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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;
80 * List of all commands associated with a packet.
87 ReadRespWithInvalidate,
92 WriteClean, // writes dirty data below without evicting
100 SCUpgradeReq, // Special "weak" upgrade for StoreCond
102 SCUpgradeFailReq, // Failed SCUpgradeReq in MSHR (never sent)
103 UpgradeFailResp, // Valid for SCUpgradeReq only
110 StoreCondFailReq, // Failed StoreCondReq in MSHR (never sent)
123 // @TODO these should be classified as responses rather than
124 // requests; coding them as requests initially for backwards
126 InvalidDestError, // packet dest field invalid
127 BadAddressError, // memory address invalid
128 FunctionalReadError, // unable to fulfill functional read
129 FunctionalWriteError, // unable to fulfill functional write
130 // Fake simulator-only commands
131 PrintReq, // Print state matching address
132 FlushReq, //request for a cache flush
133 InvalidateReq, // request for address to be invalidated
140 * List of command attributes.
144 IsRead, //!< Data flows from responder to requester
145 IsWrite, //!< Data flows from requester to responder
148 IsClean, //!< Cleans any existing dirty blocks
149 NeedsWritable, //!< Requires writable copy to complete in-cache
150 IsRequest, //!< Issued by requester
151 IsResponse, //!< Issue by responder
152 NeedsResponse, //!< Requester needs response from target
156 IsLlsc, //!< Alpha/MIPS LL or SC access
157 HasData, //!< There is an associated payload
158 IsError, //!< Error response
159 IsPrint, //!< Print state matching address (for debugging)
160 IsFlush, //!< Flush the address from caches
161 FromCache, //!< Request originated from a caching agent
162 NUM_COMMAND_ATTRIBUTES
166 * Structure that defines attributes and other data associated
171 /// Set of attribute flags.
172 const std::bitset<NUM_COMMAND_ATTRIBUTES> attributes;
173 /// Corresponding response for requests; InvalidCmd if no
174 /// response is applicable.
175 const Command response;
176 /// String representation (for printing)
177 const std::string str;
180 /// Array to map Command enum to associated info.
181 static const CommandInfo commandInfo[];
188 testCmdAttrib(MemCmd::Attribute attrib) const
190 return commandInfo[cmd].attributes[attrib] != 0;
195 bool isRead() const { return testCmdAttrib(IsRead); }
196 bool isWrite() const { return testCmdAttrib(IsWrite); }
197 bool isUpgrade() const { return testCmdAttrib(IsUpgrade); }
198 bool isRequest() const { return testCmdAttrib(IsRequest); }
199 bool isResponse() const { return testCmdAttrib(IsResponse); }
200 bool needsWritable() const { return testCmdAttrib(NeedsWritable); }
201 bool needsResponse() const { return testCmdAttrib(NeedsResponse); }
202 bool isInvalidate() const { return testCmdAttrib(IsInvalidate); }
203 bool isEviction() const { return testCmdAttrib(IsEviction); }
204 bool isClean() const { return testCmdAttrib(IsClean); }
205 bool fromCache() const { return testCmdAttrib(FromCache); }
208 * A writeback is an eviction that carries data.
210 bool isWriteback() const { return testCmdAttrib(IsEviction) &&
211 testCmdAttrib(HasData); }
214 * Check if this particular packet type carries payload data. Note
215 * that this does not reflect if the data pointer of the packet is
218 bool hasData() const { return testCmdAttrib(HasData); }
219 bool isLLSC() const { return testCmdAttrib(IsLlsc); }
220 bool isSWPrefetch() const { return testCmdAttrib(IsSWPrefetch); }
221 bool isHWPrefetch() const { return testCmdAttrib(IsHWPrefetch); }
222 bool isPrefetch() const { return testCmdAttrib(IsSWPrefetch) ||
223 testCmdAttrib(IsHWPrefetch); }
224 bool isError() const { return testCmdAttrib(IsError); }
225 bool isPrint() const { return testCmdAttrib(IsPrint); }
226 bool isFlush() const { return testCmdAttrib(IsFlush); }
229 responseCommand() const
231 return commandInfo[cmd].response;
234 /// Return the string to a cmd given by idx.
