packet.hh revision 13732:43e7199f511f
1/* 2 * Copyright (c) 2012-2019 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 "config/the_isa.hh" 67#include "mem/request.hh" 68#include "sim/core.hh" 69 70class Packet; 71typedef Packet *PacketPtr; 72typedef uint8_t* PacketDataPtr; 73typedef std::list<PacketPtr> PacketList; 74typedef uint64_t PacketId; 75 76class MemCmd 77{ 78 friend class Packet; 79 80 public: 81 /** 82 * List of all commands associated with a packet. 83 */ 84 enum Command 85 { 86 InvalidCmd, 87 ReadReq, 88 ReadResp, 89 ReadRespWithInvalidate, 90 WriteReq, 91 WriteResp, 92 WritebackDirty, 93 WritebackClean, 94 WriteClean, // writes dirty data below without evicting 95 CleanEvict, 96 SoftPFReq, 97 SoftPFExReq, 98 HardPFReq, 99 SoftPFResp, 100 HardPFResp, 101 WriteLineReq, 102 UpgradeReq, 103 SCUpgradeReq, // Special "weak" upgrade for StoreCond 104 UpgradeResp, 105 SCUpgradeFailReq, // Failed SCUpgradeReq in MSHR (never sent) 106 UpgradeFailResp, // Valid for SCUpgradeReq only 107 ReadExReq, 108 ReadExResp, 109 ReadCleanReq, 110 ReadSharedReq, 111 LoadLockedReq, 112 StoreCondReq, 113 StoreCondFailReq, // Failed StoreCondReq in MSHR (never sent) 114 StoreCondResp, 115 SwapReq, 116 SwapResp, 117 MessageReq, 118 MessageResp, 119 MemFenceReq, 120 MemFenceResp, 121 CleanSharedReq, 122 CleanSharedResp, 123 CleanInvalidReq, 124 CleanInvalidResp, 125 // Error responses 126 // @TODO these should be classified as responses rather than 127 // requests; coding them as requests initially for backwards 128 // compatibility 129 InvalidDestError, // packet dest field invalid 130 BadAddressError, // memory address invalid 131 FunctionalReadError, // unable to fulfill functional read 132 FunctionalWriteError, // unable to fulfill functional write 133 // Fake simulator-only commands 134 PrintReq, // Print state matching address 135 FlushReq, //request for a cache flush 136 InvalidateReq, // request for address to be invalidated 137 InvalidateResp, 138 NUM_MEM_CMDS 139 }; 140 141 private: 142 /** 143 * List of command attributes. 144 */ 145 enum Attribute 146 { 147 IsRead, //!< Data flows from responder to requester 148 IsWrite, //!< Data flows from requester to responder 149 IsUpgrade, 150 IsInvalidate, 151 IsClean, //!< Cleans any existing dirty blocks 152 NeedsWritable, //!< Requires writable copy to complete in-cache 153 IsRequest, //!< Issued by requester 154 IsResponse, //!< Issue by responder 155 NeedsResponse, //!< Requester needs response from target 156 IsEviction, 157 IsSWPrefetch, 158 IsHWPrefetch, 159 IsLlsc, //!< Alpha/MIPS LL or SC access 160 HasData, //!< There is an associated payload 161 IsError, //!< Error response 162 IsPrint, //!< Print state matching address (for debugging) 163 IsFlush, //!< Flush the address from caches 164 FromCache, //!< Request originated from a caching agent 165 NUM_COMMAND_ATTRIBUTES 166 }; 167 168 /** 169 * Structure that defines attributes and other data associated 170 * with a Command. 171 */ 172 struct CommandInfo 173 { 174 /// Set of attribute flags. 175 const std::bitset<NUM_COMMAND_ATTRIBUTES> attributes; 176 /// Corresponding response for requests; InvalidCmd if no 177 /// response is applicable. 178 const Command response; 179 /// String representation (for printing) 180 const std::string str; 181 }; 182 183 /// Array to map Command enum to associated info. 184 static const CommandInfo commandInfo[]; 185 186 private: 187 188 Command cmd; 189 190 bool 191 testCmdAttrib(MemCmd::Attribute attrib) const 192 { 193 return commandInfo[cmd].attributes[attrib] != 0; 194 } 195 196 public: 197 198 bool isRead() const { return testCmdAttrib(IsRead); } 199 bool isWrite() const { return testCmdAttrib(IsWrite); } 200 bool isUpgrade() const { return testCmdAttrib(IsUpgrade); } 201 bool isRequest() const { return testCmdAttrib(IsRequest); } 202 bool isResponse() const { return testCmdAttrib(IsResponse); } 203 bool needsWritable() const { return testCmdAttrib(NeedsWritable); } 204 bool needsResponse() const { return testCmdAttrib(NeedsResponse); } 205 bool isInvalidate() const { return testCmdAttrib(IsInvalidate); } 206 bool isEviction() const { return testCmdAttrib(IsEviction); } 207 bool isClean() const { return testCmdAttrib(IsClean); } 208 bool fromCache() const { return testCmdAttrib(FromCache); } 209 210 /** 211 * A writeback is an eviction that carries data. 212 */ 213 bool isWriteback() const { return testCmdAttrib(IsEviction) && 214 testCmdAttrib(HasData); } 215 216 /** 217 * Check if this particular packet type carries payload data. Note 218 * that this does not reflect if the data pointer of the packet is 219 * valid or not. 220 */ 221 bool hasData() const { return testCmdAttrib(HasData); } 222 bool isLLSC() const { return testCmdAttrib(IsLlsc); } 223 bool isSWPrefetch() const { return testCmdAttrib(IsSWPrefetch); } 224 bool isHWPrefetch() const { return testCmdAttrib(IsHWPrefetch); } 225 bool isPrefetch() const { return testCmdAttrib(IsSWPrefetch) || 226 testCmdAttrib(IsHWPrefetch); } 227 bool isError() const { return testCmdAttrib(IsError); } 228 bool isPrint() const { return testCmdAttrib(IsPrint); } 229 bool isFlush() const { return testCmdAttrib(IsFlush); } 230 231 Command 232 responseCommand() const 233 { 234 return commandInfo[cmd].response; 235 } 236 237 /// Return the string to a cmd given by idx. 238 const std::string &toString() const { return commandInfo[cmd].str; } 239 int toInt() const { return (int)cmd; } 240 241 MemCmd(Command _cmd) : cmd(_cmd) { } 242 MemCmd(int _cmd) : cmd((Command)_cmd) { } 243 MemCmd() : cmd(InvalidCmd) { } 244 245 bool operator==(MemCmd c2) const { return (cmd == c2.cmd); } 246 bool operator!=(MemCmd c2) const { return (cmd != c2.cmd); } 247}; 248 249/** 250 * A Packet is used to encapsulate a transfer between two objects in 251 * the memory system (e.g., the L1 and L2 cache). (In contrast, a 252 * single Request travels all the way from the requester to the 253 * ultimate destination and back, possibly being conveyed by several 254 * different Packets along the way.) 255 */ 256class Packet : public Printable 257{ 258 public: 259 typedef uint32_t FlagsType; 260 typedef ::Flags<FlagsType> Flags; 261 262 private: 263 264 enum : FlagsType { 265 // Flags to transfer across when copying a packet 266 COPY_FLAGS = 0x0000003F, 267 268 // Flags that are used to create reponse packets 269 RESPONDER_FLAGS = 0x00000009, 270 271 // Does this packet have sharers (which means it should not be 272 // considered writable) or not. See setHasSharers below. 273 HAS_SHARERS = 0x00000001, 274 275 // Special control flags 276 /// Special timing-mode atomic snoop for multi-level coherence. 277 EXPRESS_SNOOP = 0x00000002, 278 279 /// Allow a responding cache to inform the cache hierarchy 280 /// that it had a writable copy before responding. See 281 /// setResponderHadWritable below. 282 RESPONDER_HAD_WRITABLE = 0x00000004, 283 284 // Snoop co-ordination flag to indicate that a cache is 285 // responding to a snoop. See setCacheResponding below. 286 CACHE_RESPONDING = 0x00000008, 287 288 // The writeback/writeclean should be propagated further 289 // downstream by the receiver 290 WRITE_THROUGH = 0x00000010, 291 292 // Response co-ordination flag for cache maintenance 293 // operations 294 SATISFIED = 0x00000020, 295 296 /// Are the 'addr' and 'size' fields valid? 297 VALID_ADDR = 0x00000100, 298 VALID_SIZE = 0x00000200, 299 300 /// Is the data pointer set to a value that shouldn't be freed 301 /// when the packet is destroyed? 302 STATIC_DATA = 0x00001000, 303 /// The data pointer points to a value that should be freed when 304 /// the packet is destroyed. The pointer is assumed to be pointing 305 /// to an array, and delete [] is consequently called 306 DYNAMIC_DATA = 0x00002000, 307 308 /// suppress the error if this packet encounters a functional 309 /// access failure. 310 SUPPRESS_FUNC_ERROR = 0x00008000, 311 312 // Signal block present to squash prefetch and cache evict packets 313 // through express snoop flag 314 BLOCK_CACHED = 0x00010000 315 }; 316 317 Flags flags; 318 319 public: 320 typedef MemCmd::Command Command; 321 322 /// The command field of the packet. 323 MemCmd cmd; 324 325 const PacketId id; 326 327 /// A pointer to the original request. 328 RequestPtr req; 329 330 private: 331 /** 332 * A pointer to the data being transferred. It can be different 333 * sizes at each level of the hierarchy so it belongs to the 334 * packet, not request. This may or may not be populated when a 335 * responder receives the packet. If not populated memory should 336 * be allocated. 337 */ 338 PacketDataPtr data; 339 340 /// The address of the request. This address could be virtual or 341 /// physical, depending on the system configuration. 342 Addr addr; 343 344 /// True if the request targets the secure memory space. 345 bool _isSecure; 346 347 /// The size of the request or transfer. 348 unsigned size; 349 350 /** 351 * Track the bytes found that satisfy a functional read. 352 */ 353 std::vector<bool> bytesValid; 354 355 // Quality of Service priority value 356 uint8_t _qosValue; 357 358 public: 359 360 /** 361 * The extra delay from seeing the packet until the header is 362 * transmitted. This delay is used to communicate the crossbar 363 * forwarding latency to the neighbouring object (e.g. a cache) 364 * that actually makes the packet wait. As the delay is relative, 365 * a 32-bit unsigned should be sufficient. 366 */ 367 uint32_t headerDelay; 368 369 /** 370 * Keep track of the extra delay incurred by snooping upwards 371 * before sending a request down the memory system. This is used 372 * by the coherent crossbar to account for the additional request 373 * delay. 