packet.hh revision 3348
112837Sgabeblack@google.com/* 212837Sgabeblack@google.com * Copyright (c) 2006 The Regents of The University of Michigan 312837Sgabeblack@google.com * All rights reserved. 412837Sgabeblack@google.com * 512837Sgabeblack@google.com * Redistribution and use in source and binary forms, with or without 612837Sgabeblack@google.com * modification, are permitted provided that the following conditions are 712837Sgabeblack@google.com * met: redistributions of source code must retain the above copyright 812837Sgabeblack@google.com * notice, this list of conditions and the following disclaimer; 912837Sgabeblack@google.com * redistributions in binary form must reproduce the above copyright 1012837Sgabeblack@google.com * notice, this list of conditions and the following disclaimer in the 1112837Sgabeblack@google.com * documentation and/or other materials provided with the distribution; 1212837Sgabeblack@google.com * neither the name of the copyright holders nor the names of its 1312837Sgabeblack@google.com * contributors may be used to endorse or promote products derived from 1412837Sgabeblack@google.com * this software without specific prior written permission. 1512837Sgabeblack@google.com * 1612837Sgabeblack@google.com * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 1712837Sgabeblack@google.com * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 1812837Sgabeblack@google.com * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 1912837Sgabeblack@google.com * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 2012837Sgabeblack@google.com * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 2112837Sgabeblack@google.com * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 2212837Sgabeblack@google.com * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 2312837Sgabeblack@google.com * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 2412837Sgabeblack@google.com * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 2512837Sgabeblack@google.com * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 2612837Sgabeblack@google.com * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 2712837Sgabeblack@google.com * 2812837Sgabeblack@google.com * Authors: Ron Dreslinski 2912837Sgabeblack@google.com * Steve Reinhardt 3012837Sgabeblack@google.com * Ali Saidi 3112837Sgabeblack@google.com */ 3212837Sgabeblack@google.com 3312837Sgabeblack@google.com/** 3412837Sgabeblack@google.com * @file 3512837Sgabeblack@google.com * Declaration of the Packet class. 3612837Sgabeblack@google.com */ 3712837Sgabeblack@google.com 3812837Sgabeblack@google.com#ifndef __MEM_PACKET_HH__ 3912837Sgabeblack@google.com#define __MEM_PACKET_HH__ 4012837Sgabeblack@google.com 4112837Sgabeblack@google.com#include <cassert> 4212837Sgabeblack@google.com#include <list> 4312837Sgabeblack@google.com 4412837Sgabeblack@google.com#include "mem/request.hh" 4512837Sgabeblack@google.com#include "sim/host.hh" 4612837Sgabeblack@google.com#include "sim/root.hh" 4712837Sgabeblack@google.com 4812837Sgabeblack@google.comstruct Packet; 4912837Sgabeblack@google.comtypedef Packet* PacketPtr; 5012837Sgabeblack@google.comtypedef uint8_t* PacketDataPtr; 5112837Sgabeblack@google.comtypedef std::list<PacketPtr> PacketList; 5212837Sgabeblack@google.com 5312837Sgabeblack@google.com//Coherence Flags 5412837Sgabeblack@google.com#define NACKED_LINE 1 << 0 5512837Sgabeblack@google.com#define SATISFIED 1 << 1 5612837Sgabeblack@google.com#define SHARED_LINE 1 << 2 5712837Sgabeblack@google.com#define CACHE_LINE_FILL 1 << 3 5812837Sgabeblack@google.com#define COMPRESSED 1 << 