1/*
2 * Copyright (c) 2012-2018 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 * Nikos Nikoleris
46 */
47
48/**
49 * @file
50 * Declaration of the Packet class.
51 */
52
53#ifndef __MEM_PACKET_HH__
54#define __MEM_PACKET_HH__
55
56#include <bitset>
57#include <cassert>
58#include <list>
59
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"
68
69class Packet;
70typedef Packet *PacketPtr;
71typedef uint8_t* PacketDataPtr;
72typedef std::list<PacketPtr> PacketList;
73typedef uint64_t PacketId;
74
75class MemCmd
76{
77 friend class Packet;
78
79 public:
80 /**
81 * List of all commands associated with a packet.
82 */
83 enum Command
84 {
85 InvalidCmd,
86 ReadReq,
87 ReadResp,
88 ReadRespWithInvalidate,
89 WriteReq,
90 WriteResp,
91 WritebackDirty,
92 WritebackClean,
93 WriteClean, // writes dirty data below without evicting
94 CleanEvict,
95 SoftPFReq,
96 HardPFReq,
97 SoftPFResp,
98 HardPFResp,
99 WriteLineReq,
100 UpgradeReq,
101 SCUpgradeReq, // Special "weak" upgrade for StoreCond
102 UpgradeResp,
103 SCUpgradeFailReq, // Failed SCUpgradeReq in MSHR (never sent)
104 UpgradeFailResp, // Valid for SCUpgradeReq only
105 ReadExReq,
106 ReadExResp,
107 ReadCleanReq,
108 ReadSharedReq,
109 LoadLockedReq,
110 StoreCondReq,
111 StoreCondFailReq, // Failed StoreCondReq in MSHR (never sent)
112 StoreCondResp,
113 SwapReq,
114 SwapResp,
115 MessageReq,
116 MessageResp,
117 MemFenceReq,
118 MemFenceResp,
119 CleanSharedReq,
120 CleanSharedResp,
121 CleanInvalidReq,
122 CleanInvalidResp,
123 // Error responses
124 // @TODO these should be classified as responses rather than
125 // requests; coding them as requests initially for backwards
126 // compatibility
127 InvalidDestError, // packet dest field invalid
128 BadAddressError, // memory address invalid
129 FunctionalReadError, // unable to fulfill functional read
130 FunctionalWriteError, // unable to fulfill functional write
131 // Fake simulator-only commands
132 PrintReq, // Print state matching address
133 FlushReq, //request for a cache flush
134 InvalidateReq, // request for address to be invalidated
135 InvalidateResp,
136 NUM_MEM_CMDS
137 };
138
139 private:
140 /**
141 * List of command attributes.
142 */
143 enum Attribute
144 {
145 IsRead, //!< Data flows from responder to requester
146 IsWrite, //!< Data flows from requester to responder
147 IsUpgrade,
148 IsInvalidate,
149 IsClean, //!< Cleans any existing dirty blocks
150 NeedsWritable, //!< Requires writable copy to complete in-cache
151 IsRequest, //!< Issued by requester
152 IsResponse, //!< Issue by responder
153 NeedsResponse, //!< Requester needs response from target
154 IsEviction,
155 IsSWPrefetch,
156 IsHWPrefetch,
157 IsLlsc, //!< Alpha/MIPS LL or SC access
158 HasData, //!< There is an associated payload
159 IsError, //!< Error response
160 IsPrint, //!< Print state matching address (for debugging)
161 IsFlush, //!< Flush the address from caches
162 FromCache, //!< Request originated from a caching agent
163 NUM_COMMAND_ATTRIBUTES
164 };
165
166 /**
167 * Structure that defines attributes and other data associated
168 * with a Command.
169 */
170 struct CommandInfo
171 {
172 /// Set of attribute flags.
173 const std::bitset<NUM_COMMAND_ATTRIBUTES> attributes;
174 /// Corresponding response for requests; InvalidCmd if no
175 /// response is applicable.
176 const Command response;
177 /// String representation (for printing)
178 const std::string str;
179 };
180
181 /// Array to map Command enum to associated info.
182 static const CommandInfo commandInfo[];
183
184 private:
185
186 Command cmd;
187
188 bool
189 testCmdAttrib(MemCmd::Attribute attrib) const
190 {
191 return commandInfo[cmd].attributes[attrib] != 0;
192 }
193
194 public:
195
196 bool isRead() const { return testCmdAttrib(IsRead); }
197 bool isWrite() const { return testCmdAttrib(IsWrite); }
198 bool isUpgrade() const { return testCmdAttrib(IsUpgrade); }
199 bool isRequest() const { return testCmdAttrib(IsRequest); }
200 bool isResponse() const { return testCmdAttrib(IsResponse); }
201 bool needsWritable() const { return testCmdAttrib(NeedsWritable); }
202 bool needsResponse() const { return testCmdAttrib(NeedsResponse); }
203 bool isInvalidate() const { return testCmdAttrib(IsInvalidate); }
204 bool isEviction() const { return testCmdAttrib(IsEviction); }
205 bool isClean() const { return testCmdAttrib(IsClean); }
206 bool fromCache() const { return testCmdAttrib(FromCache); }
207
208 /**
209 * A writeback is an eviction that carries data.
210 */
211 bool isWriteback() const { return testCmdAttrib(IsEviction) &&
212 testCmdAttrib(HasData); }
213
214 /**
215 * Check if this particular packet type carries payload data. Note
216 * that this does not reflect if the data pointer of the packet is
217 * valid or not.
218 */
219 bool hasData() const { return testCmdAttrib(HasData); }
220 bool isLLSC() const { return testCmdAttrib(IsLlsc); }
221 bool isSWPrefetch() const { return testCmdAttrib(IsSWPrefetch); }
222 bool isHWPrefetch() const { return testCmdAttrib(IsHWPrefetch); }
223 bool isPrefetch() const { return testCmdAttrib(IsSWPrefetch) ||
224 testCmdAttrib(IsHWPrefetch); }
225 bool isError() const { return testCmdAttrib(IsError); }
226 bool isPrint() const { return testCmdAttrib(IsPrint); }
227 bool isFlush() const { return testCmdAttrib(IsFlush); }
228
229 Command
230 responseCommand() const
231 {
232 return commandInfo[cmd].response;
233 }
234
235 /// Return the string to a cmd given by idx.
236 const std::string &toString() const { return commandInfo[cmd].str; }
237 int toInt() const { return (int)cmd; }
238
239 MemCmd(Command _cmd) : cmd(_cmd) { }
240 MemCmd(int _cmd) : cmd((Command)_cmd) { }
241 MemCmd() : cmd(InvalidCmd) { }
242
243 bool operator==(MemCmd c2) const { return (cmd == c2.cmd); }
244 bool operator!=(MemCmd c2) const { return (cmd != c2.cmd); }
245};
246
247/**
248 * A Packet is used to encapsulate a transfer between two objects in
249 * the memory system (e.g., the L1 and L2 cache). (In contrast, a
250 * single Request travels all the way from the requester to the
251 * ultimate destination and back, possibly being conveyed by several
252 * different Packets along the way.)
253 */
254class Packet : public Printable
255{
256 public:
257 typedef uint32_t FlagsType;
258 typedef ::Flags<FlagsType> Flags;
259
260 private:
261
262 enum : FlagsType {
263 // Flags to transfer across when copying a packet
264 COPY_FLAGS = 0x0000003F,
265
266 // Does this packet have sharers (which means it should not be
267 // considered writable) or not. See setHasSharers below.
268 HAS_SHARERS = 0x00000001,
269
270 // Special control flags
271 /// Special timing-mode atomic snoop for multi-level coherence.
272 EXPRESS_SNOOP = 0x00000002,
273
274 /// Allow a responding cache to inform the cache hierarchy
275 /// that it had a writable copy before responding. See
276 /// setResponderHadWritable below.
277 RESPONDER_HAD_WRITABLE = 0x00000004,
278
279 // Snoop co-ordination flag to indicate that a cache is
280 // responding to a snoop. See setCacheResponding below.
281 CACHE_RESPONDING = 0x00000008,
282
283 // The writeback/writeclean should be propagated further
284 // downstream by the receiver
285 WRITE_THROUGH = 0x00000010,
286
287 // Response co-ordination flag for cache maintenance
288 // operations
289 SATISFIED = 0x00000020,
290
291 /// Are the 'addr' and 'size' fields valid?
292 VALID_ADDR = 0x00000100,
293 VALID_SIZE = 0x00000200,
294
295 /// Is the data pointer set to a value that shouldn't be freed
296 /// when the packet is destroyed?
297 STATIC_DATA = 0x00001000,
298 /// The data pointer points to a value that should be freed when
299 /// the packet is destroyed. The pointer is assumed to be pointing
300 /// to an array, and delete [] is consequently called
301 DYNAMIC_DATA = 0x00002000,
302
303 /// suppress the error if this packet encounters a functional
304 /// access failure.
305 SUPPRESS_FUNC_ERROR = 0x00008000,
306
307 // Signal block present to squash prefetch and cache evict packets
308 // through express snoop flag
309 BLOCK_CACHED = 0x00010000
310 };
311
312 Flags flags;
313
314 public:
315 typedef MemCmd::Command Command;
316
317 /// The command field of the packet.
