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39 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
41 * Authors: Ron Dreslinski
50 * Declaration of the Packet class.
53 #ifndef __MEM_PACKET_HH__
54 #define __MEM_PACKET_HH__
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"
70 typedef Packet *PacketPtr;
71 typedef uint8_t* PacketDataPtr;
72 typedef std::list<PacketPtr> PacketList;
73 typedef uint64_t PacketId;
81 * List of all commands associated with a packet.
88 ReadRespWithInvalidate,
93 WriteClean, // writes dirty data below without evicting
101 SCUpgradeReq, // Special "weak" upgrade for StoreCond
103 SCUpgradeFailReq, // Failed SCUpgradeReq in MSHR (never sent)
104 UpgradeFailResp, // Valid for SCUpgradeReq only
111 StoreCondFailReq, // Failed StoreCondReq in MSHR (never sent)
124 // @TODO these should be classified as responses rather than
125 // requests; coding them as requests initially for backwards
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
141 * List of command attributes.
145 IsRead, //!< Data flows from responder to requester
146 IsWrite, //!< Data flows from requester to responder
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
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
167 * Structure that defines attributes and other data associated
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;
181 /// Array to map Command enum to associated info.
182 static const CommandInfo commandInfo[];
189 testCmdAttrib(MemCmd::Attribute attrib) const
191 return commandInfo[cmd].attributes[attrib] != 0;
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); }
209 * A writeback is an eviction that carries data.
211 bool isWriteback() const { return testCmdAttrib(IsEviction) &&
212 testCmdAttrib(HasData); }
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
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); }
230 responseCommand() const
232 return commandInfo[cmd].response;
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; }
239 MemCmd(Command _cmd) : cmd(_cmd) { }
240 MemCmd(int _cmd) : cmd((Command)_cmd) { }
241 MemCmd() : cmd(InvalidCmd) { }
243 bool operator==(MemCmd c2) const { return (cmd == c2.cmd); }
244 bool operator!=(MemCmd c2) const { return (cmd != c2.cmd); }
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.)
254 class Packet : public Printable
257 typedef uint32_t FlagsType;
258 typedef ::Flags<FlagsType> Flags;
263 // Flags to transfer across when copying a packet
264 COPY_FLAGS = 0x0000003F,
266 // Does this packet have sharers (which means it should not be
267 // considered writable) or not. See setHasSharers below.
268 HAS_SHARERS = 0x00000001,
270 // Special control flags
271 /// Special timing-mode atomic snoop for multi-level coherence.
272 EXPRESS_SNOOP = 0x00000002,
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,
279 // Snoop co-ordination flag to indicate that a cache is
280 // responding to a snoop. See setCacheResponding below.
281 CACHE_RESPONDING = 0x00000008,
283 // The writeback/writeclean should be propagated further
284 // downstream by the receiver
285 WRITE_THROUGH = 0x00000010,
287 // Response co-ordination flag for cache maintenance
289 SATISFIED = 0x00000020,
291 /// Are the 'addr' and 'size' fields valid?
292 VALID_ADDR = 0x00000100,
293 VALID_SIZE = 0x00000200,
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,
303 /// suppress the error if this packet encounters a functional
305 SUPPRESS_FUNC_ERROR = 0x00008000,
307 // Signal block present to squash prefetch and cache evict packets
308 // through express snoop flag
309 BLOCK_CACHED = 0x00010000
315 typedef MemCmd::Command Command;
317 /// The command field of the packet.
322 /// A pointer to the original request.
323 const RequestPtr req;
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
335 /// The address of the request. This address could be virtual or
336 /// physical, depending on the system configuration.
339 /// True if the request targets the secure memory space.
342 /// The size of the request or transfer.
346 * Track the bytes found that satisfy a functional read.