4 5912837Sgabeblack@google.com#define NO_ALLOCATE 1 << 5 6012837Sgabeblack@google.com#define SNOOP_COMMIT 1 << 6 6112837Sgabeblack@google.com 6212837Sgabeblack@google.com//for now. @todo fix later 6312837Sgabeblack@google.com#define NUM_MEM_CMDS 1 << 11 6412837Sgabeblack@google.com/** 6512837Sgabeblack@google.com * A Packet is used to encapsulate a transfer between two objects in 6612837Sgabeblack@google.com * the memory system (e.g., the L1 and L2 cache). (In contrast, a 6712837Sgabeblack@google.com * single Request travels all the way from the requester to the 6812837Sgabeblack@google.com * ultimate destination and back, possibly being conveyed by several 6912837Sgabeblack@google.com * different Packets along the way.) 7012837Sgabeblack@google.com */ 7112837Sgabeblack@google.comclass Packet 7212837Sgabeblack@google.com{ 7312837Sgabeblack@google.com public: 7412837Sgabeblack@google.com /** Temporary FLAGS field until cache gets working, this should be in coherence/sender state. */ 7512837Sgabeblack@google.com uint64_t flags; 7612837Sgabeblack@google.com 7712837Sgabeblack@google.com private: 7812837Sgabeblack@google.com /** A pointer to the data being transfered. It can be differnt 7912837Sgabeblack@google.com * sizes at each level of the heirarchy so it belongs in the 8012837Sgabeblack@google.com * packet, not request. This may or may not be populated when a 8112837Sgabeblack@google.com * responder recieves the packet. If not populated it memory 8212837Sgabeblack@google.com * should be allocated. 8312837Sgabeblack@google.com */ 8412837Sgabeblack@google.com PacketDataPtr data; 8512837Sgabeblack@google.com 8612837Sgabeblack@google.com /** Is the data pointer set to a value that shouldn't be freed 8712837Sgabeblack@google.com * when the packet is destroyed? */ 8812837Sgabeblack@google.com bool staticData; 8912837Sgabeblack@google.com /** The data pointer points to a value that should be freed when 9012837Sgabeblack@google.com * the packet is destroyed. */ 9112837Sgabeblack@google.com bool dynamicData; 9212837Sgabeblack@google.com /** the data pointer points to an array (thus delete [] ) needs to 9312837Sgabeblack@google.com * be called on it rather than simply delete.*/ 9412837Sgabeblack@google.com bool arrayData; 9512837Sgabeblack@google.com 9612837Sgabeblack@google.com /** The address of the request. This address could be virtual or 9712837Sgabeblack@google.com * physical, depending on the system configuration. */ 9812837Sgabeblack@google.com Addr addr; 9912837Sgabeblack@google.com 10012837Sgabeblack@google.com /** The size of the request or transfer. */ 10112837Sgabeblack@google.com int size; 10212837Sgabeblack@google.com 10312837Sgabeblack@google.com /** Device address (e.g., bus ID) of the source of the 10412837Sgabeblack@google.com * transaction. The source is not responsible for setting this 10512837Sgabeblack@google.com * field; it is set implicitly by the interconnect when the 10612837Sgabeblack@google.com * packet * is first sent. */ 10712837Sgabeblack@google.com short src; 10812837Sgabeblack@google.com 10912837Sgabeblack@google.com /** Device address (e.g., bus ID) of the destination of the 11012837Sgabeblack@google.com * transaction. The special value Broadcast indicates that the 11112837Sgabeblack@google.com * packet should be routed based on its address. This field is 11212837Sgabeblack@google.com * initialized in the constructor and is thus always valid 11312837Sgabeblack@google.com * (unlike * addr, size, and src). */ 11412837Sgabeblack@google.com short dest; 11512837Sgabeblack@google.com 11612837Sgabeblack@google.com /** Are the 'addr' and 'size' fields valid? */ 11712837Sgabeblack@google.com bool addrSizeValid; 11812837Sgabeblack@google.com /** Is the 'src' field valid? */ 11912837Sgabeblack@google.com bool srcValid; 12012837Sgabeblack@google.com 12112837Sgabeblack@google.com 12212837Sgabeblack@google.com public: 12312837Sgabeblack@google.com 12412837Sgabeblack@google.com /** Used to calculate latencies for each packet.