318 MemCmd cmd;
319
320 const PacketId id;
321
322 /// A pointer to the original request.
323 RequestPtr req;
324
325 private:
326 /**
327 * A pointer to the data being transferred. It can be different
328 * sizes at each level of the hierarchy so it belongs to the
329 * packet, not request. This may or may not be populated when a
330 * responder receives the packet. If not populated memory should
331 * be allocated.
332 */
333 PacketDataPtr data;
334
335 /// The address of the request. This address could be virtual or
336 /// physical, depending on the system configuration.
337 Addr addr;
338
339 /// True if the request targets the secure memory space.
340 bool _isSecure;
341
342 /// The size of the request or transfer.
343 unsigned size;
344
345 /**
346 * Track the bytes found that satisfy a functional read.
347 */
348 std::vector<bool> bytesValid;
349
350 public:
351
352 /**
353 * The extra delay from seeing the packet until the header is
354 * transmitted. This delay is used to communicate the crossbar
355 * forwarding latency to the neighbouring object (e.g. a cache)
356 * that actually makes the packet wait. As the delay is relative,
357 * a 32-bit unsigned should be sufficient.
358 */
359 uint32_t headerDelay;
360
361 /**
362 * Keep track of the extra delay incurred by snooping upwards
363 * before sending a request down the memory system. This is used
364 * by the coherent crossbar to account for the additional request
365 * delay.
366 */
367 uint32_t snoopDelay;
368
369 /**
370 * The extra pipelining delay from seeing the packet until the end of
371 * payload is transmitted by the component that provided it (if
372 * any). This includes the header delay. Similar to the header
373 * delay, this is used to make up for the fact that the
374 * crossbar does not make the packet wait. As the delay is
375 * relative, a 32-bit unsigned should be sufficient.
376 */
377 uint32_t payloadDelay;
378
379 /**
380 * A virtual base opaque structure used to hold state associated
381 * with the packet (e.g., an MSHR), specific to a MemObject that
382 * sees the packet. A pointer to this state is returned in the
383 * packet's response so that the MemObject in question can quickly
384 * look up the state needed to process it. A specific subclass
385 * would be derived from this to carry state specific to a
386 * particular sending device.
387 *
388 * As multiple MemObjects may add their SenderState throughout the
389 * memory system, the SenderStates create a stack, where a
390 * MemObject can add a new Senderstate, as long as the
391 * predecessing SenderState is restored when the response comes
392 * back. For this reason, the predecessor should always be
393 * populated with the current SenderState of a packet before
394 * modifying the senderState field in the request packet.
395 */
396 struct SenderState
397 {
398 SenderState* predecessor;
399 SenderState() : predecessor(NULL) {}
400 virtual ~SenderState() {}
401 };
402
403 /**
404 * Object used to maintain state of a PrintReq. The senderState
405 * field of a PrintReq should always be of this type.
406 */
407 class PrintReqState : public SenderState
408 {
409 private:
410 /**
411 * An entry in the label stack.
412 */
413 struct LabelStackEntry
414 {
415 const std::string label;
416 std::string *prefix;
417 bool labelPrinted;
418 LabelStackEntry(const std::string &_label, std::string *_prefix);
419 };
420
421 typedef std::list<LabelStackEntry> LabelStack;
422 LabelStack labelStack;
423
424 std::string *curPrefixPtr;
425
426 public:
427 std::ostream &os;
428 const int verbosity;
429
430 PrintReqState(std::ostream &os, int verbosity = 0);
431 ~PrintReqState();
432
433 /**
434 * Returns the current line prefix.
435 */
436 const std::string &curPrefix() { return *curPrefixPtr; }
437
438 /**
439 * Push a label onto the label stack, and prepend the given
440 * prefix string onto the current prefix. Labels will only be
441 * printed if an object within the label's scope is printed.
442 */
443 void pushLabel(const std::string &lbl,
444 const std::string &prefix = " ");
445
446 /**
447 * Pop a label off the label stack.
448 */
449 void popLabel();
450
451 /**
452 * Print all of the pending unprinted labels on the
453 * stack. Called by printObj(), so normally not called by
454 * users unless bypassing printObj().
455 */
456 void printLabels();
457
458 /**
459 * Print a Printable object to os, because it matched the
460 * address on a PrintReq.
461 */
462 void printObj(Printable *obj);
463 };
464
465 /**
466 * This packet's sender state. Devices should use dynamic_cast<>
467 * to cast to the state appropriate to the sender. The intent of
468 * this variable is to allow a device to attach extra information
469 * to a request. A response packet must return the sender state
470 * that was attached to the original request (even if a new packet
471 * is created).
472 */
473 SenderState *senderState;
474
475 /**
476 * Push a new sender state to the packet and make the current
477 * sender state the predecessor of the new one. This should be
478 * prefered over direct manipulation of the senderState member
479 * variable.
480 *
481 * @param sender_state SenderState to push at the top of the stack
482 */
483 void pushSenderState(SenderState *sender_state);
484
485 /**
486 * Pop the top of the state stack and return a pointer to it. This
487 * assumes the current sender state is not NULL. This should be
488 * preferred over direct manipulation of the senderState member
489 * variable.
490 *
491 * @return The current top of the stack
492 */
493 SenderState *popSenderState();
494
495 /**
496 * Go through the sender state stack and return the first instance
497 * that is of type T (as determined by a dynamic_cast). If there
498 * is no sender state of type T, NULL is returned.
499 *
500 * @return The topmost state of type T
501 */
502 template <typename T>
503 T * findNextSenderState() const
504 {
505 T *t = NULL;
506 SenderState* sender_state = senderState;
507 while (t == NULL && sender_state != NULL) {
508 t = dynamic_cast<T*>(sender_state);
509 sender_state = sender_state->predecessor;
510 }
511 return t;
512 }
513
514 /// Return the string name of the cmd field (for debugging and
515 /// tracing).
516 const std::string &cmdString() const { return cmd.toString(); }
517
518 /// Return the index of this command.
519 inline int cmdToIndex() const { return cmd.toInt(); }
520
521 bool isRead() const { return cmd.isRead(); }
522 bool isWrite() const { return cmd.isWrite(); }
523 bool isUpgrade() const { return cmd.isUpgrade(); }
524 bool isRequest() const { return cmd.isRequest(); }
525 bool isResponse() const { return cmd.isResponse(); }
526 bool needsWritable() const
527 {
528 // we should never check if a response needsWritable, the
529 // request has this flag, and for a response we should rather
530 // look at the hasSharers flag (if not set, the response is to
531 // be considered writable)
532 assert(isRequest());
533 return cmd.needsWritable();
534 }
535 bool needsResponse() const { return cmd.needsResponse(); }
536 bool isInvalidate() const { return cmd.isInvalidate(); }
537 bool isEviction() const { return cmd.isEviction(); }
538 bool isClean() const { return cmd.isClean(); }
539 bool fromCache() const { return cmd.fromCache(); }
540 bool isWriteback() const { return cmd.isWriteback(); }
541 bool hasData() const { return cmd.hasData(); }
542 bool hasRespData() const
543 {
544 MemCmd resp_cmd = cmd.responseCommand();
545 return resp_cmd.hasData();
546 }
547 bool isLLSC() const { return cmd.isLLSC(); }
548 bool isError() const { return cmd.isError(); }
549 bool isPrint() const { return cmd.isPrint(); }
550 bool isFlush() const { return cmd.isFlush(); }
551
552 //@{
553 /// Snoop flags
554 /**
555 * Set the cacheResponding flag. This is used by the caches to
556 * signal another cache that they are responding to a request. A
557 * cache will only respond to snoops if it has the line in either
558 * Modified or Owned state. Note that on snoop hits we always pass
559 * the line as Modified and never Owned. In the case of an Owned
560 * line we proceed to invalidate all other copies.
561 *
562 * On a cache fill (see Cache::handleFill), we check hasSharers
563 * first, ignoring the cacheResponding flag if hasSharers is set.
564 * A line is consequently allocated as:
565 *
566 * hasSharers cacheResponding state
567 * true false Shared
568 * true true Shared
569 * false false Exclusive
570 * false true Modified
571 */
572 void setCacheResponding()
573 {
574 assert(isRequest());
575 assert(!flags.isSet(CACHE_RESPONDING));
576 flags.set(CACHE_RESPONDING);
577 }
578 bool cacheResponding() const { return flags.isSet(CACHE_RESPONDING); }
579 /**
580 * On fills, the hasSharers flag is used by the caches in
581 * combination with the cacheResponding flag, as clarified
582 * above. If the hasSharers flag is not set, the packet is passing
583 * writable. Thus, a response from a memory passes the line as
584 * writable by default.
585 *
586 * The hasSharers flag is also used by upstream caches to inform a
587 * downstream cache that they have the block (by calling
588 * setHasSharers on snoop request packets that hit in upstream
589 * cachs tags or MSHRs). If the snoop packet has sharers, a
590 * downstream cache is prevented from passing a dirty line upwards
591 * if it was not explicitly asked for a writable copy. See
592 * Cache::satisfyCpuSideRequest.
