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 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 SoftPFReq,
91 HardPFReq,
92 SoftPFResp,
93 HardPFResp,
94 WriteInvalidateReq,
95 WriteInvalidateResp,
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 LoadLockedReq,
104 StoreCondReq,
105 StoreCondFailReq, // Failed StoreCondReq in MSHR (never sent)
106 StoreCondResp,
107 SwapReq,
108 SwapResp,
109 MessageReq,
110 MessageResp,
111 // Error responses
112 // @TODO these should be classified as responses rather than
113 // requests; coding them as requests initially for backwards
114 // compatibility
115 InvalidDestError, // packet dest field invalid
116 BadAddressError, // memory address invalid
117 FunctionalReadError, // unable to fulfill functional read
118 FunctionalWriteError, // unable to fulfill functional write
119 // Fake simulator-only commands
120 PrintReq, // Print state matching address
121 FlushReq, //request for a cache flush
122 InvalidationReq, // request for address to be invalidated from lsq
123 NUM_MEM_CMDS
124 };
125
126 private:
127 /**
128 * List of command attributes.
129 */
130 enum Attribute
131 {
132 IsRead, //!< Data flows from responder to requester
133 IsWrite, //!< Data flows from requester to responder
134 IsUpgrade,
135 IsInvalidate,
136 NeedsExclusive, //!< Requires exclusive copy to complete in-cache
137 IsRequest, //!< Issued by requester
138 IsResponse, //!< Issue by responder
139 NeedsResponse, //!< Requester needs response from target
140 IsSWPrefetch,
141 IsHWPrefetch,
142 IsLlsc, //!< Alpha/MIPS LL or SC access
143 HasData, //!< There is an associated payload
144 IsError, //!< Error response
145 IsPrint, //!< Print state matching address (for debugging)
146 IsFlush, //!< Flush the address from caches
147 NUM_COMMAND_ATTRIBUTES
148 };
149
150 /**
151 * Structure that defines attributes and other data associated
152 * with a Command.
153 */
154 struct CommandInfo
155 {
156 /// Set of attribute flags.
157 const std::bitset<NUM_COMMAND_ATTRIBUTES> attributes;
158 /// Corresponding response for requests; InvalidCmd if no
159 /// response is applicable.
160 const Command response;
161 /// String representation (for printing)
162 const std::string str;
163 };
164
165 /// Array to map Command enum to associated info.
166 static const CommandInfo commandInfo[];
167
168 private:
169
170 Command cmd;
171
172 bool
173 testCmdAttrib(MemCmd::Attribute attrib) const
174 {
175 return commandInfo[cmd].attributes[attrib] != 0;
176 }
177
178 public:
179
180 bool isRead() const { return testCmdAttrib(IsRead); }
181 bool isWrite() const { return testCmdAttrib(IsWrite); }
182 bool isUpgrade() const { return testCmdAttrib(IsUpgrade); }
183 bool isRequest() const { return testCmdAttrib(IsRequest); }
184 bool isResponse() const { return testCmdAttrib(IsResponse); }
185 bool needsExclusive() const { return testCmdAttrib(NeedsExclusive); }
186 bool needsResponse() const { return testCmdAttrib(NeedsResponse); }
187 bool isInvalidate() const { return testCmdAttrib(IsInvalidate); }
188 bool isWriteInvalidate() const { return testCmdAttrib(IsWrite) &&
189 testCmdAttrib(IsInvalidate); }
190
191 /**
192 * Check if this particular packet type carries payload data. Note
193 * that this does not reflect if the data pointer of the packet is
194 * valid or not.
195 */
196 bool hasData() const { return testCmdAttrib(HasData); }
197 bool isLLSC() const { return testCmdAttrib(IsLlsc); }
198 bool isSWPrefetch() const { return testCmdAttrib(IsSWPrefetch); }
199 bool isHWPrefetch() const { return testCmdAttrib(IsHWPrefetch); }
200 bool isPrefetch() const { return testCmdAttrib(IsSWPrefetch) ||
201 testCmdAttrib(IsHWPrefetch); }
202 bool isError() const { return testCmdAttrib(IsError); }
203 bool isPrint() const { return testCmdAttrib(IsPrint); }
204 bool isFlush() const { return testCmdAttrib(IsFlush); }
205
206 const Command
207 responseCommand() const
208 {
209 return commandInfo[cmd].response;
210 }
211
212 /// Return the string to a cmd given by idx.
