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44 * Declaration of the Packet class.
47 #ifndef __MEM_PACKET_HH__
48 #define __MEM_PACKET_HH__
54 #include "base/addr_range.hh"
55 #include "base/cast.hh"
56 #include "base/compiler.hh"
57 #include "base/flags.hh"
58 #include "base/logging.hh"
59 #include "base/printable.hh"
60 #include "base/types.hh"
61 #include "mem/request.hh"
62 #include "sim/core.hh"
65 typedef Packet *PacketPtr;
66 typedef uint8_t* PacketDataPtr;
67 typedef std::list<PacketPtr> PacketList;
68 typedef uint64_t PacketId;
76 * List of all commands associated with a packet.
83 ReadRespWithInvalidate,
89 WriteClean, // writes dirty data below without evicting
98 SCUpgradeReq, // Special "weak" upgrade for StoreCond
100 SCUpgradeFailReq, // Failed SCUpgradeReq in MSHR (never sent)
101 UpgradeFailResp, // Valid for SCUpgradeReq only
108 StoreCondFailReq, // Failed StoreCondReq in MSHR (never sent)
112 // MessageReq and MessageResp are deprecated.
113 MemFenceReq = SwapResp + 3,
114 MemSyncReq, // memory synchronization request (e.g., cache invalidate)
115 MemSyncResp, // memory synchronization response
122 // @TODO these should be classified as responses rather than
123 // requests; coding them as requests initially for backwards
125 InvalidDestError, // packet dest field invalid
126 BadAddressError, // memory address invalid
127 FunctionalReadError, // unable to fulfill functional read
128 FunctionalWriteError, // unable to fulfill functional write
129 // Fake simulator-only commands
130 PrintReq, // Print state matching address
131 FlushReq, //request for a cache flush
132 InvalidateReq, // request for address to be invalidated
139 * List of command attributes.
143 IsRead, //!< Data flows from responder to requester
144 IsWrite, //!< Data flows from requester to responder
147 IsClean, //!< Cleans any existing dirty blocks
148 NeedsWritable, //!< Requires writable copy to complete in-cache
149 IsRequest, //!< Issued by requester
150 IsResponse, //!< Issue by responder
151 NeedsResponse, //!< Requester needs response from target
155 IsLlsc, //!< Alpha/MIPS LL or SC access
156 HasData, //!< There is an associated payload
157 IsError, //!< Error response
158 IsPrint, //!< Print state matching address (for debugging)
159 IsFlush, //!< Flush the address from caches
160 FromCache, //!< Request originated from a caching agent
161 NUM_COMMAND_ATTRIBUTES
165 * Structure that defines attributes and other data associated
170 /// Set of attribute flags.
171 const std::bitset<NUM_COMMAND_ATTRIBUTES> attributes;
172 /// Corresponding response for requests; InvalidCmd if no
173 /// response is applicable.
174 const Command response;
175 /// String representation (for printing)
176 const std::string str;
179 /// Array to map Command enum to associated info.
180 static const CommandInfo commandInfo[];
187 testCmdAttrib(MemCmd::Attribute attrib) const
189 return commandInfo[cmd].attributes[attrib] != 0;
194 bool isRead() const { return testCmdAttrib(IsRead); }
195 bool isWrite() const { return testCmdAttrib(IsWrite); }
196 bool isUpgrade() const { return testCmdAttrib(IsUpgrade); }
197 bool isRequest() const { return testCmdAttrib(IsRequest); }
198 bool isResponse() const { return testCmdAttrib(IsResponse); }
199 bool needsWritable() const { return testCmdAttrib(NeedsWritable); }
200 bool needsResponse() const { return testCmdAttrib(NeedsResponse); }
201 bool isInvalidate() const { return testCmdAttrib(IsInvalidate); }
202 bool isEviction() const { return testCmdAttrib(IsEviction); }
203 bool isClean() const { return testCmdAttrib(IsClean); }
204 bool fromCache() const { return testCmdAttrib(FromCache); }
207 * A writeback is an eviction that carries data.