593 *
594 * The hasSharers flag is also used on writebacks, in
595 * combination with the WritbackClean or WritebackDirty commands,
596 * to allocate the block downstream either as:
597 *
598 * command hasSharers state
599 * WritebackDirty false Modified
600 * WritebackDirty true Owned
601 * WritebackClean false Exclusive
602 * WritebackClean true Shared
603 */
604 void setHasSharers() { flags.set(HAS_SHARERS); }
605 bool hasSharers() const { return flags.isSet(HAS_SHARERS); }
606 //@}
607
608 /**
609 * The express snoop flag is used for two purposes. Firstly, it is
610 * used to bypass flow control for normal (non-snoop) requests
611 * going downstream in the memory system. In cases where a cache
612 * is responding to a snoop from another cache (it had a dirty
613 * line), but the line is not writable (and there are possibly
614 * other copies), the express snoop flag is set by the downstream
615 * cache to invalidate all other copies in zero time. Secondly,
616 * the express snoop flag is also set to be able to distinguish
617 * snoop packets that came from a downstream cache, rather than
618 * snoop packets from neighbouring caches.
619 */
620 void setExpressSnoop() { flags.set(EXPRESS_SNOOP); }
621 bool isExpressSnoop() const { return flags.isSet(EXPRESS_SNOOP); }
622
623 /**
624 * On responding to a snoop request (which only happens for
625 * Modified or Owned lines), make sure that we can transform an
626 * Owned response to a Modified one. If this flag is not set, the
627 * responding cache had the line in the Owned state, and there are
628 * possibly other Shared copies in the memory system. A downstream
629 * cache helps in orchestrating the invalidation of these copies
630 * by sending out the appropriate express snoops.
631 */
632 void setResponderHadWritable()
633 {
634 assert(cacheResponding());
635 assert(!responderHadWritable());
636 flags.set(RESPONDER_HAD_WRITABLE);
637 }
638 bool responderHadWritable() const
639 { return flags.isSet(RESPONDER_HAD_WRITABLE); }
640
641 /**
642 * A writeback/writeclean cmd gets propagated further downstream
643 * by the receiver when the flag is set.
644 */
645 void setWriteThrough()
646 {
647 assert(cmd.isWrite() &&
648 (cmd.isEviction() || cmd == MemCmd::WriteClean));
649 flags.set(WRITE_THROUGH);
650 }
651 void clearWriteThrough() { flags.clear(WRITE_THROUGH); }
652 bool writeThrough() const { return flags.isSet(WRITE_THROUGH); }
653
654 /**
655 * Set when a request hits in a cache and the cache is not going
656 * to respond. This is used by the crossbar to coordinate
657 * responses for cache maintenance operations.
658 */
659 void setSatisfied()
660 {
661 assert(cmd.isClean());
662 assert(!flags.isSet(SATISFIED));
663 flags.set(SATISFIED);
664 }
665 bool satisfied() const { return flags.isSet(SATISFIED); }
666
667 void setSuppressFuncError() { flags.set(SUPPRESS_FUNC_ERROR); }
668 bool suppressFuncError() const { return flags.isSet(SUPPRESS_FUNC_ERROR); }
669 void setBlockCached() { flags.set(BLOCK_CACHED); }
670 bool isBlockCached() const { return flags.isSet(BLOCK_CACHED); }
671 void clearBlockCached() { flags.clear(BLOCK_CACHED); }
672
673 // Network error conditions... encapsulate them as methods since
674 // their encoding keeps changing (from result field to command
675 // field, etc.)
676 void
677 setBadAddress()
678 {
679 assert(isResponse());
680 cmd = MemCmd::BadAddressError;
681 }
682
683 void copyError(Packet *pkt) { assert(pkt->isError()); cmd = pkt->cmd; }
684
685 Addr getAddr() const { assert(flags.isSet(VALID_ADDR)); return addr; }
686 /**
687 * Update the address of this packet mid-transaction. This is used
688 * by the address mapper to change an already set address to a new
689 * one based on the system configuration. It is intended to remap
690 * an existing address, so it asserts that the current address is
691 * valid.
692 */
693 void setAddr(Addr _addr) { assert(flags.isSet(VALID_ADDR)); addr = _addr; }
694
695 unsigned getSize() const { assert(flags.isSet(VALID_SIZE)); return size; }
696
697 Addr getOffset(unsigned int blk_size) const
698 {
699 return getAddr() & Addr(blk_size - 1);
700 }
701
702 Addr getBlockAddr(unsigned int blk_size) const
703 {
704 return getAddr() & ~(Addr(blk_size - 1));
705 }
706
707 bool isSecure() const
708 {
709 assert(flags.isSet(VALID_ADDR));
710 return _isSecure;
711 }
712
713 /**
714 * Accessor function to atomic op.
715 */
716 AtomicOpFunctor *getAtomicOp() const { return req->getAtomicOpFunctor(); }
717 bool isAtomicOp() const { return req->isAtomic(); }
718
719 /**
720 * It has been determined that the SC packet should successfully update
721 * memory. Therefore, convert this SC packet to a normal write.
722 */
723 void
724 convertScToWrite()
725 {
726 assert(isLLSC());
727 assert(isWrite());
728 cmd = MemCmd::WriteReq;
729 }
730
731 /**
732 * When ruby is in use, Ruby will monitor the cache line and the
733 * phys memory should treat LL ops as normal reads.
734 */
735 void
736 convertLlToRead()
737 {
738 assert(isLLSC());
739 assert(isRead());
740 cmd = MemCmd::ReadReq;
741 }
742
743 /**
744 * Constructor. Note that a Request object must be constructed
745 * first, but the Requests's physical address and size fields need
746 * not be valid. The command must be supplied.
747 */
748 Packet(const RequestPtr &_req, MemCmd _cmd)
749 : cmd(_cmd), id((PacketId)_req.get()), req(_req), data(nullptr),
750 addr(0), _isSecure(false), size(0), headerDelay(0), snoopDelay(0),
751 payloadDelay(0), senderState(NULL)
752 {
753 if (req->hasPaddr()) {
754 addr = req->getPaddr();
755 flags.set(VALID_ADDR);
756 _isSecure = req->isSecure();
757 }
758 if (req->hasSize()) {
759 size = req->getSize();
760 flags.set(VALID_SIZE);
761 }
762 }
763
764 /**
765 * Alternate constructor if you are trying to create a packet with
766 * a request that is for a whole block, not the address from the
767 * req. this allows for overriding the size/addr of the req.
768 */
769 Packet(const RequestPtr &_req, MemCmd _cmd, int _blkSize, PacketId _id = 0)
770 : cmd(_cmd), id(_id ? _id : (PacketId)_req.get()), req(_req),
771 data(nullptr), addr(0), _isSecure(false), headerDelay(0),
772 snoopDelay(0), payloadDelay(0), senderState(NULL)
773 {
774 if (req->hasPaddr()) {
775 addr = req->getPaddr() & ~(_blkSize - 1);
776 flags.set(VALID_ADDR);
777 _isSecure = req->isSecure();
778 }
779 size = _blkSize;
780 flags.set(VALID_SIZE);
781 }
782
783 /**
784 * Alternate constructor for copying a packet. Copy all fields
785 * *except* if the original packet's data was dynamic, don't copy
786 * that, as we can't guarantee that the new packet's lifetime is
787 * less than that of the original packet. In this case the new
788 * packet should allocate its own data.
789 */
790 Packet(const PacketPtr pkt, bool clear_flags, bool alloc_data)
791 : cmd(pkt->cmd), id(pkt->id), req(pkt->req),
792 data(nullptr),
793 addr(pkt->addr), _isSecure(pkt->_isSecure), size(pkt->size),
794 bytesValid(pkt->bytesValid),
795 headerDelay(pkt->headerDelay),
796 snoopDelay(0),
797 payloadDelay(pkt->payloadDelay),
798 senderState(pkt->senderState)
799 {
800 if (!clear_flags)
801 flags.set(pkt->flags & COPY_FLAGS);
802
803 flags.set(pkt->flags & (VALID_ADDR|VALID_SIZE));
804
805 // should we allocate space for data, or not, the express
806 // snoops do not need to carry any data as they only serve to
807 // co-ordinate state changes
808 if (alloc_data) {
809 // even if asked to allocate data, if the original packet
810 // holds static data, then the sender will not be doing
811 // any memcpy on receiving the response, thus we simply
812 // carry the pointer forward
813 if (pkt->flags.isSet(STATIC_DATA)) {
814 data = pkt->data;
815 flags.set(STATIC_DATA);
816 } else {
817 allocate();
818 }
819 }
820 }
821
822 /**
823 * Generate the appropriate read MemCmd based on the Request flags.
824 */
825 static MemCmd
826 makeReadCmd(const RequestPtr &req)
827 {
828 if (req->isLLSC())
829 return MemCmd::LoadLockedReq;
830 else if (req->isPrefetch())
831 return MemCmd::SoftPFReq;
832 else
833 return MemCmd::ReadReq;
834 }
835
836 /**
837 * Generate the appropriate write MemCmd based on the Request flags.