348 std::vector<bool> bytesValid;
353 * The extra delay from seeing the packet until the header is
354 * transmitted. This delay is used to communicate the crossbar
355 * forwarding latency to the neighbouring object (e.g. a cache)
356 * that actually makes the packet wait. As the delay is relative,
357 * a 32-bit unsigned should be sufficient.
359 uint32_t headerDelay;
362 * Keep track of the extra delay incurred by snooping upwards
363 * before sending a request down the memory system. This is used
364 * by the coherent crossbar to account for the additional request
370 * The extra pipelining delay from seeing the packet until the end of
371 * payload is transmitted by the component that provided it (if
372 * any). This includes the header delay. Similar to the header
373 * delay, this is used to make up for the fact that the
374 * crossbar does not make the packet wait. As the delay is
375 * relative, a 32-bit unsigned should be sufficient.
377 uint32_t payloadDelay;
380 * A virtual base opaque structure used to hold state associated
381 * with the packet (e.g., an MSHR), specific to a MemObject that
382 * sees the packet. A pointer to this state is returned in the
383 * packet's response so that the MemObject in question can quickly
384 * look up the state needed to process it. A specific subclass
385 * would be derived from this to carry state specific to a
386 * particular sending device.
388 * As multiple MemObjects may add their SenderState throughout the
389 * memory system, the SenderStates create a stack, where a
390 * MemObject can add a new Senderstate, as long as the
391 * predecessing SenderState is restored when the response comes
392 * back. For this reason, the predecessor should always be
393 * populated with the current SenderState of a packet before
394 * modifying the senderState field in the request packet.
398 SenderState* predecessor;
399 SenderState() : predecessor(NULL) {}
400 virtual ~SenderState() {}
404 * Object used to maintain state of a PrintReq. The senderState
405 * field of a PrintReq should always be of this type.
407 class PrintReqState : public SenderState
411 * An entry in the label stack.
413 struct LabelStackEntry
415 const std::string label;
418 LabelStackEntry(const std::string &_label, std::string *_prefix);
421 typedef std::list<LabelStackEntry> LabelStack;
422 LabelStack labelStack;
424 std::string *curPrefixPtr;
430 PrintReqState(std::ostream &os, int verbosity = 0);
434 * Returns the current line prefix.
436 const std::string &curPrefix() { return *curPrefixPtr; }
439 * Push a label onto the label stack, and prepend the given
440 * prefix string onto the current prefix. Labels will only be
441 * printed if an object within the label's scope is printed.
443 void pushLabel(const std::string &lbl,
444 const std::string &prefix = " ");
447 * Pop a label off the label stack.
452 * Print all of the pending unprinted labels on the
453 * stack. Called by printObj(), so normally not called by
454 * users unless bypassing printObj().
459 * Print a Printable object to os, because it matched the
460 * address on a PrintReq.
462 void printObj(Printable *obj);
466 * This packet's sender state. Devices should use dynamic_cast<>
467 * to cast to the state appropriate to the sender. The intent of
468 * this variable is to allow a device to attach extra information
469 * to a request. A response packet must return the sender state
470 * that was attached to the original request (even if a new packet
473 SenderState *senderState;
476 * Push a new sender state to the packet and make the current
477 * sender state the predecessor of the new one. This should be
478 * prefered over direct manipulation of the senderState member
481 * @param sender_state SenderState to push at the top of the stack
483 void pushSenderState(SenderState *sender_state);
486 * Pop the top of the state stack and return a pointer to it. This
487 * assumes the current sender state is not NULL. This should be
488 * preferred over direct manipulation of the senderState member
491 * @return The current top of the stack
493 SenderState *popSenderState();
496 * Go through the sender state stack and return the first instance
497 * that is of type T (as determined by a dynamic_cast). If there
498 * is no sender state of type T, NULL is returned.
500 * @return The topmost state of type T
502 template <typename T>
503 T * findNextSenderState() const
506 SenderState* sender_state = senderState;
507 while (t == NULL && sender_state != NULL) {
508 t = dynamic_cast<T*>(sender_state);
509 sender_state = sender_state->predecessor;
514 /// Return the string name of the cmd field (for debugging and
516 const std::string &cmdString() const { return cmd.toString(); }
518 /// Return the index of this command.
