessor(NULL) {} 403 virtual ~SenderState() {} 404 }; 405 406 /** 407 * Object used to maintain state of a PrintReq. The senderState 408 * field of a PrintReq should always be of this type. 409 */ 410 class PrintReqState : public SenderState 411 { 412 private: 413 /** 414 * An entry in the label stack. 415 */ 416 struct LabelStackEntry 417 { 418 const std::string label; 419 std::string *prefix; 420 bool labelPrinted; 421 LabelStackEntry(const std::string &_label, std::string *_prefix); 422 }; 423 424 typedef std::list<LabelStackEntry> LabelStack; 425 LabelStack labelStack; 426 427 std::string *curPrefixPtr; 428 429 public: 430 std::ostream &os; 431 const int verbosity; 432 433 PrintReqState(std::ostream &os, int verbosity = 0); 434 ~PrintReqState(); 435 436 /** 437 * Returns the current line prefix. 438 */ 439 const std::string &curPrefix() { return *curPrefixPtr; } 440 441 /** 442 * Push a label onto the label stack, and prepend the given 443 * prefix string onto the current prefix. Labels will only be 444 * printed if an object within the label's scope is printed. 445 */ 446 void pushLabel(const std::string &lbl, 447 const std::string &prefix = " "); 448 449 /** 450 * Pop a label off the label stack. 451 */ 452 void popLabel(); 453 454 /** 455 * Print all of the pending unprinted labels on the 456 * stack. Called by printObj(), so normally not called by 457 * users unless bypassing printObj(). 458 */ 459 void printLabels(); 460 461 /** 462 * Print a Printable object to os, because it matched the 463 * address on a PrintReq. 464 */ 465 void printObj(Printable *obj); 466 }; 467 468 /** 469 * This packet's sender state. Devices should use dynamic_cast<> 470 * to cast to the state appropriate to the sender. The intent of 471 * this variable is to allow a device to attach extra information 472 * to a request. A response packet must return the sender state 473 * that was attached to the original request (even if a new packet 474 * is created). 475 */ 476 SenderState *senderState; 477 478 /** 479 * Push a new sender state to the packet and make the current 480 * sender state the predecessor of the new one. This should be 481 * prefered over direct manipulation of the senderState member 482 * variable. 483 * 484 * @param sender_state SenderState to push at the top of the stack 485 */ 486 void pushSenderState(SenderState *sender_state); 487 488 /** 489 * Pop the top of the state stack and return a pointer to it. This 490 * assumes the current sender state is not NULL. This should be 491 * preferred over direct manipulation of the senderState member 492 * variable. 493 * 494 * @return The current top of the stack 495 */ 496 SenderState *popSenderState(); 497 498 /** 499 * Go through the sender state stack and return the first instance 500 * that is of type T (as determined by a dynamic_cast). If there 501 * is no sender state of type T, NULL is returned. 502 * 503 * @return The topmost state of type T 504 */ 505 template <typename T> 506 T * findNextSenderState() const 507 { 508 T *t = NULL; 509 SenderState* sender_state = senderState; 510 while (t == NULL && sender_state != NULL) { 511 t = dynamic_cast<T*>(sender_state); 512 sender_state = sender_state->predecessor; 513 } 514 return t; 515 } 516 517 /// Return the string name of the cmd field (for debugging and 518 /// tracing). 519 const std::string &cmdString() const { return cmd.toString(); } 520 521 /// Return the index of this command. 