838 */
839 static MemCmd
840 makeWriteCmd(const RequestPtr &req)
841 {
842 if (req->isLLSC())
843 return MemCmd::StoreCondReq;
844 else if (req->isSwap() || req->isAtomic())
845 return MemCmd::SwapReq;
846 else if (req->isCacheInvalidate()) {
847 return req->isCacheClean() ? MemCmd::CleanInvalidReq :
848 MemCmd::InvalidateReq;
849 } else if (req->isCacheClean()) {
850 return MemCmd::CleanSharedReq;
851 } else
852 return MemCmd::WriteReq;
853 }
854
855 /**
856 * Constructor-like methods that return Packets based on Request objects.
857 * Fine-tune the MemCmd type if it's not a vanilla read or write.
858 */
859 static PacketPtr
860 createRead(const RequestPtr &req)
861 {
862 return new Packet(req, makeReadCmd(req));
863 }
864
865 static PacketPtr
866 createWrite(const RequestPtr &req)
867 {
868 return new Packet(req, makeWriteCmd(req));
869 }
870
871 /**
872 * clean up packet variables
873 */
874 ~Packet()
875 {
876 deleteData();
877 }
878
879 /**
880 * Take a request packet and modify it in place to be suitable for
881 * returning as a response to that request.
882 */
883 void
884 makeResponse()
885 {
886 assert(needsResponse());
887 assert(isRequest());
888 cmd = cmd.responseCommand();
889
890 // responses are never express, even if the snoop that
891 // triggered them was
892 flags.clear(EXPRESS_SNOOP);
893 }
894
895 void
896 makeAtomicResponse()
897 {
898 makeResponse();
899 }
900
901 void
902 makeTimingResponse()
903 {
904 makeResponse();
905 }
906
907 void
908 setFunctionalResponseStatus(bool success)
909 {
910 if (!success) {
911 if (isWrite()) {
912 cmd = MemCmd::FunctionalWriteError;
913 } else {
914 cmd = MemCmd::FunctionalReadError;
915 }
916 }
917 }
918
919 void
920 setSize(unsigned size)
921 {
922 assert(!flags.isSet(VALID_SIZE));
923
924 this->size = size;
925 flags.set(VALID_SIZE);
926 }
927
928
929 public:
930 /**
931 * @{
932 * @name Data accessor mehtods
933 */
934
935 /**
936 * Set the data pointer to the following value that should not be
937 * freed. Static data allows us to do a single memcpy even if
938 * multiple packets are required to get from source to destination
939 * and back. In essence the pointer is set calling dataStatic on
940 * the original packet, and whenever this packet is copied and
941 * forwarded the same pointer is passed on. When a packet
942 * eventually reaches the destination holding the data, it is
943 * copied once into the location originally set. On the way back
944 * to the source, no copies are necessary.
945 */
946 template <typename T>
947 void
948 dataStatic(T *p)
949 {
950 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
951 data = (PacketDataPtr)p;
952 flags.set(STATIC_DATA);
953 }
954
955 /**
956 * Set the data pointer to the following value that should not be
957 * freed. This version of the function allows the pointer passed
958 * to us to be const. To avoid issues down the line we cast the
959 * constness away, the alternative would be to keep both a const
960 * and non-const data pointer and cleverly choose between
961 * them. Note that this is only allowed for static data.
962 */
963 template <typename T>
964 void
965 dataStaticConst(const T *p)
966 {
967 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
968 data = const_cast<PacketDataPtr>(p);
969 flags.set(STATIC_DATA);
970 }
971
972 /**
973 * Set the data pointer to a value that should have delete []
974 * called on it. Dynamic data is local to this packet, and as the
975 * packet travels from source to destination, forwarded packets
976 * will allocate their own data. When a packet reaches the final
977 * destination it will populate the dynamic data of that specific
978 * packet, and on the way back towards the source, memcpy will be
979 * invoked in every step where a new packet was created e.g. in
980 * the caches. Ultimately when the response reaches the source a
981 * final memcpy is needed to extract the data from the packet
982 * before it is deallocated.
983 */
984 template <typename T>
985 void
986 dataDynamic(T *p)
987 {
988 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
989 data = (PacketDataPtr)p;
990 flags.set(DYNAMIC_DATA);
991 }
992
993 /**
994 * get a pointer to the data ptr.
995 */
996 template <typename T>
997 T*
998 getPtr()
999 {
1000 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
1001 return (T*)data;
1002 }
1003
1004 template <typename T>
1005 const T*
1006 getConstPtr() const
1007 {
1008 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
1009 return (const T*)data;
1010 }
1011
1012 /**
1013 * Get the data in the packet byte swapped from big endian to
1014 * host endian.
1015 */
1016 template <typename T>
1017 T getBE() const;
1018
1019 /**
1020 * Get the data in the packet byte swapped from little endian to
1021 * host endian.
1022 */
1023 template <typename T>
1024 T getLE() const;
1025
1026 /**
1027 * Get the data in the packet byte swapped from the specified
1028 * endianness.
1029 */
1030 template <typename T>
1031 T get(ByteOrder endian) const;
1032
1033 /**
1034 * Get the data in the packet byte swapped from guest to host
1035 * endian.
1036 */
1037 template <typename T>
1038 T get() const;
1039
1040 /** Set the value in the data pointer to v as big endian. */
1041 template <typename T>
1042 void setBE(T v);
1043
1044 /** Set the value in the data pointer to v as little endian. */
1045 template <typename T>
1046 void setLE(T v);
1047
1048 /**
1049 * Set the value in the data pointer to v using the specified
1050 * endianness.
1051 */
1052 template <typename T>
1053 void set(T v, ByteOrder endian);
1054
1055 /** Set the value in the data pointer to v as guest endian. */
1056 template <typename T>
1057 void set(T v);
1058
1059
1060 /**
1061 * Get the data in the packet byte swapped from the specified
1062 * endianness and zero-extended to 64 bits.
1063 */
1064 uint64_t getUintX(ByteOrder endian) const;
1065
1066 /**
1067 * Set the value in the word w after truncating it to the length
1068 * of the packet and then byteswapping it to the desired
1069 * endianness.
1070 */
1071 void setUintX(uint64_t w, ByteOrder endian);
1072
1073 /**
1074 * Copy data into the packet from the provided pointer.
1075 */
1076 void
1077 setData(const uint8_t *p)
1078 {
1079 // we should never be copying data onto itself, which means we
1080 // must idenfity packets with static data, as they carry the
1081 // same pointer from source to destination and back
1082 assert(p != getPtr<uint8_t>() || flags.isSet(STATIC_DATA));
1083
1084 if (p != getPtr<uint8_t>())
1085 // for packet with allocated dynamic data, we copy data from
1086 // one to the other, e.g. a forwarded response to a response
1087 std::memcpy(getPtr<uint8_t>(), p, getSize());
1088 }
1089
1090 /**
1091 * Copy data into the packet from the provided block pointer,
1092 * which is aligned to the given block size.
1093 */
1094 void
1095 setDataFromBlock(const uint8_t *blk_data, int blkSize)
1096 {
1097 setData(blk_data + getOffset(blkSize));
1098 }
1099
1100 /**
1101 * Copy data from the packet to the memory at the provided pointer.
1102 * @param p Pointer to which data will be copied.
1103 */
1104 void
1105 writeData(uint8_t *p) const
1106 {
1107 std::memcpy(p, getConstPtr<uint8_t>(), getSize());
1108 }
1109
1110 /**
1111 * Copy data from the packet to the provided block pointer, which
1112 * is aligned to the given block size.
1113 * @param blk_data Pointer to block to which data will be copied.
1114 * @param blkSize Block size in bytes.
1115 */
1116 void
1117 writeDataToBlock(uint8_t *blk_data, int blkSize) const
1118 {
1119 writeData(blk_data + getOffset(blkSize));
1120 }
1121
1122 /**
1123 * delete the data pointed to in the data pointer. Ok to call to
1124 * matter how data was allocted.
1125 */
1126 void
1127 deleteData()
1128 {
1129 if (flags.isSet(DYNAMIC_DATA))
1130 delete [] data;
1131
1132 flags.clear(STATIC_DATA|DYNAMIC_DATA);
1133 data = NULL;
1134 }
1135
1136 /** Allocate memory for the packet. */
1137 void
1138 allocate()
1139 {
1140 // if either this command or the response command has a data
1141 // payload, actually allocate space
1142 if (hasData() || hasRespData()) {
1143 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
1144 flags.set(DYNAMIC_DATA);
1145 data = new uint8_t[getSize()];
1146 }
1147 }
1148
1149 /** @} */
1150
1151 private: // Private data accessor methods
1152 /** Get the data in the packet without byte swapping. */
1153 template <typename T>
1154 T getRaw() const;
1155
1156 /** Set the value in the data pointer to v without byte swapping. */
1157 template <typename T>
1158 void setRaw(T v);
1159
1160 public:
1161 /**
1162 * Check a functional request against a memory value stored in
1163 * another packet (i.e. an in-transit request or
1164 * response). Returns true if the current packet is a read, and
1165 * the other packet provides the data, which is then copied to the
1166 * current packet. If the current packet is a write, and the other
1167 * packet intersects this one, then we update the data
1168 * accordingly.