*/ 12512837Sgabeblack@google.com Tick time; 12612837Sgabeblack@google.com 12712837Sgabeblack@google.com /** The time at which the packet will be fully transmitted */ 12812837Sgabeblack@google.com Tick finishTime; 12912837Sgabeblack@google.com 13012837Sgabeblack@google.com /** The time at which the first chunk of the packet will be transmitted */ 13112837Sgabeblack@google.com Tick firstWordTime; 13212837Sgabeblack@google.com 13312837Sgabeblack@google.com /** The special destination address indicating that the packet 13412837Sgabeblack@google.com * should be routed based on its address. */ 13512837Sgabeblack@google.com static const short Broadcast = -1; 13612837Sgabeblack@google.com 13712837Sgabeblack@google.com /** A pointer to the original request. */ 13812837Sgabeblack@google.com RequestPtr req; 13912837Sgabeblack@google.com 14012837Sgabeblack@google.com /** A virtual base opaque structure used to hold coherence-related 14112837Sgabeblack@google.com * state. A specific subclass would be derived from this to 14212837Sgabeblack@google.com * carry state specific to a particular coherence protocol. */ 14312837Sgabeblack@google.com class CoherenceState { 14412864Sgabeblack@google.com public: 14512864Sgabeblack@google.com virtual ~CoherenceState() {} 14612864Sgabeblack@google.com }; 14712837Sgabeblack@google.com 14812837Sgabeblack@google.com /** This packet's coherence state. Caches should use 14912837Sgabeblack@google.com * dynamic_cast<> to cast to the state appropriate for the 15012837Sgabeblack@google.com * system's coherence protocol. */ 15112837Sgabeblack@google.com CoherenceState *coherence; 15212837Sgabeblack@google.com 15312837Sgabeblack@google.com /** A virtual base opaque structure used to hold state associated 15412837Sgabeblack@google.com * with the packet but specific to the sending device (e.g., an 15512837Sgabeblack@google.com * MSHR). A pointer to this state is returned in the packet's 15612837Sgabeblack@google.com * response so that the sender can quickly look up the state 15712837Sgabeblack@google.com * needed to process it. A specific subclass would be derived 15812837Sgabeblack@google.com * from this to carry state specific to a particular sending 15912837Sgabeblack@google.com * device. */ 16012837Sgabeblack@google.com class SenderState { 16112837Sgabeblack@google.com public: 16212837Sgabeblack@google.com virtual ~SenderState() {} 16312837Sgabeblack@google.com }; 16412837Sgabeblack@google.com 16512837Sgabeblack@google.com /** This packet's sender state. Devices should use dynamic_cast<> 16612837Sgabeblack@google.com * to cast to the state appropriate to the sender. */ 16712837Sgabeblack@google.com SenderState *senderState; 16812837Sgabeblack@google.com 16912837Sgabeblack@google.com private: 17012837Sgabeblack@google.com /** List of command attributes. */ 17112837Sgabeblack@google.com // If you add a new CommandAttribute, make sure to increase NUM_MEM_CMDS 17212837Sgabeblack@google.com // as well. 17312837Sgabeblack@google.com enum CommandAttribute 17412837Sgabeblack@google.com { 17512837Sgabeblack@google.com IsRead = 1 << 0, 17612837Sgabeblack@google.com IsWrite = 1 << 1, 17712837Sgabeblack@google.com