522 inline int cmdToIndex() const { return cmd.toInt(); } 523 524 bool isRead() const { return cmd.isRead(); } 525 bool isWrite() const { return cmd.isWrite(); } 526 bool isUpgrade() const { return cmd.isUpgrade(); } 527 bool isRequest() const { return cmd.isRequest(); } 528 bool isResponse() const { return cmd.isResponse(); } 529 bool needsWritable() const 530 { 531 // we should never check if a response needsWritable, the 532 // request has this flag, and for a response we should rather 533 // look at the hasSharers flag (if not set, the response is to 534 // be considered writable) 535 assert(isRequest()); 536 return cmd.needsWritable(); 537 } 538 bool needsResponse() const { return cmd.needsResponse(); } 539 bool isInvalidate() const { return cmd.isInvalidate(); } 540 bool isEviction() const { return cmd.isEviction(); } 541 bool isClean() const { return cmd.isClean(); } 542 bool fromCache() const { return cmd.fromCache(); } 543 bool isWriteback() const { return cmd.isWriteback(); } 544 bool hasData() const { return cmd.hasData(); } 545 bool hasRespData() const 546 { 547 MemCmd resp_cmd = cmd.responseCommand(); 548 return resp_cmd.hasData(); 549 } 550 bool isLLSC() const { return cmd.isLLSC(); } 551 bool isError() const { return cmd.isError(); } 552 bool isPrint() const { return cmd.isPrint(); } 553 bool isFlush() const { return cmd.isFlush(); } 554 555 //@{ 556 /// Snoop flags 557 /** 558 * Set the cacheResponding flag. This is used by the caches to 559 * signal another cache that they are responding to a request. A 560 * cache will only respond to snoops if it has the line in either 561 * Modified or Owned state. Note that on snoop hits we always pass 562 * the line as Modified and never Owned. In the case of an Owned 563 * line we proceed to invalidate all other copies. 564 * 565 * On a cache fill (see Cache::handleFill), we check hasSharers 566 * first, ignoring the cacheResponding flag if hasSharers is set. 567 * A line is consequently allocated as: 568 * 569 * hasSharers cacheResponding state 570 * true false Shared 571 * true true Shared 572 * false false Exclusive 573 * false true Modified 574 */ 575 void setCacheResponding() 576 { 577 assert(isRequest()); 578 assert(!flags.isSet(CACHE_RESPONDING)); 579 flags.set(CACHE_RESPONDING); 580 } 581 bool cacheResponding() const { return flags.isSet(CACHE_RESPONDING); } 582 /** 583 * On fills, the hasSharers flag is used by the caches in 584 * combination with the cacheResponding flag, as clarified 585 * above. If the hasSharers flag is not set, the packet is passing 586 * writable. Thus, a response from a memory passes the line as 587 * writable by default. 588 * 589 * The hasSharers flag is also used by upstream caches to inform a 590 * downstream cache that they have the block (by calling 591 * setHasSharers on snoop request packets that hit in upstream 592 * cachs tags or MSHRs). If the snoop packet has sharers, a 593 * downstream cache is prevented from passing a dirty line upwards 594 * if it was not explicitly asked for a writable copy. See 595 * Cache::satisfyCpuSideRequest. 596 * 597 * The hasSharers flag is also used on writebacks, in 598 * combination with the WritbackClean or WritebackDirty commands, 599 * to allocate the block downstream either as: 600 * 601 * command hasSharers state 602 * WritebackDirty false Modified 603 * WritebackDirty true Owned 604 * WritebackClean false Exclusive 605 * WritebackClean true Shared 606 */ 607 void setHasSharers() { flags.set(HAS_SHARERS); } 608 bool hasSharers() const { return flags.isSet(HAS_SHARERS); } 609 //@} 610 611 /** 612 * The express snoop flag is used for two purposes. Firstly, it is 613 * used to bypass flow control for normal (non-snoop) requests 614 * going downstream in the memory system. In cases where a cache 615 * is responding to a snoop from another cache (it had a dirty 616 * line), but the line is not writable (and there are possibly 617 * other copies), the express snoop flag is set by the downstream 618 * cache to invalidate all other copies in zero time. Secondly, 619 * the express snoop flag is also set to be able to distinguish 620 * snoop packets that came from a downstream cache, rather than 621 * snoop packets from neighbouring caches. 