1169 */
1170 bool
| 1/*
2 * Copyright (c) 2012-2018 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 * Nikos Nikoleris
46 */
47
48/**
49 * @file
50 * Declaration of the Packet class.
51 */
52
53#ifndef __MEM_PACKET_HH__
54#define __MEM_PACKET_HH__
55
56#include <bitset>
57#include <cassert>
58#include <list>
59
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"
68
69class Packet;
70typedef Packet *PacketPtr;
71typedef uint8_t* PacketDataPtr;
72typedef std::list<PacketPtr> PacketList;
73typedef uint64_t PacketId;
74
75class MemCmd
76{
77 friend class Packet;
78
79 public:
80 /**
81 * List of all commands associated with a packet.
82 */
83 enum Command
84 {
85 InvalidCmd,
86 ReadReq,
87 ReadResp,
88 ReadRespWithInvalidate,
89 WriteReq,
90 WriteResp,
91 WritebackDirty,
92 WritebackClean,
93 WriteClean, // writes dirty data below without evicting
94 CleanEvict,
95 SoftPFReq,
96 HardPFReq,
97 SoftPFResp,
98 HardPFResp,
99 WriteLineReq,
100 UpgradeReq,
101 SCUpgradeReq, // Special "weak" upgrade for StoreCond
102 UpgradeResp,
103 SCUpgradeFailReq, // Failed SCUpgradeReq in MSHR (never sent)
104 UpgradeFailResp, // Valid for SCUpgradeReq only
105 ReadExReq,
106 ReadExResp,
107 ReadCleanReq,
108 ReadSharedReq,
109 LoadLockedReq,
110 StoreCondReq,
111 StoreCondFailReq, // Failed StoreCondReq in MSHR (never sent)
112 StoreCondResp,
113 SwapReq,
114 SwapResp,
115 MessageReq,
116 MessageResp,
117 MemFenceReq,
118 MemFenceResp,
119 CleanSharedReq,
120 CleanSharedResp,
121 CleanInvalidReq,
122 CleanInvalidResp,
123 // Error responses
124 // @TODO these should be classified as responses rather than
125 // requests; coding them as requests initially for backwards
126 // compatibility
127 InvalidDestError, // packet dest field invalid
128 BadAddressError, // memory address invalid
129 FunctionalReadError, // unable to fulfill functional read
130 FunctionalWriteError, // unable to fulfill functional write
131 // Fake simulator-only commands
132 PrintReq, // Print state matching address
133 FlushReq, //request for a cache flush
134 InvalidateReq, // request for address to be invalidated
135 InvalidateResp,
136 NUM_MEM_CMDS
137 };
138
139 private:
140 /**
141 * List of command attributes.
142 */
143 enum Attribute
144 {
145 IsRead, //!< Data flows from responder to requester
146 IsWrite, //!< Data flows from requester to responder
147 IsUpgrade,
148 IsInvalidate,
149 IsClean, //!< Cleans any existing dirty blocks
150 NeedsWritable, //!< Requires writable copy to complete in-cache
151 IsRequest, //!< Issued by requester
152 IsResponse, //!< Issue by responder
153 NeedsResponse, //!< Requester needs response from target
154 IsEviction,
155 IsSWPrefetch,
156 IsHWPrefetch,
157 IsLlsc, //!< Alpha/MIPS LL or SC access
158 HasData, //!< There is an associated payload
159 IsError, //!< Error response
160 IsPrint, //!< Print state matching address (for debugging)
161 IsFlush, //!< Flush the address from caches
162 FromCache, //!< Request originated from a caching agent
163 NUM_COMMAND_ATTRIBUTES
164 };
165
166 /**
167 * Structure that defines attributes and other data associated
168 * with a Command.
169 */
170 struct CommandInfo
171 {
172 /// Set of attribute flags.
173 const std::bitset<NUM_COMMAND_ATTRIBUTES> attributes;
174 /// Corresponding response for requests; InvalidCmd if no
175 /// response is applicable.
176 const Command response;
177 /// String representation (for printing)
178 const std::string str;
179 };
180
181 /// Array to map Command enum to associated info.
182 static const CommandInfo commandInfo[];
183
184 private:
185
186 Command cmd;
187
188 bool
189 testCmdAttrib(MemCmd::Attribute attrib) const
190 {
191 return commandInfo[cmd].attributes[attrib] != 0;
192 }
193
194 public:
195
196 bool isRead() const { return testCmdAttrib(IsRead); }
197 bool isWrite() const { return testCmdAttrib(IsWrite); }
198 bool isUpgrade() const { return testCmdAttrib(IsUpgrade); }
199 bool isRequest() const { return testCmdAttrib(IsRequest); }
200 bool isResponse() const { return testCmdAttrib(IsResponse); }
201 bool needsWritable() const { return testCmdAttrib(NeedsWritable); }
202 bool needsResponse() const { return testCmdAttrib(NeedsResponse); }
203 bool isInvalidate() const { return testCmdAttrib(IsInvalidate); }
204 bool isEviction() const { return testCmdAttrib(IsEviction); }
205 bool isClean() const { return testCmdAttrib(IsClean); }
206 bool fromCache() const { return testCmdAttrib(FromCache); }
207
208 /**
209 * A writeback is an eviction that carries data.
210 */
211 bool isWriteback() const { return testCmdAttrib(IsEviction) &&
212 testCmdAttrib(HasData); }
213
214 /**
215 * Check if this particular packet type carries payload data. Note
216 * that this does not reflect if the data pointer of the packet is
217 * valid or not.
218 */
219 bool hasData() const { return testCmdAttrib(HasData); }
220 bool isLLSC() const { return testCmdAttrib(IsLlsc); }
221 bool isSWPrefetch() const { return testCmdAttrib(IsSWPrefetch); }
222 bool isHWPrefetch() const { return testCmdAttrib(IsHWPrefetch); }
223 bool isPrefetch() const { return testCmdAttrib(IsSWPrefetch) ||
224 testCmdAttrib(IsHWPrefetch); }
225 bool isError() const { return testCmdAttrib(IsError); }
226 bool isPrint() const { return testCmdAttrib(IsPrint); }
227 bool isFlush() const { return testCmdAttrib(IsFlush); }
228
229 Command
230 responseCommand() const
231 {
232 return commandInfo[cmd].response;
233 }
234
235 /// Return the string to a cmd given by idx.
236 const std::string &toString() const { return commandInfo[cmd].str; }
237 int toInt() const { return (int)cmd; }
238
239 MemCmd(Command _cmd) : cmd(_cmd) { }
240 MemCmd(int _cmd) : cmd((Command)_cmd) { }
241 MemCmd() : cmd(InvalidCmd) { }
242
243 bool operator==(MemCmd c2) const { return (cmd == c2.cmd); }
244 bool operator!=(MemCmd c2) const { return (cmd != c2.cmd); }
245};
246
247/**
248 * A Packet is used to encapsulate a transfer between two objects in
249 * the memory system (e.g., the L1 and L2 cache). (In contrast, a
250 * single Request travels all the way from the requester to the
251 * ultimate destination and back, possibly being conveyed by several
252 * different Packets along the way.)
253 */
254class Packet : public Printable
255{
256 public:
257 typedef uint32_t FlagsType;
258 typedef ::Flags<FlagsType> Flags;
259
260 private:
261
262 enum : FlagsType {
263 // Flags to transfer across when copying a packet
264 COPY_FLAGS = 0x0000003F,
265
266 // Does this packet have sharers (which means it should not be
267 // considered writable) or not. See setHasSharers below.
268 HAS_SHARERS = 0x00000001,
269
270 // Special control flags
271 /// Special timing-mode atomic snoop for multi-level coherence.
272 EXPRESS_SNOOP = 0x00000002,
273
274 /// Allow a responding cache to inform the cache hierarchy
275 /// that it had a writable copy before responding. See
276 /// setResponderHadWritable below.
277 RESPONDER_HAD_WRITABLE = 0x00000004,
278
279 // Snoop co-ordination flag to indicate that a cache is
280 // responding to a snoop. See setCacheResponding below.
281 CACHE_RESPONDING = 0x00000008,
282
283 // The writeback/writeclean should be propagated further
284 // downstream by the receiver
285 WRITE_THROUGH = 0x00000010,
286
287 // Response co-ordination flag for cache maintenance
288 // operations
289 SATISFIED = 0x00000020,
290
291 /// Are the 'addr' and 'size' fields valid?
292 VALID_ADDR = 0x00000100,
293 VALID_SIZE = 0x00000200,
294
295 /// Is the data pointer set to a value that shouldn't be freed
296 /// when the packet is destroyed?
297 STATIC_DATA = 0x00001000,
298 /// The data pointer points to a value that should be freed when
299 /// the packet is destroyed. The pointer is assumed to be pointing
300 /// to an array, and delete [] is consequently called
301 DYNAMIC_DATA = 0x00002000,
302
303 /// suppress the error if this packet encounters a functional
304 /// access failure.
305 SUPPRESS_FUNC_ERROR = 0x00008000,
306
307 // Signal block present to squash prefetch and cache evict packets
308 // through express snoop flag
309 BLOCK_CACHED = 0x00010000
310 };
311
312 Flags flags;
313
314 public:
315 typedef MemCmd::Command Command;
316
317 /// The command field of the packet.