209 bool isWriteback() const { return testCmdAttrib(IsEviction) &&
210 testCmdAttrib(HasData); }
213 * Check if this particular packet type carries payload data. Note
214 * that this does not reflect if the data pointer of the packet is
217 bool hasData() const { return testCmdAttrib(HasData); }
218 bool isLLSC() const { return testCmdAttrib(IsLlsc); }
219 bool isSWPrefetch() const { return testCmdAttrib(IsSWPrefetch); }
220 bool isHWPrefetch() const { return testCmdAttrib(IsHWPrefetch); }
221 bool isPrefetch() const { return testCmdAttrib(IsSWPrefetch) ||
222 testCmdAttrib(IsHWPrefetch); }
223 bool isError() const { return testCmdAttrib(IsError); }
224 bool isPrint() const { return testCmdAttrib(IsPrint); }
225 bool isFlush() const { return testCmdAttrib(IsFlush); }
228 responseCommand() const
230 return commandInfo[cmd].response;
233 /// Return the string to a cmd given by idx.
234 const std::string &toString() const { return commandInfo[cmd].str; }
235 int toInt() const { return (int)cmd; }
237 MemCmd(Command _cmd) : cmd(_cmd) { }
238 MemCmd(int _cmd) : cmd((Command)_cmd) { }
239 MemCmd() : cmd(InvalidCmd) { }
241 bool operator==(MemCmd c2) const { return (cmd == c2.cmd); }
242 bool operator!=(MemCmd c2) const { return (cmd != c2.cmd); }
246 * A Packet is used to encapsulate a transfer between two objects in
247 * the memory system (e.g., the L1 and L2 cache). (In contrast, a
248 * single Request travels all the way from the requester to the
249 * ultimate destination and back, possibly being conveyed by several
250 * different Packets along the way.)
252 class Packet : public Printable
255 typedef uint32_t FlagsType;
256 typedef ::Flags<FlagsType> Flags;
261 // Flags to transfer across when copying a packet
262 COPY_FLAGS = 0x0000003F,
264 // Flags that are used to create reponse packets
265 RESPONDER_FLAGS = 0x00000009,
267 // Does this packet have sharers (which means it should not be
268 // considered writable) or not. See setHasSharers below.
269 HAS_SHARERS = 0x00000001,
271 // Special control flags
272 /// Special timing-mode atomic snoop for multi-level coherence.
273 EXPRESS_SNOOP = 0x00000002,
275 /// Allow a responding cache to inform the cache hierarchy
276 /// that it had a writable copy before responding. See
277 /// setResponderHadWritable below.
278 RESPONDER_HAD_WRITABLE = 0x00000004,
280 // Snoop co-ordination flag to indicate that a cache is
281 // responding to a snoop. See setCacheResponding below.
282 CACHE_RESPONDING = 0x00000008,
284 // The writeback/writeclean should be propagated further
285 // downstream by the receiver
286 WRITE_THROUGH = 0x00000010,
288 // Response co-ordination flag for cache maintenance
290 SATISFIED = 0x00000020,
292 /// Are the 'addr' and 'size' fields valid?
293 VALID_ADDR = 0x00000100,
294 VALID_SIZE = 0x00000200,
296 /// Is the data pointer set to a value that shouldn't be freed
297 /// when the packet is destroyed?
298 STATIC_DATA = 0x00001000,
299 /// The data pointer points to a value that should be freed when
300 /// the packet is destroyed. The pointer is assumed to be pointing
301 /// to an array, and delete [] is consequently called
302 DYNAMIC_DATA = 0x00002000,
304 /// suppress the error if this packet encounters a functional
306 SUPPRESS_FUNC_ERROR = 0x00008000,
308 // Signal block present to squash prefetch and cache evict packets
309 // through express snoop flag
310 BLOCK_CACHED = 0x00010000
316 typedef MemCmd::Command Command;
318 /// The command field of the packet.
323 /// A pointer to the original request.
328 * A pointer to the data being transferred. It can be different
329 * sizes at each level of the hierarchy so it belongs to the
330 * packet, not request. This may or may not be populated when a
331 * responder receives the packet. If not populated memory should
336 /// The address of the request. This address could be virtual or
337 /// physical, depending on the system configuration.
340 /// True if the request targets the secure memory space.
343 /// The size of the request or transfer.
347 * Track the bytes found that satisfy a functional read.
349 std::vector<bool> bytesValid;
351 // Quality of Service priority value
357 * The extra delay from seeing the packet until the header is
358 * transmitted. This delay is used to communicate the crossbar
359 * forwarding latency to the neighbouring object (e.g. a cache)
360 * that actually makes the packet wait. As the delay is relative,
361 * a 32-bit unsigned should be sufficient.
