1/*
2 * Copyright (c) 2012-2019 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/addr_range.hh"
61#include "base/cast.hh"
62#include "base/compiler.hh"
63#include "base/flags.hh"
64#include "base/logging.hh"
65#include "base/printable.hh"
66#include "base/types.hh"
67#include "config/the_isa.hh"
68#include "mem/request.hh"
69#include "sim/core.hh"
70
71class Packet;
72typedef Packet *PacketPtr;
73typedef uint8_t* PacketDataPtr;
74typedef std::list<PacketPtr> PacketList;
75typedef uint64_t PacketId;
76
77class MemCmd
78{
79 friend class Packet;
80
81 public:
82 /**
83 * List of all commands associated with a packet.
84 */
85 enum Command
86 {
87 InvalidCmd,
88 ReadReq,
89 ReadResp,
90 ReadRespWithInvalidate,
91 WriteReq,
92 WriteResp,
93 WritebackDirty,
94 WritebackClean,
95 WriteClean, // writes dirty data below without evicting
96 CleanEvict,
97 SoftPFReq,
98 SoftPFExReq,
99 HardPFReq,
100 SoftPFResp,
101 HardPFResp,
102 WriteLineReq,
103 UpgradeReq,
104 SCUpgradeReq, // Special "weak" upgrade for StoreCond
105 UpgradeResp,
106 SCUpgradeFailReq, // Failed SCUpgradeReq in MSHR (never sent)
107 UpgradeFailResp, // Valid for SCUpgradeReq only
108 ReadExReq,
109 ReadExResp,
110 ReadCleanReq,
111 ReadSharedReq,
112 LoadLockedReq,
113 StoreCondReq,
114 StoreCondFailReq, // Failed StoreCondReq in MSHR (never sent)
115 StoreCondResp,
116 SwapReq,
117 SwapResp,
118 MessageReq,
119 MessageResp,
120 MemFenceReq,
121 MemFenceResp,
122 CleanSharedReq,
123 CleanSharedResp,
124 CleanInvalidReq,
125 CleanInvalidResp,
126 // Error responses
127 // @TODO these should be classified as responses rather than
128 // requests; coding them as requests initially for backwards
129 // compatibility
130 InvalidDestError, // packet dest field invalid
131 BadAddressError, // memory address invalid
132 FunctionalReadError, // unable to fulfill functional read
133 FunctionalWriteError, // unable to fulfill functional write
134 // Fake simulator-only commands
135 PrintReq, // Print state matching address
136 FlushReq, //request for a cache flush
137 InvalidateReq, // request for address to be invalidated
138 InvalidateResp,
139 NUM_MEM_CMDS
140 };
141
142 private:
143 /**
144 * List of command attributes.
145 */
146 enum Attribute
147 {
148 IsRead, //!< Data flows from responder to requester
149 IsWrite, //!< Data flows from requester to responder
150 IsUpgrade,
151 IsInvalidate,
152 IsClean, //!< Cleans any existing dirty blocks
153 NeedsWritable, //!< Requires writable copy to complete in-cache
154 IsRequest, //!< Issued by requester
155 IsResponse, //!< Issue by responder
156 NeedsResponse, //!< Requester needs response from target
157 IsEviction,
158 IsSWPrefetch,
159 IsHWPrefetch,
160 IsLlsc, //!< Alpha/MIPS LL or SC access
161 HasData, //!< There is an associated payload
162 IsError, //!< Error response
163 IsPrint, //!< Print state matching address (for debugging)
164 IsFlush, //!< Flush the address from caches
165 FromCache, //!< Request originated from a caching agent
166 NUM_COMMAND_ATTRIBUTES
167 };
168
169 /**
170 * Structure that defines attributes and other data associated
171 * with a Command.
172 */
173 struct CommandInfo
174 {
175 /// Set of attribute flags.
176 const std::bitset<NUM_COMMAND_ATTRIBUTES> attributes;
177 /// Corresponding response for requests; InvalidCmd if no
178 /// response is applicable.
179 const Command response;
180 /// String representation (for printing)
181 const std::string str;
182 };
183
184 /// Array to map Command enum to associated info.
185 static const CommandInfo commandInfo[];
186
187 private:
188
189 Command cmd;
190
191 bool
192 testCmdAttrib(MemCmd::Attribute attrib) const
193 {
194 return commandInfo[cmd].attributes[attrib] != 0;
195 }
196
197 public:
198
199 bool isRead() const { return testCmdAttrib(IsRead); }
200 bool isWrite() const { return testCmdAttrib(IsWrite); }
201 bool isUpgrade() const { return testCmdAttrib(IsUpgrade); }
202 bool isRequest() const { return testCmdAttrib(IsRequest); }
203 bool isResponse() const { return testCmdAttrib(IsResponse); }
204 bool needsWritable() const { return testCmdAttrib(NeedsWritable); }
205 bool needsResponse() const { return testCmdAttrib(NeedsResponse); }
206 bool isInvalidate() const { return testCmdAttrib(IsInvalidate); }
207 bool isEviction() const { return testCmdAttrib(IsEviction); }
208 bool isClean() const { return testCmdAttrib(IsClean); }
209 bool fromCache() const { return testCmdAttrib(FromCache); }
210
211 /**
212 * A writeback is an eviction that carries data.
213 */
214 bool isWriteback() const { return testCmdAttrib(IsEviction) &&
215 testCmdAttrib(HasData); }
216
217 /**
218 * Check if this particular packet type carries payload data. Note
219 * that this does not reflect if the data pointer of the packet is
220 * valid or not.
221 */
222 bool hasData() const { return testCmdAttrib(HasData); }
223 bool isLLSC() const { return testCmdAttrib(IsLlsc); }
224 bool isSWPrefetch() const { return testCmdAttrib(IsSWPrefetch); }
225 bool isHWPrefetch() const { return testCmdAttrib(IsHWPrefetch); }
226 bool isPrefetch() const { return testCmdAttrib(IsSWPrefetch) ||
227 testCmdAttrib(IsHWPrefetch); }
228 bool isError() const { return testCmdAttrib(IsError); }
229 bool isPrint() const { return testCmdAttrib(IsPrint); }
230 bool isFlush() const { return testCmdAttrib(IsFlush); }
231
232 Command
233 responseCommand() const
234 {
235 return commandInfo[cmd].response;
236 }
237
238 /// Return the string to a cmd given by idx.
239 const std::string &toString() const { return commandInfo[cmd].str; }
240 int toInt() const { return (int)cmd; }
241
242 MemCmd(Command _cmd) : cmd(_cmd) { }
243 MemCmd(int _cmd) : cmd((Command)_cmd) { }
244 MemCmd() : cmd(InvalidCmd) { }
245
246 bool operator==(MemCmd c2) const { return (cmd == c2.cmd); }
247 bool operator!=(MemCmd c2) const { return (cmd != c2.cmd); }
248};
249
250/**
251 * A Packet is used to encapsulate a transfer between two objects in
252 * the memory system (e.g., the L1 and L2 cache). (In contrast, a
253 * single Request travels all the way from the requester to the
254 * ultimate destination and back, possibly being conveyed by several
255 * different Packets along the way.)
256 */
257class Packet : public Printable
258{
259 public:
260 typedef uint32_t FlagsType;
261 typedef ::Flags<FlagsType> Flags;
262
263 private:
264
265 enum : FlagsType {
266 // Flags to transfer across when copying a packet
267 COPY_FLAGS = 0x0000003F,
268
269 // Flags that are used to create reponse packets
270 RESPONDER_FLAGS = 0x00000009,
271
272 // Does this packet have sharers (which means it should not be
273 // considered writable) or not. See setHasSharers below.
274 HAS_SHARERS = 0x00000001,
275
276 // Special control flags
277 /// Special timing-mode atomic snoop for multi-level coherence.
278 EXPRESS_SNOOP = 0x00000002,
279
280 /// Allow a responding cache to inform the cache hierarchy
281 /// that it had a writable copy before responding. See
282 /// setResponderHadWritable below.
283 RESPONDER_HAD_WRITABLE = 0x00000004,
284
285 // Snoop co-ordination flag to indicate that a cache is
286 // responding to a snoop. See setCacheResponding below.
287 CACHE_RESPONDING = 0x00000008,
288
289 // The writeback/writeclean should be propagated further
290 // downstream by the receiver
291 WRITE_THROUGH = 0x00000010,
292
293 // Response co-ordination flag for cache maintenance
294 // operations
295 SATISFIED = 0x00000020,
296
297 /// Are the 'addr' and 'size' fields valid?
298 VALID_ADDR = 0x00000100,
299 VALID_SIZE = 0x00000200,
300
301 /// Is the data pointer set to a value that shouldn't be freed
302 /// when the packet is destroyed?
303 STATIC_DATA = 0x00001000,
304 /// The data pointer points to a value that should be freed when
305 /// the packet is destroyed. The pointer is assumed to be pointing
306 /// to an array, and delete [] is consequently called
307 DYNAMIC_DATA = 0x00002000,
308
309 /// suppress the error if this packet encounters a functional
310 /// access failure.
311 SUPPRESS_FUNC_ERROR = 0x00008000,
312
313 // Signal block present to squash prefetch and cache evict packets
314 // through express snoop flag
315 BLOCK_CACHED = 0x00010000
316 };
317
318 Flags flags;
319
320 public:
321 typedef MemCmd::Command Command;
322
323 /// The command field of the packet.
324 MemCmd cmd;
325
326 const PacketId id;
327
328 /// A pointer to the original request.
329 RequestPtr req;
330
331 private:
332 /**
333 * A pointer to the data being transferred. It can be different
334 * sizes at each level of the hierarchy so it belongs to the
335 * packet, not request. This may or may not be populated when a
336 * responder receives the packet. If not populated memory should
337 * be allocated.
338 */
339 PacketDataPtr data;
340
341 /// The address of the request. This address could be virtual or
342 /// physical, depending on the system configuration.
343 Addr addr;
344
345 /// True if the request targets the secure memory space.
346 bool _isSecure;
347
348 /// The size of the request or transfer.
349 unsigned size;
350
351 /**
352 * Track the bytes found that satisfy a functional read.