318 MemCmd cmd;
319
320 const PacketId id;
321
322 /// A pointer to the original request.
323 RequestPtr req;
324
325 private:
326 /**
327 * A pointer to the data being transferred. It can be different
328 * sizes at each level of the hierarchy so it belongs to the
329 * packet, not request. This may or may not be populated when a
330 * responder receives the packet. If not populated memory should
331 * be allocated.
332 */
333 PacketDataPtr data;
334
335 /// The address of the request. This address could be virtual or
336 /// physical, depending on the system configuration.
337 Addr addr;
338
339 /// True if the request targets the secure memory space.
340 bool _isSecure;
341
342 /// The size of the request or transfer.
343 unsigned size;
344
345 /**
346 * Track the bytes found that satisfy a functional read.
347 */
348 std::vector<bool> bytesValid;
349
350 public:
351
352 /**
353 * The extra delay from seeing the packet until the header is
354 * transmitted. This delay is used to communicate the crossbar
355 * forwarding latency to the neighbouring object (e.g. a cache)
356 * that actually makes the packet wait. As the delay is relative,
357 * a 32-bit unsigned should be sufficient.
358 */
359 uint32_t headerDelay;
360
361 /**
362 * Keep track of the extra delay incurred by snooping upwards
363 * before sending a request down the memory system. This is used
364 * by the coherent crossbar to account for the additional request
365 * delay.
366 */
367 uint32_t snoopDelay;
368
369 /**
370 * The extra pipelining delay from seeing the packet until the end of
371 * payload is transmitted by the component that provided it (if
372 * any). This includes the header delay. Similar to the header
373 * delay, this is used to make up for the fact that the
374 * crossbar does not make the packet wait. As the delay is
375 * relative, a 32-bit unsigned should be sufficient.
376 */
377 uint32_t payloadDelay;
378
379 /**
380 * A virtual base opaque structure used to hold state associated
381 * with the packet (e.g., an MSHR), specific to a MemObject that
382 * sees the packet. A pointer to this state is returned in the
383 * packet's response so that the MemObject in question can quickly
384 * look up the state needed to process it. A specific subclass
385 * would be derived from this to carry state specific to a
386 * particular sending device.
387 *
388 * As multiple MemObjects may add their SenderState throughout the
389 * memory system, the SenderStates create a stack, where a
390 * MemObject can add a new Senderstate, as long as the
391 * predecessing SenderState is restored when the response comes
392 * back. For this reason, the predecessor should always be
393 * populated with the current SenderState of a packet before
394 * modifying the senderState field in the request packet.
395 */
396 struct SenderState
397 {
398 SenderState* predecessor;
399 SenderState() : predecessor(NULL) {}
400 virtual ~SenderState() {}
401 };
402
403 /**
404 * Object used to maintain state of a PrintReq. The senderState
405 * field of a PrintReq should always be of this type.
406 */
407 class PrintReqState : public SenderState
408 {
409 private:
410 /**
411 * An entry in the label stack.
412 */
413 struct LabelStackEntry
414 {
415 const std::string label;
416 std::string *prefix;
417 bool labelPrinted;
418 LabelStackEntry(const std::string &_label, std::string *_prefix);
419 };
420
421 typedef std::list<LabelStackEntry> LabelStack;
422 LabelStack labelStack;
423
424 std::string *curPrefixPtr;
425
426 public:
427 std::ostream &os;
428 const int verbosity;
429
430 PrintReqState(std::ostream &os, int verbosity = 0);
431 ~PrintReqState();
432
433 /**
434 * Returns the current line prefix.
435 */
436 const std::string &curPrefix() { return *curPrefixPtr; }
437
438 /**
439 * Push a label onto the label stack, and prepend the given
440 * prefix string onto the current prefix. Labels will only be
441 * printed if an object within the label's scope is printed.
442 */
443 void pushLabel(const std::string &lbl,
444 const std::string &prefix = " ");
445
446 /**
447 * Pop a label off the label stack.
448 */
449 void popLabel();
450
451 /**
452 * Print all of the pending unprinted labels on the
453 * stack. Called by printObj(), so normally not called by
454 * users unless bypassing printObj().
455 */
456 void printLabels();
457
458 /**
459 * Print a Printable object to os, because it matched the
460 * address on a PrintReq.
461 */
462 void printObj(Printable *obj);
463 };
464
465 /**
466 * This packet's sender state. Devices should use dynamic_cast<>
467 * to cast to the state appropriate to the sender. The intent of
468 * this variable is to allow a device to attach extra information
469 * to a request. A response packet must return the sender state
470 * that was attached to the original request (even if a new packet
471 * is created).
472 */
473 SenderState *senderState;
474
475 /**
476 * Push a new sender state to the packet and make the current
477 * sender state the predecessor of the new one. This should be
478 * prefered over direct manipulation of the senderState member
479 * variable.
480 *
481 * @param sender_state SenderState to push at the top of the stack
482 */
483 void pushSenderState(SenderState *sender_state);
484
485 /**
486 * Pop the top of the state stack and return a pointer to it. This
487 * assumes the current sender state is not NULL. This should be
488 * preferred over direct manipulation of the senderState member
489 * variable.
490 *
491 * @return The current top of the stack
492 */
493 SenderState *popSenderState();
494
495 /**
496 * Go through the sender state stack and return the first instance
497 * that is of type T (as determined by a dynamic_cast). If there
498 * is no sender state of type T, NULL is returned.
499 *
500 * @return The topmost state of type T
501 */
502 template <typename T>
503 T * findNextSenderState() const
504 {
505 T *t = NULL;
506 SenderState* sender_state = senderState;
507 while (t == NULL && sender_state != NULL) {
508 t = dynamic_cast<T*>(sender_state);
509 sender_state = sender_state->predecessor;
510 }
511 return t;
512 }
513
514 /// Return the string name of the cmd field (for debugging and
515 /// tracing).
516 const std::string &cmdString() const { return cmd.toString(); }
517
518 /// Return the index of this command.
519 inline int cmdToIndex() const { return cmd.toInt(); }
520
521 bool isRead() const { return cmd.isRead(); }
522 bool isWrite() const { return cmd.isWrite(); }
523 bool isUpgrade() const { return cmd.isUpgrade(); }
524 bool isRequest() const { return cmd.isRequest(); }
525 bool isResponse() const { return cmd.isResponse(); }
526 bool needsWritable() const
527 {
528 // we should never check if a response needsWritable, the
529 // request has this flag, and for a response we should rather
530 // look at the hasSharers flag (if not set, the response is to
531 // be considered writable)
532 assert(isRequest());
533 return cmd.needsWritable();
534 }
535 bool needsResponse() const { return cmd.needsResponse(); }
536 bool isInvalidate() const { return cmd.isInvalidate(); }
537 bool isEviction() const { return cmd.isEviction(); }
538 bool isClean() const { return cmd.isClean(); }
539 bool fromCache() const { return cmd.fromCache(); }
540 bool isWriteback() const { return cmd.isWriteback(); }
541 bool hasData() const { return cmd.hasData(); }
542 bool hasRespData() const
543 {
544 MemCmd resp_cmd = cmd.responseCommand();
545 return resp_cmd.hasData();
546 }
547 bool isLLSC() const { return cmd.isLLSC(); }
548 bool isError() const { return cmd.isError(); }
549 bool isPrint() const { return cmd.isPrint(); }
550 bool isFlush() const { return cmd.isFlush(); }
551
552 //@{
553 /// Snoop flags
554 /**
555 * Set the cacheResponding flag. This is used by the caches to
556 * signal another cache that they are responding to a request. A
557 * cache will only respond to snoops if it has the line in either
558 * Modified or Owned state. Note that on snoop hits we always pass
559 * the line as Modified and never Owned. In the case of an Owned
560 * line we proceed to invalidate all other copies.
561 *
562 * On a cache fill (see Cache::handleFill), we check hasSharers
563 * first, ignoring the cacheResponding flag if hasSharers is set.
564 * A line is consequently allocated as:
565 *
566 * hasSharers cacheResponding state
567 * true false Shared
568 * true true Shared
569 * false false Exclusive
570 * false true Modified
571 */
572 void setCacheResponding()
573 {
574 assert(isRequest());
575 assert(!flags.isSet(CACHE_RESPONDING));
576 flags.set(CACHE_RESPONDING);
577 }
578 bool cacheResponding() const { return flags.isSet(CACHE_RESPONDING); }
579 /**
580 * On fills, the hasSharers flag is used by the caches in
581 * combination with the cacheResponding flag, as clarified
582 * above. If the hasSharers flag is not set, the packet is passing
583 * writable. Thus, a response from a memory passes the line as
584 * writable by default.
585 *
586 * The hasSharers flag is also used by upstream caches to inform a
587 * downstream cache that they have the block (by calling
588 * setHasSharers on snoop request packets that hit in upstream
589 * cachs tags or MSHRs). If the snoop packet has sharers, a
590 * downstream cache is prevented from passing a dirty line upwards
591 * if it was not explicitly asked for a writable copy. See
592 * Cache::satisfyCpuSideRequest.
