1/*
2 * Copyright (c) 2012-2015 ARM Limited
3 * All rights reserved
4 *
5 * The license below extends only to copyright in the software and shall
6 * not be construed as granting a license to any other intellectual
7 * property including but not limited to intellectual property relating
8 * to a hardware implementation of the functionality of the software
9 * licensed hereunder. You may use the software subject to the license
10 * terms below provided that you ensure that this notice is replicated
11 * unmodified and in its entirety in all distributions of the software,
12 * modified or unmodified, in source code or in binary form.
13 *
14 * Copyright (c) 2006 The Regents of The University of Michigan
15 * Copyright (c) 2010,2015 Advanced Micro Devices, Inc.
16 * All rights reserved.
17 *
18 * Redistribution and use in source and binary forms, with or without
19 * modification, are permitted provided that the following conditions are
20 * met: redistributions of source code must retain the above copyright
21 * notice, this list of conditions and the following disclaimer;
22 * redistributions in binary form must reproduce the above copyright
23 * notice, this list of conditions and the following disclaimer in the
24 * documentation and/or other materials provided with the distribution;
25 * neither the name of the copyright holders nor the names of its
26 * contributors may be used to endorse or promote products derived from
27 * this software without specific prior written permission.
28 *
29 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
30 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
31 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
32 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
33 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
34 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
35 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
39 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
40 *
41 * Authors: Ron Dreslinski
42 * Steve Reinhardt
43 * Ali Saidi
44 * Andreas Hansson
45 */
46
47/**
48 * @file
49 * Declaration of the Packet class.
50 */
51
52#ifndef __MEM_PACKET_HH__
53#define __MEM_PACKET_HH__
54
55#include <bitset>
56#include <cassert>
57#include <list>
58
59#include "base/cast.hh"
60#include "base/compiler.hh"
61#include "base/flags.hh"
62#include "base/misc.hh"
63#include "base/printable.hh"
64#include "base/types.hh"
65#include "mem/request.hh"
66#include "sim/core.hh"
67
68class Packet;
69typedef Packet *PacketPtr;
70typedef uint8_t* PacketDataPtr;
71typedef std::list<PacketPtr> PacketList;
72
73class MemCmd
74{
75 friend class Packet;
76
77 public:
78 /**
79 * List of all commands associated with a packet.
80 */
81 enum Command
82 {
83 InvalidCmd,
84 ReadReq,
85 ReadResp,
86 ReadRespWithInvalidate,
87 WriteReq,
88 WriteResp,
89 Writeback,
90 CleanEvict,
91 SoftPFReq,
92 HardPFReq,
93 SoftPFResp,
94 HardPFResp,
95 WriteLineReq,
96 UpgradeReq,
97 SCUpgradeReq, // Special "weak" upgrade for StoreCond
98 UpgradeResp,
99 SCUpgradeFailReq, // Failed SCUpgradeReq in MSHR (never sent)
100 UpgradeFailResp, // Valid for SCUpgradeReq only
101 ReadExReq,
102 ReadExResp,
103 ReadCleanReq,
104 ReadSharedReq,
105 LoadLockedReq,
106 StoreCondReq,
107 StoreCondFailReq, // Failed StoreCondReq in MSHR (never sent)
108 StoreCondResp,
109 SwapReq,
110 SwapResp,
111 MessageReq,
112 MessageResp,
113 ReleaseReq,
114 ReleaseResp,
115 AcquireReq,
116 AcquireResp,
117 // Error responses
118 // @TODO these should be classified as responses rather than
119 // requests; coding them as requests initially for backwards
120 // compatibility
121 InvalidDestError, // packet dest field invalid
122 BadAddressError, // memory address invalid
123 FunctionalReadError, // unable to fulfill functional read
124 FunctionalWriteError, // unable to fulfill functional write
125 // Fake simulator-only commands
126 PrintReq, // Print state matching address
127 FlushReq, //request for a cache flush
128 InvalidateReq, // request for address to be invalidated
129 InvalidateResp,
130 NUM_MEM_CMDS
131 };
132
133 private:
134 /**
135 * List of command attributes.