213 const std::string &toString() const { return commandInfo[cmd].str; }
214 int toInt() const { return (int)cmd; }
215
216 MemCmd(Command _cmd) : cmd(_cmd) { }
217 MemCmd(int _cmd) : cmd((Command)_cmd) { }
218 MemCmd() : cmd(InvalidCmd) { }
219
220 bool operator==(MemCmd c2) const { return (cmd == c2.cmd); }
221 bool operator!=(MemCmd c2) const { return (cmd != c2.cmd); }
222};
223
224/**
225 * A Packet is used to encapsulate a transfer between two objects in
226 * the memory system (e.g., the L1 and L2 cache). (In contrast, a
227 * single Request travels all the way from the requester to the
228 * ultimate destination and back, possibly being conveyed by several
229 * different Packets along the way.)
230 */
231class Packet : public Printable
232{
233 public:
234 typedef uint32_t FlagsType;
235 typedef ::Flags<FlagsType> Flags;
236
237 private:
238 static const FlagsType PUBLIC_FLAGS = 0x00000000;
239 static const FlagsType PRIVATE_FLAGS = 0x00007F0F;
240 static const FlagsType COPY_FLAGS = 0x0000000F;
241
242 static const FlagsType SHARED = 0x00000001;
243 // Special control flags
244 /// Special timing-mode atomic snoop for multi-level coherence.
245 static const FlagsType EXPRESS_SNOOP = 0x00000002;
246 /// Does supplier have exclusive copy?
247 /// Useful for multi-level coherence.
248 static const FlagsType SUPPLY_EXCLUSIVE = 0x00000004;
249 // Snoop response flags
250 static const FlagsType MEM_INHIBIT = 0x00000008;
251 /// Are the 'addr' and 'size' fields valid?
252 static const FlagsType VALID_ADDR = 0x00000100;
253 static const FlagsType VALID_SIZE = 0x00000200;
254 /// Is the data pointer set to a value that shouldn't be freed
255 /// when the packet is destroyed?
256 static const FlagsType STATIC_DATA = 0x00001000;
257 /// The data pointer points to a value that should be freed when
258 /// the packet is destroyed. The pointer is assumed to be pointing
259 /// to an array, and delete [] is consequently called
260 static const FlagsType DYNAMIC_DATA = 0x00002000;
261 /// suppress the error if this packet encounters a functional
262 /// access failure.
263 static const FlagsType SUPPRESS_FUNC_ERROR = 0x00008000;
264 // Signal prefetch squash through express snoop flag
265 static const FlagsType PREFETCH_SNOOP_SQUASH = 0x00010000;
266
267 Flags flags;
268
269 public:
270 typedef MemCmd::Command Command;
271
272 /// The command field of the packet.
273 MemCmd cmd;
274
275 /// A pointer to the original request.
276 const RequestPtr req;
277
278 private:
279 /**
280 * A pointer to the data being transfered. It can be differnt
281 * sizes at each level of the heirarchy so it belongs in the
282 * packet, not request. This may or may not be populated when a
283 * responder recieves the packet. If not populated it memory should
284 * be allocated.
285 */
286 PacketDataPtr data;
287
288 /// The address of the request. This address could be virtual or
289 /// physical, depending on the system configuration.
290 Addr addr;
291
292 /// True if the request targets the secure memory space.
293 bool _isSecure;
294
295 /// The size of the request or transfer.
296 unsigned size;
297
298 /**
299 * The original value of the command field. Only valid when the
300 * current command field is an error condition; in that case, the
301 * previous contents of the command field are copied here. This
302 * field is *not* set on non-error responses.
303 */
304 MemCmd origCmd;
305
306 /**
307 * These values specify the range of bytes found that satisfy a
308 * functional read.
307 * Track the bytes found that satisfy a functional read.
308 */
310 uint16_t bytesValidStart;
311 uint16_t bytesValidEnd;
309 std::vector<bool> bytesValid;
310
311 public:
312
313 /**
314 * The extra delay from seeing the packet until the header is
315 * transmitted. This delay is used to communicate the crossbar
316 * forwarding latency to the neighbouring object (e.g. a cache)
317 * that actually makes the packet wait. As the delay is relative,
318 * a 32-bit unsigned should be sufficient.