235 const std::string &toString() const { return commandInfo[cmd].str; }
236 int toInt() const { return (int)cmd; }
238 MemCmd(Command _cmd) : cmd(_cmd) { }
239 MemCmd(int _cmd) : cmd((Command)_cmd) { }
240 MemCmd() : cmd(InvalidCmd) { }
242 bool operator==(MemCmd c2) const { return (cmd == c2.cmd); }
243 bool operator!=(MemCmd c2) const { return (cmd != c2.cmd); }
247 * A Packet is used to encapsulate a transfer between two objects in
248 * the memory system (e.g., the L1 and L2 cache). (In contrast, a
249 * single Request travels all the way from the requester to the
250 * ultimate destination and back, possibly being conveyed by several
251 * different Packets along the way.)
253 class Packet : public Printable
256 typedef uint32_t FlagsType;
257 typedef ::Flags<FlagsType> Flags;
262 // Flags to transfer across when copying a packet
263 COPY_FLAGS = 0x0000003F,
265 // Does this packet have sharers (which means it should not be
266 // considered writable) or not. See setHasSharers below.
267 HAS_SHARERS = 0x00000001,
269 // Special control flags
270 /// Special timing-mode atomic snoop for multi-level coherence.
271 EXPRESS_SNOOP = 0x00000002,
273 /// Allow a responding cache to inform the cache hierarchy
274 /// that it had a writable copy before responding. See
275 /// setResponderHadWritable below.
276 RESPONDER_HAD_WRITABLE = 0x00000004,
278 // Snoop co-ordination flag to indicate that a cache is
279 // responding to a snoop. See setCacheResponding below.
280 CACHE_RESPONDING = 0x00000008,
282 // The writeback/writeclean should be propagated further
283 // downstream by the receiver
284 WRITE_THROUGH = 0x00000010,
286 // Response co-ordination flag for cache maintenance
288 SATISFIED = 0x00000020,
290 /// Are the 'addr' and 'size' fields valid?
291 VALID_ADDR = 0x00000100,
292 VALID_SIZE = 0x00000200,
294 /// Is the data pointer set to a value that shouldn't be freed
295 /// when the packet is destroyed?
296 STATIC_DATA = 0x00001000,
297 /// The data pointer points to a value that should be freed when
298 /// the packet is destroyed. The pointer is assumed to be pointing
299 /// to an array, and delete [] is consequently called
300 DYNAMIC_DATA = 0x00002000,
302 /// suppress the error if this packet encounters a functional
304 SUPPRESS_FUNC_ERROR = 0x00008000,
306 // Signal block present to squash prefetch and cache evict packets
307 // through express snoop flag
308 BLOCK_CACHED = 0x00010000
314 typedef MemCmd::Command Command;
316 /// The command field of the packet.
319 /// A pointer to the original request.
320 const RequestPtr req;
324 * A pointer to the data being transfered. It can be differnt
325 * sizes at each level of the heirarchy so it belongs in the
326 * packet, not request. This may or may not be populated when a
327 * responder recieves the packet. If not populated it memory should
332 /// The address of the request. This address could be virtual or
333 /// physical, depending on the system configuration.
336 /// True if the request targets the secure memory space.
339 /// The size of the request or transfer.
343 * Track the bytes found that satisfy a functional read.
345 std::vector<bool> bytesValid;
350 * The extra delay from seeing the packet until the header is
351 * transmitted. This delay is used to communicate the crossbar
352 * forwarding latency to the neighbouring object (e.g. a cache)
353 * that actually makes the packet wait. As the delay is relative,
354 * a 32-bit unsigned should be sufficient.
356 uint32_t headerDelay;
359 * Keep track of the extra delay incurred by snooping upwards
360 * before sending a request down the memory system. This is used
361 * by the coherent crossbar to account for the additional request
367 * The extra pipelining delay from seeing the packet until the end of
368 * payload is transmitted by the component that provided it (if
369 * any). This includes the header delay. Similar to the header
370 * delay, this is used to make up for the fact that the
371 * crossbar does not make the packet wait. As the delay is
372 * relative, a 32-bit unsigned should be sufficient.
374 uint32_t payloadDelay;
377 * A virtual base opaque structure used to hold state associated
378 * with the packet (e.g., an MSHR), specific to a MemObject that
379 * sees the packet. A pointer to this state is returned in the
380 * packet's response so that the MemObject in question can quickly
381 * look up the state needed to process it. A specific subclass
382 * would be derived from this to carry state specific to a
383 * particular sending device.