353 */
354 std::vector<bool> bytesValid;
355
356 // Quality of Service priority value
357 uint8_t _qosValue;
358
359 public:
360
361 /**
362 * The extra delay from seeing the packet until the header is
363 * transmitted. This delay is used to communicate the crossbar
364 * forwarding latency to the neighbouring object (e.g. a cache)
365 * that actually makes the packet wait. As the delay is relative,
366 * a 32-bit unsigned should be sufficient.
367 */
368 uint32_t headerDelay;
369
370 /**
371 * Keep track of the extra delay incurred by snooping upwards
372 * before sending a request down the memory system. This is used
373 * by the coherent crossbar to account for the additional request
374 * delay.
375 */
376 uint32_t snoopDelay;
377
378 /**
379 * The extra pipelining delay from seeing the packet until the end of
380 * payload is transmitted by the component that provided it (if
381 * any). This includes the header delay. Similar to the header
382 * delay, this is used to make up for the fact that the
383 * crossbar does not make the packet wait. As the delay is
384 * relative, a 32-bit unsigned should be sufficient.
385 */
386 uint32_t payloadDelay;
387
388 /**
389 * A virtual base opaque structure used to hold state associated
390 * with the packet (e.g., an MSHR), specific to a MemObject that
391 * sees the packet. A pointer to this state is returned in the
392 * packet's response so that the MemObject in question can quickly
393 * look up the state needed to process it. A specific subclass
394 * would be derived from this to carry state specific to a
395 * particular sending device.
396 *
397 * As multiple MemObjects may add their SenderState throughout the
398 * memory system, the SenderStates create a stack, where a
399 * MemObject can add a new Senderstate, as long as the
400 * predecessing SenderState is restored when the response comes
401 * back. For this reason, the predecessor should always be
402 * populated with the current SenderState of a packet before
403 * modifying the senderState field in the request packet.
404 */
405 struct SenderState
406 {
407 SenderState* predecessor;
408 SenderState() : predecessor(NULL) {}
409 virtual ~SenderState() {}
410 };
411
412 /**
413 * Object used to maintain state of a PrintReq. The senderState
414 * field of a PrintReq should always be of this type.
415 */
416 class PrintReqState : public SenderState
417 {
418 private:
419 /**
420 * An entry in the label stack.
421 */
422 struct LabelStackEntry
423 {
424 const std::string label;
425 std::string *prefix;
426 bool labelPrinted;
427 LabelStackEntry(const std::string &_label, std::string *_prefix);
428 };
429
430 typedef std::list<LabelStackEntry> LabelStack;
431 LabelStack labelStack;
432
433 std::string *curPrefixPtr;
434
435 public:
436 std::ostream &os;
437 const int verbosity;
438
439 PrintReqState(std::ostream &os, int verbosity = 0);
440 ~PrintReqState();
441
442 /**
443 * Returns the current line prefix.
444 */
445 const std::string &curPrefix() { return *curPrefixPtr; }
446
447 /**
448 * Push a label onto the label stack, and prepend the given
449 * prefix string onto the current prefix. Labels will only be
450 * printed if an object within the label's scope is printed.
451 */
452 void pushLabel(const std::string &lbl,
453 const std::string &prefix = " ");
454
455 /**
456 * Pop a label off the label stack.
457 */
458 void popLabel();
459
460 /**
461 * Print all of the pending unprinted labels on the
462 * stack. Called by printObj(), so normally not called by
463 * users unless bypassing printObj().
464 */
465 void printLabels();
466
467 /**
468 * Print a Printable object to os, because it matched the
469 * address on a PrintReq.
470 */
471 void printObj(Printable *obj);
472 };
473
474 /**
475 * This packet's sender state. Devices should use dynamic_cast<>
476 * to cast to the state appropriate to the sender. The intent of
477 * this variable is to allow a device to attach extra information
478 * to a request. A response packet must return the sender state
479 * that was attached to the original request (even if a new packet
480 * is created).
481 */
482 SenderState *senderState;
483
484 /**
485 * Push a new sender state to the packet and make the current
486 * sender state the predecessor of the new one. This should be
487 * prefered over direct manipulation of the senderState member
488 * variable.
489 *
490 * @param sender_state SenderState to push at the top of the stack
491 */
492 void pushSenderState(SenderState *sender_state);
493
494 /**
495 * Pop the top of the state stack and return a pointer to it. This
496 * assumes the current sender state is not NULL. This should be
497 * preferred over direct manipulation of the senderState member
498 * variable.
499 *
500 * @return The current top of the stack
501 */
502 SenderState *popSenderState();
503
504 /**
505 * Go through the sender state stack and return the first instance
506 * that is of type T (as determined by a dynamic_cast). If there
507 * is no sender state of type T, NULL is returned.
508 *
509 * @return The topmost state of type T
510 */
511 template <typename T>
512 T * findNextSenderState() const
513 {
514 T *t = NULL;
515 SenderState* sender_state = senderState;
516 while (t == NULL && sender_state != NULL) {
517 t = dynamic_cast<T*>(sender_state);
518 sender_state = sender_state->predecessor;
519 }
520 return t;
521 }
522
523 /// Return the string name of the cmd field (for debugging and
524 /// tracing).
525 const std::string &cmdString() const { return cmd.toString(); }
526
527 /// Return the index of this command.
528 inline int cmdToIndex() const { return cmd.toInt(); }
529
530 bool isRead() const { return cmd.isRead(); }
531 bool isWrite() const { return cmd.isWrite(); }
532 bool isUpgrade() const { return cmd.isUpgrade(); }
533 bool isRequest() const { return cmd.isRequest(); }
534 bool isResponse() const { return cmd.isResponse(); }
535 bool needsWritable() const
536 {
537 // we should never check if a response needsWritable, the
538 // request has this flag, and for a response we should rather
539 // look at the hasSharers flag (if not set, the response is to
540 // be considered writable)
541 assert(isRequest());
542 return cmd.needsWritable();
543 }
544 bool needsResponse() const { return cmd.needsResponse(); }
545 bool isInvalidate() const { return cmd.isInvalidate(); }
546 bool isEviction() const { return cmd.isEviction(); }
547 bool isClean() const { return cmd.isClean(); }
548 bool fromCache() const { return cmd.fromCache(); }
549 bool isWriteback() const { return cmd.isWriteback(); }
550 bool hasData() const { return cmd.hasData(); }
551 bool hasRespData() const
552 {
553 MemCmd resp_cmd = cmd.responseCommand();
554 return resp_cmd.hasData();
555 }
556 bool isLLSC() const { return cmd.isLLSC(); }
557 bool isError() const { return cmd.isError(); }
558 bool isPrint() const { return cmd.isPrint(); }
559 bool isFlush() const { return cmd.isFlush(); }
560
561 bool isWholeLineWrite(unsigned blk_size)
562 {
563 return (cmd == MemCmd::WriteReq || cmd == MemCmd::WriteLineReq) &&
564 getOffset(blk_size) == 0 && getSize() == blk_size;
565 }
566
567 //@{
568 /// Snoop flags
569 /**
570 * Set the cacheResponding flag. This is used by the caches to
571 * signal another cache that they are responding to a request. A
572 * cache will only respond to snoops if it has the line in either
573 * Modified or Owned state. Note that on snoop hits we always pass
574 * the line as Modified and never Owned. In the case of an Owned
575 * line we proceed to invalidate all other copies.
576 *
577 * On a cache fill (see Cache::handleFill), we check hasSharers
578 * first, ignoring the cacheResponding flag if hasSharers is set.
579 * A line is consequently allocated as:
580 *
581 * hasSharers cacheResponding state
582 * true false Shared
583 * true true Shared
584 * false false Exclusive
585 * false true Modified
586 */
587 void setCacheResponding()
588 {
589 assert(isRequest());
590 assert(!flags.isSet(CACHE_RESPONDING));
591 flags.set(CACHE_RESPONDING);
592 }
593 bool cacheResponding() const { return flags.isSet(CACHE_RESPONDING); }
594 /**
595 * On fills, the hasSharers flag is used by the caches in
596 * combination with the cacheResponding flag, as clarified
597 * above. If the hasSharers flag is not set, the packet is passing
598 * writable. Thus, a response from a memory passes the line as
599 * writable by default.
600 *
601 * The hasSharers flag is also used by upstream caches to inform a
602 * downstream cache that they have the block (by calling
603 * setHasSharers on snoop request packets that hit in upstream
604 * cachs tags or MSHRs). If the snoop packet has sharers, a
605 * downstream cache is prevented from passing a dirty line upwards
606 * if it was not explicitly asked for a writable copy. See
607 * Cache::satisfyCpuSideRequest.
608 *
609 * The hasSharers flag is also used on writebacks, in
610 * combination with the WritbackClean or WritebackDirty commands,
611 * to allocate the block downstream either as:
612 *
613 * command hasSharers state
614 * WritebackDirty false Modified
615 * WritebackDirty true Owned
616 * WritebackClean false Exclusive
617 * WritebackClean true Shared
618 */
619 void setHasSharers() { flags.set(HAS_SHARERS); }
620 bool hasSharers() const { return flags.isSet(HAS_SHARERS); }
621 //@}
622
623 /**
624 * The express snoop flag is used for two purposes. Firstly, it is
625 * used to bypass flow control for normal (non-snoop) requests
626 * going downstream in the memory system. In cases where a cache
627 * is responding to a snoop from another cache (it had a dirty
628 * line), but the line is not writable (and there are possibly
629 * other copies), the express snoop flag is set by the downstream
630 * cache to invalidate all other copies in zero time. Secondly,
631 * the express snoop flag is also set to be able to distinguish
632 * snoop packets that came from a downstream cache, rather than
633 * snoop packets from neighbouring caches.
634 */
635 void setExpressSnoop() { flags.set(EXPRESS_SNOOP); }
636 bool isExpressSnoop() const { return flags.isSet(EXPRESS_SNOOP); }
637
638 /**
639 * On responding to a snoop request (which only happens for
640 * Modified or Owned lines), make sure that we can transform an
641 * Owned response to a Modified one. If this flag is not set, the
642 * responding cache had the line in the Owned state, and there are
643 * possibly other Shared copies in the memory system. A downstream
644 * cache helps in orchestrating the invalidation of these copies
645 * by sending out the appropriate express snoops.