622 */ 623 void setExpressSnoop() { flags.set(EXPRESS_SNOOP); } 624 bool isExpressSnoop() const { return flags.isSet(EXPRESS_SNOOP); } 625 626 /** 627 * On responding to a snoop request (which only happens for 628 * Modified or Owned lines), make sure that we can transform an 629 * Owned response to a Modified one. If this flag is not set, the 630 * responding cache had the line in the Owned state, and there are 631 * possibly other Shared copies in the memory system. A downstream 632 * cache helps in orchestrating the invalidation of these copies 633 * by sending out the appropriate express snoops. 634 */ 635 void setResponderHadWritable() 636 { 637 assert(cacheResponding()); 638 assert(!responderHadWritable()); 639 flags.set(RESPONDER_HAD_WRITABLE); 640 } 641 bool responderHadWritable() const 642 { return flags.isSet(RESPONDER_HAD_WRITABLE); } 643 644 /** 645 * A writeback/writeclean cmd gets propagated further downstream 646 * by the receiver when the flag is set. 647 */ 648 void setWriteThrough() 649 { 650 assert(cmd.isWrite() && 651 (cmd.isEviction() || cmd == MemCmd::WriteClean)); 652 flags.set(WRITE_THROUGH); 653 } 654 void clearWriteThrough() { flags.clear(WRITE_THROUGH); } 655 bool writeThrough() const { return flags.isSet(WRITE_THROUGH); } 656 657 /** 658 * Set when a request hits in a cache and the cache is not going 659 * to respond. This is used by the crossbar to coordinate 660 * responses for cache maintenance operations. 661 */ 662 void setSatisfied() 663 { 664 assert(cmd.isClean()); 665 assert(!flags.isSet(SATISFIED)); 666 flags.set(SATISFIED); 667 } 668 bool satisfied() const { return flags.isSet(SATISFIED); } 669 670 void setSuppressFuncError() { flags.set(SUPPRESS_FUNC_ERROR); } 671 bool suppressFuncError() const { return flags.isSet(SUPPRESS_FUNC_ERROR); } 672 void setBlockCached() { flags.set(BLOCK_CACHED); } 673 bool isBlockCached() const { return flags.isSet(BLOCK_CACHED); } 674 void clearBlockCached() { flags.clear(BLOCK_CACHED); } 675 676 /** 677 * QoS Value getter 678 * Returns 0 if QoS value was never set (constructor default). 679 * 680 * @return QoS priority value of the packet 681 */ 682 inline uint8_t qosValue() const { return _qosValue; } 683 684 /** 685 * QoS Value setter 686 * Interface for setting QoS priority value of the packet. 687 * 688 * @param qos_value QoS priority value 689 */ 690 inline void qosValue(const uint8_t qos_value) 691 { _qosValue = qos_value; } 692 693 inline MasterID masterId() const { return req->masterId(); } 694 695 // Network error conditions... encapsulate them as methods since 696 // their encoding keeps changing (from result field to command 697 // field, etc.) 698 void 699 setBadAddress() 700 { 701 assert(isResponse()); 702 cmd = MemCmd::BadAddressError; 703 } 704 705 void copyError(Packet *pkt) { assert(pkt->isError()); cmd = pkt->cmd; } 706 707 Addr getAddr() const { assert(flags.isSet(VALID_ADDR)); return addr; } 708 /** 709 * Update the address of this packet mid-transaction. This is used 710 * by the address mapper to change an already set address to a new 711 * one based on the system configuration. It is intended to remap 712 * an existing address, so it asserts that the current address is 713 * valid. 