IsPrefetch = 1 << 2, 17812837Sgabeblack@google.com IsInvalidate = 1 << 3, 17912837Sgabeblack@google.com IsRequest = 1 << 4, 18012837Sgabeblack@google.com IsResponse = 1 << 5, 18112837Sgabeblack@google.com NeedsResponse = 1 << 6, 18212837Sgabeblack@google.com IsSWPrefetch = 1 << 7, 18312837Sgabeblack@google.com IsHWPrefetch = 1 << 8, 18412837Sgabeblack@google.com IsUpgrade = 1 << 9, 18512837Sgabeblack@google.com HasData = 1 << 10 18612837Sgabeblack@google.com }; 18712837Sgabeblack@google.com 18812837Sgabeblack@google.com public: 18912837Sgabeblack@google.com /** List of all commands associated with a packet. */ 19012837Sgabeblack@google.com enum Command 19112837Sgabeblack@google.com { 19212837Sgabeblack@google.com InvalidCmd = 0, 19312837Sgabeblack@google.com ReadReq = IsRead | IsRequest | NeedsResponse, 19412837Sgabeblack@google.com WriteReq = IsWrite | IsRequest | NeedsResponse | HasData, 19512837Sgabeblack@google.com WriteReqNoAck = IsWrite | IsRequest | HasData, 19612837Sgabeblack@google.com ReadResp = IsRead | IsResponse | NeedsResponse | HasData, 19712837Sgabeblack@google.com WriteResp = IsWrite | IsResponse | NeedsResponse, 19812837Sgabeblack@google.com Writeback = IsWrite | IsRequest | HasData, 19912837Sgabeblack@google.com SoftPFReq = IsRead | IsRequest | IsSWPrefetch | NeedsResponse, 20012837Sgabeblack@google.com HardPFReq = IsRead | IsRequest | IsHWPrefetch | NeedsResponse, 20112837Sgabeblack@google.com SoftPFResp = IsRead | IsResponse | IsSWPrefetch 20212837Sgabeblack@google.com | NeedsResponse | HasData, 20312837Sgabeblack@google.com HardPFResp = IsRead | IsResponse | IsHWPrefetch 20412837Sgabeblack@google.com | NeedsResponse | HasData, 20512837Sgabeblack@google.com InvalidateReq = IsInvalidate | IsRequest, 20612837Sgabeblack@google.com WriteInvalidateReq = IsWrite | IsInvalidate | IsRequest 20712837Sgabeblack@google.com | HasData | NeedsResponse, 20812837Sgabeblack@google.com WriteInvalidateResp = IsWrite | IsInvalidate | IsRequest | NeedsResponse 20912837Sgabeblack@google.com | IsResponse, 21012837Sgabeblack@google.com UpgradeReq = IsInvalidate | IsRequest | IsUpgrade, 21112837Sgabeblack@google.com ReadExReq = IsRead | IsInvalidate | IsRequest | NeedsResponse, 21212837Sgabeblack@google.com ReadExResp = IsRead | IsInvalidate | IsResponse 21312837Sgabeblack@google.com | NeedsResponse | HasData 21412837Sgabeblack@google.com }; 21512837Sgabeblack@google.com 21612837Sgabeblack@google.com /** Return the string name of the cmd field (for debugging and 21712837Sgabeblack@google.com * tracing). */ 21812837Sgabeblack@google.com const std::string &cmdString() const; 21912837Sgabeblack@google.com 22012837Sgabeblack@google.com /** Reutrn the string to a cmd given by idx. */ 22112837Sgabeblack@google.com const std::string &cmdIdxToString(Command idx); 22212837Sgabeblack@google.com 22312837Sgabeblack@google.com /** Return the index of this command. */ 22412837Sgabeblack@google.com inline int cmdToIndex() const { return (int) cmd; } 22512837Sgabeblack@google.com 22612837Sgabeblack@google.com /** The command field of the packet. */ 22712837Sgabeblack@google.com Command cmd; 22812837Sgabeblack@google.com 22912837Sgabeblack@google.com bool isRead() const { return (cmd & IsRead) != 0; } 23012837Sgabeblack@google.com bool isWrite() const { return (cmd & IsWrite) != 0; } 23112837Sgabeblack@google.com bool isRequest() const { return (cmd & IsRequest) != 0; } 23212837Sgabeblack@google.com bool isResponse() const { return (cmd & IsResponse) != 0; } 23312837Sgabeblack@google.com bool needsResponse() const { return (cmd & NeedsResponse) != 0; } 