646 */
647 void setResponderHadWritable()
648 {
649 assert(cacheResponding());
650 assert(!responderHadWritable());
651 flags.set(RESPONDER_HAD_WRITABLE);
652 }
653 bool responderHadWritable() const
654 { return flags.isSet(RESPONDER_HAD_WRITABLE); }
655
656 /**
657 * Copy the reponse flags from an input packet to this packet. The
658 * reponse flags determine whether a responder has been found and
659 * the state at which the block will be at the destination.
660 *
661 * @pkt The packet that we will copy flags from
662 */
663 void copyResponderFlags(const PacketPtr pkt);
664
665 /**
666 * A writeback/writeclean cmd gets propagated further downstream
667 * by the receiver when the flag is set.
668 */
669 void setWriteThrough()
670 {
671 assert(cmd.isWrite() &&
672 (cmd.isEviction() || cmd == MemCmd::WriteClean));
673 flags.set(WRITE_THROUGH);
674 }
675 void clearWriteThrough() { flags.clear(WRITE_THROUGH); }
676 bool writeThrough() const { return flags.isSet(WRITE_THROUGH); }
677
678 /**
679 * Set when a request hits in a cache and the cache is not going
680 * to respond. This is used by the crossbar to coordinate
681 * responses for cache maintenance operations.
682 */
683 void setSatisfied()
684 {
685 assert(cmd.isClean());
686 assert(!flags.isSet(SATISFIED));
687 flags.set(SATISFIED);
688 }
689 bool satisfied() const { return flags.isSet(SATISFIED); }
690
691 void setSuppressFuncError() { flags.set(SUPPRESS_FUNC_ERROR); }
692 bool suppressFuncError() const { return flags.isSet(SUPPRESS_FUNC_ERROR); }
693 void setBlockCached() { flags.set(BLOCK_CACHED); }
694 bool isBlockCached() const { return flags.isSet(BLOCK_CACHED); }
695 void clearBlockCached() { flags.clear(BLOCK_CACHED); }
696
697 /**
698 * QoS Value getter
699 * Returns 0 if QoS value was never set (constructor default).
700 *
701 * @return QoS priority value of the packet
702 */
703 inline uint8_t qosValue() const { return _qosValue; }
704
705 /**
706 * QoS Value setter
707 * Interface for setting QoS priority value of the packet.
708 *
709 * @param qos_value QoS priority value
710 */
711 inline void qosValue(const uint8_t qos_value)
712 { _qosValue = qos_value; }
713
714 inline MasterID masterId() const { return req->masterId(); }
715
716 // Network error conditions... encapsulate them as methods since
717 // their encoding keeps changing (from result field to command
718 // field, etc.)
719 void
720 setBadAddress()
721 {
722 assert(isResponse());
723 cmd = MemCmd::BadAddressError;
724 }
725
726 void copyError(Packet *pkt) { assert(pkt->isError()); cmd = pkt->cmd; }
727
728 Addr getAddr() const { assert(flags.isSet(VALID_ADDR)); return addr; }
729 /**
730 * Update the address of this packet mid-transaction. This is used
731 * by the address mapper to change an already set address to a new
732 * one based on the system configuration. It is intended to remap
733 * an existing address, so it asserts that the current address is
734 * valid.
735 */
736 void setAddr(Addr _addr) { assert(flags.isSet(VALID_ADDR)); addr = _addr; }
737
738 unsigned getSize() const { assert(flags.isSet(VALID_SIZE)); return size; }
739
740 /**
741 * Get address range to which this packet belongs.
742 *
743 * @return Address range of this packet.
744 */
745 AddrRange getAddrRange() const;
746
747 Addr getOffset(unsigned int blk_size) const
748 {
749 return getAddr() & Addr(blk_size - 1);
750 }
751
752 Addr getBlockAddr(unsigned int blk_size) const
753 {
754 return getAddr() & ~(Addr(blk_size - 1));
755 }
756
757 bool isSecure() const
758 {
759 assert(flags.isSet(VALID_ADDR));
760 return _isSecure;
761 }
762
763 /**
764 * Accessor function to atomic op.
765 */
766 AtomicOpFunctor *getAtomicOp() const { return req->getAtomicOpFunctor(); }
767 bool isAtomicOp() const { return req->isAtomic(); }
768
769 /**
770 * It has been determined that the SC packet should successfully update
771 * memory. Therefore, convert this SC packet to a normal write.
772 */
773 void
774 convertScToWrite()
775 {
776 assert(isLLSC());
777 assert(isWrite());
778 cmd = MemCmd::WriteReq;
779 }
780
781 /**
782 * When ruby is in use, Ruby will monitor the cache line and the
783 * phys memory should treat LL ops as normal reads.
784 */
785 void
786 convertLlToRead()
787 {
788 assert(isLLSC());
789 assert(isRead());
790 cmd = MemCmd::ReadReq;
791 }
792
793 /**
794 * Constructor. Note that a Request object must be constructed
795 * first, but the Requests's physical address and size fields need
796 * not be valid. The command must be supplied.
797 */
798 Packet(const RequestPtr &_req, MemCmd _cmd)
799 : cmd(_cmd), id((PacketId)_req.get()), req(_req),
800 data(nullptr), addr(0), _isSecure(false), size(0),
801 _qosValue(0), headerDelay(0), snoopDelay(0),
802 payloadDelay(0), senderState(NULL)
803 {
804 if (req->hasPaddr()) {
805 addr = req->getPaddr();
806 flags.set(VALID_ADDR);
807 _isSecure = req->isSecure();
808 }
809 if (req->hasSize()) {
810 size = req->getSize();
811 flags.set(VALID_SIZE);
812 }
813 }
814
815 /**
816 * Alternate constructor if you are trying to create a packet with
817 * a request that is for a whole block, not the address from the
818 * req. this allows for overriding the size/addr of the req.
819 */
820 Packet(const RequestPtr &_req, MemCmd _cmd, int _blkSize, PacketId _id = 0)
821 : cmd(_cmd), id(_id ? _id : (PacketId)_req.get()), req(_req),
822 data(nullptr), addr(0), _isSecure(false),
823 _qosValue(0), headerDelay(0),
824 snoopDelay(0), payloadDelay(0), senderState(NULL)
825 {
826 if (req->hasPaddr()) {
827 addr = req->getPaddr() & ~(_blkSize - 1);
828 flags.set(VALID_ADDR);
829 _isSecure = req->isSecure();
830 }
831 size = _blkSize;
832 flags.set(VALID_SIZE);
833 }
834
835 /**
836 * Alternate constructor for copying a packet. Copy all fields
837 * *except* if the original packet's data was dynamic, don't copy
838 * that, as we can't guarantee that the new packet's lifetime is
839 * less than that of the original packet. In this case the new
840 * packet should allocate its own data.
841 */
842 Packet(const PacketPtr pkt, bool clear_flags, bool alloc_data)
843 : cmd(pkt->cmd), id(pkt->id), req(pkt->req),
844 data(nullptr),
845 addr(pkt->addr), _isSecure(pkt->_isSecure), size(pkt->size),
846 bytesValid(pkt->bytesValid),
847 _qosValue(pkt->qosValue()),
848 headerDelay(pkt->headerDelay),
849 snoopDelay(0),
850 payloadDelay(pkt->payloadDelay),
851 senderState(pkt->senderState)
852 {
853 if (!clear_flags)
854 flags.set(pkt->flags & COPY_FLAGS);
855
856 flags.set(pkt->flags & (VALID_ADDR|VALID_SIZE));
857
858 // should we allocate space for data, or not, the express
859 // snoops do not need to carry any data as they only serve to
860 // co-ordinate state changes
861 if (alloc_data) {
862 // even if asked to allocate data, if the original packet
863 // holds static data, then the sender will not be doing
864 // any memcpy on receiving the response, thus we simply
865 // carry the pointer forward
866 if (pkt->flags.isSet(STATIC_DATA)) {
867 data = pkt->data;
868 flags.set(STATIC_DATA);
869 } else {
870 allocate();
871 }
872 }
873 }
874
875 /**
876 * Generate the appropriate read MemCmd based on the Request flags.
877 */
878 static MemCmd
879 makeReadCmd(const RequestPtr &req)
880 {
881 if (req->isLLSC())
882 return MemCmd::LoadLockedReq;
883 else if (req->isPrefetchEx())
884 return MemCmd::SoftPFExReq;
885 else if (req->isPrefetch())
886 return MemCmd::SoftPFReq;
887 else
888 return MemCmd::ReadReq;
889 }
890
891 /**
892 * Generate the appropriate write MemCmd based on the Request flags.
893 */
894 static MemCmd
895 makeWriteCmd(const RequestPtr &req)
896 {
897 if (req->isLLSC())
898 return MemCmd::StoreCondReq;
899 else if (req->isSwap() || req->isAtomic())
900 return MemCmd::SwapReq;
901 else if (req->isCacheInvalidate()) {
902 return req->isCacheClean() ? MemCmd::CleanInvalidReq :
903 MemCmd::InvalidateReq;
904 } else if (req->isCacheClean()) {
905 return MemCmd::CleanSharedReq;
906 } else
907 return MemCmd::WriteReq;
908 }
909
910 /**
911 * Constructor-like methods that return Packets based on Request objects.
912 * Fine-tune the MemCmd type if it's not a vanilla read or write.
913 */
914 static PacketPtr
915 createRead(const RequestPtr &req)
916 {
917 return new Packet(req, makeReadCmd(req));
918 }
919
920 static PacketPtr
921 createWrite(const RequestPtr &req)
922 {
923 return new Packet(req, makeWriteCmd(req));
924 }
925
926 /**
927 * clean up packet variables
928 */
929 ~Packet()
930 {
931 deleteData();
932 }
933
934 /**
935 * Take a request packet and modify it in place to be suitable for
936 * returning as a response to that request.