519 inline int cmdToIndex() const { return cmd.toInt(); }
521 bool isRead() const { return cmd.isRead(); }
522 bool isWrite() const { return cmd.isWrite(); }
523 bool isUpgrade() const { return cmd.isUpgrade(); }
524 bool isRequest() const { return cmd.isRequest(); }
525 bool isResponse() const { return cmd.isResponse(); }
526 bool needsWritable() const
528 // we should never check if a response needsWritable, the
529 // request has this flag, and for a response we should rather
530 // look at the hasSharers flag (if not set, the response is to
531 // be considered writable)
533 return cmd.needsWritable();
535 bool needsResponse() const { return cmd.needsResponse(); }
536 bool isInvalidate() const { return cmd.isInvalidate(); }
537 bool isEviction() const { return cmd.isEviction(); }
538 bool isClean() const { return cmd.isClean(); }
539 bool fromCache() const { return cmd.fromCache(); }
540 bool isWriteback() const { return cmd.isWriteback(); }
541 bool hasData() const { return cmd.hasData(); }
542 bool hasRespData() const
544 MemCmd resp_cmd = cmd.responseCommand();
545 return resp_cmd.hasData();
547 bool isLLSC() const { return cmd.isLLSC(); }
548 bool isError() const { return cmd.isError(); }
549 bool isPrint() const { return cmd.isPrint(); }
550 bool isFlush() const { return cmd.isFlush(); }
555 * Set the cacheResponding flag. This is used by the caches to
556 * signal another cache that they are responding to a request. A
557 * cache will only respond to snoops if it has the line in either
558 * Modified or Owned state. Note that on snoop hits we always pass
559 * the line as Modified and never Owned. In the case of an Owned
560 * line we proceed to invalidate all other copies.
562 * On a cache fill (see Cache::handleFill), we check hasSharers
563 * first, ignoring the cacheResponding flag if hasSharers is set.
564 * A line is consequently allocated as:
566 * hasSharers cacheResponding state
569 * false false Exclusive
570 * false true Modified
572 void setCacheResponding()
575 assert(!flags.isSet(CACHE_RESPONDING));
576 flags.set(CACHE_RESPONDING);
578 bool cacheResponding() const { return flags.isSet(CACHE_RESPONDING); }
580 * On fills, the hasSharers flag is used by the caches in
581 * combination with the cacheResponding flag, as clarified
582 * above. If the hasSharers flag is not set, the packet is passing
583 * writable. Thus, a response from a memory passes the line as
584 * writable by default.
586 * The hasSharers flag is also used by upstream caches to inform a
587 * downstream cache that they have the block (by calling
588 * setHasSharers on snoop request packets that hit in upstream
589 * cachs tags or MSHRs). If the snoop packet has sharers, a
590 * downstream cache is prevented from passing a dirty line upwards
591 * if it was not explicitly asked for a writable copy. See
592 * Cache::satisfyCpuSideRequest.
594 * The hasSharers flag is also used on writebacks, in
595 * combination with the WritbackClean or WritebackDirty commands,
596 * to allocate the block downstream either as:
598 * command hasSharers state
599 * WritebackDirty false Modified
600 * WritebackDirty true Owned
601 * WritebackClean false Exclusive
602 * WritebackClean true Shared
604 void setHasSharers() { flags.set(HAS_SHARERS); }
605 bool hasSharers() const { return flags.isSet(HAS_SHARERS); }
609 * The express snoop flag is used for two purposes. Firstly, it is
610 * used to bypass flow control for normal (non-snoop) requests
611 * going downstream in the memory system. In cases where a cache
612 * is responding to a snoop from another cache (it had a dirty
613 * line), but the line is not writable (and there are possibly
614 * other copies), the express snoop flag is set by the downstream
615 * cache to invalidate all other copies in zero time. Secondly,
616 * the express snoop flag is also set to be able to distinguish
617 * snoop packets that came from a downstream cache, rather than
618 * snoop packets from neighbouring caches.