374 */ 375 uint32_t snoopDelay; 376 377 /** 378 * The extra pipelining delay from seeing the packet until the end of 379 * payload is transmitted by the component that provided it (if 380 * any). This includes the header delay. Similar to the header 381 * delay, this is used to make up for the fact that the 382 * crossbar does not make the packet wait. As the delay is 383 * relative, a 32-bit unsigned should be sufficient. 384 */ 385 uint32_t payloadDelay; 386 387 /** 388 * A virtual base opaque structure used to hold state associated 389 * with the packet (e.g., an MSHR), specific to a MemObject that 390 * sees the packet. A pointer to this state is returned in the 391 * packet's response so that the MemObject in question can quickly 392 * look up the state needed to process it. A specific subclass 393 * would be derived from this to carry state specific to a 394 * particular sending device. 395 * 396 * As multiple MemObjects may add their SenderState throughout the 397 * memory system, the SenderStates create a stack, where a 398 * MemObject can add a new Senderstate, as long as the 399 * predecessing SenderState is restored when the response comes 400 * back. For this reason, the predecessor should always be 401 * populated with the current SenderState of a packet before 402 * modifying the senderState field in the request packet. 403 */ 404 struct SenderState 405 { 406 SenderState* predecessor; 407 SenderState() : predecessor(NULL) {} 408 virtual ~SenderState() {} 409 }; 410 411 /** 412 * Object used to maintain state of a PrintReq. The senderState 413 * field of a PrintReq should always be of this type. 414 */ 415 class PrintReqState : public SenderState 416 { 417 private: 418 /** 419 * An entry in the label stack. 420 */ 421 struct LabelStackEntry 422 { 423 const std::string label; 424 std::string *prefix; 425 bool labelPrinted; 426 LabelStackEntry(const std::string &_label, std::string *_prefix); 427 }; 428 429 typedef std::list<LabelStackEntry> LabelStack; 430 LabelStack labelStack; 431 432 std::string *curPrefixPtr; 433 434 public: 435 std::ostream &os; 436 const int verbosity; 437 438 PrintReqState(std::ostream &os, int verbosity = 0); 439 ~PrintReqState(); 440 441 /** 442 * Returns the current line prefix. 443 */ 444 const std::string &curPrefix() { return *curPrefixPtr; } 445 446 /** 447 * Push a label onto the label stack, and prepend the given 448 * prefix string onto the current prefix. Labels will only be 449 * printed if an object within the label's scope is printed. 450 */ 451 void pushLabel(const std::string &lbl, 452 const std::string &prefix = " "); 453 454 /** 455 * Pop a label off the label stack. 456 */ 457 void popLabel(); 458 459 /** 460 * Print all of the pending unprinted labels on the 461 * stack. Called by printObj(), so normally not called by 462 * users unless bypassing printObj(). 463 */ 464 void printLabels(); 465 466 /** 467 * Print a Printable object to os, because it matched the 468 * address on a PrintReq. 469 */ 470 void printObj(Printable *obj); 471 }; 472 473 /** 474 * This packet's sender state. Devices should use dynamic_cast<> 475 * to cast to the state appropriate to the sender. The intent of 476 * this variable is to allow a device to attach extra information 477 * to a request. A response packet must return the sender state 478 * that was attached to the original request (even if a new packet 479 * is created). 480 */ 481 SenderState *senderState; 482 483 /** 484 * Push a new sender state to the packet and make the current 485 * sender state the predecessor of the new one. This should be 486 * prefered over direct manipulation of the senderState member 487 * variable. 488 * 489 * @param sender_state SenderState to push at the top of the stack 490 */ 491 void pushSenderState(SenderState *sender_state); 492 493 /** 494 * Pop the top of the state stack and return a pointer to it. This 495 * assumes the current sender state is not NULL. This should be 496 * preferred over direct manipulation of the senderState member 497 * variable. 498 * 499 * @return The current top of the stack 500 */ 501 SenderState *popSenderState(); 502 503 /** 504 * Go through the sender state stack and return the first instance 505 * that is of type T (as determined by a dynamic_cast). If there 506 * is no sender state of type T, NULL is returned. 507 * 508 * @return The topmost state of type T 509 */ 510 template <typename T> 511 T * findNextSenderState() const 512 { 513 T *t = NULL; 514 SenderState* sender_state = senderState; 515 while (t == NULL && sender_state != NULL) { 516 t = dynamic_cast<T*>(sender_state); 517 sender_state = sender_state->predecessor; 518 } 519 return t; 520 } 521 522 /// Return the string name of the cmd field (for debugging and 523 /// tracing). 