363 uint32_t headerDelay;
366 * Keep track of the extra delay incurred by snooping upwards
367 * before sending a request down the memory system. This is used
368 * by the coherent crossbar to account for the additional request
374 * The extra pipelining delay from seeing the packet until the end of
375 * payload is transmitted by the component that provided it (if
376 * any). This includes the header delay. Similar to the header
377 * delay, this is used to make up for the fact that the
378 * crossbar does not make the packet wait. As the delay is
379 * relative, a 32-bit unsigned should be sufficient.
381 uint32_t payloadDelay;
384 * A virtual base opaque structure used to hold state associated
385 * with the packet (e.g., an MSHR), specific to a SimObject that
386 * sees the packet. A pointer to this state is returned in the
387 * packet's response so that the SimObject in question can quickly
388 * look up the state needed to process it. A specific subclass
389 * would be derived from this to carry state specific to a
390 * particular sending device.
392 * As multiple SimObjects may add their SenderState throughout the
393 * memory system, the SenderStates create a stack, where a
394 * SimObject can add a new Senderstate, as long as the
395 * predecessing SenderState is restored when the response comes
396 * back. For this reason, the predecessor should always be
397 * populated with the current SenderState of a packet before
398 * modifying the senderState field in the request packet.
402 SenderState* predecessor;
403 SenderState() : predecessor(NULL) {}
404 virtual ~SenderState() {}
408 * Object used to maintain state of a PrintReq. The senderState
409 * field of a PrintReq should always be of this type.
411 class PrintReqState : public SenderState
415 * An entry in the label stack.
417 struct LabelStackEntry
419 const std::string label;
422 LabelStackEntry(const std::string &_label, std::string *_prefix);
425 typedef std::list<LabelStackEntry> LabelStack;
426 LabelStack labelStack;
428 std::string *curPrefixPtr;
434 PrintReqState(std::ostream &os, int verbosity = 0);
438 * Returns the current line prefix.
440 const std::string &curPrefix() { return *curPrefixPtr; }
443 * Push a label onto the label stack, and prepend the given
444 * prefix string onto the current prefix. Labels will only be
445 * printed if an object within the label's scope is printed.
447 void pushLabel(const std::string &lbl,
448 const std::string &prefix = " ");
451 * Pop a label off the label stack.
456 * Print all of the pending unprinted labels on the
457 * stack. Called by printObj(), so normally not called by
458 * users unless bypassing printObj().
463 * Print a Printable object to os, because it matched the
464 * address on a PrintReq.
466 void printObj(Printable *obj);
470 * This packet's sender state. Devices should use dynamic_cast<>
471 * to cast to the state appropriate to the sender. The intent of
472 * this variable is to allow a device to attach extra information
473 * to a request. A response packet must return the sender state
474 * that was attached to the original request (even if a new packet
477 SenderState *senderState;
480 * Push a new sender state to the packet and make the current
481 * sender state the predecessor of the new one. This should be
482 * prefered over direct manipulation of the senderState member
485 * @param sender_state SenderState to push at the top of the stack
487 void pushSenderState(SenderState *sender_state);
490 * Pop the top of the state stack and return a pointer to it. This
491 * assumes the current sender state is not NULL. This should be
492 * preferred over direct manipulation of the senderState member
495 * @return The current top of the stack
497 SenderState *popSenderState();
500 * Go through the sender state stack and return the first instance
501 * that is of type T (as determined by a dynamic_cast). If there
502 * is no sender state of type T, NULL is returned.
504 * @return The topmost state of type T
506 template <typename T>
507 T * findNextSenderState() const
510 SenderState* sender_state = senderState;
511 while (t == NULL && sender_state != NULL) {
512 t = dynamic_cast<T*>(sender_state);
513 sender_state = sender_state->predecessor;
518 /// Return the string name of the cmd field (for debugging and
520 const std::string &cmdString() const { return cmd.toString(); }
522 /// Return the index of this command.