136 */
137 enum Attribute
138 {
139 IsRead, //!< Data flows from responder to requester
140 IsWrite, //!< Data flows from requester to responder
141 IsUpgrade,
142 IsInvalidate,
143 NeedsExclusive, //!< Requires exclusive copy to complete in-cache
144 IsRequest, //!< Issued by requester
145 IsResponse, //!< Issue by responder
146 NeedsResponse, //!< Requester needs response from target
147 IsSWPrefetch,
148 IsHWPrefetch,
149 IsLlsc, //!< Alpha/MIPS LL or SC access
150 HasData, //!< There is an associated payload
151 IsError, //!< Error response
152 IsPrint, //!< Print state matching address (for debugging)
153 IsFlush, //!< Flush the address from caches
154 NUM_COMMAND_ATTRIBUTES
155 };
156
157 /**
158 * Structure that defines attributes and other data associated
159 * with a Command.
160 */
161 struct CommandInfo
162 {
163 /// Set of attribute flags.
164 const std::bitset<NUM_COMMAND_ATTRIBUTES> attributes;
165 /// Corresponding response for requests; InvalidCmd if no
166 /// response is applicable.
167 const Command response;
168 /// String representation (for printing)
169 const std::string str;
170 };
171
172 /// Array to map Command enum to associated info.
173 static const CommandInfo commandInfo[];
174
175 private:
176
177 Command cmd;
178
179 bool
180 testCmdAttrib(MemCmd::Attribute attrib) const
181 {
182 return commandInfo[cmd].attributes[attrib] != 0;
183 }
184
185 public:
186
187 bool isRead() const { return testCmdAttrib(IsRead); }
188 bool isWrite() const { return testCmdAttrib(IsWrite); }
189 bool isUpgrade() const { return testCmdAttrib(IsUpgrade); }
190 bool isRequest() const { return testCmdAttrib(IsRequest); }
191 bool isResponse() const { return testCmdAttrib(IsResponse); }
192 bool needsExclusive() const { return testCmdAttrib(NeedsExclusive); }
193 bool needsResponse() const { return testCmdAttrib(NeedsResponse); }
194 bool isInvalidate() const { return testCmdAttrib(IsInvalidate); }
195
196 /**
197 * Check if this particular packet type carries payload data. Note
198 * that this does not reflect if the data pointer of the packet is
199 * valid or not.
200 */
201 bool hasData() const { return testCmdAttrib(HasData); }
202 bool isLLSC() const { return testCmdAttrib(IsLlsc); }
203 bool isSWPrefetch() const { return testCmdAttrib(IsSWPrefetch); }
204 bool isHWPrefetch() const { return testCmdAttrib(IsHWPrefetch); }
205 bool isPrefetch() const { return testCmdAttrib(IsSWPrefetch) ||
206 testCmdAttrib(IsHWPrefetch); }
207 bool isError() const { return testCmdAttrib(IsError); }
208 bool isPrint() const { return testCmdAttrib(IsPrint); }
209 bool isFlush() const { return testCmdAttrib(IsFlush); }
210
211 const Command
212 responseCommand() const
213 {
214 return commandInfo[cmd].response;
215 }
216
217 /// Return the string to a cmd given by idx.
218 const std::string &toString() const { return commandInfo[cmd].str; }
219 int toInt() const { return (int)cmd; }
220
221 MemCmd(Command _cmd) : cmd(_cmd) { }
222 MemCmd(int _cmd) : cmd((Command)_cmd) { }
223 MemCmd() : cmd(InvalidCmd) { }
224
225 bool operator==(MemCmd c2) const { return (cmd == c2.cmd); }
226 bool operator!=(MemCmd c2) const { return (cmd != c2.cmd); }
227};
228
229/**
230 * A Packet is used to encapsulate a transfer between two objects in
231 * the memory system (e.g., the L1 and L2 cache). (In contrast, a
232 * single Request travels all the way from the requester to the
233 * ultimate destination and back, possibly being conveyed by several
234 * different Packets along the way.)
235 */
236class Packet : public Printable
237{
238 public:
239 typedef uint32_t FlagsType;
240 typedef ::Flags<FlagsType> Flags;
241
242 private:
243
244 enum : FlagsType {
245 // Flags to transfer across when copying a packet
246 COPY_FLAGS = 0x0000000F,
247
248 SHARED = 0x00000001,
249 // Special control flags
250 /// Special timing-mode atomic snoop for multi-level coherence.