385 * As multiple MemObjects may add their SenderState throughout the
386 * memory system, the SenderStates create a stack, where a
387 * MemObject can add a new Senderstate, as long as the
388 * predecessing SenderState is restored when the response comes
389 * back. For this reason, the predecessor should always be
390 * populated with the current SenderState of a packet before
391 * modifying the senderState field in the request packet.
395 SenderState* predecessor;
396 SenderState() : predecessor(NULL) {}
397 virtual ~SenderState() {}
401 * Object used to maintain state of a PrintReq. The senderState
402 * field of a PrintReq should always be of this type.
404 class PrintReqState : public SenderState
408 * An entry in the label stack.
410 struct LabelStackEntry
412 const std::string label;
415 LabelStackEntry(const std::string &_label, std::string *_prefix);
418 typedef std::list<LabelStackEntry> LabelStack;
419 LabelStack labelStack;
421 std::string *curPrefixPtr;
427 PrintReqState(std::ostream &os, int verbosity = 0);
431 * Returns the current line prefix.
433 const std::string &curPrefix() { return *curPrefixPtr; }
436 * Push a label onto the label stack, and prepend the given
437 * prefix string onto the current prefix. Labels will only be
438 * printed if an object within the label's scope is printed.
440 void pushLabel(const std::string &lbl,
441 const std::string &prefix = " ");
444 * Pop a label off the label stack.
449 * Print all of the pending unprinted labels on the
450 * stack. Called by printObj(), so normally not called by
451 * users unless bypassing printObj().
456 * Print a Printable object to os, because it matched the
457 * address on a PrintReq.
459 void printObj(Printable *obj);
463 * This packet's sender state. Devices should use dynamic_cast<>
464 * to cast to the state appropriate to the sender. The intent of
465 * this variable is to allow a device to attach extra information
466 * to a request. A response packet must return the sender state
467 * that was attached to the original request (even if a new packet
470 SenderState *senderState;
473 * Push a new sender state to the packet and make the current
474 * sender state the predecessor of the new one. This should be
475 * prefered over direct manipulation of the senderState member
478 * @param sender_state SenderState to push at the top of the stack
480 void pushSenderState(SenderState *sender_state);
483 * Pop the top of the state stack and return a pointer to it. This
484 * assumes the current sender state is not NULL. This should be
485 * preferred over direct manipulation of the senderState member
488 * @return The current top of the stack
490 SenderState *popSenderState();
493 * Go through the sender state stack and return the first instance
494 * that is of type T (as determined by a dynamic_cast). If there
495 * is no sender state of type T, NULL is returned.
497 * @return The topmost state of type T
499 template <typename T>
500 T * findNextSenderState() const
503 SenderState* sender_state = senderState;
504 while (t == NULL && sender_state != NULL) {
505 t = dynamic_cast<T*>(sender_state);
506 sender_state = sender_state->predecessor;
511 /// Return the string name of the cmd field (for debugging and
513 const std::string &cmdString() const { return cmd.toString(); }
515 /// Return the index of this command.
516 inline int cmdToIndex() const { return cmd.toInt(); }
518 bool isRead() const { return cmd.isRead(); }
519 bool isWrite() const { return cmd.isWrite(); }
520 bool isUpgrade() const { return cmd.isUpgrade(); }
521 bool isRequest() const { return cmd.isRequest(); }
522 bool isResponse() const { return cmd.isResponse(); }
523 bool needsWritable() const
525 // we should never check if a response needsWritable, the
526 // request has this flag, and for a response we should rather
527 // look at the hasSharers flag (if not set, the response is to
528 // be considered writable)
530 return cmd.needsWritable();
532 bool needsResponse() const { return cmd.needsResponse(); }
533 bool isInvalidate() const { return cmd.isInvalidate(); }
534 bool isEviction() const { return cmd.isEviction(); }
535 bool isClean() const { return cmd.isClean(); }
536 bool fromCache() const { return cmd.fromCache(); }
537 bool isWriteback() const { return cmd.isWriteback(); }
538 bool hasData() const { return cmd.hasData(); }
539 bool hasRespData() const
541 MemCmd resp_cmd = cmd.responseCommand();
542 return resp_cmd.hasData();
544 bool isLLSC() const { return cmd.isLLSC(); }
545 bool isError() const { return cmd.isError(); }
546 bool isPrint() const { return cmd.isPrint(); }
547 bool isFlush() const { return cmd.isFlush(); }
552 * Set the cacheResponding flag. This is used by the caches to
553 * signal another cache that they are responding to a request. A
554 * cache will only respond to snoops if it has the line in either
555 * Modified or Owned state. Note that on snoop hits we always pass
556 * the line as Modified and never Owned. In the case of an Owned
557 * line we proceed to invalidate all other copies.