937 */
938 void
939 makeResponse()
940 {
941 assert(needsResponse());
942 assert(isRequest());
943 cmd = cmd.responseCommand();
944
945 // responses are never express, even if the snoop that
946 // triggered them was
947 flags.clear(EXPRESS_SNOOP);
948 }
949
950 void
951 makeAtomicResponse()
952 {
953 makeResponse();
954 }
955
956 void
957 makeTimingResponse()
958 {
959 makeResponse();
960 }
961
962 void
963 setFunctionalResponseStatus(bool success)
964 {
965 if (!success) {
966 if (isWrite()) {
967 cmd = MemCmd::FunctionalWriteError;
968 } else {
969 cmd = MemCmd::FunctionalReadError;
970 }
971 }
972 }
973
974 void
975 setSize(unsigned size)
976 {
977 assert(!flags.isSet(VALID_SIZE));
978
979 this->size = size;
980 flags.set(VALID_SIZE);
981 }
982
| 1/*
2 * Copyright (c) 2012-2019 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/addr_range.hh"
61#include "base/cast.hh"
62#include "base/compiler.hh"
63#include "base/flags.hh"
64#include "base/logging.hh"
65#include "base/printable.hh"
66#include "base/types.hh"
67#include "config/the_isa.hh"
68#include "mem/request.hh"
69#include "sim/core.hh"
70
71class Packet;
72typedef Packet *PacketPtr;
73typedef uint8_t* PacketDataPtr;
74typedef std::list<PacketPtr> PacketList;
75typedef uint64_t PacketId;
76
77class MemCmd
78{
79 friend class Packet;
80
81 public:
82 /**
83 * List of all commands associated with a packet.
84 */
85 enum Command
86 {
87 InvalidCmd,
88 ReadReq,
89 ReadResp,
90 ReadRespWithInvalidate,
91 WriteReq,
92 WriteResp,
93 WritebackDirty,
94 WritebackClean,
95 WriteClean, // writes dirty data below without evicting
96 CleanEvict,
97 SoftPFReq,
98 SoftPFExReq,
99 HardPFReq,
100 SoftPFResp,
101 HardPFResp,
102 WriteLineReq,
103 UpgradeReq,
104 SCUpgradeReq, // Special "weak" upgrade for StoreCond
105 UpgradeResp,
106 SCUpgradeFailReq, // Failed SCUpgradeReq in MSHR (never sent)
107 UpgradeFailResp, // Valid for SCUpgradeReq only
108 ReadExReq,
109 ReadExResp,
110 ReadCleanReq,
111 ReadSharedReq,
112 LoadLockedReq,
113 StoreCondReq,
114 StoreCondFailReq, // Failed StoreCondReq in MSHR (never sent)
115 StoreCondResp,
116 SwapReq,
117 SwapResp,
118 MessageReq,
119 MessageResp,
120 MemFenceReq,
121 MemFenceResp,
122 CleanSharedReq,
123 CleanSharedResp,
124 CleanInvalidReq,
125 CleanInvalidResp,
126 // Error responses
127 // @TODO these should be classified as responses rather than
128 // requests; coding them as requests initially for backwards
129 // compatibility
130 InvalidDestError, // packet dest field invalid
131 BadAddressError, // memory address invalid
132 FunctionalReadError, // unable to fulfill functional read
133 FunctionalWriteError, // unable to fulfill functional write
134 // Fake simulator-only commands
135 PrintReq, // Print state matching address
136 FlushReq, //request for a cache flush
137 InvalidateReq, // request for address to be invalidated
138 InvalidateResp,
139 NUM_MEM_CMDS
140 };
141
142 private:
143 /**
144 * List of command attributes.
145 */
146 enum Attribute
147 {
148 IsRead, //!< Data flows from responder to requester
149 IsWrite, //!< Data flows from requester to responder
150 IsUpgrade,
151 IsInvalidate,
152 IsClean, //!< Cleans any existing dirty blocks
153 NeedsWritable, //!< Requires writable copy to complete in-cache
154 IsRequest, //!< Issued by requester
155 IsResponse, //!< Issue by responder
156 NeedsResponse, //!< Requester needs response from target
157 IsEviction,
158 IsSWPrefetch,
159 IsHWPrefetch,
160 IsLlsc, //!< Alpha/MIPS LL or SC access
161 HasData, //!< There is an associated payload
162 IsError, //!< Error response
163 IsPrint, //!< Print state matching address (for debugging)
164 IsFlush, //!< Flush the address from caches
165 FromCache, //!< Request originated from a caching agent
166 NUM_COMMAND_ATTRIBUTES
167 };
168
169 /**
170 * Structure that defines attributes and other data associated
171 * with a Command.
172 */
173 struct CommandInfo
174 {
175 /// Set of attribute flags.
176 const std::bitset<NUM_COMMAND_ATTRIBUTES> attributes;
177 /// Corresponding response for requests; InvalidCmd if no
178 /// response is applicable.
179 const Command response;
180 /// String representation (for printing)
181 const std::string str;
182 };
183
184 /// Array to map Command enum to associated info.
185 static const CommandInfo commandInfo[];
186
187 private:
188
189 Command cmd;
190
191 bool
192 testCmdAttrib(MemCmd::Attribute attrib) const
193 {
194 return commandInfo[cmd].attributes[attrib] != 0;
195 }
196
197 public:
198
199 bool isRead() const { return testCmdAttrib(IsRead); }
200 bool isWrite() const { return testCmdAttrib(IsWrite); }
201 bool isUpgrade() const { return testCmdAttrib(IsUpgrade); }
202 bool isRequest() const { return testCmdAttrib(IsRequest); }
203 bool isResponse() const { return testCmdAttrib(IsResponse); }
204 bool needsWritable() const { return testCmdAttrib(NeedsWritable); }
205 bool needsResponse() const { return testCmdAttrib(NeedsResponse); }
206 bool isInvalidate() const { return testCmdAttrib(IsInvalidate); }
207 bool isEviction() const { return testCmdAttrib(IsEviction); }
208 bool isClean() const { return testCmdAttrib(IsClean); }
209 bool fromCache() const { return testCmdAttrib(FromCache); }
210
211 /**
212 * A writeback is an eviction that carries data.
213 */
214 bool isWriteback() const { return testCmdAttrib(IsEviction) &&
215 testCmdAttrib(HasData); }
216
217 /**
218 * Check if this particular packet type carries payload data. Note
219 * that this does not reflect if the data pointer of the packet is
220 * valid or not.
221 */
222 bool hasData() const { return testCmdAttrib(HasData); }
223 bool isLLSC() const { return testCmdAttrib(IsLlsc); }
224 bool isSWPrefetch() const { return testCmdAttrib(IsSWPrefetch); }
225 bool isHWPrefetch() const { return testCmdAttrib(IsHWPrefetch); }
226 bool isPrefetch() const { return testCmdAttrib(IsSWPrefetch) ||
227 testCmdAttrib(IsHWPrefetch); }
228 bool isError() const { return testCmdAttrib(IsError); }
229 bool isPrint() const { return testCmdAttrib(IsPrint); }
230 bool isFlush() const { return testCmdAttrib(IsFlush); }
231
232 Command
233 responseCommand() const
234 {
235 return commandInfo[cmd].response;
236 }
237
238 /// Return the string to a cmd given by idx.
239 const std::string &toString() const { return commandInfo[cmd].str; }
240 int toInt() const { return (int)cmd; }
241
242 MemCmd(Command _cmd) : cmd(_cmd) { }
243 MemCmd(int _cmd) : cmd((Command)_cmd) { }
244 MemCmd() : cmd(InvalidCmd) { }
245
246 bool operator==(MemCmd c2) const { return (cmd == c2.cmd); }
247 bool operator!=(MemCmd c2) const { return (cmd != c2.cmd); }
248};
249
250/**
251 * A Packet is used to encapsulate a transfer between two objects in
252 * the memory system (e.g., the L1 and L2 cache). (In contrast, a
253 * single Request travels all the way from the requester to the
254 * ultimate destination and back, possibly being conveyed by several
255 * different Packets along the way.)
256 */
257class Packet : public Printable
258{
259 public:
260 typedef uint32_t FlagsType;
261 typedef ::Flags<FlagsType> Flags;
262
263 private:
264
265 enum : FlagsType {
266 // Flags to transfer across when copying a packet
267 COPY_FLAGS = 0x0000003F,
268
269 // Flags that are used to create reponse packets
270 RESPONDER_FLAGS = 0x00000009,
271
272 // Does this packet have sharers (which means it should not be
273 // considered writable) or not. See setHasSharers below.
274 HAS_SHARERS = 0x00000001,
275
276 // Special control flags
277 /// Special timing-mode atomic snoop for multi-level coherence.
278 EXPRESS_SNOOP = 0x00000002,
279
280 /// Allow a responding cache to inform the cache hierarchy
281 /// that it had a writable copy before responding. See
282 /// setResponderHadWritable below.
283 RESPONDER_HAD_WRITABLE = 0x00000004,
284
285 // Snoop co-ordination flag to indicate that a cache is
286 // responding to a snoop. See setCacheResponding below.
287 CACHE_RESPONDING = 0x00000008,
288
289 // The writeback/writeclean should be propagated further
290 // downstream by the receiver
291 WRITE_THROUGH = 0x00000010,
292
293 // Response co-ordination flag for cache maintenance
294 // operations
295 SATISFIED = 0x00000020,
296
297 /// Are the 'addr' and 'size' fields valid?
298 VALID_ADDR = 0x00000100,
299 VALID_SIZE = 0x00000200,
300
301 /// Is the data pointer set to a value that shouldn't be freed
302 /// when the packet is destroyed?
303 STATIC_DATA = 0x00001000,
304 /// The data pointer points to a value that should be freed when
305 /// the packet is destroyed. The pointer is assumed to be pointing
306 /// to an array, and delete [] is consequently called
307 DYNAMIC_DATA = 0x00002000,
308
309 /// suppress the error if this packet encounters a functional
310 /// access failure.
311 SUPPRESS_FUNC_ERROR = 0x00008000,
312
313 // Signal block present to squash prefetch and cache evict packets
314 // through express snoop flag
315 BLOCK_CACHED = 0x00010000
316 };
317
318 Flags flags;
319
320 public:
321 typedef MemCmd::Command Command;
322
323 /// The command field of the packet.
324 MemCmd cmd;
325
326 const PacketId id;
327
328 /// A pointer to the original request.
329 RequestPtr req;
330
331 private:
332 /**
333 * A pointer to the data being transferred. It can be different
334 * sizes at each level of the hierarchy so it belongs to the
335 * packet, not request. This may or may not be populated when a
336 * responder receives the packet. If not populated memory should
337 * be allocated.