319 */
320 uint32_t headerDelay;
321
322 /**
323 * The extra pipelining delay from seeing the packet until the end of
324 * payload is transmitted by the component that provided it (if
325 * any). This includes the header delay. Similar to the header
326 * delay, this is used to make up for the fact that the
327 * crossbar does not make the packet wait. As the delay is
328 * relative, a 32-bit unsigned should be sufficient.
329 */
330 uint32_t payloadDelay;
331
332 /**
333 * A virtual base opaque structure used to hold state associated
334 * with the packet (e.g., an MSHR), specific to a MemObject that
335 * sees the packet. A pointer to this state is returned in the
336 * packet's response so that the MemObject in question can quickly
337 * look up the state needed to process it. A specific subclass
338 * would be derived from this to carry state specific to a
339 * particular sending device.
340 *
341 * As multiple MemObjects may add their SenderState throughout the
342 * memory system, the SenderStates create a stack, where a
343 * MemObject can add a new Senderstate, as long as the
344 * predecessing SenderState is restored when the response comes
345 * back. For this reason, the predecessor should always be
346 * populated with the current SenderState of a packet before
347 * modifying the senderState field in the request packet.
348 */
349 struct SenderState
350 {
351 SenderState* predecessor;
352 SenderState() : predecessor(NULL) {}
353 virtual ~SenderState() {}
354 };
355
356 /**
357 * Object used to maintain state of a PrintReq. The senderState
358 * field of a PrintReq should always be of this type.
359 */
360 class PrintReqState : public SenderState
361 {
362 private:
363 /**
364 * An entry in the label stack.
365 */
366 struct LabelStackEntry
367 {
368 const std::string label;
369 std::string *prefix;
370 bool labelPrinted;
371 LabelStackEntry(const std::string &_label, std::string *_prefix);
372 };
373
374 typedef std::list<LabelStackEntry> LabelStack;
375 LabelStack labelStack;
376
377 std::string *curPrefixPtr;
378
379 public:
380 std::ostream &os;
381 const int verbosity;
382
383 PrintReqState(std::ostream &os, int verbosity = 0);
384 ~PrintReqState();
385
386 /**
387 * Returns the current line prefix.
388 */
389 const std::string &curPrefix() { return *curPrefixPtr; }
390
391 /**
392 * Push a label onto the label stack, and prepend the given
393 * prefix string onto the current prefix. Labels will only be
394 * printed if an object within the label's scope is printed.
395 */
396 void pushLabel(const std::string &lbl,
397 const std::string &prefix = " ");
398
399 /**
400 * Pop a label off the label stack.
401 */
402 void popLabel();
403
404 /**
405 * Print all of the pending unprinted labels on the
406 * stack. Called by printObj(), so normally not called by
407 * users unless bypassing printObj().
408 */
409 void printLabels();
410
411 /**
412 * Print a Printable object to os, because it matched the
413 * address on a PrintReq.
414 */
415 void printObj(Printable *obj);
416 };
417
418 /**
419 * This packet's sender state. Devices should use dynamic_cast<>
420 * to cast to the state appropriate to the sender. The intent of
421 * this variable is to allow a device to attach extra information
422 * to a request. A response packet must return the sender state
423 * that was attached to the original request (even if a new packet
424 * is created).
425 */
426 SenderState *senderState;
427
428 /**
429 * Push a new sender state to the packet and make the current
430 * sender state the predecessor of the new one. This should be
431 * prefered over direct manipulation of the senderState member
432 * variable.
433 *
434 * @param sender_state SenderState to push at the top of the stack
435 */
436 void pushSenderState(SenderState *sender_state);
437
438 /**
439 * Pop the top of the state stack and return a pointer to it. This
440 * assumes the current sender state is not NULL. This should be
441 * preferred over direct manipulation of the senderState member
442 * variable.
443 *
444 * @return The current top of the stack
445 */
446 SenderState *popSenderState();
447
448 /**
449 * Go through the sender state stack and return the first instance
450 * that is of type T (as determined by a dynamic_cast). If there
451 * is no sender state of type T, NULL is returned.