251 EXPRESS_SNOOP = 0x00000002,
252 /// Does supplier have exclusive copy?
253 /// Useful for multi-level coherence.
254 SUPPLY_EXCLUSIVE = 0x00000004,
255 // Snoop response flags
256 MEM_INHIBIT = 0x00000008,
257
258 /// Are the 'addr' and 'size' fields valid?
259 VALID_ADDR = 0x00000100,
260 VALID_SIZE = 0x00000200,
261
262 /// Is the data pointer set to a value that shouldn't be freed
263 /// when the packet is destroyed?
264 STATIC_DATA = 0x00001000,
265 /// The data pointer points to a value that should be freed when
266 /// the packet is destroyed. The pointer is assumed to be pointing
267 /// to an array, and delete [] is consequently called
268 DYNAMIC_DATA = 0x00002000,
269
270 /// suppress the error if this packet encounters a functional
271 /// access failure.
272 SUPPRESS_FUNC_ERROR = 0x00008000,
273
274 // Signal block present to squash prefetch and cache evict packets
275 // through express snoop flag
276 BLOCK_CACHED = 0x00010000
277 };
278
279 Flags flags;
280
281 public:
282 typedef MemCmd::Command Command;
283
284 /// The command field of the packet.
285 MemCmd cmd;
286
287 /// A pointer to the original request.
288 const RequestPtr req;
289
290 private:
291 /**
292 * A pointer to the data being transfered. It can be differnt
293 * sizes at each level of the heirarchy so it belongs in the
294 * packet, not request. This may or may not be populated when a
295 * responder recieves the packet. If not populated it memory should
296 * be allocated.
297 */
298 PacketDataPtr data;
299
300 /// The address of the request. This address could be virtual or
301 /// physical, depending on the system configuration.
302 Addr addr;
303
304 /// True if the request targets the secure memory space.
305 bool _isSecure;
306
307 /// The size of the request or transfer.
308 unsigned size;
309
310 /**
311 * Track the bytes found that satisfy a functional read.
312 */
313 std::vector<bool> bytesValid;
314
315 public:
316
317 /**
318 * The extra delay from seeing the packet until the header is
319 * transmitted. This delay is used to communicate the crossbar
320 * forwarding latency to the neighbouring object (e.g. a cache)
321 * that actually makes the packet wait. As the delay is relative,
322 * a 32-bit unsigned should be sufficient.
323 */
324 uint32_t headerDelay;
325
326 /**
327 * The extra pipelining delay from seeing the packet until the end of
328 * payload is transmitted by the component that provided it (if
329 * any). This includes the header delay. Similar to the header
330 * delay, this is used to make up for the fact that the
331 * crossbar does not make the packet wait. As the delay is
332 * relative, a 32-bit unsigned should be sufficient.
333 */
334 uint32_t payloadDelay;
335
336 /**
337 * A virtual base opaque structure used to hold state associated
338 * with the packet (e.g., an MSHR), specific to a MemObject that
339 * sees the packet. A pointer to this state is returned in the
340 * packet's response so that the MemObject in question can quickly
341 * look up the state needed to process it. A specific subclass
342 * would be derived from this to carry state specific to a
343 * particular sending device.
344 *
345 * As multiple MemObjects may add their SenderState throughout the
346 * memory system, the SenderStates create a stack, where a
347 * MemObject can add a new Senderstate, as long as the
348 * predecessing SenderState is restored when the response comes
349 * back. For this reason, the predecessor should always be
350 * populated with the current SenderState of a packet before
351 * modifying the senderState field in the request packet.
352 */
353 struct SenderState
354 {
355 SenderState* predecessor;
356 SenderState() : predecessor(NULL) {}
357 virtual ~SenderState() {}
358 };
359
360 /**
361 * Object used to maintain state of a PrintReq. The senderState
362 * field of a PrintReq should always be of this type.
363 */
364 class PrintReqState : public SenderState
365 {
366 private:
367 /**
368 * An entry in the label stack.