524 const std::string &cmdString() const { return cmd.toString(); } 525 526 /// Return the index of this command. 527 inline int cmdToIndex() const { return cmd.toInt(); } 528 529 bool isRead() const { return cmd.isRead(); } 530 bool isWrite() const { return cmd.isWrite(); } 531 bool isUpgrade() const { return cmd.isUpgrade(); } 532 bool isRequest() const { return cmd.isRequest(); } 533 bool isResponse() const { return cmd.isResponse(); } 534 bool needsWritable() const 535 { 536 // we should never check if a response needsWritable, the 537 // request has this flag, and for a response we should rather 538 // look at the hasSharers flag (if not set, the response is to 539 // be considered writable) 540 assert(isRequest()); 541 return cmd.needsWritable(); 542 } 543 bool needsResponse() const { return cmd.needsResponse(); } 544 bool isInvalidate() const { return cmd.isInvalidate(); } 545 bool isEviction() const { return cmd.isEviction(); } 546 bool isClean() const { return cmd.isClean(); } 547 bool fromCache() const { return cmd.fromCache(); } 548 bool isWriteback() const { return cmd.isWriteback(); } 549 bool hasData() const { return cmd.hasData(); } 550 bool hasRespData() const 551 { 552 MemCmd resp_cmd = cmd.responseCommand(); 553 return resp_cmd.hasData(); 554 } 555 bool isLLSC() const { return cmd.isLLSC(); } 556 bool isError() const { return cmd.isError(); } 557 bool isPrint() const { return cmd.isPrint(); } 558 bool isFlush() const { return cmd.isFlush(); } 559 560 bool isWholeLineWrite(unsigned blk_size) 561 { 562 return (cmd == MemCmd::WriteReq || cmd == MemCmd::WriteLineReq) && 563 getOffset(blk_size) == 0 && getSize() == blk_size; 564 } 565 566 //@{ 567 /// Snoop flags 568 /** 569 * Set the cacheResponding flag. This is used by the caches to 570 * signal another cache that they are responding to a request. A 571 * cache will only respond to snoops if it has the line in either 572 * Modified or Owned state. Note that on snoop hits we always pass 573 * the line as Modified and never Owned. In the case of an Owned 574 * line we proceed to invalidate all other copies. 575 * 576 * On a cache fill (see Cache::handleFill), we check hasSharers 577 * first, ignoring the cacheResponding flag if hasSharers is set. 578 * A line is consequently allocated as: 579 * 580 * hasSharers cacheResponding state 581 * true false Shared 582 * true true Shared 583 * false false Exclusive 584 * false true Modified 585 */ 586 void setCacheResponding() 587 { 588 assert(isRequest()); 589 assert(!flags.isSet(CACHE_RESPONDING)); 590 flags.set(CACHE_RESPONDING); 591 } 592 bool cacheResponding() const { return flags.isSet(CACHE_RESPONDING); } 593 /** 594 * On fills, the hasSharers flag is used by the caches in 595 * combination with the cacheResponding flag, as clarified 596 * above. If the hasSharers flag is not set, the packet is passing 597 * writable. Thus, a response from a memory passes the line as 598 * writable by default. 599 * 600 * The hasSharers flag is also used by upstream caches to inform a 601 * downstream cache that they have the block (by calling 602 * setHasSharers on snoop request packets that hit in upstream 603 * cachs tags or MSHRs). If the snoop packet has sharers, a 604 * downstream cache is prevented from passing a dirty line upwards 605 * if it was not explicitly asked for a writable copy. See 606 * Cache::satisfyCpuSideRequest. 607 * 608 * The hasSharers flag is also used on writebacks, in 609 * combination with the WritbackClean or WritebackDirty commands, 610 * to allocate the block downstream either as: 611 * 612 * command hasSharers state 613 * WritebackDirty false Modified 614 * WritebackDirty true Owned 615 * WritebackClean false Exclusive 616 * WritebackClean true Shared 617 */ 618 void setHasSharers() { flags.set(HAS_SHARERS); } 619 bool hasSharers() const { return flags.isSet(HAS_SHARERS); } 620 //@} 621 622 /** 623 * The express snoop flag is used for two purposes. Firstly, it is 624 * used to bypass flow control for normal (non-snoop) requests 625 * going downstream in the memory system. In cases where a cache 626 * is responding to a snoop from another cache (it had a dirty 627 * line), but the line is not writable (and there are possibly 628 * other copies), the express snoop flag is set by the downstream 629 * cache to invalidate all other copies in zero time. Secondly, 630 * the express snoop flag is also set to be able to distinguish 631 * snoop packets that came from a downstream cache, rather than 632 * snoop packets from neighbouring caches. 