452 *
453 * @return The topmost state of type T
454 */
455 template <typename T>
456 T * findNextSenderState() const
457 {
458 T *t = NULL;
459 SenderState* sender_state = senderState;
460 while (t == NULL && sender_state != NULL) {
461 t = dynamic_cast<T*>(sender_state);
462 sender_state = sender_state->predecessor;
463 }
464 return t;
465 }
466
467 /// Return the string name of the cmd field (for debugging and
468 /// tracing).
469 const std::string &cmdString() const { return cmd.toString(); }
470
471 /// Return the index of this command.
472 inline int cmdToIndex() const { return cmd.toInt(); }
473
474 bool isRead() const { return cmd.isRead(); }
475 bool isWrite() const { return cmd.isWrite(); }
476 bool isUpgrade() const { return cmd.isUpgrade(); }
477 bool isRequest() const { return cmd.isRequest(); }
478 bool isResponse() const { return cmd.isResponse(); }
479 bool needsExclusive() const { return cmd.needsExclusive(); }
480 bool needsResponse() const { return cmd.needsResponse(); }
481 bool isInvalidate() const { return cmd.isInvalidate(); }
482 bool isWriteInvalidate() const { return cmd.isWriteInvalidate(); }
483 bool hasData() const { return cmd.hasData(); }
484 bool isLLSC() const { return cmd.isLLSC(); }
485 bool isError() const { return cmd.isError(); }
486 bool isPrint() const { return cmd.isPrint(); }
487 bool isFlush() const { return cmd.isFlush(); }
488
489 // Snoop flags
490 void assertMemInhibit()
491 {
492 assert(isRequest());
493 assert(!flags.isSet(MEM_INHIBIT));
494 flags.set(MEM_INHIBIT);
495 }
496 bool memInhibitAsserted() const { return flags.isSet(MEM_INHIBIT); }
497 void assertShared() { flags.set(SHARED); }
498 bool sharedAsserted() const { return flags.isSet(SHARED); }
499
500 // Special control flags
501 void setExpressSnoop() { flags.set(EXPRESS_SNOOP); }
502 bool isExpressSnoop() const { return flags.isSet(EXPRESS_SNOOP); }
503 void setSupplyExclusive() { flags.set(SUPPLY_EXCLUSIVE); }
504 void clearSupplyExclusive() { flags.clear(SUPPLY_EXCLUSIVE); }
505 bool isSupplyExclusive() const { return flags.isSet(SUPPLY_EXCLUSIVE); }
506 void setSuppressFuncError() { flags.set(SUPPRESS_FUNC_ERROR); }
507 bool suppressFuncError() const { return flags.isSet(SUPPRESS_FUNC_ERROR); }
508 void setPrefetchSquashed() { flags.set(PREFETCH_SNOOP_SQUASH); }
509 bool prefetchSquashed() const { return flags.isSet(PREFETCH_SNOOP_SQUASH); }
510
511 // Network error conditions... encapsulate them as methods since
512 // their encoding keeps changing (from result field to command
513 // field, etc.)
514 void
515 setBadAddress()
516 {
517 assert(isResponse());
518 cmd = MemCmd::BadAddressError;
519 }
520
521 bool hadBadAddress() const { return cmd == MemCmd::BadAddressError; }
522 void copyError(Packet *pkt) { assert(pkt->isError()); cmd = pkt->cmd; }
523
524 Addr getAddr() const { assert(flags.isSet(VALID_ADDR)); return addr; }
525 /**
526 * Update the address of this packet mid-transaction. This is used
527 * by the address mapper to change an already set address to a new
528 * one based on the system configuration. It is intended to remap
529 * an existing address, so it asserts that the current address is
530 * valid.
531 */
532 void setAddr(Addr _addr) { assert(flags.isSet(VALID_ADDR)); addr = _addr; }
533
534 unsigned getSize() const { assert(flags.isSet(VALID_SIZE)); return size; }
535 Addr getOffset(int blkSize) const { return getAddr() & (Addr)(blkSize - 1); }
536
537 bool isSecure() const
538 {
539 assert(flags.isSet(VALID_ADDR));
540 return _isSecure;
541 }
542
543 /**
544 * It has been determined that the SC packet should successfully update
545 * memory. Therefore, convert this SC packet to a normal write.