369 */
370 struct LabelStackEntry
371 {
372 const std::string label;
373 std::string *prefix;
374 bool labelPrinted;
375 LabelStackEntry(const std::string &_label, std::string *_prefix);
376 };
377
378 typedef std::list<LabelStackEntry> LabelStack;
379 LabelStack labelStack;
380
381 std::string *curPrefixPtr;
382
383 public:
384 std::ostream &os;
385 const int verbosity;
386
387 PrintReqState(std::ostream &os, int verbosity = 0);
388 ~PrintReqState();
389
390 /**
391 * Returns the current line prefix.
392 */
393 const std::string &curPrefix() { return *curPrefixPtr; }
394
395 /**
396 * Push a label onto the label stack, and prepend the given
397 * prefix string onto the current prefix. Labels will only be
398 * printed if an object within the label's scope is printed.
399 */
400 void pushLabel(const std::string &lbl,
401 const std::string &prefix = " ");
402
403 /**
404 * Pop a label off the label stack.
405 */
406 void popLabel();
407
408 /**
409 * Print all of the pending unprinted labels on the
410 * stack. Called by printObj(), so normally not called by
411 * users unless bypassing printObj().
412 */
413 void printLabels();
414
415 /**
416 * Print a Printable object to os, because it matched the
417 * address on a PrintReq.
418 */
419 void printObj(Printable *obj);
420 };
421
422 /**
423 * This packet's sender state. Devices should use dynamic_cast<>
424 * to cast to the state appropriate to the sender. The intent of
425 * this variable is to allow a device to attach extra information
426 * to a request. A response packet must return the sender state
427 * that was attached to the original request (even if a new packet
428 * is created).
429 */
430 SenderState *senderState;
431
432 /**
433 * Push a new sender state to the packet and make the current
434 * sender state the predecessor of the new one. This should be
435 * prefered over direct manipulation of the senderState member
436 * variable.
437 *
438 * @param sender_state SenderState to push at the top of the stack
439 */
440 void pushSenderState(SenderState *sender_state);
441
442 /**
443 * Pop the top of the state stack and return a pointer to it. This
444 * assumes the current sender state is not NULL. This should be
445 * preferred over direct manipulation of the senderState member
446 * variable.
447 *
448 * @return The current top of the stack
449 */
450 SenderState *popSenderState();
451
452 /**
453 * Go through the sender state stack and return the first instance
454 * that is of type T (as determined by a dynamic_cast). If there
455 * is no sender state of type T, NULL is returned.
456 *
457 * @return The topmost state of type T
458 */
459 template <typename T>
460 T * findNextSenderState() const
461 {
462 T *t = NULL;
463 SenderState* sender_state = senderState;
464 while (t == NULL && sender_state != NULL) {
465 t = dynamic_cast<T*>(sender_state);
466 sender_state = sender_state->predecessor;
467 }
468 return t;
469 }
470
471 /// Return the string name of the cmd field (for debugging and
472 /// tracing).
473 const std::string &cmdString() const { return cmd.toString(); }
474
475 /// Return the index of this command.
476 inline int cmdToIndex() const { return cmd.toInt(); }
477
478 bool isRead() const { return cmd.isRead(); }
479 bool isWrite() const { return cmd.isWrite(); }
480 bool isUpgrade() const { return cmd.isUpgrade(); }
481 bool isRequest() const { return cmd.isRequest(); }
482 bool isResponse() const { return cmd.isResponse(); }
483 bool needsExclusive() const { return cmd.needsExclusive(); }
484 bool needsResponse() const { return cmd.needsResponse(); }
485 bool isInvalidate() const { return cmd.isInvalidate(); }
486 bool hasData() const { return cmd.hasData(); }
487 bool isLLSC() const { return cmd.isLLSC(); }
488 bool isError() const { return cmd.isError(); }
489 bool isPrint() const { return cmd.isPrint(); }
490 bool isFlush() const { return cmd.isFlush(); }
491
492 // Snoop flags
493 void assertMemInhibit()
494 {
495 assert(isRequest());
496 assert(!flags.isSet(MEM_INHIBIT));
497 flags.set(MEM_INHIBIT);
498 }
499 bool memInhibitAsserted() const { return flags.isSet(MEM_INHIBIT); }
500 void assertShared() { flags.set(SHARED); }
501 bool sharedAsserted() const { return flags.isSet(SHARED); }
502
503 // Special control flags
504 void setExpressSnoop() { flags.set(EXPRESS_SNOOP); }
505 bool isExpressSnoop() const { return flags.isSet(EXPRESS_SNOOP); }
506 void setSupplyExclusive() { flags.set(SUPPLY_EXCLUSIVE); }
507 bool isSupplyExclusive() const { return flags.isSet(SUPPLY_EXCLUSIVE); }
508 void setSuppressFuncError() { flags.set(SUPPRESS_FUNC_ERROR); }
509 bool suppressFuncError() const { return flags.isSet(SUPPRESS_FUNC_ERROR); }
510 void setBlockCached() { flags.set(BLOCK_CACHED); }
511 bool isBlockCached() const { return flags.isSet(BLOCK_CACHED); }
512 void clearBlockCached() { flags.clear(BLOCK_CACHED); }
513
514 // Network error conditions... encapsulate them as methods since
515 // their encoding keeps changing (from result field to command
516 // field, etc.)