559 * On a cache fill (see Cache::handleFill), we check hasSharers
560 * first, ignoring the cacheResponding flag if hasSharers is set.
561 * A line is consequently allocated as:
563 * hasSharers cacheResponding state
566 * false false Exclusive
567 * false true Modified
569 void setCacheResponding()
572 assert(!flags.isSet(CACHE_RESPONDING));
573 flags.set(CACHE_RESPONDING);
575 bool cacheResponding() const { return flags.isSet(CACHE_RESPONDING); }
577 * On fills, the hasSharers flag is used by the caches in
578 * combination with the cacheResponding flag, as clarified
579 * above. If the hasSharers flag is not set, the packet is passing
580 * writable. Thus, a response from a memory passes the line as
581 * writable by default.
583 * The hasSharers flag is also used by upstream caches to inform a
584 * downstream cache that they have the block (by calling
585 * setHasSharers on snoop request packets that hit in upstream
586 * cachs tags or MSHRs). If the snoop packet has sharers, a
587 * downstream cache is prevented from passing a dirty line upwards
588 * if it was not explicitly asked for a writable copy. See
589 * Cache::satisfyCpuSideRequest.
591 * The hasSharers flag is also used on writebacks, in
592 * combination with the WritbackClean or WritebackDirty commands,
593 * to allocate the block downstream either as:
595 * command hasSharers state
596 * WritebackDirty false Modified
597 * WritebackDirty true Owned
598 * WritebackClean false Exclusive
599 * WritebackClean true Shared
601 void setHasSharers() { flags.set(HAS_SHARERS); }
602 bool hasSharers() const { return flags.isSet(HAS_SHARERS); }
606 * The express snoop flag is used for two purposes. Firstly, it is
607 * used to bypass flow control for normal (non-snoop) requests
608 * going downstream in the memory system. In cases where a cache
609 * is responding to a snoop from another cache (it had a dirty
610 * line), but the line is not writable (and there are possibly
611 * other copies), the express snoop flag is set by the downstream
612 * cache to invalidate all other copies in zero time. Secondly,
613 * the express snoop flag is also set to be able to distinguish
614 * snoop packets that came from a downstream cache, rather than
615 * snoop packets from neighbouring caches.
617 void setExpressSnoop() { flags.set(EXPRESS_SNOOP); }
618 bool isExpressSnoop() const { return flags.isSet(EXPRESS_SNOOP); }
621 * On responding to a snoop request (which only happens for
622 * Modified or Owned lines), make sure that we can transform an
623 * Owned response to a Modified one. If this flag is not set, the
624 * responding cache had the line in the Owned state, and there are
625 * possibly other Shared copies in the memory system. A downstream
626 * cache helps in orchestrating the invalidation of these copies
627 * by sending out the appropriate express snoops.
629 void setResponderHadWritable()
631 assert(cacheResponding());
632 assert(!responderHadWritable());
633 flags.set(RESPONDER_HAD_WRITABLE);
635 bool responderHadWritable() const
636 { return flags.isSet(RESPONDER_HAD_WRITABLE); }
639 * A writeback/writeclean cmd gets propagated further downstream
640 * by the receiver when the flag is set.
642 void setWriteThrough()
644 assert(cmd.isWrite() &&
645 (cmd.isEviction() || cmd == MemCmd::WriteClean));
646 flags.set(WRITE_THROUGH);
648 void clearWriteThrough() { flags.clear(WRITE_THROUGH); }
649 bool writeThrough() const { return flags.isSet(WRITE_THROUGH); }
652 * Set when a request hits in a cache and the cache is not going
653 * to respond. This is used by the crossbar to coordinate
654 * responses for cache maintenance operations.