593 *
594 * The hasSharers flag is also used on writebacks, in
595 * combination with the WritbackClean or WritebackDirty commands,
596 * to allocate the block downstream either as:
597 *
598 * command hasSharers state
599 * WritebackDirty false Modified
600 * WritebackDirty true Owned
601 * WritebackClean false Exclusive
602 * WritebackClean true Shared
603 */
604 void setHasSharers() { flags.set(HAS_SHARERS); }
605 bool hasSharers() const { return flags.isSet(HAS_SHARERS); }
606 //@}
607
608 /**
609 * The express snoop flag is used for two purposes. Firstly, it is
610 * used to bypass flow control for normal (non-snoop) requests
611 * going downstream in the memory system. In cases where a cache
612 * is responding to a snoop from another cache (it had a dirty
613 * line), but the line is not writable (and there are possibly
614 * other copies), the express snoop flag is set by the downstream
615 * cache to invalidate all other copies in zero time. Secondly,
616 * the express snoop flag is also set to be able to distinguish
617 * snoop packets that came from a downstream cache, rather than
618 * snoop packets from neighbouring caches.
619 */
620 void setExpressSnoop() { flags.set(EXPRESS_SNOOP); }
621 bool isExpressSnoop() const { return flags.isSet(EXPRESS_SNOOP); }
622
623 /**
624 * On responding to a snoop request (which only happens for
625 * Modified or Owned lines), make sure that we can transform an
626 * Owned response to a Modified one. If this flag is not set, the
627 * responding cache had the line in the Owned state, and there are
628 * possibly other Shared copies in the memory system. A downstream
629 * cache helps in orchestrating the invalidation of these copies
630 * by sending out the appropriate express snoops.
631 */
632 void setResponderHadWritable()
633 {
634 assert(cacheResponding());
635 assert(!responderHadWritable());
636 flags.set(RESPONDER_HAD_WRITABLE);
637 }
638 bool responderHadWritable() const
639 { return flags.isSet(RESPONDER_HAD_WRITABLE); }
640
641 /**
642 * A writeback/writeclean cmd gets propagated further downstream
643 * by the receiver when the flag is set.
644 */
645 void setWriteThrough()
646 {
647 assert(cmd.isWrite() &&
648 (cmd.isEviction() || cmd == MemCmd::WriteClean));
649 flags.set(WRITE_THROUGH);
650 }
651 void clearWriteThrough() { flags.clear(WRITE_THROUGH); }
652 bool writeThrough() const { return flags.isSet(WRITE_THROUGH); }
653
654 /**
655 * Set when a request hits in a cache and the cache is not going
656 * to respond. This is used by the crossbar to coordinate
657 * responses for cache maintenance operations.
658 */
659 void setSatisfied()
660 {
661 assert(cmd.isClean());
662 assert(!flags.isSet(SATISFIED));
663 flags.set(SATISFIED);
664 }
665 bool satisfied() const { return flags.isSet(SATISFIED); }
666
667 void setSuppressFuncError() { flags.set(SUPPRESS_FUNC_ERROR); }
668 bool suppressFuncError() const { return flags.isSet(SUPPRESS_FUNC_ERROR); }
669 void setBlockCached() { flags.set(BLOCK_CACHED); }
670 bool isBlockCached() const { return flags.isSet(BLOCK_CACHED); }
671 void clearBlockCached() { flags.clear(BLOCK_CACHED); }
672
673 // Network error conditions... encapsulate them as methods since
674 // their encoding keeps changing (from result field to command
675 // field, etc.)
676 void
677 setBadAddress()
678 {
679 assert(isResponse());
680 cmd = MemCmd::BadAddressError;
681 }
682
683 void copyError(Packet *pkt) { assert(pkt->isError()); cmd = pkt->cmd; }
684
685 Addr getAddr() const { assert(flags.isSet(VALID_ADDR)); return addr; }
686 /**
687 * Update the address of this packet mid-transaction. This is used
688 * by the address mapper to change an already set address to a new
689 * one based on the system configuration. It is intended to remap
690 * an existing address, so it asserts that the current address is
691 * valid.
692 */
693 void setAddr(Addr _addr) { assert(flags.isSet(VALID_ADDR)); addr = _addr; }
694
695 unsigned getSize() const { assert(flags.isSet(VALID_SIZE)); return size; }
696
697 Addr getOffset(unsigned int blk_size) const
698 {
699 return getAddr() & Addr(blk_size - 1);
700 }
701
702 Addr getBlockAddr(unsigned int blk_size) const
703 {
704 return getAddr() & ~(Addr(blk_size - 1));
705 }
706
707 bool isSecure() const
708 {
709 assert(flags.isSet(VALID_ADDR));
710 return _isSecure;
711 }
712
713 /**
714 * Accessor function to atomic op.
715 */
716 AtomicOpFunctor *getAtomicOp() const { return req->getAtomicOpFunctor(); }
717 bool isAtomicOp() const { return req->isAtomic(); }
718
719 /**
720 * It has been determined that the SC packet should successfully update
721 * memory. Therefore, convert this SC packet to a normal write.
722 */
723 void
724 convertScToWrite()
725 {
726 assert(isLLSC());
727 assert(isWrite());
728 cmd = MemCmd::WriteReq;
729 }
730
731 /**
732 * When ruby is in use, Ruby will monitor the cache line and the
733 * phys memory should treat LL ops as normal reads.
734 */
735 void
736 convertLlToRead()
737 {
738 assert(isLLSC());
739 assert(isRead());
740 cmd = MemCmd::ReadReq;
741 }
742
743 /**
744 * Constructor. Note that a Request object must be constructed
745 * first, but the Requests's physical address and size fields need
746 * not be valid. The command must be supplied.
747 */
748 Packet(const RequestPtr &_req, MemCmd _cmd)
749 : cmd(_cmd), id((PacketId)_req.get()), req(_req), data(nullptr),
750 addr(0), _isSecure(false), size(0), headerDelay(0), snoopDelay(0),
751 payloadDelay(0), senderState(NULL)
752 {
753 if (req->hasPaddr()) {
754 addr = req->getPaddr();
755 flags.set(VALID_ADDR);
756 _isSecure = req->isSecure();
757 }
758 if (req->hasSize()) {
759 size = req->getSize();
760 flags.set(VALID_SIZE);
761 }
762 }
763
764 /**
765 * Alternate constructor if you are trying to create a packet with
766 * a request that is for a whole block, not the address from the
767 * req. this allows for overriding the size/addr of the req.
768 */
769 Packet(const RequestPtr &_req, MemCmd _cmd, int _blkSize, PacketId _id = 0)
770 : cmd(_cmd), id(_id ? _id : (PacketId)_req.get()), req(_req),
771 data(nullptr), addr(0), _isSecure(false), headerDelay(0),
772 snoopDelay(0), payloadDelay(0), senderState(NULL)
773 {
774 if (req->hasPaddr()) {
775 addr = req->getPaddr() & ~(_blkSize - 1);
776 flags.set(VALID_ADDR);
777 _isSecure = req->isSecure();
778 }
779 size = _blkSize;
780 flags.set(VALID_SIZE);
781 }
782
783 /**
784 * Alternate constructor for copying a packet. Copy all fields
785 * *except* if the original packet's data was dynamic, don't copy
786 * that, as we can't guarantee that the new packet's lifetime is
787 * less than that of the original packet. In this case the new
788 * packet should allocate its own data.
789 */
790 Packet(const PacketPtr pkt, bool clear_flags, bool alloc_data)
791 : cmd(pkt->cmd), id(pkt->id), req(pkt->req),
792 data(nullptr),
793 addr(pkt->addr), _isSecure(pkt->_isSecure), size(pkt->size),
794 bytesValid(pkt->bytesValid),
795 headerDelay(pkt->headerDelay),
796 snoopDelay(0),
797 payloadDelay(pkt->payloadDelay),
798 senderState(pkt->senderState)
799 {
800 if (!clear_flags)
801 flags.set(pkt->flags & COPY_FLAGS);
802
803 flags.set(pkt->flags & (VALID_ADDR|VALID_SIZE));
804
805 // should we allocate space for data, or not, the express
806 // snoops do not need to carry any data as they only serve to
807 // co-ordinate state changes
808 if (alloc_data) {
809 // even if asked to allocate data, if the original packet
810 // holds static data, then the sender will not be doing
811 // any memcpy on receiving the response, thus we simply
812 // carry the pointer forward
813 if (pkt->flags.isSet(STATIC_DATA)) {
814 data = pkt->data;
815 flags.set(STATIC_DATA);
816 } else {
817 allocate();
818 }
819 }
820 }
821
822 /**
823 * Generate the appropriate read MemCmd based on the Request flags.
824 */
825 static MemCmd
826 makeReadCmd(const RequestPtr &req)
827 {
828 if (req->isLLSC())
829 return MemCmd::LoadLockedReq;
830 else if (req->isPrefetch())
831 return MemCmd::SoftPFReq;
832 else
833 return MemCmd::ReadReq;
834 }
835
836 /**
837 * Generate the appropriate write MemCmd based on the Request flags.