338 */
339 PacketDataPtr data;
340
341 /// The address of the request. This address could be virtual or
342 /// physical, depending on the system configuration.
343 Addr addr;
344
345 /// True if the request targets the secure memory space.
346 bool _isSecure;
347
348 /// The size of the request or transfer.
349 unsigned size;
350
351 /**
352 * Track the bytes found that satisfy a functional read.
353 */
354 std::vector<bool> bytesValid;
355
356 // Quality of Service priority value
357 uint8_t _qosValue;
358
359 public:
360
361 /**
362 * The extra delay from seeing the packet until the header is
363 * transmitted. This delay is used to communicate the crossbar
364 * forwarding latency to the neighbouring object (e.g. a cache)
365 * that actually makes the packet wait. As the delay is relative,
366 * a 32-bit unsigned should be sufficient.
367 */
368 uint32_t headerDelay;
369
370 /**
371 * Keep track of the extra delay incurred by snooping upwards
372 * before sending a request down the memory system. This is used
373 * by the coherent crossbar to account for the additional request
374 * delay.
375 */
376 uint32_t snoopDelay;
377
378 /**
379 * The extra pipelining delay from seeing the packet until the end of
380 * payload is transmitted by the component that provided it (if
381 * any). This includes the header delay. Similar to the header
382 * delay, this is used to make up for the fact that the
383 * crossbar does not make the packet wait. As the delay is
384 * relative, a 32-bit unsigned should be sufficient.
385 */
386 uint32_t payloadDelay;
387
388 /**
389 * A virtual base opaque structure used to hold state associated
390 * with the packet (e.g., an MSHR), specific to a MemObject that
391 * sees the packet. A pointer to this state is returned in the
392 * packet's response so that the MemObject in question can quickly
393 * look up the state needed to process it. A specific subclass
394 * would be derived from this to carry state specific to a
395 * particular sending device.
396 *
397 * As multiple MemObjects may add their SenderState throughout the
398 * memory system, the SenderStates create a stack, where a
399 * MemObject can add a new Senderstate, as long as the
400 * predecessing SenderState is restored when the response comes
401 * back. For this reason, the predecessor should always be
402 * populated with the current SenderState of a packet before
403 * modifying the senderState field in the request packet.
404 */
405 struct SenderState
406 {
407 SenderState* predecessor;
408 SenderState() : predecessor(NULL) {}
409 virtual ~SenderState() {}
410 };
411
412 /**
413 * Object used to maintain state of a PrintReq. The senderState
414 * field of a PrintReq should always be of this type.
415 */
416 class PrintReqState : public SenderState
417 {
418 private:
419 /**
420 * An entry in the label stack.
421 */
422 struct LabelStackEntry
423 {
424 const std::string label;
425 std::string *prefix;
426 bool labelPrinted;
427 LabelStackEntry(const std::string &_label, std::string *_prefix);
428 };
429
430 typedef std::list<LabelStackEntry> LabelStack;
431 LabelStack labelStack;
432
433 std::string *curPrefixPtr;
434
435 public:
436 std::ostream &os;
437 const int verbosity;
438
439 PrintReqState(std::ostream &os, int verbosity = 0);
440 ~PrintReqState();
441
442 /**
443 * Returns the current line prefix.
444 */
445 const std::string &curPrefix() { return *curPrefixPtr; }
446
447 /**
448 * Push a label onto the label stack, and prepend the given
449 * prefix string onto the current prefix. Labels will only be
450 * printed if an object within the label's scope is printed.
451 */
452 void pushLabel(const std::string &lbl,
453 const std::string &prefix = " ");
454
455 /**
456 * Pop a label off the label stack.
457 */
458 void popLabel();
459
460 /**
461 * Print all of the pending unprinted labels on the
462 * stack. Called by printObj(), so normally not called by
463 * users unless bypassing printObj().
464 */
465 void printLabels();
466
467 /**
468 * Print a Printable object to os, because it matched the
469 * address on a PrintReq.
470 */
471 void printObj(Printable *obj);
472 };
473
474 /**
475 * This packet's sender state. Devices should use dynamic_cast<>
476 * to cast to the state appropriate to the sender. The intent of
477 * this variable is to allow a device to attach extra information
478 * to a request. A response packet must return the sender state
479 * that was attached to the original request (even if a new packet
480 * is created).
481 */
482 SenderState *senderState;
483
484 /**
485 * Push a new sender state to the packet and make the current
486 * sender state the predecessor of the new one. This should be
487 * prefered over direct manipulation of the senderState member
488 * variable.
489 *
490 * @param sender_state SenderState to push at the top of the stack
491 */
492 void pushSenderState(SenderState *sender_state);
493
494 /**
495 * Pop the top of the state stack and return a pointer to it. This
496 * assumes the current sender state is not NULL. This should be
497 * preferred over direct manipulation of the senderState member
498 * variable.
499 *
500 * @return The current top of the stack
501 */
502 SenderState *popSenderState();
503
504 /**
505 * Go through the sender state stack and return the first instance
506 * that is of type T (as determined by a dynamic_cast). If there
507 * is no sender state of type T, NULL is returned.
508 *
509 * @return The topmost state of type T
510 */
511 template <typename T>
512 T * findNextSenderState() const
513 {
514 T *t = NULL;
515 SenderState* sender_state = senderState;
516 while (t == NULL && sender_state != NULL) {
517 t = dynamic_cast<T*>(sender_state);
518 sender_state = sender_state->predecessor;
519 }
520 return t;
521 }
522
523 /// Return the string name of the cmd field (for debugging and
524 /// tracing).
525 const std::string &cmdString() const { return cmd.toString(); }
526
527 /// Return the index of this command.
528 inline int cmdToIndex() const { return cmd.toInt(); }
529
530 bool isRead() const { return cmd.isRead(); }
531 bool isWrite() const { return cmd.isWrite(); }
532 bool isUpgrade() const { return cmd.isUpgrade(); }
533 bool isRequest() const { return cmd.isRequest(); }
534 bool isResponse() const { return cmd.isResponse(); }
535 bool needsWritable() const
536 {
537 // we should never check if a response needsWritable, the
538 // request has this flag, and for a response we should rather
539 // look at the hasSharers flag (if not set, the response is to
540 // be considered writable)
541 assert(isRequest());
542 return cmd.needsWritable();
543 }
544 bool needsResponse() const { return cmd.needsResponse(); }
545 bool isInvalidate() const { return cmd.isInvalidate(); }
546 bool isEviction() const { return cmd.isEviction(); }
547 bool isClean() const { return cmd.isClean(); }
548 bool fromCache() const { return cmd.fromCache(); }
549 bool isWriteback() const { return cmd.isWriteback(); }
550 bool hasData() const { return cmd.hasData(); }
551 bool hasRespData() const
552 {
553 MemCmd resp_cmd = cmd.responseCommand();
554 return resp_cmd.hasData();
555 }
556 bool isLLSC() const { return cmd.isLLSC(); }
557 bool isError() const { return cmd.isError(); }
558 bool isPrint() const { return cmd.isPrint(); }
559 bool isFlush() const { return cmd.isFlush(); }
560
561 bool isWholeLineWrite(unsigned blk_size)
562 {
563 return (cmd == MemCmd::WriteReq || cmd == MemCmd::WriteLineReq) &&
564 getOffset(blk_size) == 0 && getSize() == blk_size;
565 }
566
567 //@{
568 /// Snoop flags
569 /**
570 * Set the cacheResponding flag. This is used by the caches to
571 * signal another cache that they are responding to a request. A
572 * cache will only respond to snoops if it has the line in either
573 * Modified or Owned state. Note that on snoop hits we always pass
574 * the line as Modified and never Owned. In the case of an Owned
575 * line we proceed to invalidate all other copies.
576 *
577 * On a cache fill (see Cache::handleFill), we check hasSharers
578 * first, ignoring the cacheResponding flag if hasSharers is set.
579 * A line is consequently allocated as:
580 *
581 * hasSharers cacheResponding state
582 * true false Shared
583 * true true Shared
584 * false false Exclusive
585 * false true Modified
586 */
587 void setCacheResponding()
588 {
589 assert(isRequest());
590 assert(!flags.isSet(CACHE_RESPONDING));
591 flags.set(CACHE_RESPONDING);
592 }
593 bool cacheResponding() const { return flags.isSet(CACHE_RESPONDING); }
594 /**
595 * On fills, the hasSharers flag is used by the caches in
596 * combination with the cacheResponding flag, as clarified
597 * above. If the hasSharers flag is not set, the packet is passing
598 * writable. Thus, a response from a memory passes the line as
599 * writable by default.
600 *
601 * The hasSharers flag is also used by upstream caches to inform a
602 * downstream cache that they have the block (by calling
603 * setHasSharers on snoop request packets that hit in upstream
604 * cachs tags or MSHRs). If the snoop packet has sharers, a
605 * downstream cache is prevented from passing a dirty line upwards
606 * if it was not explicitly asked for a writable copy. See
607 * Cache::satisfyCpuSideRequest.
608 *
609 * The hasSharers flag is also used on writebacks, in
610 * combination with the WritbackClean or WritebackDirty commands,
611 * to allocate the block downstream either as:
612 *
613 * command hasSharers state
614 * WritebackDirty false Modified
615 * WritebackDirty true Owned
616 * WritebackClean false Exclusive
617 * WritebackClean true Shared
618 */
619 void setHasSharers() { flags.set(HAS_SHARERS); }
620 bool hasSharers() const { return flags.isSet(HAS_SHARERS); }
621 //@}
622
623 /**
624 * The express snoop flag is used for two purposes. Firstly, it is
625 * used to bypass flow control for normal (non-snoop) requests
626 * going downstream in the memory system. In cases where a cache
627 * is responding to a snoop from another cache (it had a dirty
628 * line), but the line is not writable (and there are possibly
629 * other copies), the express snoop flag is set by the downstream
630 * cache to invalidate all other copies in zero time. Secondly,
631 * the express snoop flag is also set to be able to distinguish
632 * snoop packets that came from a downstream cache, rather than
633 * snoop packets from neighbouring caches.