620 void setExpressSnoop() { flags.set(EXPRESS_SNOOP); }
621 bool isExpressSnoop() const { return flags.isSet(EXPRESS_SNOOP); }
624 * On responding to a snoop request (which only happens for
625 * Modified or Owned lines), make sure that we can transform an
626 * Owned response to a Modified one. If this flag is not set, the
627 * responding cache had the line in the Owned state, and there are
628 * possibly other Shared copies in the memory system. A downstream
629 * cache helps in orchestrating the invalidation of these copies
630 * by sending out the appropriate express snoops.
632 void setResponderHadWritable()
634 assert(cacheResponding());
635 assert(!responderHadWritable());
636 flags.set(RESPONDER_HAD_WRITABLE);
638 bool responderHadWritable() const
639 { return flags.isSet(RESPONDER_HAD_WRITABLE); }
642 * A writeback/writeclean cmd gets propagated further downstream
643 * by the receiver when the flag is set.
645 void setWriteThrough()
647 assert(cmd.isWrite() &&
648 (cmd.isEviction() || cmd == MemCmd::WriteClean));
649 flags.set(WRITE_THROUGH);
651 void clearWriteThrough() { flags.clear(WRITE_THROUGH); }
652 bool writeThrough() const { return flags.isSet(WRITE_THROUGH); }
655 * Set when a request hits in a cache and the cache is not going
656 * to respond. This is used by the crossbar to coordinate
657 * responses for cache maintenance operations.
661 assert(cmd.isClean());
662 assert(!flags.isSet(SATISFIED));
663 flags.set(SATISFIED);
665 bool satisfied() const { return flags.isSet(SATISFIED); }
667 void setSuppressFuncError() { flags.set(SUPPRESS_FUNC_ERROR); }
668 bool suppressFuncError() const { return flags.isSet(SUPPRESS_FUNC_ERROR); }
669 void setBlockCached() { flags.set(BLOCK_CACHED); }
670 bool isBlockCached() const { return flags.isSet(BLOCK_CACHED); }
671 void clearBlockCached() { flags.clear(BLOCK_CACHED); }
673 // Network error conditions... encapsulate them as methods since
674 // their encoding keeps changing (from result field to command
679 assert(isResponse());
680 cmd = MemCmd::BadAddressError;
683 void copyError(Packet *pkt) { assert(pkt->isError()); cmd = pkt->cmd; }
685 Addr getAddr() const { assert(flags.isSet(VALID_ADDR)); return addr; }
687 * Update the address of this packet mid-transaction. This is used
688 * by the address mapper to change an already set address to a new
689 * one based on the system configuration. It is intended to remap
690 * an existing address, so it asserts that the current address is
693 void setAddr(Addr _addr) { assert(flags.isSet(VALID_ADDR)); addr = _addr; }
695 unsigned getSize() const { assert(flags.isSet(VALID_SIZE)); return size; }
697 Addr getOffset(unsigned int blk_size) const
699 return getAddr() & Addr(blk_size - 1);
702 Addr getBlockAddr(unsigned int blk_size) const
704 return getAddr() & ~(Addr(blk_size - 1));
707 bool isSecure() const
709 assert(flags.isSet(VALID_ADDR));
714 * Accessor function to atomic op.
716 AtomicOpFunctor *getAtomicOp() const { return req->getAtomicOpFunctor(); }
717 bool isAtomicOp() const { return req->isAtomic(); }
720 * It has been determined that the SC packet should successfully update
721 * memory. Therefore, convert this SC packet to a normal write.
728 cmd = MemCmd::WriteReq;
732 * When ruby is in use, Ruby will monitor the cache line and the
733 * phys memory should treat LL ops as normal reads.