838 */
839 static MemCmd
840 makeWriteCmd(const RequestPtr &req)
841 {
842 if (req->isLLSC())
843 return MemCmd::StoreCondReq;
844 else if (req->isSwap() || req->isAtomic())
845 return MemCmd::SwapReq;
846 else if (req->isCacheInvalidate()) {
847 return req->isCacheClean() ? MemCmd::CleanInvalidReq :
848 MemCmd::InvalidateReq;
849 } else if (req->isCacheClean()) {
850 return MemCmd::CleanSharedReq;
851 } else
852 return MemCmd::WriteReq;
853 }
854
855 /**
856 * Constructor-like methods that return Packets based on Request objects.
857 * Fine-tune the MemCmd type if it's not a vanilla read or write.
858 */
859 static PacketPtr
860 createRead(const RequestPtr &req)
861 {
862 return new Packet(req, makeReadCmd(req));
863 }
864
865 static PacketPtr
866 createWrite(const RequestPtr &req)
867 {
868 return new Packet(req, makeWriteCmd(req));
869 }
870
871 /**
872 * clean up packet variables
873 */
874 ~Packet()
875 {
876 deleteData();
877 }
878
879 /**
880 * Take a request packet and modify it in place to be suitable for
881 * returning as a response to that request.
882 */
883 void
884 makeResponse()
885 {
886 assert(needsResponse());
887 assert(isRequest());
888 cmd = cmd.responseCommand();
889
890 // responses are never express, even if the snoop that
891 // triggered them was
892 flags.clear(EXPRESS_SNOOP);
893 }
894
895 void
896 makeAtomicResponse()
897 {
898 makeResponse();
899 }
900
901 void
902 makeTimingResponse()
903 {
904 makeResponse();
905 }
906
907 void
908 setFunctionalResponseStatus(bool success)
909 {
910 if (!success) {
911 if (isWrite()) {
912 cmd = MemCmd::FunctionalWriteError;
913 } else {
914 cmd = MemCmd::FunctionalReadError;
915 }
916 }
917 }
918
919 void
920 setSize(unsigned size)
921 {
922 assert(!flags.isSet(VALID_SIZE));
923
924 this->size = size;
925 flags.set(VALID_SIZE);
926 }
927
928
929 public:
930 /**
931 * @{
932 * @name Data accessor mehtods
933 */
934
935 /**
936 * Set the data pointer to the following value that should not be
937 * freed. Static data allows us to do a single memcpy even if
938 * multiple packets are required to get from source to destination
939 * and back. In essence the pointer is set calling dataStatic on
940 * the original packet, and whenever this packet is copied and
941 * forwarded the same pointer is passed on. When a packet
942 * eventually reaches the destination holding the data, it is
943 * copied once into the location originally set. On the way back
944 * to the source, no copies are necessary.
945 */
946 template <typename T>
947 void
948 dataStatic(T *p)
949 {
950 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
951 data = (PacketDataPtr)p;
952 flags.set(STATIC_DATA);
953 }
954
955 /**
956 * Set the data pointer to the following value that should not be
957 * freed. This version of the function allows the pointer passed
958 * to us to be const. To avoid issues down the line we cast the
959 * constness away, the alternative would be to keep both a const
960 * and non-const data pointer and cleverly choose between
961 * them. Note that this is only allowed for static data.
962 */
963 template <typename T>
964 void
965 dataStaticConst(const T *p)
966 {
967 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
968 data = const_cast<PacketDataPtr>(p);
969 flags.set(STATIC_DATA);
970 }
971
972 /**
973 * Set the data pointer to a value that should have delete []
974 * called on it. Dynamic data is local to this packet, and as the
975 * packet travels from source to destination, forwarded packets
976 * will allocate their own data. When a packet reaches the final
977 * destination it will populate the dynamic data of that specific
978 * packet, and on the way back towards the source, memcpy will be
979 * invoked in every step where a new packet was created e.g. in
980 * the caches. Ultimately when the response reaches the source a
981 * final memcpy is needed to extract the data from the packet
982 * before it is deallocated.
983 */
984 template <typename T>
985 void
986 dataDynamic(T *p)
987 {
988 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
989 data = (PacketDataPtr)p;
990 flags.set(DYNAMIC_DATA);
991 }
992
993 /**
994 * get a pointer to the data ptr.
995 */
996 template <typename T>
997 T*
998 getPtr()
999 {
1000 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
1001 return (T*)data;
1002 }
1003
1004 template <typename T>
1005 const T*
1006 getConstPtr() const
1007 {
1008 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
1009 return (const T*)data;
1010 }
1011
1012 /**
1013 * Get the data in the packet byte swapped from big endian to
1014 * host endian.
1015 */
1016 template <typename T>
1017 T getBE() const;
1018
1019 /**
1020 * Get the data in the packet byte swapped from little endian to
1021 * host endian.
1022 */
1023 template <typename T>
1024 T getLE() const;
1025
1026 /**
1027 * Get the data in the packet byte swapped from the specified
1028 * endianness.
1029 */
1030 template <typename T>
1031 T get(ByteOrder endian) const;
1032
1033 /**
1034 * Get the data in the packet byte swapped from guest to host
1035 * endian.
1036 */
1037 template <typename T>
1038 T get() const;
1039
1040 /** Set the value in the data pointer to v as big endian. */
1041 template <typename T>
1042 void setBE(T v);
1043
1044 /** Set the value in the data pointer to v as little endian. */
1045 template <typename T>
1046 void setLE(T v);
1047
1048 /**
1049 * Set the value in the data pointer to v using the specified
1050 * endianness.
1051 */
1052 template <typename T>
1053 void set(T v, ByteOrder endian);
1054
1055 /** Set the value in the data pointer to v as guest endian. */
1056 template <typename T>
1057 void set(T v);
1058
1059
1060 /**
1061 * Get the data in the packet byte swapped from the specified
1062 * endianness and zero-extended to 64 bits.
1063 */
1064 uint64_t getUintX(ByteOrder endian) const;
1065
1066 /**
1067 * Set the value in the word w after truncating it to the length
1068 * of the packet and then byteswapping it to the desired
1069 * endianness.
1070 */
1071 void setUintX(uint64_t w, ByteOrder endian);
1072
1073 /**
1074 * Copy data into the packet from the provided pointer.
1075 */
1076 void
1077 setData(const uint8_t *p)
1078 {
1079 // we should never be copying data onto itself, which means we
1080 // must idenfity packets with static data, as they carry the
1081 // same pointer from source to destination and back
1082 assert(p != getPtr<uint8_t>() || flags.isSet(STATIC_DATA));
1083
1084 if (p != getPtr<uint8_t>())
1085 // for packet with allocated dynamic data, we copy data from
1086 // one to the other, e.g. a forwarded response to a response
1087 std::memcpy(getPtr<uint8_t>(), p, getSize());
1088 }
1089
1090 /**
1091 * Copy data into the packet from the provided block pointer,
1092 * which is aligned to the given block size.
1093 */
1094 void
1095 setDataFromBlock(const uint8_t *blk_data, int blkSize)
1096 {
1097 setData(blk_data + getOffset(blkSize));
1098 }
1099
1100 /**
1101 * Copy data from the packet to the memory at the provided pointer.
1102 * @param p Pointer to which data will be copied.
1103 */
1104 void
1105 writeData(uint8_t *p) const
1106 {
1107 std::memcpy(p, getConstPtr<uint8_t>(), getSize());
1108 }
1109
1110 /**
1111 * Copy data from the packet to the provided block pointer, which
1112 * is aligned to the given block size.
1113 * @param blk_data Pointer to block to which data will be copied.
1114 * @param blkSize Block size in bytes.
1115 */
1116 void
1117 writeDataToBlock(uint8_t *blk_data, int blkSize) const
1118 {
1119 writeData(blk_data + getOffset(blkSize));
1120 }
1121
1122 /**
1123 * delete the data pointed to in the data pointer. Ok to call to
1124 * matter how data was allocted.
1125 */
1126 void
1127 deleteData()
1128 {
1129 if (flags.isSet(DYNAMIC_DATA))
1130 delete [] data;
1131
1132 flags.clear(STATIC_DATA|DYNAMIC_DATA);
1133 data = NULL;
1134 }
1135
1136 /** Allocate memory for the packet. */
1137 void
1138 allocate()
1139 {
1140 // if either this command or the response command has a data
1141 // payload, actually allocate space
1142 if (hasData() || hasRespData()) {
1143 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
1144 flags.set(DYNAMIC_DATA);
1145 data = new uint8_t[getSize()];
1146 }
1147 }
1148
1149 /** @} */
1150
1151 private: // Private data accessor methods
1152 /** Get the data in the packet without byte swapping. */
1153 template <typename T>
1154 T getRaw() const;
1155
1156 /** Set the value in the data pointer to v without byte swapping. */
1157 template <typename T>
1158 void setRaw(T v);
1159
1160 public:
1161 /**
1162 * Check a functional request against a memory value stored in
1163 * another packet (i.e. an in-transit request or
1164 * response). Returns true if the current packet is a read, and
1165 * the other packet provides the data, which is then copied to the
1166 * current packet. If the current packet is a write, and the other
1167 * packet intersects this one, then we update the data
1168 * accordingly.
1169 */
1170 bool
|