523 inline int cmdToIndex() const { return cmd.toInt(); }
525 bool isRead() const { return cmd.isRead(); }
526 bool isWrite() const { return cmd.isWrite(); }
527 bool isUpgrade() const { return cmd.isUpgrade(); }
528 bool isRequest() const { return cmd.isRequest(); }
529 bool isResponse() const { return cmd.isResponse(); }
530 bool needsWritable() const
532 // we should never check if a response needsWritable, the
533 // request has this flag, and for a response we should rather
534 // look at the hasSharers flag (if not set, the response is to
535 // be considered writable)
537 return cmd.needsWritable();
539 bool needsResponse() const { return cmd.needsResponse(); }
540 bool isInvalidate() const { return cmd.isInvalidate(); }
541 bool isEviction() const { return cmd.isEviction(); }
542 bool isClean() const { return cmd.isClean(); }
543 bool fromCache() const { return cmd.fromCache(); }
544 bool isWriteback() const { return cmd.isWriteback(); }
545 bool hasData() const { return cmd.hasData(); }
546 bool hasRespData() const
548 MemCmd resp_cmd = cmd.responseCommand();
549 return resp_cmd.hasData();
551 bool isLLSC() const { return cmd.isLLSC(); }
552 bool isError() const { return cmd.isError(); }
553 bool isPrint() const { return cmd.isPrint(); }
554 bool isFlush() const { return cmd.isFlush(); }
556 bool isWholeLineWrite(unsigned blk_size)
558 return (cmd == MemCmd::WriteReq || cmd == MemCmd::WriteLineReq) &&
559 getOffset(blk_size) == 0 && getSize() == blk_size;
565 * Set the cacheResponding flag. This is used by the caches to
566 * signal another cache that they are responding to a request. A
567 * cache will only respond to snoops if it has the line in either
568 * Modified or Owned state. Note that on snoop hits we always pass
569 * the line as Modified and never Owned. In the case of an Owned
570 * line we proceed to invalidate all other copies.
572 * On a cache fill (see Cache::handleFill), we check hasSharers
573 * first, ignoring the cacheResponding flag if hasSharers is set.
574 * A line is consequently allocated as:
576 * hasSharers cacheResponding state
579 * false false Exclusive
580 * false true Modified
582 void setCacheResponding()
585 assert(!flags.isSet(CACHE_RESPONDING));
586 flags.set(CACHE_RESPONDING);
588 bool cacheResponding() const { return flags.isSet(CACHE_RESPONDING); }
590 * On fills, the hasSharers flag is used by the caches in
591 * combination with the cacheResponding flag, as clarified
592 * above. If the hasSharers flag is not set, the packet is passing
593 * writable. Thus, a response from a memory passes the line as
594 * writable by default.
596 * The hasSharers flag is also used by upstream caches to inform a
597 * downstream cache that they have the block (by calling
598 * setHasSharers on snoop request packets that hit in upstream
599 * cachs tags or MSHRs). If the snoop packet has sharers, a
600 * downstream cache is prevented from passing a dirty line upwards
601 * if it was not explicitly asked for a writable copy. See
602 * Cache::satisfyCpuSideRequest.
604 * The hasSharers flag is also used on writebacks, in
605 * combination with the WritbackClean or WritebackDirty commands,
606 * to allocate the block downstream either as:
608 * command hasSharers state
609 * WritebackDirty false Modified
610 * WritebackDirty true Owned
611 * WritebackClean false Exclusive
612 * WritebackClean true Shared
614 void setHasSharers() { flags.set(HAS_SHARERS); }
615 bool hasSharers() const { return flags.isSet(HAS_SHARERS); }
619 * The express snoop flag is used for two purposes. Firstly, it is
620 * used to bypass flow control for normal (non-snoop) requests
621 * going downstream in the memory system. In cases where a cache
622 * is responding to a snoop from another cache (it had a dirty
623 * line), but the line is not writable (and there are possibly
624 * other copies), the express snoop flag is set by the downstream
625 * cache to invalidate all other copies in zero time. Secondly,
626 * the express snoop flag is also set to be able to distinguish
627 * snoop packets that came from a downstream cache, rather than
628 * snoop packets from neighbouring caches.
630 void setExpressSnoop() { flags.set(EXPRESS_SNOOP); }
631 bool isExpressSnoop() const { return flags.isSet(EXPRESS_SNOOP); }
634 * On responding to a snoop request (which only happens for
635 * Modified or Owned lines), make sure that we can transform an
636 * Owned response to a Modified one. If this flag is not set, the
637 * responding cache had the line in the Owned state, and there are
638 * possibly other Shared copies in the memory system. A downstream
639 * cache helps in orchestrating the invalidation of these copies
640 * by sending out the appropriate express snoops.