634 */
635 void setExpressSnoop() { flags.set(EXPRESS_SNOOP); }
636 bool isExpressSnoop() const { return flags.isSet(EXPRESS_SNOOP); }
637
638 /**
639 * On responding to a snoop request (which only happens for
640 * Modified or Owned lines), make sure that we can transform an
641 * Owned response to a Modified one. If this flag is not set, the
642 * responding cache had the line in the Owned state, and there are
643 * possibly other Shared copies in the memory system. A downstream
644 * cache helps in orchestrating the invalidation of these copies
645 * by sending out the appropriate express snoops.
646 */
647 void setResponderHadWritable()
648 {
649 assert(cacheResponding());
650 assert(!responderHadWritable());
651 flags.set(RESPONDER_HAD_WRITABLE);
652 }
653 bool responderHadWritable() const
654 { return flags.isSet(RESPONDER_HAD_WRITABLE); }
655
656 /**
657 * Copy the reponse flags from an input packet to this packet. The
658 * reponse flags determine whether a responder has been found and
659 * the state at which the block will be at the destination.
660 *
661 * @pkt The packet that we will copy flags from
662 */
663 void copyResponderFlags(const PacketPtr pkt);
664
665 /**
666 * A writeback/writeclean cmd gets propagated further downstream
667 * by the receiver when the flag is set.
668 */
669 void setWriteThrough()
670 {
671 assert(cmd.isWrite() &&
672 (cmd.isEviction() || cmd == MemCmd::WriteClean));
673 flags.set(WRITE_THROUGH);
674 }
675 void clearWriteThrough() { flags.clear(WRITE_THROUGH); }
676 bool writeThrough() const { return flags.isSet(WRITE_THROUGH); }
677
678 /**
679 * Set when a request hits in a cache and the cache is not going
680 * to respond. This is used by the crossbar to coordinate
681 * responses for cache maintenance operations.
682 */
683 void setSatisfied()
684 {
685 assert(cmd.isClean());
686 assert(!flags.isSet(SATISFIED));
687 flags.set(SATISFIED);
688 }
689 bool satisfied() const { return flags.isSet(SATISFIED); }
690
691 void setSuppressFuncError() { flags.set(SUPPRESS_FUNC_ERROR); }
692 bool suppressFuncError() const { return flags.isSet(SUPPRESS_FUNC_ERROR); }
693 void setBlockCached() { flags.set(BLOCK_CACHED); }
694 bool isBlockCached() const { return flags.isSet(BLOCK_CACHED); }
695 void clearBlockCached() { flags.clear(BLOCK_CACHED); }
696
697 /**
698 * QoS Value getter
699 * Returns 0 if QoS value was never set (constructor default).
700 *
701 * @return QoS priority value of the packet
702 */
703 inline uint8_t qosValue() const { return _qosValue; }
704
705 /**
706 * QoS Value setter
707 * Interface for setting QoS priority value of the packet.
708 *
709 * @param qos_value QoS priority value
710 */
711 inline void qosValue(const uint8_t qos_value)
712 { _qosValue = qos_value; }
713
714 inline MasterID masterId() const { return req->masterId(); }
715
716 // Network error conditions... encapsulate them as methods since
717 // their encoding keeps changing (from result field to command
718 // field, etc.)
719 void
720 setBadAddress()
721 {
722 assert(isResponse());
723 cmd = MemCmd::BadAddressError;
724 }
725
726 void copyError(Packet *pkt) { assert(pkt->isError()); cmd = pkt->cmd; }
727
728 Addr getAddr() const { assert(flags.isSet(VALID_ADDR)); return addr; }
729 /**
730 * Update the address of this packet mid-transaction. This is used
731 * by the address mapper to change an already set address to a new
732 * one based on the system configuration. It is intended to remap
733 * an existing address, so it asserts that the current address is
734 * valid.
735 */
736 void setAddr(Addr _addr) { assert(flags.isSet(VALID_ADDR)); addr = _addr; }
737
738 unsigned getSize() const { assert(flags.isSet(VALID_SIZE)); return size; }
739
740 /**
741 * Get address range to which this packet belongs.
742 *
743 * @return Address range of this packet.
744 */
745 AddrRange getAddrRange() const;
746
747 Addr getOffset(unsigned int blk_size) const
748 {
749 return getAddr() & Addr(blk_size - 1);
750 }
751
752 Addr getBlockAddr(unsigned int blk_size) const
753 {
754 return getAddr() & ~(Addr(blk_size - 1));
755 }
756
757 bool isSecure() const
758 {
759 assert(flags.isSet(VALID_ADDR));
760 return _isSecure;
761 }
762
763 /**
764 * Accessor function to atomic op.
765 */
766 AtomicOpFunctor *getAtomicOp() const { return req->getAtomicOpFunctor(); }
767 bool isAtomicOp() const { return req->isAtomic(); }
768
769 /**
770 * It has been determined that the SC packet should successfully update
771 * memory. Therefore, convert this SC packet to a normal write.
772 */
773 void
774 convertScToWrite()
775 {
776 assert(isLLSC());
777 assert(isWrite());
778 cmd = MemCmd::WriteReq;
779 }
780
781 /**
782 * When ruby is in use, Ruby will monitor the cache line and the
783 * phys memory should treat LL ops as normal reads.
784 */
785 void
786 convertLlToRead()
787 {
788 assert(isLLSC());
789 assert(isRead());
790 cmd = MemCmd::ReadReq;
791 }
792
793 /**
794 * Constructor. Note that a Request object must be constructed
795 * first, but the Requests's physical address and size fields need
796 * not be valid. The command must be supplied.
797 */
798 Packet(const RequestPtr &_req, MemCmd _cmd)
799 : cmd(_cmd), id((PacketId)_req.get()), req(_req),
800 data(nullptr), addr(0), _isSecure(false), size(0),
801 _qosValue(0), headerDelay(0), snoopDelay(0),
802 payloadDelay(0), senderState(NULL)
803 {
804 if (req->hasPaddr()) {
805 addr = req->getPaddr();
806 flags.set(VALID_ADDR);
807 _isSecure = req->isSecure();
808 }
809 if (req->hasSize()) {
810 size = req->getSize();
811 flags.set(VALID_SIZE);
812 }
813 }
814
815 /**
816 * Alternate constructor if you are trying to create a packet with
817 * a request that is for a whole block, not the address from the
818 * req. this allows for overriding the size/addr of the req.
819 */
820 Packet(const RequestPtr &_req, MemCmd _cmd, int _blkSize, PacketId _id = 0)
821 : cmd(_cmd), id(_id ? _id : (PacketId)_req.get()), req(_req),
822 data(nullptr), addr(0), _isSecure(false),
823 _qosValue(0), headerDelay(0),
824 snoopDelay(0), payloadDelay(0), senderState(NULL)
825 {
826 if (req->hasPaddr()) {
827 addr = req->getPaddr() & ~(_blkSize - 1);
828 flags.set(VALID_ADDR);
829 _isSecure = req->isSecure();
830 }
831 size = _blkSize;
832 flags.set(VALID_SIZE);
833 }
834
835 /**
836 * Alternate constructor for copying a packet. Copy all fields
837 * *except* if the original packet's data was dynamic, don't copy
838 * that, as we can't guarantee that the new packet's lifetime is
839 * less than that of the original packet. In this case the new
840 * packet should allocate its own data.
841 */
842 Packet(const PacketPtr pkt, bool clear_flags, bool alloc_data)
843 : cmd(pkt->cmd), id(pkt->id), req(pkt->req),
844 data(nullptr),
845 addr(pkt->addr), _isSecure(pkt->_isSecure), size(pkt->size),
846 bytesValid(pkt->bytesValid),
847 _qosValue(pkt->qosValue()),
848 headerDelay(pkt->headerDelay),
849 snoopDelay(0),
850 payloadDelay(pkt->payloadDelay),
851 senderState(pkt->senderState)
852 {
853 if (!clear_flags)
854 flags.set(pkt->flags & COPY_FLAGS);
855
856 flags.set(pkt->flags & (VALID_ADDR|VALID_SIZE));
857
858 // should we allocate space for data, or not, the express
859 // snoops do not need to carry any data as they only serve to
860 // co-ordinate state changes
861 if (alloc_data) {
862 // even if asked to allocate data, if the original packet
863 // holds static data, then the sender will not be doing
864 // any memcpy on receiving the response, thus we simply
865 // carry the pointer forward
866 if (pkt->flags.isSet(STATIC_DATA)) {
867 data = pkt->data;
868 flags.set(STATIC_DATA);
869 } else {
870 allocate();
871 }
872 }
873 }
874
875 /**
876 * Generate the appropriate read MemCmd based on the Request flags.
877 */
878 static MemCmd
879 makeReadCmd(const RequestPtr &req)
880 {
881 if (req->isLLSC())
882 return MemCmd::LoadLockedReq;
883 else if (req->isPrefetchEx())
884 return MemCmd::SoftPFExReq;
885 else if (req->isPrefetch())
886 return MemCmd::SoftPFReq;
887 else
888 return MemCmd::ReadReq;
889 }
890
891 /**
892 * Generate the appropriate write MemCmd based on the Request flags.
893 */
894 static MemCmd
895 makeWriteCmd(const RequestPtr &req)
896 {
897 if (req->isLLSC())
898 return MemCmd::StoreCondReq;
899 else if (req->isSwap() || req->isAtomic())
900 return MemCmd::SwapReq;
901 else if (req->isCacheInvalidate()) {
902 return req->isCacheClean() ? MemCmd::CleanInvalidReq :
903 MemCmd::InvalidateReq;
904 } else if (req->isCacheClean()) {
905 return MemCmd::CleanSharedReq;
906 } else
907 return MemCmd::WriteReq;
908 }
909
910 /**
911 * Constructor-like methods that return Packets based on Request objects.
912 * Fine-tune the MemCmd type if it's not a vanilla read or write.
913 */
914 static PacketPtr
915 createRead(const RequestPtr &req)
916 {
917 return new Packet(req, makeReadCmd(req));
918 }
919
920 static PacketPtr
921 createWrite(const RequestPtr &req)
922 {
923 return new Packet(req, makeWriteCmd(req));
924 }
925
926 /**
927 * clean up packet variables
928 */
929 ~Packet()
930 {
931 deleteData();
932 }
933
934 /**
935 * Take a request packet and modify it in place to be suitable for
936 * returning as a response to that request.