658 assert(cmd.isClean());
659 assert(!flags.isSet(SATISFIED));
660 flags.set(SATISFIED);
662 bool satisfied() const { return flags.isSet(SATISFIED); }
664 void setSuppressFuncError() { flags.set(SUPPRESS_FUNC_ERROR); }
665 bool suppressFuncError() const { return flags.isSet(SUPPRESS_FUNC_ERROR); }
666 void setBlockCached() { flags.set(BLOCK_CACHED); }
667 bool isBlockCached() const { return flags.isSet(BLOCK_CACHED); }
668 void clearBlockCached() { flags.clear(BLOCK_CACHED); }
670 // Network error conditions... encapsulate them as methods since
671 // their encoding keeps changing (from result field to command
676 assert(isResponse());
677 cmd = MemCmd::BadAddressError;
680 void copyError(Packet *pkt) { assert(pkt->isError()); cmd = pkt->cmd; }
682 Addr getAddr() const { assert(flags.isSet(VALID_ADDR)); return addr; }
684 * Update the address of this packet mid-transaction. This is used
685 * by the address mapper to change an already set address to a new
686 * one based on the system configuration. It is intended to remap
687 * an existing address, so it asserts that the current address is
690 void setAddr(Addr _addr) { assert(flags.isSet(VALID_ADDR)); addr = _addr; }
692 unsigned getSize() const { assert(flags.isSet(VALID_SIZE)); return size; }
694 Addr getOffset(unsigned int blk_size) const
696 return getAddr() & Addr(blk_size - 1);
699 Addr getBlockAddr(unsigned int blk_size) const
701 return getAddr() & ~(Addr(blk_size - 1));
704 bool isSecure() const
706 assert(flags.isSet(VALID_ADDR));
711 * Accessor function to atomic op.
713 AtomicOpFunctor *getAtomicOp() const { return req->getAtomicOpFunctor(); }
714 bool isAtomicOp() const { return req->isAtomic(); }
717 * It has been determined that the SC packet should successfully update
718 * memory. Therefore, convert this SC packet to a normal write.
725 cmd = MemCmd::WriteReq;
729 * When ruby is in use, Ruby will monitor the cache line and the
730 * phys memory should treat LL ops as normal reads.
737 cmd = MemCmd::ReadReq;
741 * Constructor. Note that a Request object must be constructed
742 * first, but the Requests's physical address and size fields need
743 * not be valid. The command must be supplied.
745 Packet(const RequestPtr _req, MemCmd _cmd)
746 : cmd(_cmd), req(_req), data(nullptr), addr(0), _isSecure(false),
747 size(0), headerDelay(0), snoopDelay(0), payloadDelay(0),
750 if (req->hasPaddr()) {
751 addr = req->getPaddr();
752 flags.set(VALID_ADDR);
753 _isSecure = req->isSecure();
755 if (req->hasSize()) {
756 size = req->getSize();
757 flags.set(VALID_SIZE);
762 * Alternate constructor if you are trying to create a packet with
763 * a request that is for a whole block, not the address from the
764 * req. this allows for overriding the size/addr of the req.
766 Packet(const RequestPtr _req, MemCmd _cmd, int _blkSize)
767 : cmd(_cmd), req(_req), data(nullptr), addr(0), _isSecure(false),
768 headerDelay(0), snoopDelay(0), payloadDelay(0),
771 if (req->hasPaddr()) {
772 addr = req->getPaddr() & ~(_blkSize - 1);
773 flags.set(VALID_ADDR);
774 _isSecure = req->isSecure();
777 flags.set(VALID_SIZE);
781 * Alternate constructor for copying a packet. Copy all fields
782 * *except* if the original packet's data was dynamic, don't copy
783 * that, as we can't guarantee that the new packet's lifetime is
784 * less than that of the original packet. In this case the new
785 * packet should allocate its own data.
787 Packet(const PacketPtr pkt, bool clear_flags, bool alloc_data)
788 : cmd(pkt->cmd), req(pkt->req),
790 addr(pkt->addr), _isSecure(pkt->_isSecure), size(pkt->size),
791 bytesValid(pkt->bytesValid),
792 headerDelay(pkt->headerDelay),
794 payloadDelay(pkt->payloadDelay),
795 senderState(pkt->senderState)
798 flags.set(pkt->flags & COPY_FLAGS);
800 flags.set(pkt->flags & (VALID_ADDR|VALID_SIZE));
802 // should we allocate space for data, or not, the express
803 // snoops do not need to carry any data as they only serve to
804 // co-ordinate state changes
806 // even if asked to allocate data, if the original packet
807 // holds static data, then the sender will not be doing
808 // any memcpy on receiving the response, thus we simply
809 // carry the pointer forward
810 if (pkt->flags.isSet(STATIC_DATA)) {
812 flags.set(STATIC_DATA);
820 * Generate the appropriate read MemCmd based on the Request flags.