546 */
547 void
548 convertScToWrite()
549 {
550 assert(isLLSC());
551 assert(isWrite());
552 cmd = MemCmd::WriteReq;
553 }
554
555 /**
556 * When ruby is in use, Ruby will monitor the cache line and thus M5
557 * phys memory should treat LL ops as normal reads.
558 */
559 void
560 convertLlToRead()
561 {
562 assert(isLLSC());
563 assert(isRead());
564 cmd = MemCmd::ReadReq;
565 }
566
567 /**
568 * Constructor. Note that a Request object must be constructed
569 * first, but the Requests's physical address and size fields need
570 * not be valid. The command must be supplied.
571 */
572 Packet(const RequestPtr _req, MemCmd _cmd)
573 : cmd(_cmd), req(_req), data(nullptr), addr(0), _isSecure(false),
576 size(0), bytesValidStart(0), bytesValidEnd(0),
577 headerDelay(0), payloadDelay(0),
574 size(0), headerDelay(0), payloadDelay(0),
575 senderState(NULL)
576 {
577 if (req->hasPaddr()) {
578 addr = req->getPaddr();
579 flags.set(VALID_ADDR);
580 _isSecure = req->isSecure();
581 }
582 if (req->hasSize()) {
583 size = req->getSize();
584 flags.set(VALID_SIZE);
585 }
586 }
587
588 /**
589 * Alternate constructor if you are trying to create a packet with
590 * a request that is for a whole block, not the address from the
591 * req. this allows for overriding the size/addr of the req.
592 */
593 Packet(const RequestPtr _req, MemCmd _cmd, int _blkSize)
594 : cmd(_cmd), req(_req), data(nullptr), addr(0), _isSecure(false),
598 bytesValidStart(0), bytesValidEnd(0),
595 headerDelay(0), payloadDelay(0),
596 senderState(NULL)
597 {
598 if (req->hasPaddr()) {
599 addr = req->getPaddr() & ~(_blkSize - 1);
600 flags.set(VALID_ADDR);
601 _isSecure = req->isSecure();
602 }
603 size = _blkSize;
604 flags.set(VALID_SIZE);
605 }
606
607 /**
608 * Alternate constructor for copying a packet. Copy all fields
609 * *except* if the original packet's data was dynamic, don't copy
610 * that, as we can't guarantee that the new packet's lifetime is
611 * less than that of the original packet. In this case the new
612 * packet should allocate its own data.
613 */
614 Packet(PacketPtr pkt, bool clear_flags, bool alloc_data)
615 : cmd(pkt->cmd), req(pkt->req),
616 data(nullptr),
617 addr(pkt->addr), _isSecure(pkt->_isSecure), size(pkt->size),
622 bytesValidStart(pkt->bytesValidStart),
623 bytesValidEnd(pkt->bytesValidEnd),
618 bytesValid(pkt->bytesValid),
619 headerDelay(pkt->headerDelay),
620 payloadDelay(pkt->payloadDelay),
621 senderState(pkt->senderState)
622 {
623 if (!clear_flags)
624 flags.set(pkt->flags & COPY_FLAGS);
625
626 flags.set(pkt->flags & (VALID_ADDR|VALID_SIZE));
627
628 // should we allocate space for data, or not, the express
629 // snoops do not need to carry any data as they only serve to
630 // co-ordinate state changes
631 if (alloc_data) {
632 // even if asked to allocate data, if the original packet
633 // holds static data, then the sender will not be doing
634 // any memcpy on receiving the response, thus we simply
635 // carry the pointer forward
636 if (pkt->flags.isSet(STATIC_DATA)) {
637 data = pkt->data;
638 flags.set(STATIC_DATA);
639 } else {
640 allocate();
641 }
642 }
643 }
644
645 /**
646 * Change the packet type based on request type.
647 */
648 void
649 refineCommand()
650 {
651 if (cmd == MemCmd::ReadReq) {
652 if (req->isLLSC()) {
653 cmd = MemCmd::LoadLockedReq;
654 } else if (req->isPrefetch()) {
655 cmd = MemCmd::SoftPFReq;
656 }
657 } else if (cmd == MemCmd::WriteReq) {
658 if (req->isLLSC()) {
659 cmd = MemCmd::StoreCondReq;
660 } else if (req->isSwap()) {
661 cmd = MemCmd::SwapReq;
662 }
663 }
664 }
665
666 /**
667 * Constructor-like methods that return Packets based on Request objects.