714 */ 715 void setAddr(Addr _addr) { assert(flags.isSet(VALID_ADDR)); addr = _addr; } 716 717 unsigned getSize() const { assert(flags.isSet(VALID_SIZE)); return size; } 718 719 Addr getOffset(unsigned int blk_size) const 720 { 721 return getAddr() & Addr(blk_size - 1); 722 } 723 724 Addr getBlockAddr(unsigned int blk_size) const 725 { 726 return getAddr() & ~(Addr(blk_size - 1)); 727 } 728 729 bool isSecure() const 730 { 731 assert(flags.isSet(VALID_ADDR)); 732 return _isSecure; 733 } 734 735 /** 736 * Accessor function to atomic op. 737 */ 738 AtomicOpFunctor *getAtomicOp() const { return req->getAtomicOpFunctor(); } 739 bool isAtomicOp() const { return req->isAtomic(); } 740 741 /** 742 * It has been determined that the SC packet should successfully update 743 * memory. Therefore, convert this SC packet to a normal write. 744 */ 745 void 746 convertScToWrite() 747 { 748 assert(isLLSC()); 749 assert(isWrite()); 750 cmd = MemCmd::WriteReq; 751 } 752 753 /** 754 * When ruby is in use, Ruby will monitor the cache line and the 755 * phys memory should treat LL ops as normal reads. 756 */ 757 void 758 convertLlToRead() 759 { 760 assert(isLLSC()); 761 assert(isRead()); 762 cmd = MemCmd::ReadReq; 763 } 764 765 /** 766 * Constructor. Note that a Request object must be constructed 767 * first, but the Requests's physical address and size fields need 768 * not be valid. The command must be supplied. 769 */ 770 Packet(const RequestPtr &_req, MemCmd _cmd) 771 : cmd(_cmd), id((PacketId)_req.get()), req(_req), 772 data(nullptr), addr(0), _isSecure(false), size(0), 773 _qosValue(0), headerDelay(0), snoopDelay(0), 774 payloadDelay(0), senderState(NULL) 775 { 776 if (req->hasPaddr()) { 777 addr = req->getPaddr(); 778 flags.set(VALID_ADDR); 779 _isSecure = req->isSecure(); 780 } 781 if (req->hasSize()) { 782 size = req->getSize(); 783 flags.set(VALID_SIZE); 784 } 785 } 786 787 /** 788 * Alternate constructor if you are trying to create a packet with 789 * a request that is for a whole block, not the address from the 790 * req. this allows for overriding the size/addr of the req. 791 */ 792 Packet(const RequestPtr &_req, MemCmd _cmd, int _blkSize, PacketId _id = 0) 793 : cmd(_cmd), id(_id ? _id : (PacketId)_req.get()), req(_req), 794 data(nullptr), addr(0), _isSecure(false), 795 _qosValue(0), headerDelay(0), 796 snoopDelay(0), payloadDelay(0), senderState(NULL) 797 { 798 if (req->hasPaddr()) { 799 addr = req->getPaddr() & ~(_blkSize - 1); 800 flags.set(VALID_ADDR); 801 _isSecure = req->isSecure(); 802 } 803 size = _blkSize; 804 flags.set(VALID_SIZE); 805 } 806 807 /** 808 * Alternate constructor for copying a packet. Copy all fields 809 * *except* if the original packet's data was dynamic, don't copy 810 * that, as we can't guarantee that the new packet's lifetime is 811 * less than that of the original packet. In this case the new 812 * packet should allocate its own data. 813 */ 814 Packet(const PacketPtr pkt, bool clear_flags, bool alloc_data) 815 : cmd(pkt->cmd), id(pkt->id), req(pkt->req), 816 data(nullptr), 817 addr(pkt->addr), _isSecure(pkt->_isSecure), size(pkt->size), 818 bytesValid(pkt->bytesValid), 819 _qosValue(pkt->qosValue()), 820 headerDelay(pkt->headerDelay), 821 snoopDelay(0), 822 payloadDelay(pkt->payloadDelay), 823 senderState(pkt->senderState) 824 { 825 if (!clear_flags) 826 flags.set(pkt->flags & COPY_FLAGS); 827 828 flags.set(pkt->flags & (VALID_ADDR|VALID_SIZE)); 829 830 // should we allocate space for data, or not, the express 831 // snoops do not need to carry any data as they only serve to 832 // co-ordinate state changes 833 if (alloc_data) { 834 // even if asked to allocate data, if the original packet 835 // holds static data, then the sender will not be doing 836 // any memcpy on receiving the response, thus we simply 837 // carry the pointer forward 838 if (pkt->flags.isSet(STATIC_DATA)) { 839 data = pkt->data; 840 flags.set(STATIC_DATA); 841 } else { 842 allocate(); 843 } 844 } 845 } 846 847 /** 848 * Generate the appropriate read MemCmd based on the Request flags. 