823 makeReadCmd(const RequestPtr req)
826 return MemCmd::LoadLockedReq;
827 else if (req->isPrefetch())
828 return MemCmd::SoftPFReq;
830 return MemCmd::ReadReq;
834 * Generate the appropriate write MemCmd based on the Request flags.
837 makeWriteCmd(const RequestPtr req)
840 return MemCmd::StoreCondReq;
841 else if (req->isSwap())
842 return MemCmd::SwapReq;
843 else if (req->isCacheInvalidate()) {
844 return req->isCacheClean() ? MemCmd::CleanInvalidReq :
845 MemCmd::InvalidateReq;
846 } else if (req->isCacheClean()) {
847 return MemCmd::CleanSharedReq;
849 return MemCmd::WriteReq;
853 * Constructor-like methods that return Packets based on Request objects.
854 * Fine-tune the MemCmd type if it's not a vanilla read or write.
857 createRead(const RequestPtr req)
859 return new Packet(req, makeReadCmd(req));
863 createWrite(const RequestPtr req)
865 return new Packet(req, makeWriteCmd(req));
869 * clean up packet variables
873 // Delete the request object if this is a request packet which
874 // does not need a response, because the requester will not get
875 // a chance. If the request packet needs a response then the
876 // request will be deleted on receipt of the response
877 // packet. We also make sure to never delete the request for
878 // express snoops, even for cases when responses are not
879 // needed (CleanEvict and Writeback), since the snoop packet
880 // re-uses the same request.
881 if (req && isRequest() && !needsResponse() &&
889 * Take a request packet and modify it in place to be suitable for
890 * returning as a response to that request.
895 assert(needsResponse());
897 cmd = cmd.responseCommand();
899 // responses are never express, even if the snoop that
900 // triggered them was
901 flags.clear(EXPRESS_SNOOP);
917 setFunctionalResponseStatus(bool success)
921 cmd = MemCmd::FunctionalWriteError;
923 cmd = MemCmd::FunctionalReadError;
929 setSize(unsigned size)
931 assert(!flags.isSet(VALID_SIZE));
934 flags.set(VALID_SIZE);
941 * @name Data accessor mehtods
945 * Set the data pointer to the following value that should not be
946 * freed. Static data allows us to do a single memcpy even if
947 * multiple packets are required to get from source to destination
948 * and back. In essence the pointer is set calling dataStatic on
949 * the original packet, and whenever this packet is copied and
950 * forwarded the same pointer is passed on. When a packet
951 * eventually reaches the destination holding the data, it is
952 * copied once into the location originally set. On the way back
953 * to the source, no copies are necessary.
955 template <typename T>
959 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
960 data = (PacketDataPtr)p;
961 flags.set(STATIC_DATA);
965 * Set the data pointer to the following value that should not be
966 * freed. This version of the function allows the pointer passed
967 * to us to be const. To avoid issues down the line we cast the
968 * constness away, the alternative would be to keep both a const
969 * and non-const data pointer and cleverly choose between
970 * them. Note that this is only allowed for static data.
972 template <typename T>
974 dataStaticConst(const T *p)
976 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
977 data = const_cast<PacketDataPtr>(p);
978 flags.set(STATIC_DATA);
982 * Set the data pointer to a value that should have delete []
983 * called on it. Dynamic data is local to this packet, and as the
984 * packet travels from source to destination, forwarded packets
985 * will allocate their own data. When a packet reaches the final
986 * destination it will populate the dynamic data of that specific
987 * packet, and on the way back towards the source, memcpy will be
988 * invoked in every step where a new packet was created e.g. in
989 * the caches. Ultimately when the response reaches the source a
990 * final memcpy is needed to extract the data from the packet
991 * before it is deallocated.
993 template <typename T>
997 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
998 data = (PacketDataPtr)p;
999 flags.set(DYNAMIC_DATA);
1003 * get a pointer to the data ptr.