517 void
518 setBadAddress()
519 {
520 assert(isResponse());
521 cmd = MemCmd::BadAddressError;
522 }
523
524 void copyError(Packet *pkt) { assert(pkt->isError()); cmd = pkt->cmd; }
525
526 Addr getAddr() const { assert(flags.isSet(VALID_ADDR)); return addr; }
527 /**
528 * Update the address of this packet mid-transaction. This is used
529 * by the address mapper to change an already set address to a new
530 * one based on the system configuration. It is intended to remap
531 * an existing address, so it asserts that the current address is
532 * valid.
533 */
534 void setAddr(Addr _addr) { assert(flags.isSet(VALID_ADDR)); addr = _addr; }
535
536 unsigned getSize() const { assert(flags.isSet(VALID_SIZE)); return size; }
537
538 Addr getOffset(unsigned int blk_size) const
539 {
540 return getAddr() & Addr(blk_size - 1);
541 }
542
543 Addr getBlockAddr(unsigned int blk_size) const
544 {
545 return getAddr() & ~(Addr(blk_size - 1));
546 }
547
548 bool isSecure() const
549 {
550 assert(flags.isSet(VALID_ADDR));
551 return _isSecure;
552 }
553
554 /**
555 * It has been determined that the SC packet should successfully update
556 * memory. Therefore, convert this SC packet to a normal write.
557 */
558 void
559 convertScToWrite()
560 {
561 assert(isLLSC());
562 assert(isWrite());
563 cmd = MemCmd::WriteReq;
564 }
565
566 /**
567 * When ruby is in use, Ruby will monitor the cache line and the
568 * phys memory should treat LL ops as normal reads.
569 */
570 void
571 convertLlToRead()
572 {
573 assert(isLLSC());
574 assert(isRead());
575 cmd = MemCmd::ReadReq;
576 }
577
578 /**
579 * Constructor. Note that a Request object must be constructed
580 * first, but the Requests's physical address and size fields need
581 * not be valid. The command must be supplied.
582 */
583 Packet(const RequestPtr _req, MemCmd _cmd)
584 : cmd(_cmd), req(_req), data(nullptr), addr(0), _isSecure(false),
585 size(0), headerDelay(0), payloadDelay(0),
586 senderState(NULL)
587 {
588 if (req->hasPaddr()) {
589 addr = req->getPaddr();
590 flags.set(VALID_ADDR);
591 _isSecure = req->isSecure();
592 }
593 if (req->hasSize()) {
594 size = req->getSize();
595 flags.set(VALID_SIZE);
596 }
597 }
598
599 /**
600 * Alternate constructor if you are trying to create a packet with
601 * a request that is for a whole block, not the address from the
602 * req. this allows for overriding the size/addr of the req.
603 */
604 Packet(const RequestPtr _req, MemCmd _cmd, int _blkSize)
605 : cmd(_cmd), req(_req), data(nullptr), addr(0), _isSecure(false),
606 headerDelay(0), payloadDelay(0),
607 senderState(NULL)
608 {
609 if (req->hasPaddr()) {
610 addr = req->getPaddr() & ~(_blkSize - 1);
611 flags.set(VALID_ADDR);
612 _isSecure = req->isSecure();
613 }
614 size = _blkSize;
615 flags.set(VALID_SIZE);
616 }
617
618 /**
619 * Alternate constructor for copying a packet. Copy all fields
620 * *except* if the original packet's data was dynamic, don't copy
621 * that, as we can't guarantee that the new packet's lifetime is
622 * less than that of the original packet. In this case the new
623 * packet should allocate its own data.