849 */ 850 static MemCmd 851 makeReadCmd(const RequestPtr &req) 852 { 853 if (req->isLLSC()) 854 return MemCmd::LoadLockedReq; 855 else if (req->isPrefetch()) 856 return MemCmd::SoftPFReq; 857 else 858 return MemCmd::ReadReq; 859 } 860 861 /** 862 * Generate the appropriate write MemCmd based on the Request flags. 863 */ 864 static MemCmd 865 makeWriteCmd(const RequestPtr &req) 866 { 867 if (req->isLLSC()) 868 return MemCmd::StoreCondReq; 869 else if (req->isSwap() || req->isAtomic()) 870 return MemCmd::SwapReq; 871 else if (req->isCacheInvalidate()) { 872 return req->isCacheClean() ? MemCmd::CleanInvalidReq : 873 MemCmd::InvalidateReq; 874 } else if (req->isCacheClean()) { 875 return MemCmd::CleanSharedReq; 876 } else 877 return MemCmd::WriteReq; 878 } 879 880 /** 881 * Constructor-like methods that return Packets based on Request objects. 882 * Fine-tune the MemCmd type if it's not a vanilla read or write. 883 */ 884 static PacketPtr 885 createRead(const RequestPtr &req) 886 { 887 return new Packet(req, makeReadCmd(req)); 888 } 889 890 static PacketPtr 891 createWrite(const RequestPtr &req) 892 { 893 return new Packet(req, makeWriteCmd(req)); 894 } 895 896 /** 897 * clean up packet variables 898 */ 899 ~Packet() 900 { 901 deleteData(); 902 } 903 904 /** 905 * Take a request packet and modify it in place to be suitable for 906 * returning as a response to that request. 907 */ 908 void 909 makeResponse() 910 { 911 assert(needsResponse()); 912 assert(isRequest()); 913 cmd = cmd.responseCommand(); 914 915 // responses are never express, even if the snoop that 916 // triggered them was 917 flags.clear(EXPRESS_SNOOP); 918 } 919 920 void 921 makeAtomicResponse() 922 { 923 makeResponse(); 924 } 925 926 void 927 makeTimingResponse() 928 { 929 makeResponse(); 930 } 931 932 void 933 setFunctionalResponseStatus(bool success) 934 { 935 if (!success) { 936 if (isWrite()) { 937 cmd = MemCmd::FunctionalWriteError; 938 } else { 939 cmd = MemCmd::FunctionalReadError; 940 } 941 } 942 } 943 944 void 945 setSize(unsigned size) 946 { 947 assert(!flags.isSet(VALID_SIZE)); 948 949 this->size = size; 950 flags.set(VALID_SIZE); 951 } 952 953 954 public: 955 /** 956 * @{ 957 * @name Data accessor mehtods 958 */ 959 960 /** 961 * Set the data pointer to the following value that should not be 962 * freed. Static data allows us to do a single memcpy even if 963 * multiple packets are required to get from source to destination 964 * and back. In essence the pointer is set calling dataStatic on 965 * the original packet, and whenever this packet is copied and 966 * forwarded the same pointer is passed on. When a packet 967 * eventually reaches the destination holding the data, it is 968 * copied once into the location originally set. On the way back 969 * to the source, no copies are necessary. 970 */ 971 template <typename T> 972 void 973 dataStatic(T *p) 974 { 975 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 976 data = (PacketDataPtr)p; 977 flags.set(STATIC_DATA); 978 } 979 980 /** 981 * Set the data pointer to the following value that should not be 982 * freed. This version of the function allows the pointer passed 983 * to us to be const. To avoid issues down the line we cast the 984 * constness away, the alternative would be to keep both a const 985 * and non-const data pointer and cleverly choose between 986 * them. Note that this is only allowed for static data. 987 */ 988 template <typename T> 989 void 990 dataStaticConst(const T *p) 991 { 992 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 993 data = const_cast<PacketDataPtr>(p); 994 flags.set(STATIC_DATA); 995 } 996 997 /** 998 * Set the data pointer to a value that should have delete [] 999 * called on it. Dynamic data is local to this packet, and as the 1000 * packet travels from source to destination, forwarded packets 1001 * will allocate their own data. When a packet reaches the final 1002 * destination it will populate the dynamic data of that specific 1003 * packet, and on the way back towards the source, memcpy will be 1004 * invoked in every step where a new packet was created e.g. in 1005 * the caches. Ultimately when the response reaches the source a 1006 * final memcpy is needed to extract the data from the packet 1007 * before it is deallocated. 