1005 template <typename T>
1009 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
1013 template <typename T>
1017 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
1018 return (const T*)data;
1022 * Get the data in the packet byte swapped from big endian to
1025 template <typename T>
1029 * Get the data in the packet byte swapped from little endian to
1032 template <typename T>
1036 * Get the data in the packet byte swapped from the specified
1039 template <typename T>
1040 T get(ByteOrder endian) const;
1043 * Get the data in the packet byte swapped from guest to host
1046 template <typename T>
1049 /** Set the value in the data pointer to v as big endian. */
1050 template <typename T>
1053 /** Set the value in the data pointer to v as little endian. */
1054 template <typename T>
1058 * Set the value in the data pointer to v using the specified
1061 template <typename T>
1062 void set(T v, ByteOrder endian);
1064 /** Set the value in the data pointer to v as guest endian. */
1065 template <typename T>
1069 * Copy data into the packet from the provided pointer.
1072 setData(const uint8_t *p)
1074 // we should never be copying data onto itself, which means we
1075 // must idenfity packets with static data, as they carry the
1076 // same pointer from source to destination and back
1077 assert(p != getPtr<uint8_t>() || flags.isSet(STATIC_DATA));
1079 if (p != getPtr<uint8_t>())
1080 // for packet with allocated dynamic data, we copy data from
1081 // one to the other, e.g. a forwarded response to a response
1082 std::memcpy(getPtr<uint8_t>(), p, getSize());
1086 * Copy data into the packet from the provided block pointer,
1087 * which is aligned to the given block size.
1090 setDataFromBlock(const uint8_t *blk_data, int blkSize)
1092 setData(blk_data + getOffset(blkSize));
1096 * Copy data from the packet to the provided block pointer, which
1097 * is aligned to the given block size.
1100 writeData(uint8_t *p) const
1102 std::memcpy(p, getConstPtr<uint8_t>(), getSize());
1106 * Copy data from the packet to the memory at the provided pointer.
1109 writeDataToBlock(uint8_t *blk_data, int blkSize) const
1111 writeData(blk_data + getOffset(blkSize));
1115 * delete the data pointed to in the data pointer. Ok to call to
1116 * matter how data was allocted.
1121 if (flags.isSet(DYNAMIC_DATA))
1124 flags.clear(STATIC_DATA|DYNAMIC_DATA);
1128 /** Allocate memory for the packet. */
1132 // if either this command or the response command has a data
1133 // payload, actually allocate space
1134 if (hasData() || hasRespData()) {
1135 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
1136 flags.set(DYNAMIC_DATA);
1137 data = new uint8_t[getSize()];
1143 private: // Private data accessor methods
1144 /** Get the data in the packet without byte swapping. */
1145 template <typename T>
1148 /** Set the value in the data pointer to v without byte swapping. */
1149 template <typename T>
1154 * Check a functional request against a memory value stored in
1155 * another packet (i.e. an in-transit request or
1156 * response). Returns true if the current packet is a read, and
1157 * the other packet provides the data, which is then copied to the
1158 * current packet. If the current packet is a write, and the other
1159 * packet intersects this one, then we update the data
1163 checkFunctional(PacketPtr other)
1165 // all packets that are carrying a payload should have a valid
1167 return checkFunctional(other, other->getAddr(), other->isSecure(),
1170 other->getPtr<uint8_t>() : NULL);
1174 * Does the request need to check for cached copies of the same block
1175 * in the memory hierarchy above.
1178 mustCheckAbove() const
1180 return cmd == MemCmd::HardPFReq || isEviction();
1184 * Is this packet a clean eviction, including both actual clean
1185 * evict packets, but also clean writebacks.
1188 isCleanEviction() const
1190 return cmd == MemCmd::CleanEvict || cmd == MemCmd::WritebackClean;
1194 * Check a functional request against a memory value represented
1195 * by a base/size pair and an associated data array. If the
1196 * current packet is a read, it may be satisfied by the memory
1197 * value. If the current packet is a write, it may update the
1201 checkFunctional(Printable *obj, Addr base, bool is_secure, int size,
1205 * Push label for PrintReq (safe to call unconditionally).
1208 pushLabel(const std::string &lbl)
1211 safe_cast<PrintReqState*>(senderState)->pushLabel(lbl);
1215 * Pop label for PrintReq (safe to call unconditionally).
1221 safe_cast<PrintReqState*>(senderState)->popLabel();
1224 void print(std::ostream &o, int verbosity = 0,
1225 const std::string &prefix = "") const;
1228 * A no-args wrapper of print(std::ostream...)
1229 * meant to be invoked from DPRINTFs
1230 * avoiding string overheads in fast mode
1231 * @return string with the request's type and start<->end addresses
1233 std::string print() const;
1236 #endif //__MEM_PACKET_HH