668 * Will call refineCommand() to fine-tune the Packet type if it's not a
669 * vanilla read or write.
670 */
671 static PacketPtr
672 createRead(const RequestPtr req)
673 {
674 PacketPtr pkt = new Packet(req, MemCmd::ReadReq);
675 pkt->refineCommand();
676 return pkt;
677 }
678
679 static PacketPtr
680 createWrite(const RequestPtr req)
681 {
682 PacketPtr pkt = new Packet(req, MemCmd::WriteReq);
683 pkt->refineCommand();
684 return pkt;
685 }
686
687 /**
688 * clean up packet variables
689 */
690 ~Packet()
691 {
692 // If this is a request packet for which there's no response,
693 // delete the request object here, since the requester will
694 // never get the chance.
695 if (req && isRequest() && !needsResponse())
696 delete req;
697 deleteData();
698 }
699
700 /**
701 * Take a request packet and modify it in place to be suitable for
702 * returning as a response to that request.
703 */
704 void
705 makeResponse()
706 {
707 assert(needsResponse());
708 assert(isRequest());
709 origCmd = cmd;
710 cmd = cmd.responseCommand();
711
712 // responses are never express, even if the snoop that
713 // triggered them was
714 flags.clear(EXPRESS_SNOOP);
715 }
716
717 void
718 makeAtomicResponse()
719 {
720 makeResponse();
721 }
722
723 void
724 makeTimingResponse()
725 {
726 makeResponse();
727 }
728
729 void
730 setFunctionalResponseStatus(bool success)
731 {
732 if (!success) {
733 if (isWrite()) {
734 cmd = MemCmd::FunctionalWriteError;
735 } else {
736 cmd = MemCmd::FunctionalReadError;
737 }
738 }
739 }
740
741 void
742 setSize(unsigned size)
743 {
744 assert(!flags.isSet(VALID_SIZE));
745
746 this->size = size;
747 flags.set(VALID_SIZE);
748 }
749
750
751 /**
752 * Set the data pointer to the following value that should not be
753 * freed. Static data allows us to do a single memcpy even if
754 * multiple packets are required to get from source to destination
755 * and back. In essence the pointer is set calling dataStatic on
756 * the original packet, and whenever this packet is copied and
757 * forwarded the same pointer is passed on. When a packet
758 * eventually reaches the destination holding the data, it is
759 * copied once into the location originally set. On the way back
760 * to the source, no copies are necessary.
761 */
762 template <typename T>
763 void
764 dataStatic(T *p)
765 {
766 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
767 data = (PacketDataPtr)p;
768 flags.set(STATIC_DATA);
769 }
770
771 /**
772 * Set the data pointer to the following value that should not be
773 * freed. This version of the function allows the pointer passed
774 * to us to be const. To avoid issues down the line we cast the
775 * constness away, the alternative would be to keep both a const
776 * and non-const data pointer and cleverly choose between
777 * them. Note that this is only allowed for static data.
778 */
779 template <typename T>
780 void
781 dataStaticConst(const T *p)
782 {
783 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
784 data = const_cast<PacketDataPtr>(p);
785 flags.set(STATIC_DATA);
786 }
787
788 /**
789 * Set the data pointer to a value that should have delete []
790 * called on it. Dynamic data is local to this packet, and as the
791 * packet travels from source to destination, forwarded packets
792 * will allocate their own data. When a packet reaches the final
793 * destination it will populate the dynamic data of that specific
794 * packet, and on the way back towards the source, memcpy will be
795 * invoked in every step where a new packet was created e.g. in
796 * the caches. Ultimately when the response reaches the source a
797 * final memcpy is needed to extract the data from the packet
798 * before it is deallocated.
799 */
800 template <typename T>
801 void
802 dataDynamic(T *p)
803 {
804 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
805 data = (PacketDataPtr)p;
806 flags.set(DYNAMIC_DATA);
807 }
808
809 /**
810 * get a pointer to the data ptr.