633 */ 634 void setExpressSnoop() { flags.set(EXPRESS_SNOOP); } 635 bool isExpressSnoop() const { return flags.isSet(EXPRESS_SNOOP); } 636 637 /** 638 * On responding to a snoop request (which only happens for 639 * Modified or Owned lines), make sure that we can transform an 640 * Owned response to a Modified one. If this flag is not set, the 641 * responding cache had the line in the Owned state, and there are 642 * possibly other Shared copies in the memory system. A downstream 643 * cache helps in orchestrating the invalidation of these copies 644 * by sending out the appropriate express snoops. 645 */ 646 void setResponderHadWritable() 647 { 648 assert(cacheResponding()); 649 assert(!responderHadWritable()); 650 flags.set(RESPONDER_HAD_WRITABLE); 651 } 652 bool responderHadWritable() const 653 { return flags.isSet(RESPONDER_HAD_WRITABLE); } 654 655 /** 656 * Copy the reponse flags from an input packet to this packet. The 657 * reponse flags determine whether a responder has been found and 658 * the state at which the block will be at the destination. 659 * 660 * @pkt The packet that we will copy flags from 661 */ 662 void copyResponderFlags(const PacketPtr pkt); 663 664 /** 665 * A writeback/writeclean cmd gets propagated further downstream 666 * by the receiver when the flag is set. 667 */ 668 void setWriteThrough() 669 { 670 assert(cmd.isWrite() && 671 (cmd.isEviction() || cmd == MemCmd::WriteClean)); 672 flags.set(WRITE_THROUGH); 673 } 674 void clearWriteThrough() { flags.clear(WRITE_THROUGH); } 675 bool writeThrough() const { return flags.isSet(WRITE_THROUGH); } 676 677 /** 678 * Set when a request hits in a cache and the cache is not going 679 * to respond. This is used by the crossbar to coordinate 680 * responses for cache maintenance operations. 681 */ 682 void setSatisfied() 683 { 684 assert(cmd.isClean()); 685 assert(!flags.isSet(SATISFIED)); 686 flags.set(SATISFIED); 687 } 688 bool satisfied() const { return flags.isSet(SATISFIED); } 689 690 void setSuppressFuncError() { flags.set(SUPPRESS_FUNC_ERROR); } 691 bool suppressFuncError() const { return flags.isSet(SUPPRESS_FUNC_ERROR); } 692 void setBlockCached() { flags.set(BLOCK_CACHED); } 693 bool isBlockCached() const { return flags.isSet(BLOCK_CACHED); } 694 void clearBlockCached() { flags.clear(BLOCK_CACHED); } 695 696 /** 697 * QoS Value getter 698 * Returns 0 if QoS value was never set (constructor default). 699 * 700 * @return QoS priority value of the packet 701 */ 702 inline uint8_t qosValue() const { return _qosValue; } 703 704 /** 705 * QoS Value setter 706 * Interface for setting QoS priority value of the packet. 707 * 708 * @param qos_value QoS priority value 709 */ 710 inline void qosValue(const uint8_t qos_value) 711 { _qosValue = qos_value; } 712 713 inline MasterID masterId() const { return req->masterId(); } 714 715 // Network error conditions... encapsulate them as methods since 716 // their encoding keeps changing (from result field to command 717 // field, etc.) 718 void 719 setBadAddress() 720 { 721 assert(isResponse()); 722 cmd = MemCmd::BadAddressError; 723 } 724 725 void copyError(Packet *pkt) { assert(pkt->isError()); cmd = pkt->cmd; } 726 727 Addr getAddr() const { assert(flags.isSet(VALID_ADDR)); return addr; } 728 /** 729 * Update the address of this packet mid-transaction. This is used 730 * by the address mapper to change an already set address to a new 731 * one based on the system configuration. It is intended to remap 732 * an existing address, so it asserts that the current address is 733 * valid. 734 */ 735 void setAddr(Addr _addr) { assert(flags.isSet(VALID_ADDR)); addr = _addr; } 736 737 unsigned getSize() const { assert(flags.isSet(VALID_SIZE)); return size; } 738 739 Addr getOffset(unsigned int blk_size) const 740 { 741 return getAddr() & Addr(blk_size - 1); 742 } 743 744 Addr getBlockAddr(unsigned int blk_size) const 745 { 746 return getAddr() & ~(Addr(blk_size - 1)); 747 } 748 749 bool isSecure() const 750 { 751 assert(flags.isSet(VALID_ADDR)); 752 return _isSecure; 753 } 754 755 /** 756 * Accessor function to atomic op. 757 */ 758 AtomicOpFunctor *getAtomicOp() const { return req->getAtomicOpFunctor(); } 759 bool isAtomicOp() const { return req->isAtomic(); } 760 761 /** 762 * It has been determined that the SC packet should successfully update 763 * memory. Therefore, convert this SC packet to a normal write. 764 */ 765 void 766 convertScToWrite() 767 { 768 assert(isLLSC()); 769 assert(isWrite()); 770 cmd = MemCmd::WriteReq; 771 } 772 773 /** 774 * When ruby is in use, Ruby will monitor the cache line and the 775 * phys memory should treat LL ops as normal reads. 776 */ 777 void 778 convertLlToRead() 779 { 780 assert(isLLSC()); 781 assert(isRead()); 782 cmd = MemCmd::ReadReq; 783 } 784 785 /** 786 * Constructor. Note that a Request object must be constructed 787 * first, but the Requests's physical address and size fields need 788 * not be valid. The command must be supplied. 