937 */
938 void
939 makeResponse()
940 {
941 assert(needsResponse());
942 assert(isRequest());
943 cmd = cmd.responseCommand();
944
945 // responses are never express, even if the snoop that
946 // triggered them was
947 flags.clear(EXPRESS_SNOOP);
948 }
949
950 void
951 makeAtomicResponse()
952 {
953 makeResponse();
954 }
955
956 void
957 makeTimingResponse()
958 {
959 makeResponse();
960 }
961
962 void
963 setFunctionalResponseStatus(bool success)
964 {
965 if (!success) {
966 if (isWrite()) {
967 cmd = MemCmd::FunctionalWriteError;
968 } else {
969 cmd = MemCmd::FunctionalReadError;
970 }
971 }
972 }
973
974 void
975 setSize(unsigned size)
976 {
977 assert(!flags.isSet(VALID_SIZE));
978
979 this->size = size;
980 flags.set(VALID_SIZE);
981 }
982
|
984 public:
985 /**
986 * @{
987 * @name Data accessor mehtods
988 */
989
990 /**
991 * Set the data pointer to the following value that should not be
992 * freed. Static data allows us to do a single memcpy even if
993 * multiple packets are required to get from source to destination
994 * and back. In essence the pointer is set calling dataStatic on
995 * the original packet, and whenever this packet is copied and
996 * forwarded the same pointer is passed on. When a packet
997 * eventually reaches the destination holding the data, it is
998 * copied once into the location originally set. On the way back
999 * to the source, no copies are necessary.
1000 */
1001 template <typename T>
1002 void
1003 dataStatic(T *p)
1004 {
1005 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
1006 data = (PacketDataPtr)p;
1007 flags.set(STATIC_DATA);
1008 }
1009
1010 /**
1011 * Set the data pointer to the following value that should not be
1012 * freed. This version of the function allows the pointer passed
1013 * to us to be const. To avoid issues down the line we cast the
1014 * constness away, the alternative would be to keep both a const
1015 * and non-const data pointer and cleverly choose between
1016 * them. Note that this is only allowed for static data.
1017 */
1018 template <typename T>
1019 void
1020 dataStaticConst(const T *p)
1021 {
1022 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
1023 data = const_cast<PacketDataPtr>(p);
1024 flags.set(STATIC_DATA);
1025 }
1026
1027 /**
1028 * Set the data pointer to a value that should have delete []
1029 * called on it. Dynamic data is local to this packet, and as the
1030 * packet travels from source to destination, forwarded packets
1031 * will allocate their own data. When a packet reaches the final
1032 * destination it will populate the dynamic data of that specific
1033 * packet, and on the way back towards the source, memcpy will be
1034 * invoked in every step where a new packet was created e.g. in
1035 * the caches. Ultimately when the response reaches the source a
1036 * final memcpy is needed to extract the data from the packet
1037 * before it is deallocated.
1038 */
1039 template <typename T>
1040 void
1041 dataDynamic(T *p)
1042 {
1043 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
1044 data = (PacketDataPtr)p;
1045 flags.set(DYNAMIC_DATA);
1046 }
1047
1048 /**
1049 * get a pointer to the data ptr.
1050 */
1051 template <typename T>
1052 T*
1053 getPtr()
1054 {
1055 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
1056 return (T*)data;
1057 }
1058
1059 template <typename T>
1060 const T*
1061 getConstPtr() const
1062 {
1063 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
1064 return (const T*)data;
1065 }
1066
1067 /**
1068 * Get the data in the packet byte swapped from big endian to
1069 * host endian.
1070 */
1071 template <typename T>
1072 T getBE() const;
1073
1074 /**
1075 * Get the data in the packet byte swapped from little endian to
1076 * host endian.
1077 */
1078 template <typename T>
1079 T getLE() const;
1080
1081 /**
1082 * Get the data in the packet byte swapped from the specified
1083 * endianness.
1084 */
1085 template <typename T>
1086 T get(ByteOrder endian) const;
1087
1088#if THE_ISA != NULL_ISA
1089 /**
1090 * Get the data in the packet byte swapped from guest to host
1091 * endian.
1092 */
1093 template <typename T>
1094 T get() const
1095 M5_DEPRECATED_MSG("The memory system should be ISA independent.");
1096#endif
1097
1098 /** Set the value in the data pointer to v as big endian. */
1099 template <typename T>
1100 void setBE(T v);
1101
1102 /** Set the value in the data pointer to v as little endian. */
1103 template <typename T>
1104 void setLE(T v);
1105
1106 /**
1107 * Set the value in the data pointer to v using the specified
1108 * endianness.
1109 */
1110 template <typename T>
1111 void set(T v, ByteOrder endian);
1112
1113#if THE_ISA != NULL_ISA
1114 /** Set the value in the data pointer to v as guest endian. */
1115 template <typename T>
1116 void set(T v)
1117 M5_DEPRECATED_MSG("The memory system should be ISA independent.");
1118#endif
1119
1120 /**
1121 * Get the data in the packet byte swapped from the specified
1122 * endianness and zero-extended to 64 bits.
1123 */
1124 uint64_t getUintX(ByteOrder endian) const;
1125
1126 /**
1127 * Set the value in the word w after truncating it to the length
1128 * of the packet and then byteswapping it to the desired
1129 * endianness.
1130 */
1131 void setUintX(uint64_t w, ByteOrder endian);
1132
1133 /**
1134 * Copy data into the packet from the provided pointer.
1135 */
1136 void
1137 setData(const uint8_t *p)
1138 {
1139 // we should never be copying data onto itself, which means we
1140 // must idenfity packets with static data, as they carry the
1141 // same pointer from source to destination and back
1142 assert(p != getPtr<uint8_t>() || flags.isSet(STATIC_DATA));
1143
1144 if (p != getPtr<uint8_t>())
1145 // for packet with allocated dynamic data, we copy data from
1146 // one to the other, e.g. a forwarded response to a response
1147 std::memcpy(getPtr<uint8_t>(), p, getSize());
1148 }
1149
1150 /**
1151 * Copy data into the packet from the provided block pointer,
1152 * which is aligned to the given block size.
1153 */
1154 void
1155 setDataFromBlock(const uint8_t *blk_data, int blkSize)
1156 {
1157 setData(blk_data + getOffset(blkSize));
1158 }
1159
1160 /**
1161 * Copy data from the packet to the memory at the provided pointer.
1162 * @param p Pointer to which data will be copied.
1163 */
1164 void
1165 writeData(uint8_t *p) const
1166 {
1167 std::memcpy(p, getConstPtr<uint8_t>(), getSize());
1168 }
1169
1170 /**
1171 * Copy data from the packet to the provided block pointer, which
1172 * is aligned to the given block size.
1173 * @param blk_data Pointer to block to which data will be copied.
1174 * @param blkSize Block size in bytes.
1175 */
1176 void
1177 writeDataToBlock(uint8_t *blk_data, int blkSize) const
1178 {
1179 writeData(blk_data + getOffset(blkSize));
1180 }
1181
1182 /**
1183 * delete the data pointed to in the data pointer. Ok to call to
1184 * matter how data was allocted.
1185 */
1186 void
1187 deleteData()
1188 {
1189 if (flags.isSet(DYNAMIC_DATA))
1190 delete [] data;
1191
1192 flags.clear(STATIC_DATA|DYNAMIC_DATA);
1193 data = NULL;
1194 }
1195
1196 /** Allocate memory for the packet. */
1197 void
1198 allocate()
1199 {
1200 // if either this command or the response command has a data
1201 // payload, actually allocate space
1202 if (hasData() || hasRespData()) {
1203 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
1204 flags.set(DYNAMIC_DATA);
1205 data = new uint8_t[getSize()];
1206 }
1207 }
1208
1209 /** @} */
1210
1211 /** Get the data in the packet without byte swapping. */
1212 template <typename T>
1213 T getRaw() const;
1214
1215 /** Set the value in the data pointer to v without byte swapping. */
1216 template <typename T>
1217 void setRaw(T v);
1218
1219 public:
1220 /**
1221 * Check a functional request against a memory value stored in
1222 * another packet (i.e. an in-transit request or
1223 * response). Returns true if the current packet is a read, and
1224 * the other packet provides the data, which is then copied to the
1225 * current packet. If the current packet is a write, and the other
1226 * packet intersects this one, then we update the data
1227 * accordingly.
1228 */
1229 bool
1230 trySatisfyFunctional(PacketPtr other)
1231 {
1232 // all packets that are carrying a payload should have a valid
1233 // data pointer
1234 return trySatisfyFunctional(other, other->getAddr(), other->isSecure(),
1235 other->getSize(),
1236 other->hasData() ?
1237 other->getPtr<uint8_t>() : NULL);
1238 }
1239
1240 /**
1241 * Does the request need to check for cached copies of the same block
1242 * in the memory hierarchy above.
1243 **/
1244 bool
1245 mustCheckAbove() const
1246 {
1247 return cmd == MemCmd::HardPFReq || isEviction();
1248 }
1249
1250 /**
1251 * Is this packet a clean eviction, including both actual clean
1252 * evict packets, but also clean writebacks.
1253 */
1254 bool
1255 isCleanEviction() const
1256 {
1257 return cmd == MemCmd::CleanEvict || cmd == MemCmd::WritebackClean;
1258 }
1259
1260 /**
1261 * Check a functional request against a memory value represented
1262 * by a base/size pair and an associated data array. If the
1263 * current packet is a read, it may be satisfied by the memory
1264 * value. If the current packet is a write, it may update the
1265 * memory value.
1266 */
1267 bool
1268 trySatisfyFunctional(Printable *obj, Addr base, bool is_secure, int size,
1269 uint8_t *_data);
1270
1271 /**
1272 * Push label for PrintReq (safe to call unconditionally).
1273 */
1274 void
1275 pushLabel(const std::string &lbl)
1276 {
1277 if (isPrint())
1278 safe_cast<PrintReqState*>(senderState)->pushLabel(lbl);
1279 }
1280
1281 /**
1282 * Pop label for PrintReq (safe to call unconditionally).