642 void setResponderHadWritable()
644 assert(cacheResponding());
645 assert(!responderHadWritable());
646 flags.set(RESPONDER_HAD_WRITABLE);
648 bool responderHadWritable() const
649 { return flags.isSet(RESPONDER_HAD_WRITABLE); }
652 * Copy the reponse flags from an input packet to this packet. The
653 * reponse flags determine whether a responder has been found and
654 * the state at which the block will be at the destination.
656 * @pkt The packet that we will copy flags from
658 void copyResponderFlags(const PacketPtr pkt);
661 * A writeback/writeclean cmd gets propagated further downstream
662 * by the receiver when the flag is set.
664 void setWriteThrough()
666 assert(cmd.isWrite() &&
667 (cmd.isEviction() || cmd == MemCmd::WriteClean));
668 flags.set(WRITE_THROUGH);
670 void clearWriteThrough() { flags.clear(WRITE_THROUGH); }
671 bool writeThrough() const { return flags.isSet(WRITE_THROUGH); }
674 * Set when a request hits in a cache and the cache is not going
675 * to respond. This is used by the crossbar to coordinate
676 * responses for cache maintenance operations.
680 assert(cmd.isClean());
681 assert(!flags.isSet(SATISFIED));
682 flags.set(SATISFIED);
684 bool satisfied() const { return flags.isSet(SATISFIED); }
686 void setSuppressFuncError() { flags.set(SUPPRESS_FUNC_ERROR); }
687 bool suppressFuncError() const { return flags.isSet(SUPPRESS_FUNC_ERROR); }
688 void setBlockCached() { flags.set(BLOCK_CACHED); }
689 bool isBlockCached() const { return flags.isSet(BLOCK_CACHED); }
690 void clearBlockCached() { flags.clear(BLOCK_CACHED); }
694 * Returns 0 if QoS value was never set (constructor default).
696 * @return QoS priority value of the packet
698 inline uint8_t qosValue() const { return _qosValue; }
702 * Interface for setting QoS priority value of the packet.
704 * @param qos_value QoS priority value
706 inline void qosValue(const uint8_t qos_value)
707 { _qosValue = qos_value; }
709 inline MasterID masterId() const { return req->masterId(); }
711 // Network error conditions... encapsulate them as methods since
712 // their encoding keeps changing (from result field to command
717 assert(isResponse());
718 cmd = MemCmd::BadAddressError;
721 void copyError(Packet *pkt) { assert(pkt->isError()); cmd = pkt->cmd; }
723 Addr getAddr() const { assert(flags.isSet(VALID_ADDR)); return addr; }
725 * Update the address of this packet mid-transaction. This is used
726 * by the address mapper to change an already set address to a new
727 * one based on the system configuration. It is intended to remap
728 * an existing address, so it asserts that the current address is
731 void setAddr(Addr _addr) { assert(flags.isSet(VALID_ADDR)); addr = _addr; }
733 unsigned getSize() const { assert(flags.isSet(VALID_SIZE)); return size; }
736 * Get address range to which this packet belongs.
738 * @return Address range of this packet.
740 AddrRange getAddrRange() const;
742 Addr getOffset(unsigned int blk_size) const
744 return getAddr() & Addr(blk_size - 1);
747 Addr getBlockAddr(unsigned int blk_size) const
749 return getAddr() & ~(Addr(blk_size - 1));
752 bool isSecure() const
754 assert(flags.isSet(VALID_ADDR));
759 * Accessor function to atomic op.
761 AtomicOpFunctor *getAtomicOp() const { return req->getAtomicOpFunctor(); }
762 bool isAtomicOp() const { return req->isAtomic(); }
765 * It has been determined that the SC packet should successfully update
766 * memory. Therefore, convert this SC packet to a normal write.
773 cmd = MemCmd::WriteReq;
777 * When ruby is in use, Ruby will monitor the cache line and the
778 * phys memory should treat LL ops as normal reads.
785 cmd = MemCmd::ReadReq;
789 * Constructor. Note that a Request object must be constructed
790 * first, but the Requests's physical address and size fields need
791 * not be valid. The command must be supplied.
793 Packet(const RequestPtr &_req, MemCmd _cmd)
794 : cmd(_cmd), id((PacketId)_req.get()), req(_req),
795 data(nullptr), addr(0), _isSecure(false), size(0),
796 _qosValue(0), headerDelay(0), snoopDelay(0),
797 payloadDelay(0), senderState(NULL)
799 if (req->hasPaddr()) {
800 addr = req->getPaddr();
801 flags.set(VALID_ADDR);
802 _isSecure = req->isSecure();
804 if (req->hasSize()) {
805 size = req->getSize();
806 flags.set(VALID_SIZE);
811 * Alternate constructor if you are trying to create a packet with
812 * a request that is for a whole block, not the address from the
813 * req. this allows for overriding the size/addr of the req.