740 cmd = MemCmd::ReadReq;
744 * Constructor. Note that a Request object must be constructed
745 * first, but the Requests's physical address and size fields need
746 * not be valid. The command must be supplied.
748 Packet(const RequestPtr _req, MemCmd _cmd)
749 : cmd(_cmd), id((PacketId)_req), req(_req), data(nullptr), addr(0),
750 _isSecure(false), size(0), headerDelay(0), snoopDelay(0),
751 payloadDelay(0), senderState(NULL)
753 if (req->hasPaddr()) {
754 addr = req->getPaddr();
755 flags.set(VALID_ADDR);
756 _isSecure = req->isSecure();
758 if (req->hasSize()) {
759 size = req->getSize();
760 flags.set(VALID_SIZE);
765 * Alternate constructor if you are trying to create a packet with
766 * a request that is for a whole block, not the address from the
767 * req. this allows for overriding the size/addr of the req.
769 Packet(const RequestPtr _req, MemCmd _cmd, int _blkSize, PacketId _id = 0)
770 : cmd(_cmd), id(_id ? _id : (PacketId)_req), req(_req), data(nullptr),
771 addr(0), _isSecure(false), headerDelay(0), snoopDelay(0),
772 payloadDelay(0), senderState(NULL)
774 if (req->hasPaddr()) {
775 addr = req->getPaddr() & ~(_blkSize - 1);
776 flags.set(VALID_ADDR);
777 _isSecure = req->isSecure();
780 flags.set(VALID_SIZE);
784 * Alternate constructor for copying a packet. Copy all fields
785 * *except* if the original packet's data was dynamic, don't copy
786 * that, as we can't guarantee that the new packet's lifetime is
787 * less than that of the original packet. In this case the new
788 * packet should allocate its own data.
790 Packet(const PacketPtr pkt, bool clear_flags, bool alloc_data)
791 : cmd(pkt->cmd), id(pkt->id), req(pkt->req),
793 addr(pkt->addr), _isSecure(pkt->_isSecure), size(pkt->size),
794 bytesValid(pkt->bytesValid),
795 headerDelay(pkt->headerDelay),
797 payloadDelay(pkt->payloadDelay),
798 senderState(pkt->senderState)
801 flags.set(pkt->flags & COPY_FLAGS);
803 flags.set(pkt->flags & (VALID_ADDR|VALID_SIZE));
805 // should we allocate space for data, or not, the express
806 // snoops do not need to carry any data as they only serve to
807 // co-ordinate state changes
809 // even if asked to allocate data, if the original packet
810 // holds static data, then the sender will not be doing
811 // any memcpy on receiving the response, thus we simply
812 // carry the pointer forward
813 if (pkt->flags.isSet(STATIC_DATA)) {
815 flags.set(STATIC_DATA);
823 * Generate the appropriate read MemCmd based on the Request flags.
826 makeReadCmd(const RequestPtr req)
829 return MemCmd::LoadLockedReq;
830 else if (req->isPrefetch())
831 return MemCmd::SoftPFReq;
833 return MemCmd::ReadReq;
837 * Generate the appropriate write MemCmd based on the Request flags.
840 makeWriteCmd(const RequestPtr req)
843 return MemCmd::StoreCondReq;
844 else if (req->isSwap())
845 return MemCmd::SwapReq;
846 else if (req->isCacheInvalidate()) {
847 return req->isCacheClean() ? MemCmd::CleanInvalidReq :
848 MemCmd::InvalidateReq;
849 } else if (req->isCacheClean()) {
850 return MemCmd::CleanSharedReq;
852 return MemCmd::WriteReq;
856 * Constructor-like methods that return Packets based on Request objects.
857 * Fine-tune the MemCmd type if it's not a vanilla read or write.