811 */
812 template <typename T>
813 T*
814 getPtr()
815 {
816 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
817 return (T*)data;
818 }
819
820 template <typename T>
821 const T*
822 getConstPtr() const
823 {
824 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
825 return (const T*)data;
826 }
827
828 /**
829 * return the value of what is pointed to in the packet.
830 */
831 template <typename T>
832 T get() const;
833
834 /**
835 * set the value in the data pointer to v.
836 */
837 template <typename T>
838 void set(T v);
839
840 /**
841 * Copy data into the packet from the provided pointer.
842 */
843 void
844 setData(const uint8_t *p)
845 {
846 // we should never be copying data onto itself, which means we
847 // must idenfity packets with static data, as they carry the
848 // same pointer from source to destination and back
849 assert(p != getPtr<uint8_t>() || flags.isSet(STATIC_DATA));
850
851 if (p != getPtr<uint8_t>())
852 // for packet with allocated dynamic data, we copy data from
853 // one to the other, e.g. a forwarded response to a response
854 std::memcpy(getPtr<uint8_t>(), p, getSize());
855 }
856
857 /**
858 * Copy data into the packet from the provided block pointer,
859 * which is aligned to the given block size.
860 */
861 void
862 setDataFromBlock(const uint8_t *blk_data, int blkSize)
863 {
864 setData(blk_data + getOffset(blkSize));
865 }
866
867 /**
868 * Copy data from the packet to the provided block pointer, which
869 * is aligned to the given block size.
870 */
871 void
872 writeData(uint8_t *p) const
873 {
874 std::memcpy(p, getConstPtr<uint8_t>(), getSize());
875 }
876
877 /**
878 * Copy data from the packet to the memory at the provided pointer.
879 */
880 void
881 writeDataToBlock(uint8_t *blk_data, int blkSize) const
882 {
883 writeData(blk_data + getOffset(blkSize));
884 }
885
886 /**
887 * delete the data pointed to in the data pointer. Ok to call to
888 * matter how data was allocted.
889 */
890 void
891 deleteData()
892 {
893 if (flags.isSet(DYNAMIC_DATA))
894 delete [] data;
895
896 flags.clear(STATIC_DATA|DYNAMIC_DATA);
897 data = NULL;
898 }
899
900 /** Allocate memory for the packet. */
901 void
902 allocate()
903 {
904 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
905 flags.set(DYNAMIC_DATA);
906 data = new uint8_t[getSize()];
907 }
908
909 /**
910 * Check a functional request against a memory value stored in
911 * another packet (i.e. an in-transit request or
912 * response). Returns true if the current packet is a read, and
913 * the other packet provides the data, which is then copied to the
914 * current packet. If the current packet is a write, and the other
915 * packet intersects this one, then we update the data
916 * accordingly.
917 */
918 bool
919 checkFunctional(PacketPtr other)
920 {
921 // all packets that are carrying a payload should have a valid
922 // data pointer
923 return checkFunctional(other, other->getAddr(), other->isSecure(),
924 other->getSize(),
925 other->hasData() ?
926 other->getPtr<uint8_t>() : NULL);
927 }
928
929 /**
930 * Check a functional request against a memory value represented
931 * by a base/size pair and an associated data array. If the
932 * current packet is a read, it may be satisfied by the memory
933 * value. If the current packet is a write, it may update the
934 * memory value.
935 */
936 bool
937 checkFunctional(Printable *obj, Addr base, bool is_secure, int size,
938 uint8_t *_data);
939
940 /**
941 * Push label for PrintReq (safe to call unconditionally).
942 */
943 void
944 pushLabel(const std::string &lbl)
945 {
946 if (isPrint())
947 safe_cast<PrintReqState*>(senderState)->pushLabel(lbl);
948 }
949
950 /**
951 * Pop label for PrintReq (safe to call unconditionally).
952 */
953 void
954 popLabel()
955 {
956 if (isPrint())
957 safe_cast<PrintReqState*>(senderState)->popLabel();
958 }
959
960 void print(std::ostream &o, int verbosity = 0,
961 const std::string &prefix = "") const;
962
963 /**
964 * A no-args wrapper of print(std::ostream...)
965 * meant to be invoked from DPRINTFs
966 * avoiding string overheads in fast mode
967 * @return string with the request's type and start<->end addresses
968 */
969 std::string print() const;
970};
971
972#endif //__MEM_PACKET_HH