1008 */ 1009 template <typename T> 1010 void 1011 dataDynamic(T *p) 1012 { 1013 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 1014 data = (PacketDataPtr)p; 1015 flags.set(DYNAMIC_DATA); 1016 } 1017 1018 /** 1019 * get a pointer to the data ptr. 1020 */ 1021 template <typename T> 1022 T* 1023 getPtr() 1024 { 1025 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA)); 1026 return (T*)data; 1027 } 1028 1029 template <typename T> 1030 const T* 1031 getConstPtr() const 1032 { 1033 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA)); 1034 return (const T*)data; 1035 } 1036 1037 /** 1038 * Get the data in the packet byte swapped from big endian to 1039 * host endian. 1040 */ 1041 template <typename T> 1042 T getBE() const; 1043 1044 /** 1045 * Get the data in the packet byte swapped from little endian to 1046 * host endian. 1047 */ 1048 template <typename T> 1049 T getLE() const; 1050 1051 /** 1052 * Get the data in the packet byte swapped from the specified 1053 * endianness. 1054 */ 1055 template <typename T> 1056 T get(ByteOrder endian) const; 1057 1058 /** 1059 * Get the data in the packet byte swapped from guest to host 1060 * endian. 1061 */ 1062 template <typename T> 1063 T get() const; 1064 1065 /** Set the value in the data pointer to v as big endian. */ 1066 template <typename T> 1067 void setBE(T v); 1068 1069 /** Set the value in the data pointer to v as little endian. */ 1070 template <typename T> 1071 void setLE(T v); 1072 1073 /** 1074 * Set the value in the data pointer to v using the specified 1075 * endianness. 1076 */ 1077 template <typename T> 1078 void set(T v, ByteOrder endian); 1079 1080 /** Set the value in the data pointer to v as guest endian. */ 1081 template <typename T> 1082 void set(T v); 1083 1084 1085 /** 1086 * Get the data in the packet byte swapped from the specified 1087 * endianness and zero-extended to 64 bits. 1088 */ 1089 uint64_t getUintX(ByteOrder endian) const; 1090 1091 /** 1092 * Set the value in the word w after truncating it to the length 1093 * of the packet and then byteswapping it to the desired 1094 * endianness. 1095 */ 1096 void setUintX(uint64_t w, ByteOrder endian); 1097 1098 /** 1099 * Copy data into the packet from the provided pointer. 1100 */ 1101 void 1102 setData(const uint8_t *p) 1103 { 1104 // we should never be copying data onto itself, which means we 1105 // must idenfity packets with static data, as they carry the 1106 // same pointer from source to destination and back 1107 assert(p != getPtr<uint8_t>() || flags.isSet(STATIC_DATA)); 1108 1109 if (p != getPtr<uint8_t>()) 1110 // for packet with allocated dynamic data, we copy data from 1111 // one to the other, e.g. a forwarded response to a response 1112 std::memcpy(getPtr<uint8_t>(), p, getSize()); 1113 } 1114 1115 /** 1116 * Copy data into the packet from the provided block pointer, 1117 * which is aligned to the given block size. 1118 */ 1119 void 1120 setDataFromBlock(const uint8_t *blk_data, int blkSize) 1121 { 1122 setData(blk_data + getOffset(blkSize)); 1123 } 1124 1125 /** 1126 * Copy data from the packet to the memory at the provided pointer. 1127 * @param p Pointer to which data will be copied. 1128 */ 1129 void 1130 writeData(uint8_t *p) const 1131 { 1132 std::memcpy(p, getConstPtr<uint8_t>(), getSize()); 1133 } 1134 1135 /** 1136 * Copy data from the packet to the provided block pointer, which 1137 * is aligned to the given block size. 1138 * @param blk_data Pointer to block to which data will be copied. 