860 createRead(const RequestPtr req)
862 return new Packet(req, makeReadCmd(req));
866 createWrite(const RequestPtr req)
868 return new Packet(req, makeWriteCmd(req));
872 * clean up packet variables
876 // Delete the request object if this is a request packet which
877 // does not need a response, because the requester will not get
878 // a chance. If the request packet needs a response then the
879 // request will be deleted on receipt of the response
880 // packet. We also make sure to never delete the request for
881 // express snoops, even for cases when responses are not
882 // needed (CleanEvict and Writeback), since the snoop packet
883 // re-uses the same request.
884 if (req && isRequest() && !needsResponse() &&
892 * Take a request packet and modify it in place to be suitable for
893 * returning as a response to that request.
898 assert(needsResponse());
900 cmd = cmd.responseCommand();
902 // responses are never express, even if the snoop that
903 // triggered them was
904 flags.clear(EXPRESS_SNOOP);
920 setFunctionalResponseStatus(bool success)
924 cmd = MemCmd::FunctionalWriteError;
926 cmd = MemCmd::FunctionalReadError;
932 setSize(unsigned size)
934 assert(!flags.isSet(VALID_SIZE));
937 flags.set(VALID_SIZE);
944 * @name Data accessor mehtods
948 * Set the data pointer to the following value that should not be
949 * freed. Static data allows us to do a single memcpy even if
950 * multiple packets are required to get from source to destination
951 * and back. In essence the pointer is set calling dataStatic on
952 * the original packet, and whenever this packet is copied and
953 * forwarded the same pointer is passed on. When a packet
954 * eventually reaches the destination holding the data, it is
955 * copied once into the location originally set. On the way back
956 * to the source, no copies are necessary.
958 template <typename T>
962 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
963 data = (PacketDataPtr)p;
964 flags.set(STATIC_DATA);
968 * Set the data pointer to the following value that should not be
969 * freed. This version of the function allows the pointer passed
970 * to us to be const. To avoid issues down the line we cast the
971 * constness away, the alternative would be to keep both a const
972 * and non-const data pointer and cleverly choose between
973 * them. Note that this is only allowed for static data.
975 template <typename T>
977 dataStaticConst(const T *p)
979 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
980 data = const_cast<PacketDataPtr>(p);
981 flags.set(STATIC_DATA);
985 * Set the data pointer to a value that should have delete []
986 * called on it. Dynamic data is local to this packet, and as the
987 * packet travels from source to destination, forwarded packets
988 * will allocate their own data. When a packet reaches the final
989 * destination it will populate the dynamic data of that specific
990 * packet, and on the way back towards the source, memcpy will be
991 * invoked in every step where a new packet was created e.g. in
992 * the caches. Ultimately when the response reaches the source a
993 * final memcpy is needed to extract the data from the packet
994 * before it is deallocated.
996 template <typename T>
1000 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
1001 data = (PacketDataPtr)p;
1002 flags.set(DYNAMIC_DATA);
1006 * get a pointer to the data ptr.
1008 template <typename T>
1012 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
1016 template <typename T>
1020 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
1021 return (const T*)data;
1025 * Get the data in the packet byte swapped from big endian to
1028 template <typename T>
1032 * Get the data in the packet byte swapped from little endian to
1035 template <typename T>
1039 * Get the data in the packet byte swapped from the specified
1042 template <typename T>
1043 T get(ByteOrder endian) const;
1046 * Get the data in the packet byte swapped from guest to host
1049 template <typename T>
1052 /** Set the value in the data pointer to v as big endian. */
1053 template <typename T>
1056 /** Set the value in the data pointer to v as little endian. */
1057 template <typename T>
1061 * Set the value in the data pointer to v using the specified
1064 template <typename T>
1065 void set(T v, ByteOrder endian);
1067 /** Set the value in the data pointer to v as guest endian. */
1068 template <typename T>
1072 * Copy data into the packet from the provided pointer.