815 Packet(const RequestPtr &_req, MemCmd _cmd, int _blkSize, PacketId _id = 0)
816 : cmd(_cmd), id(_id ? _id : (PacketId)_req.get()), req(_req),
817 data(nullptr), addr(0), _isSecure(false),
818 _qosValue(0), headerDelay(0),
819 snoopDelay(0), payloadDelay(0), senderState(NULL)
821 if (req->hasPaddr()) {
822 addr = req->getPaddr() & ~(_blkSize - 1);
823 flags.set(VALID_ADDR);
824 _isSecure = req->isSecure();
827 flags.set(VALID_SIZE);
831 * Alternate constructor for copying a packet. Copy all fields
832 * *except* if the original packet's data was dynamic, don't copy
833 * that, as we can't guarantee that the new packet's lifetime is
834 * less than that of the original packet. In this case the new
835 * packet should allocate its own data.
837 Packet(const PacketPtr pkt, bool clear_flags, bool alloc_data)
838 : cmd(pkt->cmd), id(pkt->id), req(pkt->req),
840 addr(pkt->addr), _isSecure(pkt->_isSecure), size(pkt->size),
841 bytesValid(pkt->bytesValid),
842 _qosValue(pkt->qosValue()),
843 headerDelay(pkt->headerDelay),
845 payloadDelay(pkt->payloadDelay),
846 senderState(pkt->senderState)
849 flags.set(pkt->flags & COPY_FLAGS);
851 flags.set(pkt->flags & (VALID_ADDR|VALID_SIZE));
853 // should we allocate space for data, or not, the express
854 // snoops do not need to carry any data as they only serve to
855 // co-ordinate state changes
857 // even if asked to allocate data, if the original packet
858 // holds static data, then the sender will not be doing
859 // any memcpy on receiving the response, thus we simply
860 // carry the pointer forward
861 if (pkt->flags.isSet(STATIC_DATA)) {
863 flags.set(STATIC_DATA);
871 * Generate the appropriate read MemCmd based on the Request flags.
874 makeReadCmd(const RequestPtr &req)
877 return MemCmd::LoadLockedReq;
878 else if (req->isPrefetchEx())
879 return MemCmd::SoftPFExReq;
880 else if (req->isPrefetch())
881 return MemCmd::SoftPFReq;
883 return MemCmd::ReadReq;
887 * Generate the appropriate write MemCmd based on the Request flags.
890 makeWriteCmd(const RequestPtr &req)
893 return MemCmd::StoreCondReq;
894 else if (req->isSwap() || req->isAtomic())
895 return MemCmd::SwapReq;
896 else if (req->isCacheInvalidate()) {
897 return req->isCacheClean() ? MemCmd::CleanInvalidReq :
898 MemCmd::InvalidateReq;
899 } else if (req->isCacheClean()) {
900 return MemCmd::CleanSharedReq;
902 return MemCmd::WriteReq;
906 * Constructor-like methods that return Packets based on Request objects.
907 * Fine-tune the MemCmd type if it's not a vanilla read or write.
910 createRead(const RequestPtr &req)
912 return new Packet(req, makeReadCmd(req));
916 createWrite(const RequestPtr &req)
918 return new Packet(req, makeWriteCmd(req));
922 * clean up packet variables
930 * Take a request packet and modify it in place to be suitable for
931 * returning as a response to that request.
936 assert(needsResponse());
938 cmd = cmd.responseCommand();
940 // responses are never express, even if the snoop that
941 // triggered them was
942 flags.clear(EXPRESS_SNOOP);
958 setFunctionalResponseStatus(bool success)
962 cmd = MemCmd::FunctionalWriteError;
964 cmd = MemCmd::FunctionalReadError;
970 setSize(unsigned size)
972 assert(!flags.isSet(VALID_SIZE));
975 flags.set(VALID_SIZE);
979 * Check if packet corresponds to a given block-aligned address and
982 * @param addr The address to compare against.
983 * @param is_secure Whether addr belongs to the secure address space.
984 * @param blk_size Block size in bytes.
985 * @return Whether packet matches description.