1139 * @param blkSize Block size in bytes. 1140 */ 1141 void 1142 writeDataToBlock(uint8_t *blk_data, int blkSize) const 1143 { 1144 writeData(blk_data + getOffset(blkSize)); 1145 } 1146 1147 /** 1148 * delete the data pointed to in the data pointer. Ok to call to 1149 * matter how data was allocted. 1150 */ 1151 void 1152 deleteData() 1153 { 1154 if (flags.isSet(DYNAMIC_DATA)) 1155 delete [] data; 1156 1157 flags.clear(STATIC_DATA|DYNAMIC_DATA); 1158 data = NULL; 1159 } 1160 1161 /** Allocate memory for the packet. */ 1162 void 1163 allocate() 1164 { 1165 // if either this command or the response command has a data 1166 // payload, actually allocate space 1167 if (hasData() || hasRespData()) { 1168 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 1169 flags.set(DYNAMIC_DATA); 1170 data = new uint8_t[getSize()]; 1171 } 1172 } 1173 1174 /** @} */ 1175 1176 /** Get the data in the packet without byte swapping. */ 1177 template <typename T> 1178 T getRaw() const; 1179 1180 /** Set the value in the data pointer to v without byte swapping. */ 1181 template <typename T> 1182 void setRaw(T v); 1183 1184 public: 1185 /** 1186 * Check a functional request against a memory value stored in 1187 * another packet (i.e. an in-transit request or 1188 * response). Returns true if the current packet is a read, and 1189 * the other packet provides the data, which is then copied to the 1190 * current packet. If the current packet is a write, and the other 1191 * packet intersects this one, then we update the data 1192 * accordingly. 1193 */ 1194 bool 1195 trySatisfyFunctional(PacketPtr other) 1196 { 1197 // all packets that are carrying a payload should have a valid 1198 // data pointer 1199 return trySatisfyFunctional(other, other->getAddr(), other->isSecure(), 1200 other->getSize(), 1201 other->hasData() ? 1202 other->getPtr<uint8_t>() : NULL); 1203 } 1204 1205 /** 1206 * Does the request need to check for cached copies of the same block 1207 * in the memory hierarchy above. 1208 **/ 1209 bool 1210 mustCheckAbove() const 1211 { 1212 return cmd == MemCmd::HardPFReq || isEviction(); 1213 } 1214 1215 /** 1216 * Is this packet a clean eviction, including both actual clean 1217 * evict packets, but also clean writebacks. 1218 */ 1219 bool 1220 isCleanEviction() const 1221 { 1222 return cmd == MemCmd::CleanEvict || cmd == MemCmd::WritebackClean; 1223 } 1224 1225 /** 1226 * Check a functional request against a memory value represented 1227 * by a base/size pair and an associated data array. If the 1228 * current packet is a read, it may be satisfied by the memory 1229 * value. If the current packet is a write, it may update the 1230 * memory value. 1231 */ 1232 bool 1233 trySatisfyFunctional(Printable *obj, Addr base, bool is_secure, int size, 1234 uint8_t *_data); 1235 1236 /** 1237 * Push label for PrintReq (safe to call unconditionally). 1238 */ 1239 void 1240 pushLabel(const std::string &lbl) 1241 { 1242 if (isPrint()) 1243 safe_cast<PrintReqState*>(senderState)->pushLabel(lbl); 1244 } 1245 1246 /** 1247 * Pop label for PrintReq (safe to call unconditionally). 1248 */ 1249 void 1250 popLabel() 1251 { 1252 if (isPrint()) 1253 safe_cast<PrintReqState*>(senderState)->popLabel(); 1254 } 1255 1256 void print(std::ostream &o, int verbosity = 0, 1257 const std::string &prefix = "") const; 1258 1259 /** 1260 * A no-args wrapper of print(std::ostream...) 1261 * meant to be invoked from DPRINTFs 1262 * avoiding string overheads in fast mode 1263 * @return string with the request's type and start<->end addresses 1264 */ 1265 std::string print() const; 1266}; 1267 1268#endif //__MEM_PACKET_HH 1269