1283 */
1284 void
1285 popLabel()
1286 {
1287 if (isPrint())
1288 safe_cast<PrintReqState*>(senderState)->popLabel();
1289 }
1290
1291 void print(std::ostream &o, int verbosity = 0,
1292 const std::string &prefix = "") const;
1293
1294 /**
1295 * A no-args wrapper of print(std::ostream...)
1296 * meant to be invoked from DPRINTFs
1297 * avoiding string overheads in fast mode
1298 * @return string with the request's type and start<->end addresses
1299 */
1300 std::string print() const;
1301};
1302
1303#endif //__MEM_PACKET_HH
| 1023 public:
1024 /**
1025 * @{
1026 * @name Data accessor mehtods
1027 */
1028
1029 /**
1030 * Set the data pointer to the following value that should not be
1031 * freed. Static data allows us to do a single memcpy even if
1032 * multiple packets are required to get from source to destination
1033 * and back. In essence the pointer is set calling dataStatic on
1034 * the original packet, and whenever this packet is copied and
1035 * forwarded the same pointer is passed on. When a packet
1036 * eventually reaches the destination holding the data, it is
1037 * copied once into the location originally set. On the way back
1038 * to the source, no copies are necessary.
1039 */
1040 template <typename T>
1041 void
1042 dataStatic(T *p)
1043 {
1044 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
1045 data = (PacketDataPtr)p;
1046 flags.set(STATIC_DATA);
1047 }
1048
1049 /**
1050 * Set the data pointer to the following value that should not be
1051 * freed. This version of the function allows the pointer passed
1052 * to us to be const. To avoid issues down the line we cast the
1053 * constness away, the alternative would be to keep both a const
1054 * and non-const data pointer and cleverly choose between
1055 * them. Note that this is only allowed for static data.
1056 */
1057 template <typename T>
1058 void
1059 dataStaticConst(const T *p)
1060 {
1061 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
1062 data = const_cast<PacketDataPtr>(p);
1063 flags.set(STATIC_DATA);
1064 }
1065
1066 /**
1067 * Set the data pointer to a value that should have delete []
1068 * called on it. Dynamic data is local to this packet, and as the
1069 * packet travels from source to destination, forwarded packets
1070 * will allocate their own data. When a packet reaches the final
1071 * destination it will populate the dynamic data of that specific
1072 * packet, and on the way back towards the source, memcpy will be
1073 * invoked in every step where a new packet was created e.g. in
1074 * the caches. Ultimately when the response reaches the source a
1075 * final memcpy is needed to extract the data from the packet
1076 * before it is deallocated.
1077 */
1078 template <typename T>
1079 void
1080 dataDynamic(T *p)
1081 {
1082 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
1083 data = (PacketDataPtr)p;
1084 flags.set(DYNAMIC_DATA);
1085 }
1086
1087 /**
1088 * get a pointer to the data ptr.
1089 */
1090 template <typename T>
1091 T*
1092 getPtr()
1093 {
1094 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
1095 return (T*)data;
1096 }
1097
1098 template <typename T>
1099 const T*
1100 getConstPtr() const
1101 {
1102 assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
1103 return (const T*)data;
1104 }
1105
1106 /**
1107 * Get the data in the packet byte swapped from big endian to
1108 * host endian.
1109 */
1110 template <typename T>
1111 T getBE() const;
1112
1113 /**
1114 * Get the data in the packet byte swapped from little endian to
1115 * host endian.
1116 */
1117 template <typename T>
1118 T getLE() const;
1119
1120 /**
1121 * Get the data in the packet byte swapped from the specified
1122 * endianness.
1123 */
1124 template <typename T>
1125 T get(ByteOrder endian) const;
1126
1127#if THE_ISA != NULL_ISA
1128 /**
1129 * Get the data in the packet byte swapped from guest to host
1130 * endian.
1131 */
1132 template <typename T>
1133 T get() const
1134 M5_DEPRECATED_MSG("The memory system should be ISA independent.");
1135#endif
1136
1137 /** Set the value in the data pointer to v as big endian. */
1138 template <typename T>
1139 void setBE(T v);
1140
1141 /** Set the value in the data pointer to v as little endian. */
1142 template <typename T>
1143 void setLE(T v);
1144
1145 /**
1146 * Set the value in the data pointer to v using the specified
1147 * endianness.
1148 */
1149 template <typename T>
1150 void set(T v, ByteOrder endian);
1151
1152#if THE_ISA != NULL_ISA
1153 /** Set the value in the data pointer to v as guest endian. */
1154 template <typename T>
1155 void set(T v)
1156 M5_DEPRECATED_MSG("The memory system should be ISA independent.");
1157#endif
1158
1159 /**
1160 * Get the data in the packet byte swapped from the specified
1161 * endianness and zero-extended to 64 bits.
1162 */
1163 uint64_t getUintX(ByteOrder endian) const;
1164
1165 /**
1166 * Set the value in the word w after truncating it to the length
1167 * of the packet and then byteswapping it to the desired
1168 * endianness.
1169 */
1170 void setUintX(uint64_t w, ByteOrder endian);
1171
1172 /**
1173 * Copy data into the packet from the provided pointer.
1174 */
1175 void
1176 setData(const uint8_t *p)
1177 {
1178 // we should never be copying data onto itself, which means we
1179 // must idenfity packets with static data, as they carry the
1180 // same pointer from source to destination and back
1181 assert(p != getPtr<uint8_t>() || flags.isSet(STATIC_DATA));
1182
1183 if (p != getPtr<uint8_t>())
1184 // for packet with allocated dynamic data, we copy data from
1185 // one to the other, e.g. a forwarded response to a response
1186 std::memcpy(getPtr<uint8_t>(), p, getSize());
1187 }
1188
1189 /**
1190 * Copy data into the packet from the provided block pointer,
1191 * which is aligned to the given block size.
1192 */
1193 void
1194 setDataFromBlock(const uint8_t *blk_data, int blkSize)
1195 {
1196 setData(blk_data + getOffset(blkSize));
1197 }
1198
1199 /**
1200 * Copy data from the packet to the memory at the provided pointer.
1201 * @param p Pointer to which data will be copied.
1202 */
1203 void
1204 writeData(uint8_t *p) const
1205 {
1206 std::memcpy(p, getConstPtr<uint8_t>(), getSize());
1207 }
1208
1209 /**
1210 * Copy data from the packet to the provided block pointer, which
1211 * is aligned to the given block size.
1212 * @param blk_data Pointer to block to which data will be copied.
1213 * @param blkSize Block size in bytes.
1214 */
1215 void
1216 writeDataToBlock(uint8_t *blk_data, int blkSize) const
1217 {
1218 writeData(blk_data + getOffset(blkSize));
1219 }
1220
1221 /**
1222 * delete the data pointed to in the data pointer. Ok to call to
1223 * matter how data was allocted.
1224 */
1225 void
1226 deleteData()
1227 {
1228 if (flags.isSet(DYNAMIC_DATA))
1229 delete [] data;
1230
1231 flags.clear(STATIC_DATA|DYNAMIC_DATA);
1232 data = NULL;
1233 }
1234
1235 /** Allocate memory for the packet. */
1236 void
1237 allocate()
1238 {
1239 // if either this command or the response command has a data
1240 // payload, actually allocate space
1241 if (hasData() || hasRespData()) {
1242 assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
1243 flags.set(DYNAMIC_DATA);
1244 data = new uint8_t[getSize()];
1245 }
1246 }
1247
1248 /** @} */
1249
1250 /** Get the data in the packet without byte swapping. */
1251 template <typename T>
1252 T getRaw() const;
1253
1254 /** Set the value in the data pointer to v without byte swapping. */
1255 template <typename T>
1256 void setRaw(T v);
1257
1258 public:
1259 /**
1260 * Check a functional request against a memory value stored in
1261 * another packet (i.e. an in-transit request or
1262 * response). Returns true if the current packet is a read, and
1263 * the other packet provides the data, which is then copied to the
1264 * current packet. If the current packet is a write, and the other
1265 * packet intersects this one, then we update the data
1266 * accordingly.
1267 */
1268 bool
1269 trySatisfyFunctional(PacketPtr other)
1270 {
1271 // all packets that are carrying a payload should have a valid
1272 // data pointer
1273 return trySatisfyFunctional(other, other->getAddr(), other->isSecure(),
1274 other->getSize(),
1275 other->hasData() ?
1276 other->getPtr<uint8_t>() : NULL);
1277 }
1278
1279 /**
1280 * Does the request need to check for cached copies of the same block
1281 * in the memory hierarchy above.
1282 **/
1283 bool
1284 mustCheckAbove() const
1285 {
1286 return cmd == MemCmd::HardPFReq || isEviction();
1287 }
1288
1289 /**
1290 * Is this packet a clean eviction, including both actual clean
1291 * evict packets, but also clean writebacks.
1292 */
1293 bool
1294 isCleanEviction() const
1295 {
1296 return cmd == MemCmd::CleanEvict || cmd == MemCmd::WritebackClean;
1297 }
1298
1299 /**
1300 * Check a functional request against a memory value represented
1301 * by a base/size pair and an associated data array. If the
1302 * current packet is a read, it may be satisfied by the memory
1303 * value. If the current packet is a write, it may update the
1304 * memory value.
1305 */
1306 bool
1307 trySatisfyFunctional(Printable *obj, Addr base, bool is_secure, int size,
1308 uint8_t *_data);
1309
1310 /**
1311 * Push label for PrintReq (safe to call unconditionally).
1312 */
1313 void
1314 pushLabel(const std::string &lbl)
1315 {
1316 if (isPrint())
1317 safe_cast<PrintReqState*>(senderState)->pushLabel(lbl);
1318 }
1319
1320 /**
1321 * Pop label for PrintReq (safe to call unconditionally).
1322 */
1323 void
1324 popLabel()
1325 {
1326 if (isPrint())
1327 safe_cast<PrintReqState*>(senderState)->popLabel();
1328 }
1329
1330 void print(std::ostream &o, int verbosity = 0,
1331 const std::string &prefix = "") const;
1332
1333 /**
1334 * A no-args wrapper of print(std::ostream...)
1335 * meant to be invoked from DPRINTFs
1336 * avoiding string overheads in fast mode
1337 * @return string with the request's type and start<->end addresses
1338 */
1339 std::string print() const;
1340};
1341
1342#endif //__MEM_PACKET_HH
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