987 bool matchBlockAddr(const Addr addr, const bool is_secure,
988 const int blk_size) const;
991 * Check if this packet refers to the same block-aligned address and
992 * address space as another packet.
994 * @param pkt The packet to compare against.
995 * @param blk_size Block size in bytes.
996 * @return Whether packet matches description.
998 bool matchBlockAddr(const PacketPtr pkt, const int blk_size) const;
1001 * Check if packet corresponds to a given address and address space.
1003 * @param addr The address to compare against.
1004 * @param is_secure Whether addr belongs to the secure address space.
1005 * @return Whether packet matches description.
1007 bool matchAddr(const Addr addr, const bool is_secure) const;
1010 * Check if this packet refers to the same address and address space as
1013 * @param pkt The packet to compare against.
1014 * @return Whether packet matches description.
1016 bool matchAddr(const PacketPtr pkt) const;
1021 * @name Data accessor mehtods
1025 * Set the data pointer to the following value that should not be
1026 * freed. Static data allows us to do a single memcpy even if
1027 * multiple packets are required to get from source to destination
1028 * and back. In essence the pointer is set calling dataStatic on
1029 * the original packet, and whenever this packet is copied and
1030 * forwarded the same pointer is passed on. When a packet
1031 * eventually reaches the destination holding the data, it is
1032 * copied once into the location originally set. On the way back
1033 * to the source, no copies are necessary.
1035 template <typename T>
1039 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
1040 data = (PacketDataPtr)p;
1041 flags.set(STATIC_DATA);
1045 * Set the data pointer to the following value that should not be
1046 * freed. This version of the function allows the pointer passed
1047 * to us to be const. To avoid issues down the line we cast the
1048 * constness away, the alternative would be to keep both a const
1049 * and non-const data pointer and cleverly choose between
1050 * them. Note that this is only allowed for static data.
1052 template <typename T>
1054 dataStaticConst(const T *p)
1056 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
1057 data = const_cast<PacketDataPtr>(p);
1058 flags.set(STATIC_DATA);
1062 * Set the data pointer to a value that should have delete []
1063 * called on it. Dynamic data is local to this packet, and as the
1064 * packet travels from source to destination, forwarded packets
1065 * will allocate their own data. When a packet reaches the final
1066 * destination it will populate the dynamic data of that specific
1067 * packet, and on the way back towards the source, memcpy will be
1068 * invoked in every step where a new packet was created e.g. in
1069 * the caches. Ultimately when the response reaches the source a
1070 * final memcpy is needed to extract the data from the packet
1071 * before it is deallocated.
1073 template <typename T>
1077 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
1078 data = (PacketDataPtr)p;
1079 flags.set(DYNAMIC_DATA);
1083 * get a pointer to the data ptr.
1085 template <typename T>
1089 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
1090 assert(!isMaskedWrite());
1094 template <typename T>
1098 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
1099 return (const T*)data;
1103 * Get the data in the packet byte swapped from big endian to
1106 template <typename T>
1110 * Get the data in the packet byte swapped from little endian to
1113 template <typename T>
1117 * Get the data in the packet byte swapped from the specified
1120 template <typename T>
1121 T get(ByteOrder endian) const;
1123 /** Set the value in the data pointer to v as big endian. */
1124 template <typename T>
1127 /** Set the value in the data pointer to v as little endian. */
1128 template <typename T>
1132 * Set the value in the data pointer to v using the specified
1135 template <typename T>
1136 void set(T v, ByteOrder endian);
1139 * Get the data in the packet byte swapped from the specified
1140 * endianness and zero-extended to 64 bits.
1142 uint64_t getUintX(ByteOrder endian) const;
1145 * Set the value in the word w after truncating it to the length
1146 * of the packet and then byteswapping it to the desired
1149 void setUintX(uint64_t w, ByteOrder endian);
1152 * Copy data into the packet from the provided pointer.
1155 setData(const uint8_t *p)
1157 // we should never be copying data onto itself, which means we
1158 // must idenfity packets with static data, as they carry the
1159 // same pointer from source to destination and back
1160 assert(p != getPtr<uint8_t>() || flags.isSet(STATIC_DATA));
1162 if (p != getPtr<uint8_t>()) {
1163 // for packet with allocated dynamic data, we copy data from
1164 // one to the other, e.g. a forwarded response to a response
1165 std::memcpy(getPtr<uint8_t>(), p, getSize());
1170 * Copy data into the packet from the provided block pointer,
1171 * which is aligned to the given block size.