1075 setData(const uint8_t *p)
1077 // we should never be copying data onto itself, which means we
1078 // must idenfity packets with static data, as they carry the
1079 // same pointer from source to destination and back
1080 assert(p != getPtr<uint8_t>() || flags.isSet(STATIC_DATA));
1082 if (p != getPtr<uint8_t>())
1083 // for packet with allocated dynamic data, we copy data from
1084 // one to the other, e.g. a forwarded response to a response
1085 std::memcpy(getPtr<uint8_t>(), p, getSize());
1089 * Copy data into the packet from the provided block pointer,
1090 * which is aligned to the given block size.
1093 setDataFromBlock(const uint8_t *blk_data, int blkSize)
1095 setData(blk_data + getOffset(blkSize));
1099 * Copy data from the packet to the memory at the provided pointer.
1100 * @param p Pointer to which data will be copied.
1103 writeData(uint8_t *p) const
1105 std::memcpy(p, getConstPtr<uint8_t>(), getSize());
1109 * Copy data from the packet to the provided block pointer, which
1110 * is aligned to the given block size.
1111 * @param blk_data Pointer to block to which data will be copied.
1112 * @param blkSize Block size in bytes.
1115 writeDataToBlock(uint8_t *blk_data, int blkSize) const
1117 writeData(blk_data + getOffset(blkSize));
1121 * delete the data pointed to in the data pointer. Ok to call to
1122 * matter how data was allocted.
1127 if (flags.isSet(DYNAMIC_DATA))
1130 flags.clear(STATIC_DATA|DYNAMIC_DATA);
1134 /** Allocate memory for the packet. */
1138 // if either this command or the response command has a data
1139 // payload, actually allocate space
1140 if (hasData() || hasRespData()) {
1141 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
1142 flags.set(DYNAMIC_DATA);
1143 data = new uint8_t[getSize()];
1149 private: // Private data accessor methods
1150 /** Get the data in the packet without byte swapping. */
1151 template <typename T>
1154 /** Set the value in the data pointer to v without byte swapping. */
1155 template <typename T>
1160 * Check a functional request against a memory value stored in
1161 * another packet (i.e. an in-transit request or
1162 * response). Returns true if the current packet is a read, and
1163 * the other packet provides the data, which is then copied to the
1164 * current packet. If the current packet is a write, and the other
1165 * packet intersects this one, then we update the data
1169 checkFunctional(PacketPtr other)
1171 // all packets that are carrying a payload should have a valid
1173 return checkFunctional(other, other->getAddr(), other->isSecure(),
1176 other->getPtr<uint8_t>() : NULL);
1180 * Does the request need to check for cached copies of the same block
1181 * in the memory hierarchy above.
1184 mustCheckAbove() const
1186 return cmd == MemCmd::HardPFReq || isEviction();
1190 * Is this packet a clean eviction, including both actual clean
1191 * evict packets, but also clean writebacks.
1194 isCleanEviction() const
1196 return cmd == MemCmd::CleanEvict || cmd == MemCmd::WritebackClean;
1200 * Check a functional request against a memory value represented
1201 * by a base/size pair and an associated data array. If the
1202 * current packet is a read, it may be satisfied by the memory
1203 * value. If the current packet is a write, it may update the
1207 checkFunctional(Printable *obj, Addr base, bool is_secure, int size,
1211 * Push label for PrintReq (safe to call unconditionally).
1214 pushLabel(const std::string &lbl)
1217 safe_cast<PrintReqState*>(senderState)->pushLabel(lbl);
1221 * Pop label for PrintReq (safe to call unconditionally).
1227 safe_cast<PrintReqState*>(senderState)->popLabel();
1230 void print(std::ostream &o, int verbosity = 0,
1231 const std::string &prefix = "") const;
1234 * A no-args wrapper of print(std::ostream...)
1235 * meant to be invoked from DPRINTFs
1236 * avoiding string overheads in fast mode
1237 * @return string with the request's type and start<->end addresses
1239 std::string print() const;
1242 #endif //__MEM_PACKET_HH