624 */
625 Packet(const PacketPtr pkt, bool clear_flags, bool alloc_data)
626 : cmd(pkt->cmd), req(pkt->req),
627 data(nullptr),
628 addr(pkt->addr), _isSecure(pkt->_isSecure), size(pkt->size),
629 bytesValid(pkt->bytesValid),
630 headerDelay(pkt->headerDelay),
631 payloadDelay(pkt->payloadDelay),
632 senderState(pkt->senderState)
633 {
634 if (!clear_flags)
635 flags.set(pkt->flags & COPY_FLAGS);
636
637 flags.set(pkt->flags & (VALID_ADDR|VALID_SIZE));
638
639 // should we allocate space for data, or not, the express
640 // snoops do not need to carry any data as they only serve to
641 // co-ordinate state changes
642 if (alloc_data) {
643 // even if asked to allocate data, if the original packet
644 // holds static data, then the sender will not be doing
645 // any memcpy on receiving the response, thus we simply
646 // carry the pointer forward
647 if (pkt->flags.isSet(STATIC_DATA)) {
648 data = pkt->data;
649 flags.set(STATIC_DATA);
650 } else {
651 allocate();
652 }
653 }
654 }
655
656 /**
657 * Generate the appropriate read MemCmd based on the Request flags.
658 */
659 static MemCmd
660 makeReadCmd(const RequestPtr req)
661 {
662 if (req->isLLSC())
663 return MemCmd::LoadLockedReq;
664 else if (req->isPrefetch())
665 return MemCmd::SoftPFReq;
666 else
667 return MemCmd::ReadReq;
668 }
669
670 /**
671 * Generate the appropriate write MemCmd based on the Request flags.
672 */
673 static MemCmd
674 makeWriteCmd(const RequestPtr req)
675 {
676 if (req->isLLSC())
677 return MemCmd::StoreCondReq;
678 else if (req->isSwap())
679 return MemCmd::SwapReq;
680 else
681 return MemCmd::WriteReq;
682 }
683
684 /**
685 * Constructor-like methods that return Packets based on Request objects.
686 * Fine-tune the MemCmd type if it's not a vanilla read or write.
687 */
688 static PacketPtr
689 createRead(const RequestPtr req)
690 {
691 return new Packet(req, makeReadCmd(req));
692 }
693
694 static PacketPtr
695 createWrite(const RequestPtr req)
696 {
697 return new Packet(req, makeWriteCmd(req));
698 }
699
700 /**
701 * clean up packet variables
702 */
703 ~Packet()
704 {
705 // Delete the request object if this is a request packet which
706 // does not need a response, because the requester will not get
707 // a chance. If the request packet needs a response then the
708 // request will be deleted on receipt of the response
709 // packet. We also make sure to never delete the request for
710 // express snoops, even for cases when responses are not
711 // needed (CleanEvict and Writeback), since the snoop packet
712 // re-uses the same request.
713 if (req && isRequest() && !needsResponse() &&
714 !isExpressSnoop()) {
715 delete req;
716 }
717 deleteData();
718 }
719
720 /**
721 * Take a request packet and modify it in place to be suitable for
722 * returning as a response to that request.
723 */
724 void
725 makeResponse()
726 {
727 assert(needsResponse());
728 assert(isRequest());
729 cmd = cmd.responseCommand();
730
731 // responses are never express, even if the snoop that
732 // triggered them was
733 flags.clear(EXPRESS_SNOOP);
734 }
735
736 void
737 makeAtomicResponse()
738 {
739 makeResponse();
740 }
741
742 void
743 makeTimingResponse()
744 {
745 makeResponse();
746 }
747
748 void
749 setFunctionalResponseStatus(bool success)
750 {
751 if (!success) {
752 if (isWrite()) {
753 cmd = MemCmd::FunctionalWriteError;
754 } else {
755 cmd = MemCmd::FunctionalReadError;
756 }
757 }
758 }
759
760 void
761 setSize(unsigned size)
762 {
763 assert(!flags.isSet(VALID_SIZE));
764
765 this->size = size;
766 flags.set(VALID_SIZE);
767 }
768
769
770 public:
771 /**
772 * @{
773 * @name Data accessor mehtods
774 */
775
776 /**
777 * Set the data pointer to the following value that should not be
778 * freed. Static data allows us to do a single memcpy even if
779 * multiple packets are required to get from source to destination
780 * and back. In essence the pointer is set calling dataStatic on
781 * the original packet, and whenever this packet is copied and
782 * forwarded the same pointer is passed on. When a packet
783 * eventually reaches the destination holding the data, it is
784 * copied once into the location originally set. On the way back
785 * to the source, no copies are necessary.