23412837Sgabeblack@google.com bool isInvalidate() const { return (cmd & IsInvalidate) != 0; } 23512837Sgabeblack@google.com bool hasData() const { return (cmd & HasData) != 0; } 23612837Sgabeblack@google.com 23712837Sgabeblack@google.com bool isCacheFill() const { return (flags & CACHE_LINE_FILL) != 0; } 23812837Sgabeblack@google.com bool isNoAllocate() const { return (flags & NO_ALLOCATE) != 0; } 23912837Sgabeblack@google.com bool isCompressed() const { return (flags & COMPRESSED) != 0; } 24012837Sgabeblack@google.com 24112837Sgabeblack@google.com bool nic_pkt() { assert("Unimplemented\n" && 0); return false; } 24212837Sgabeblack@google.com 24312837Sgabeblack@google.com /** Possible results of a packet's request. */ 24412837Sgabeblack@google.com enum Result 24512837Sgabeblack@google.com { 24612837Sgabeblack@google.com Success, 24712901Sgabeblack@google.com BadAddress, 24812901Sgabeblack@google.com Nacked, 24912901Sgabeblack@google.com Unknown 25012901Sgabeblack@google.com }; 25112901Sgabeblack@google.com 25212901Sgabeblack@google.com /** The result of this packet's request. */ 25312837Sgabeblack@google.com Result result; 25412837Sgabeblack@google.com 25512837Sgabeblack@google.com /** Accessor function that returns the source index of the packet. */ 256 short getSrc() const { assert(srcValid); return src; } 257 void setSrc(short _src) { src = _src; srcValid = true; } 258 259 /** Accessor function that returns the destination index of 260 the packet. */ 261 short getDest() const { return dest; } 262 void setDest(short _dest) { dest = _dest; } 263 264 Addr getAddr() const { assert(addrSizeValid); return addr; } 265 int getSize() const { assert(addrSizeValid); return size; } 266 Addr getOffset(int blkSize) const { return addr & (Addr)(blkSize - 1); } 267 268 void addrOverride(Addr newAddr) { assert(addrSizeValid); addr = newAddr; } 269 void cmdOverride(Command newCmd) { cmd = newCmd; } 270 271 /** Constructor. Note that a Request object must be constructed 272 * first, but the Requests's physical address and size fields 273 * need not be valid. The command and destination addresses 274 * must be supplied. */ 275 Packet(Request *_req, Command _cmd, short _dest) 276 : data(NULL), staticData(false), dynamicData(false), arrayData(false), 277 addr(_req->paddr), size(_req->size), dest(_dest), 278 addrSizeValid(_req->validPaddr), 279 srcValid(false), 280 req(_req), coherence(NULL), senderState(NULL), cmd(_cmd), 281 result(Unknown) 282 { 283 flags = 0; 284 time = curTick; 285 } 286 287 /** Alternate constructor if you are trying to create a packet with 288 * a request that is for a whole block, not the address from the req. 289 * this allows for overriding the size/addr of the req.*/ 290 Packet(Request *_req, Command _cmd, short _dest, int _blkSize) 291 : data(NULL), staticData(false), dynamicData(false), arrayData(false), 292 addr(_req->paddr & ~(_blkSize - 1)), size(_blkSize), 293 dest(_dest), 294 addrSizeValid(_req->validPaddr), srcValid(false), 295 req(_req), coherence(NULL), senderState(NULL), cmd(_cmd), 296 result(Unknown) 297 { 298 flags = 0; 299 time = curTick; 300 } 301 302 /** Destructor. */ 303 ~Packet() 304 { deleteData(); } 305 306 /** Reinitialize packet address and size from the associated 307 * Request object, and reset other fields that may have been 308 * modified by a previous transaction. Typically called when a 309 * statically allocated Request/Packet pair is reused for 310 * multiple transactions. */ 311 void reinitFromRequest() { 312 assert(req->validPaddr); 313 addr = req->paddr; 314 size = req->size; 315 time = req->time; 316 addrSizeValid = true; 317 result = Unknown; 318 if (dynamicData) { 319 deleteData(); 320 dynamicData = false; 321 arrayData = false; 322 } 323 } 324 325 /** Take a request packet and modify it in place to be suitable 326 * for returning as a response to that request. Used for timing 327 * accesses only. For atomic and functional accesses, the 328 * request packet is always implicitly passed back *without* 329 * modifying the destination fields, so this function 330 * should not be called. */ 331 void makeTimingResponse() { 332 assert(needsResponse()); 333 assert(isRequest()); 334 int icmd = (int)cmd; 335 icmd &= ~(IsRequest); 336 icmd |= IsResponse; 337 if (isRead()) 338 icmd |= HasData; 339 if (isWrite()) 340 icmd &= ~HasData; 341 cmd = (Command)icmd; 342 dest = src; 343 srcValid = false; 344 } 345 346 /** 347 * Take a request packet and modify it in place to be suitable for 348 * returning as a response to that request. 349 */ 350 void makeAtomicResponse() 351 { 352 assert(needsResponse()); 353 assert(isRequest()); 354 int icmd = (int)cmd; 355 icmd &= ~(IsRequest); 356 icmd |= IsResponse; 357 if (isRead()) 358 icmd |= HasData; 359 if (isWrite()) 360 icmd &= ~HasData; 361 cmd = (Command)icmd; 362 } 363 364 /** 365 * Take a request packet that has been returned as NACKED and 366 * modify it so that it can be sent out again. Only packets that 367 * need a response can be NACKED, so verify that that is true. 368 */ 369 void 370 reinitNacked() 371 { 372 assert(needsResponse() && result == Nacked); 373 dest = Broadcast; 374 result = Unknown; 375 } 376 377 378 /** 379 * Set the data pointer to the following value that should not be 380 * freed. 381 */ 382 template <typename T> 383 void 384 dataStatic(T *p) 385 { 386 if(dynamicData) 387 dynamicData = false; 388 data = (PacketDataPtr)p; 389 staticData = true; 390 } 391 392 /** 393 * Set the data pointer to a value that should have delete [] 394 * called on it. 395 */ 396 template <typename T> 397 void 398 dataDynamicArray(T *p) 399 { 400 assert(!staticData && !dynamicData); 401 data = (PacketDataPtr)p; 402 dynamicData = true; 403 arrayData = true; 404 } 405 406 /** 407 * set the data pointer to a value that should have delete called 408 * on it. 409 */ 410 template <typename T> 411 void 412 dataDynamic(T *p) 413 { 414 assert(!staticData && !dynamicData); 415 data = (PacketDataPtr)p; 416 dynamicData = true; 417 arrayData = false; 418 } 419 420 /** get a pointer to the data ptr. */ 421 template <typename T> 422 T* 423 getPtr() 424 { 425 assert(staticData || dynamicData); 426 return (T*)data; 427 } 428 429 /** return the value of what is pointed to in the packet. */ 430 template <typename T> 431 T get(); 432 433 /** set the value in the data pointer to v. */ 434 template <typename T> 435 void set(T v); 436 437 /** 438 * delete the data pointed to in the data pointer. Ok to call to 439 * matter how data was allocted. 440 */ 441 void deleteData(); 442 443 /** If there isn't data in the packet, allocate some. */ 444 void allocate(); 445 446 /** Do the packet modify the same addresses. */ 447 bool intersect(Packet *p); 448}; 449 450 451/** This function given a functional packet and a timing packet either satisfies 452 * the timing packet, or updates the timing packet to reflect the updated state 453 * in the timing packet. It returns if the functional packet should continue to 454 * traverse the memory hierarchy or not. 455 */ 456bool fixPacket(Packet *func, Packet *timing); 457 458std::ostream & operator<<(std::ostream &o, const Packet &p); 459 460#endif //__MEM_PACKET_HH 461