789 */ 790 Packet(const RequestPtr &_req, MemCmd _cmd) 791 : cmd(_cmd), id((PacketId)_req.get()), req(_req), 792 data(nullptr), addr(0), _isSecure(false), size(0), 793 _qosValue(0), headerDelay(0), snoopDelay(0), 794 payloadDelay(0), senderState(NULL) 795 { 796 if (req->hasPaddr()) { 797 addr = req->getPaddr(); 798 flags.set(VALID_ADDR); 799 _isSecure = req->isSecure(); 800 } 801 if (req->hasSize()) { 802 size = req->getSize(); 803 flags.set(VALID_SIZE); 804 } 805 } 806 807 /** 808 * Alternate constructor if you are trying to create a packet with 809 * a request that is for a whole block, not the address from the 810 * req. this allows for overriding the size/addr of the req. 811 */ 812 Packet(const RequestPtr &_req, MemCmd _cmd, int _blkSize, PacketId _id = 0) 813 : cmd(_cmd), id(_id ? _id : (PacketId)_req.get()), req(_req), 814 data(nullptr), addr(0), _isSecure(false), 815 _qosValue(0), headerDelay(0), 816 snoopDelay(0), payloadDelay(0), senderState(NULL) 817 { 818 if (req->hasPaddr()) { 819 addr = req->getPaddr() & ~(_blkSize - 1); 820 flags.set(VALID_ADDR); 821 _isSecure = req->isSecure(); 822 } 823 size = _blkSize; 824 flags.set(VALID_SIZE); 825 } 826 827 /** 828 * Alternate constructor for copying a packet. Copy all fields 829 * *except* if the original packet's data was dynamic, don't copy 830 * that, as we can't guarantee that the new packet's lifetime is 831 * less than that of the original packet. In this case the new 832 * packet should allocate its own data. 833 */ 834 Packet(const PacketPtr pkt, bool clear_flags, bool alloc_data) 835 : cmd(pkt->cmd), id(pkt->id), req(pkt->req), 836 data(nullptr), 837 addr(pkt->addr), _isSecure(pkt->_isSecure), size(pkt->size), 838 bytesValid(pkt->bytesValid), 839 _qosValue(pkt->qosValue()), 840 headerDelay(pkt->headerDelay), 841 snoopDelay(0), 842 payloadDelay(pkt->payloadDelay), 843 senderState(pkt->senderState) 844 { 845 if (!clear_flags) 846 flags.set(pkt->flags & COPY_FLAGS); 847 848 flags.set(pkt->flags & (VALID_ADDR|VALID_SIZE)); 849 850 // should we allocate space for data, or not, the express 851 // snoops do not need to carry any data as they only serve to 852 // co-ordinate state changes 853 if (alloc_data) { 854 // even if asked to allocate data, if the original packet 855 // holds static data, then the sender will not be doing 856 // any memcpy on receiving the response, thus we simply 857 // carry the pointer forward 858 if (pkt->flags.isSet(STATIC_DATA)) { 859 data = pkt->data; 860 flags.set(STATIC_DATA); 861 } else { 862 allocate(); 863 } 864 } 865 } 866 867 /** 868 * Generate the appropriate read MemCmd based on the Request flags. 869 */ 870 static MemCmd 871 makeReadCmd(const RequestPtr &req) 872 { 873 if (req->isLLSC()) 874 return MemCmd::LoadLockedReq; 875 else if (req->isPrefetchEx()) 876 return MemCmd::SoftPFExReq; 877 else if (req->isPrefetch()) 878 return MemCmd::SoftPFReq; 879 else 880 return MemCmd::ReadReq; 881 } 882 883 /** 884 * Generate the appropriate write MemCmd based on the Request flags. 885 */ 886 static MemCmd 887 makeWriteCmd(const RequestPtr &req) 888 { 889 if (req->isLLSC()) 890 return MemCmd::StoreCondReq; 891 else if (req->isSwap() || req->isAtomic()) 892 return MemCmd::SwapReq; 893 else if (req->isCacheInvalidate()) { 894 return req->isCacheClean() ? MemCmd::CleanInvalidReq : 895 MemCmd::InvalidateReq; 896 } else if (req->isCacheClean()) { 897 return MemCmd::CleanSharedReq; 898 } else 899 return MemCmd::WriteReq; 900 } 901 902 /** 903 * Constructor-like methods that return Packets based on Request objects. 904 * Fine-tune the MemCmd type if it's not a vanilla read or write. 905 */ 906 static PacketPtr 907 createRead(const RequestPtr &req) 908 { 909 return new Packet(req, makeReadCmd(req)); 910 } 911 912 static PacketPtr 913 createWrite(const RequestPtr &req) 914 { 915 return new Packet(req, makeWriteCmd(req)); 916 } 917 918 /** 919 * clean up packet variables 920 */ 921 ~Packet() 922 { 923 deleteData(); 924 } 925 926 /** 927 * Take a request packet and modify it in place to be suitable for 928 * returning as a response to that request. 