786 */
787 template <typename T>
788 void
789 dataStatic(T *p)
790 {
791 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
792 data = (PacketDataPtr)p;
793 flags.set(STATIC_DATA);
794 }
795
796 /**
797 * Set the data pointer to the following value that should not be
798 * freed. This version of the function allows the pointer passed
799 * to us to be const. To avoid issues down the line we cast the
800 * constness away, the alternative would be to keep both a const
801 * and non-const data pointer and cleverly choose between
802 * them. Note that this is only allowed for static data.
803 */
804 template <typename T>
805 void
806 dataStaticConst(const T *p)
807 {
808 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
809 data = const_cast<PacketDataPtr>(p);
810 flags.set(STATIC_DATA);
811 }
812
813 /**
814 * Set the data pointer to a value that should have delete []
815 * called on it. Dynamic data is local to this packet, and as the
816 * packet travels from source to destination, forwarded packets
817 * will allocate their own data. When a packet reaches the final
818 * destination it will populate the dynamic data of that specific
819 * packet, and on the way back towards the source, memcpy will be
820 * invoked in every step where a new packet was created e.g. in
821 * the caches. Ultimately when the response reaches the source a
822 * final memcpy is needed to extract the data from the packet
823 * before it is deallocated.
824 */
825 template <typename T>
826 void
827 dataDynamic(T *p)
828 {
829 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
830 data = (PacketDataPtr)p;
831 flags.set(DYNAMIC_DATA);
832 }
833
834 /**
835 * get a pointer to the data ptr.
836 */
837 template <typename T>
838 T*
839 getPtr()
840 {
841 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
842 return (T*)data;
843 }
844
845 template <typename T>
846 const T*
847 getConstPtr() const
848 {
849 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
850 return (const T*)data;
851 }
852
853 /**
854 * Get the data in the packet byte swapped from big endian to
855 * host endian.
856 */
857 template <typename T>
858 T getBE() const;
859
860 /**
861 * Get the data in the packet byte swapped from little endian to
862 * host endian.
863 */
864 template <typename T>
865 T getLE() const;
866
867 /**
868 * Get the data in the packet byte swapped from the specified
869 * endianness.
870 */
871 template <typename T>
872 T get(ByteOrder endian) const;
873
874 /**
875 * Get the data in the packet byte swapped from guest to host
876 * endian.
877 */
878 template <typename T>
879 T get() const;
880
881 /** Set the value in the data pointer to v as big endian. */
882 template <typename T>
883 void setBE(T v);
884
885 /** Set the value in the data pointer to v as little endian. */
886 template <typename T>
887 void setLE(T v);
888
889 /**
890 * Set the value in the data pointer to v using the specified
891 * endianness.
892 */
893 template <typename T>
894 void set(T v, ByteOrder endian);
895
896 /** Set the value in the data pointer to v as guest endian. */
897 template <typename T>
898 void set(T v);
899
900 /**
901 * Copy data into the packet from the provided pointer.
902 */
903 void
904 setData(const uint8_t *p)
905 {
906 // we should never be copying data onto itself, which means we
907 // must idenfity packets with static data, as they carry the
908 // same pointer from source to destination and back
909 assert(p != getPtr<uint8_t>() || flags.isSet(STATIC_DATA));
910
911 if (p != getPtr<uint8_t>())
912 // for packet with allocated dynamic data, we copy data from
913 // one to the other, e.g. a forwarded response to a response
914 std::memcpy(getPtr<uint8_t>(), p, getSize());
915 }
916
917 /**
918 * Copy data into the packet from the provided block pointer,
919 * which is aligned to the given block size.