1174 setDataFromBlock(const uint8_t *blk_data, int blkSize)
1176 setData(blk_data + getOffset(blkSize));
1180 * Copy data from the packet to the memory at the provided pointer.
1181 * @param p Pointer to which data will be copied.
1184 writeData(uint8_t *p) const
1186 if (!isMaskedWrite()) {
1187 std::memcpy(p, getConstPtr<uint8_t>(), getSize());
1189 assert(req->getByteEnable().size() == getSize());
1190 // Write only the enabled bytes
1191 const uint8_t *base = getConstPtr<uint8_t>();
1192 for (int i = 0; i < getSize(); i++) {
1193 if (req->getByteEnable()[i]) {
1196 // Disabled bytes stay untouched
1202 * Copy data from the packet to the provided block pointer, which
1203 * is aligned to the given block size.
1204 * @param blk_data Pointer to block to which data will be copied.
1205 * @param blkSize Block size in bytes.
1208 writeDataToBlock(uint8_t *blk_data, int blkSize) const
1210 writeData(blk_data + getOffset(blkSize));
1214 * delete the data pointed to in the data pointer. Ok to call to
1215 * matter how data was allocted.
1220 if (flags.isSet(DYNAMIC_DATA))
1223 flags.clear(STATIC_DATA|DYNAMIC_DATA);
1227 /** Allocate memory for the packet. */
1231 // if either this command or the response command has a data
1232 // payload, actually allocate space
1233 if (hasData() || hasRespData()) {
1234 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
1235 flags.set(DYNAMIC_DATA);
1236 data = new uint8_t[getSize()];
1242 /** Get the data in the packet without byte swapping. */
1243 template <typename T>
1246 /** Set the value in the data pointer to v without byte swapping. */
1247 template <typename T>
1252 * Check a functional request against a memory value stored in
1253 * another packet (i.e. an in-transit request or
1254 * response). Returns true if the current packet is a read, and
1255 * the other packet provides the data, which is then copied to the
1256 * current packet. If the current packet is a write, and the other
1257 * packet intersects this one, then we update the data
1261 trySatisfyFunctional(PacketPtr other)
1263 if (other->isMaskedWrite()) {
1264 // Do not forward data if overlapping with a masked write
1265 if (_isSecure == other->isSecure() &&
1266 getAddr() <= (other->getAddr() + other->getSize() - 1) &&
1267 other->getAddr() <= (getAddr() + getSize() - 1)) {
1268 warn("Trying to check against a masked write, skipping."
1269 " (addr: 0x%x, other addr: 0x%x)", getAddr(),
1274 // all packets that are carrying a payload should have a valid
1276 return trySatisfyFunctional(other, other->getAddr(), other->isSecure(),
1279 other->getPtr<uint8_t>() : NULL);
1283 * Does the request need to check for cached copies of the same block
1284 * in the memory hierarchy above.
1287 mustCheckAbove() const
1289 return cmd == MemCmd::HardPFReq || isEviction();
1293 * Is this packet a clean eviction, including both actual clean
1294 * evict packets, but also clean writebacks.
1297 isCleanEviction() const
1299 return cmd == MemCmd::CleanEvict || cmd == MemCmd::WritebackClean;
1303 isMaskedWrite() const
1305 return (cmd == MemCmd::WriteReq && req->isMasked());
1309 * Check a functional request against a memory value represented
1310 * by a base/size pair and an associated data array. If the
1311 * current packet is a read, it may be satisfied by the memory
1312 * value. If the current packet is a write, it may update the
1316 trySatisfyFunctional(Printable *obj, Addr base, bool is_secure, int size,
1320 * Push label for PrintReq (safe to call unconditionally).
1323 pushLabel(const std::string &lbl)
1326 safe_cast<PrintReqState*>(senderState)->pushLabel(lbl);
1330 * Pop label for PrintReq (safe to call unconditionally).
1336 safe_cast<PrintReqState*>(senderState)->popLabel();
1339 void print(std::ostream &o, int verbosity = 0,
1340 const std::string &prefix = "") const;
1343 * A no-args wrapper of print(std::ostream...)
1344 * meant to be invoked from DPRINTFs
1345 * avoiding string overheads in fast mode
1346 * @return string with the request's type and start<->end addresses
1348 std::string print() const;
1351 #endif //__MEM_PACKET_HH