929 */ 930 void 931 makeResponse() 932 { 933 assert(needsResponse()); 934 assert(isRequest()); 935 cmd = cmd.responseCommand(); 936 937 // responses are never express, even if the snoop that 938 // triggered them was 939 flags.clear(EXPRESS_SNOOP); 940 } 941 942 void 943 makeAtomicResponse() 944 { 945 makeResponse(); 946 } 947 948 void 949 makeTimingResponse() 950 { 951 makeResponse(); 952 } 953 954 void 955 setFunctionalResponseStatus(bool success) 956 { 957 if (!success) { 958 if (isWrite()) { 959 cmd = MemCmd::FunctionalWriteError; 960 } else { 961 cmd = MemCmd::FunctionalReadError; 962 } 963 } 964 } 965 966 void 967 setSize(unsigned size) 968 { 969 assert(!flags.isSet(VALID_SIZE)); 970 971 this->size = size; 972 flags.set(VALID_SIZE); 973 } 974 975 976 public: 977 /** 978 * @{ 979 * @name Data accessor mehtods 980 */ 981 982 /** 983 * Set the data pointer to the following value that should not be 984 * freed. Static data allows us to do a single memcpy even if 985 * multiple packets are required to get from source to destination 986 * and back. In essence the pointer is set calling dataStatic on 987 * the original packet, and whenever this packet is copied and 988 * forwarded the same pointer is passed on. When a packet 989 * eventually reaches the destination holding the data, it is 990 * copied once into the location originally set. On the way back 991 * to the source, no copies are necessary. 992 */ 993 template <typename T> 994 void 995 dataStatic(T *p) 996 { 997 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 998 data = (PacketDataPtr)p; 999 flags.set(STATIC_DATA); 1000 } 1001 1002 /** 1003 * Set the data pointer to the following value that should not be 1004 * freed. This version of the function allows the pointer passed 1005 * to us to be const. To avoid issues down the line we cast the 1006 * constness away, the alternative would be to keep both a const 1007 * and non-const data pointer and cleverly choose between 1008 * them. Note that this is only allowed for static data. 1009 */ 1010 template <typename T> 1011 void 1012 dataStaticConst(const T *p) 1013 { 1014 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 1015 data = const_cast<PacketDataPtr>(p); 1016 flags.set(STATIC_DATA); 1017 } 1018 1019 /** 1020 * Set the data pointer to a value that should have delete [] 1021 * called on it. Dynamic data is local to this packet, and as the 1022 * packet travels from source to destination, forwarded packets 1023 * will allocate their own data. When a packet reaches the final 1024 * destination it will populate the dynamic data of that specific 1025 * packet, and on the way back towards the source, memcpy will be 1026 * invoked in every step where a new packet was created e.g. in 1027 * the caches. Ultimately when the response reaches the source a 1028 * final memcpy is needed to extract the data from the packet 1029 * before it is deallocated. 1030 */ 1031 template <typename T> 1032 void 1033 dataDynamic(T *p) 1034 { 1035 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 1036 data = (PacketDataPtr)p; 1037 flags.set(DYNAMIC_DATA); 1038 } 1039 1040 /** 1041 * get a pointer to the data ptr. 1042 */ 1043 template <typename T> 1044 T* 1045 getPtr() 1046 { 1047 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA)); 1048 return (T*)data; 1049 } 1050 1051 template <typename T> 1052 const T* 1053 getConstPtr() const 1054 { 1055 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA)); 1056 return (const T*)data; 1057 } 1058 1059 /** 1060 * Get the data in the packet byte swapped from big endian to 1061 * host endian. 1062 */ 1063 template <typename T> 1064 T getBE() const; 1065 1066 /** 1067 * Get the data in the packet byte swapped from little endian to 1068 * host endian. 1069 */ 1070 template <typename T> 1071 T getLE() const; 1072 1073 /** 1074 * Get the data in the packet byte swapped from the specified 1075 * endianness. 1076 */ 1077 template <typename T> 1078 T get(ByteOrder endian) const; 1079 1080#if THE_ISA != NULL_ISA 1081 /** 1082 * Get the data in the packet byte swapped from guest to host 1083 * endian. 1084 */ 1085 template <typename T> 1086 T get() const 1087 M5_DEPRECATED_MSG("The memory system should be ISA independent."); 1088#endif 1089 1090 /** Set the value in the data pointer to v as big endian. */ 1091 template <typename T> 1092 void setBE(T v); 1093 1094 /** Set the value in the data pointer to v as little endian. */ 1095 template <typename T> 1096 void setLE(T v); 1097 1098 /** 1099 * Set the value in the data pointer to v using the specified 1100 * endianness. 1101 */ 1102 template <typename T> 1103 void set(T v, ByteOrder endian); 1104 1105#if THE_ISA != NULL_ISA 1106 /** Set the value in the data pointer to v as guest endian. */ 1107 template <typename T> 1108 void set(T v) 1109 M5_DEPRECATED_MSG("The memory system should be ISA independent."); 1110#endif 1111 1112 /** 1113 * Get the data in the packet byte swapped from the specified 1114 * endianness and zero-extended to 64 bits. 1115 */ 1116 uint64_t getUintX(ByteOrder endian) const; 1117 1118 /** 1119 * Set the value in the word w after truncating it to the length 1120 * of the packet and then byteswapping it to the desired 1121 * endianness. 1122 */ 1123 void setUintX(uint64_t w, ByteOrder endian); 1124 1125 /** 1126 * Copy data into the packet from the provided pointer. 