920 */
921 void
922 setDataFromBlock(const uint8_t *blk_data, int blkSize)
923 {
924 setData(blk_data + getOffset(blkSize));
925 }
926
927 /**
928 * Copy data from the packet to the provided block pointer, which
929 * is aligned to the given block size.
930 */
931 void
932 writeData(uint8_t *p) const
933 {
934 std::memcpy(p, getConstPtr<uint8_t>(), getSize());
935 }
936
937 /**
938 * Copy data from the packet to the memory at the provided pointer.
939 */
940 void
941 writeDataToBlock(uint8_t *blk_data, int blkSize) const
942 {
943 writeData(blk_data + getOffset(blkSize));
944 }
945
946 /**
947 * delete the data pointed to in the data pointer. Ok to call to
948 * matter how data was allocted.
949 */
950 void
951 deleteData()
952 {
953 if (flags.isSet(DYNAMIC_DATA))
954 delete [] data;
955
956 flags.clear(STATIC_DATA|DYNAMIC_DATA);
957 data = NULL;
958 }
959
960 /** Allocate memory for the packet. */
961 void
962 allocate()
963 {
964 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
965 flags.set(DYNAMIC_DATA);
966 data = new uint8_t[getSize()];
967 }
968
969 /** @} */
970
971 private: // Private data accessor methods
972 /** Get the data in the packet without byte swapping. */
973 template <typename T>
974 T getRaw() const;
975
976 /** Set the value in the data pointer to v without byte swapping. */
977 template <typename T>
978 void setRaw(T v);
979
980 public:
981 /**
982 * Check a functional request against a memory value stored in
983 * another packet (i.e. an in-transit request or
984 * response). Returns true if the current packet is a read, and
985 * the other packet provides the data, which is then copied to the
986 * current packet. If the current packet is a write, and the other
987 * packet intersects this one, then we update the data
988 * accordingly.
989 */
990 bool
991 checkFunctional(PacketPtr other)
992 {
993 // all packets that are carrying a payload should have a valid
994 // data pointer
995 return checkFunctional(other, other->getAddr(), other->isSecure(),
996 other->getSize(),
997 other->hasData() ?
998 other->getPtr<uint8_t>() : NULL);
999 }
1000
1001 /**
1002 * Is this request notification of a clean or dirty eviction from the cache.
1003 **/
1004 bool
1005 evictingBlock() const
1006 {
1007 return (cmd == MemCmd::Writeback ||
1008 cmd == MemCmd::CleanEvict);
1009 }
1010
1011 /**
1012 * Does the request need to check for cached copies of the same block
1013 * in the memory hierarchy above.
1014 **/
1015 bool
1016 mustCheckAbove() const
1017 {
1018 return (cmd == MemCmd::HardPFReq ||
1019 evictingBlock());
1020 }
1021
1022 /**
1023 * Check a functional request against a memory value represented
1024 * by a base/size pair and an associated data array. If the
1025 * current packet is a read, it may be satisfied by the memory
1026 * value. If the current packet is a write, it may update the
1027 * memory value.
1028 */
1029 bool
1030 checkFunctional(Printable *obj, Addr base, bool is_secure, int size,
1031 uint8_t *_data);
1032
1033 /**
1034 * Push label for PrintReq (safe to call unconditionally).
1035 */
1036 void
1037 pushLabel(const std::string &lbl)
1038 {
1039 if (isPrint())
1040 safe_cast<PrintReqState*>(senderState)->pushLabel(lbl);
1041 }
1042
1043 /**
1044 * Pop label for PrintReq (safe to call unconditionally).
1045 */
1046 void
1047 popLabel()
1048 {
1049 if (isPrint())
1050 safe_cast<PrintReqState*>(senderState)->popLabel();
1051 }
1052
1053 void print(std::ostream &o, int verbosity = 0,
1054 const std::string &prefix = "") const;
1055
1056 /**
1057 * A no-args wrapper of print(std::ostream...)
1058 * meant to be invoked from DPRINTFs
1059 * avoiding string overheads in fast mode
1060 * @return string with the request's type and start<->end addresses
1061 */
1062 std::string print() const;
1063};
1064
1065#endif //__MEM_PACKET_HH