1127 */ 1128 void 1129 setData(const uint8_t *p) 1130 { 1131 // we should never be copying data onto itself, which means we 1132 // must idenfity packets with static data, as they carry the 1133 // same pointer from source to destination and back 1134 assert(p != getPtr<uint8_t>() || flags.isSet(STATIC_DATA)); 1135 1136 if (p != getPtr<uint8_t>()) 1137 // for packet with allocated dynamic data, we copy data from 1138 // one to the other, e.g. a forwarded response to a response 1139 std::memcpy(getPtr<uint8_t>(), p, getSize()); 1140 } 1141 1142 /** 1143 * Copy data into the packet from the provided block pointer, 1144 * which is aligned to the given block size. 1145 */ 1146 void 1147 setDataFromBlock(const uint8_t *blk_data, int blkSize) 1148 { 1149 setData(blk_data + getOffset(blkSize)); 1150 } 1151 1152 /** 1153 * Copy data from the packet to the memory at the provided pointer. 1154 * @param p Pointer to which data will be copied. 1155 */ 1156 void 1157 writeData(uint8_t *p) const 1158 { 1159 std::memcpy(p, getConstPtr<uint8_t>(), getSize()); 1160 } 1161 1162 /** 1163 * Copy data from the packet to the provided block pointer, which 1164 * is aligned to the given block size. 1165 * @param blk_data Pointer to block to which data will be copied. 1166 * @param blkSize Block size in bytes. 1167 */ 1168 void 1169 writeDataToBlock(uint8_t *blk_data, int blkSize) const 1170 { 1171 writeData(blk_data + getOffset(blkSize)); 1172 } 1173 1174 /** 1175 * delete the data pointed to in the data pointer. Ok to call to 1176 * matter how data was allocted. 1177 */ 1178 void 1179 deleteData() 1180 { 1181 if (flags.isSet(DYNAMIC_DATA)) 1182 delete [] data; 1183 1184 flags.clear(STATIC_DATA|DYNAMIC_DATA); 1185 data = NULL; 1186 } 1187 1188 /** Allocate memory for the packet. */ 1189 void 1190 allocate() 1191 { 1192 // if either this command or the response command has a data 1193 // payload, actually allocate space 1194 if (hasData() || hasRespData()) { 1195 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA)); 1196 flags.set(DYNAMIC_DATA); 1197 data = new uint8_t[getSize()]; 1198 } 1199 } 1200 1201 /** @} */ 1202 1203 /** Get the data in the packet without byte swapping. */ 1204 template <typename T> 1205 T getRaw() const; 1206 1207 /** Set the value in the data pointer to v without byte swapping. */ 1208 template <typename T> 1209 void setRaw(T v); 1210 1211 public: 1212 /** 1213 * Check a functional request against a memory value stored in 1214 * another packet (i.e. an in-transit request or 1215 * response). Returns true if the current packet is a read, and 1216 * the other packet provides the data, which is then copied to the 1217 * current packet. If the current packet is a write, and the other 1218 * packet intersects this one, then we update the data 1219 * accordingly. 1220 */ 1221 bool 1222 trySatisfyFunctional(PacketPtr other) 1223 { 1224 // all packets that are carrying a payload should have a valid 1225 // data pointer 1226 return trySatisfyFunctional(other, other->getAddr(), other->isSecure(), 1227 other->getSize(), 1228 other->hasData() ? 1229 other->getPtr<uint8_t>() : NULL); 1230 } 1231 1232 /** 1233 * Does the request need to check for cached copies of the same block 1234 * in the memory hierarchy above. 1235 **/ 1236 bool 1237 mustCheckAbove() const 1238 { 1239 return cmd == MemCmd::HardPFReq || isEviction(); 1240 } 1241 1242 /** 1243 * Is this packet a clean eviction, including both actual clean 1244 * evict packets, but also clean writebacks. 1245 */ 1246 bool 1247 isCleanEviction() const 1248 { 1249 return cmd == MemCmd::CleanEvict || cmd == MemCmd::WritebackClean; 1250 } 1251 1252 /** 1253 * Check a functional request against a memory value represented 1254 * by a base/size pair and an associated data array. If the 1255 * current packet is a read, it may be satisfied by the memory 1256 * value. If the current packet is a write, it may update the 1257 * memory value. 1258 */ 1259 bool 1260 trySatisfyFunctional(Printable *obj, Addr base, bool is_secure, int size, 1261 uint8_t *_data); 1262 1263 /** 1264 * Push label for PrintReq (safe to call unconditionally). 1265 */ 1266 void 1267 pushLabel(const std::string &lbl) 1268 { 1269 if (isPrint()) 1270 safe_cast<PrintReqState*>(senderState)->pushLabel(lbl); 1271 } 1272 1273 /** 1274 * Pop label for PrintReq (safe to call unconditionally). 1275 */ 1276 void 1277 popLabel() 1278 { 1279 if (isPrint()) 1280 safe_cast<PrintReqState*>(senderState)->popLabel(); 1281 } 1282 1283 void print(std::ostream &o, int verbosity = 0, 1284 const std::string &prefix = "") const; 1285 1286 /** 1287 * A no-args wrapper of print(std::ostream...) 1288 * meant to be invoked from DPRINTFs 1289 * avoiding string overheads in fast mode 1290 * @return string with the request's type and start<->end addresses 1291 */ 1292 std::string print() const; 1293}; 1294 1295#endif //__MEM_PACKET_HH 1296