lsq.hh revision 10239
1/* 2 * Copyright (c) 2011-2012 ARM Limited 3 * Copyright (c) 2013 Advanced Micro Devices, Inc. 4 * All rights reserved 5 * 6 * The license below extends only to copyright in the software and shall 7 * not be construed as granting a license to any other intellectual 8 * property including but not limited to intellectual property relating 9 * to a hardware implementation of the functionality of the software 10 * licensed hereunder. You may use the software subject to the license 11 * terms below provided that you ensure that this notice is replicated 12 * unmodified and in its entirety in all distributions of the software, 13 * modified or unmodified, in source code or in binary form. 14 * 15 * Copyright (c) 2004-2006 The Regents of The University of Michigan 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: Korey Sewell 42 */ 43 44#ifndef __CPU_O3_LSQ_HH__ 45#define __CPU_O3_LSQ_HH__ 46 47#include <map> 48#include <queue> 49 50#include "cpu/o3/lsq_unit.hh" 51#include "cpu/inst_seq.hh" 52#include "mem/port.hh" 53#include "sim/sim_object.hh" 54 55struct DerivO3CPUParams; 56 57template <class Impl> 58class LSQ { 59 public: 60 typedef typename Impl::O3CPU O3CPU; 61 typedef typename Impl::DynInstPtr DynInstPtr; 62 typedef typename Impl::CPUPol::IEW IEW; 63 typedef typename Impl::CPUPol::LSQUnit LSQUnit; 64 65 /** SMT policy. */ 66 enum LSQPolicy { 67 Dynamic, 68 Partitioned, 69 Threshold 70 }; 71 72 /** Constructs an LSQ with the given parameters. */ 73 LSQ(O3CPU *cpu_ptr, IEW *iew_ptr, DerivO3CPUParams *params); 74 ~LSQ() { 75 if (thread) delete [] thread; 76 } 77 78 /** Returns the name of the LSQ. */ 79 std::string name() const; 80 81 /** Registers statistics of each LSQ unit. */ 82 void regStats(); 83 84 /** Sets the pointer to the list of active threads. */ 85 void setActiveThreads(std::list<ThreadID> *at_ptr); 86 87 /** Perform sanity checks after a drain. */ 88 void drainSanityCheck() const; 89 /** Has the LSQ drained? */ 90 bool isDrained() const; 91 /** Takes over execution from another CPU's thread. */ 92 void takeOverFrom(); 93 94 /** Number of entries needed for the given amount of threads.*/ 95 int entryAmount(ThreadID num_threads); 96 void removeEntries(ThreadID tid); 97 /** Reset the max entries for each thread. */ 98 void resetEntries(); 99 /** Resize the max entries for a thread. */ 100 void resizeEntries(unsigned size, ThreadID tid); 101 102 /** Ticks the LSQ. */ 103 void tick(); 104 /** Ticks a specific LSQ Unit. */ 105 void tick(ThreadID tid) 106 { thread[tid].tick(); } 107 108 /** Inserts a load into the LSQ. */ 109 void insertLoad(DynInstPtr &load_inst); 110 /** Inserts a store into the LSQ. */ 111 void insertStore(DynInstPtr &store_inst); 112 113 /** Executes a load. */ 114 Fault executeLoad(DynInstPtr &inst); 115 116 /** Executes a store. */ 117 Fault executeStore(DynInstPtr &inst); 118 119 /** 120 * Commits loads up until the given sequence number for a specific thread. 121 */ 122 void commitLoads(InstSeqNum &youngest_inst, ThreadID tid) 123 { thread[tid].commitLoads(youngest_inst); } 124 125 /** 126 * Commits stores up until the given sequence number for a specific thread. 127 */ 128 void commitStores(InstSeqNum &youngest_inst, ThreadID tid) 129 { thread[tid].commitStores(youngest_inst); } 130 131 /** 132 * Attempts to write back stores until all cache ports are used or the 133 * interface becomes blocked. 134 */ 135 void writebackStores(); 136 /** Same as above, but only for one thread. */ 137 void writebackStores(ThreadID tid); 138 139 /** 140 * Squash instructions from a thread until the specified sequence number. 141 */ 142 void squash(const InstSeqNum &squashed_num, ThreadID tid) 143 { thread[tid].squash(squashed_num); } 144 145 /** Returns whether or not there was a memory ordering violation. */ 146 bool violation(); 147 /** 148 * Returns whether or not there was a memory ordering violation for a 149 * specific thread. 150 */ 151 bool violation(ThreadID tid) 152 { return thread[tid].violation(); } 153 154 /** Returns if a load is blocked due to the memory system for a specific 155 * thread. 156 */ 157 bool loadBlocked(ThreadID tid) 158 { return thread[tid].loadBlocked(); } 159 160 bool isLoadBlockedHandled(ThreadID tid) 161 { return thread[tid].isLoadBlockedHandled(); } 162 163 void setLoadBlockedHandled(ThreadID tid) 164 { thread[tid].setLoadBlockedHandled(); } 165 166 /** Gets the instruction that caused the memory ordering violation. */ 167 DynInstPtr getMemDepViolator(ThreadID tid) 168 { return thread[tid].getMemDepViolator(); } 169 170 /** Returns the head index of the load queue for a specific thread. */ 171 int getLoadHead(ThreadID tid) 172 { return thread[tid].getLoadHead(); } 173 174 /** Returns the sequence number of the head of the load queue. */ 175 InstSeqNum getLoadHeadSeqNum(ThreadID tid) 176 { 177 return thread[tid].getLoadHeadSeqNum(); 178 } 179 180 /** Returns the head index of the store queue. */ 181 int getStoreHead(ThreadID tid) 182 { return thread[tid].getStoreHead(); } 183 184 /** Returns the sequence number of the head of the store queue. */ 185 InstSeqNum getStoreHeadSeqNum(ThreadID tid) 186 { 187 return thread[tid].getStoreHeadSeqNum(); 188 } 189 190 /** Returns the number of instructions in all of the queues. */ 191 int getCount(); 192 /** Returns the number of instructions in the queues of one thread. */ 193 int getCount(ThreadID tid) 194 { return thread[tid].getCount(); } 195 196 /** Returns the total number of loads in the load queue. */ 197 int numLoads(); 198 /** Returns the total number of loads for a single thread. */ 199 int numLoads(ThreadID tid) 200 { return thread[tid].numLoads(); } 201 202 /** Returns the total number of stores in the store queue. */ 203 int numStores(); 204 /** Returns the total number of stores for a single thread. */ 205 int numStores(ThreadID tid) 206 { return thread[tid].numStores(); } 207 208 /** Returns the number of free load entries. */ 209 unsigned numFreeLoadEntries(); 210 211 /** Returns the number of free store entries. */ 212 unsigned numFreeStoreEntries(); 213 214 /** Returns the number of free entries for a specific thread. */ 215 unsigned numFreeEntries(ThreadID tid); 216 217 /** Returns the number of free entries in the LQ for a specific thread. */ 218 unsigned numFreeLoadEntries(ThreadID tid); 219 220 /** Returns the number of free entries in the SQ for a specific thread. */ 221 unsigned numFreeStoreEntries(ThreadID tid); 222 223 /** Returns if the LSQ is full (either LQ or SQ is full). */ 224 bool isFull(); 225 /** 226 * Returns if the LSQ is full for a specific thread (either LQ or SQ is 227 * full). 228 */ 229 bool isFull(ThreadID tid); 230 231 /** Returns if the LSQ is empty (both LQ and SQ are empty). */ 232 bool isEmpty() const; 233 /** Returns if all of the LQs are empty. */ 234 bool lqEmpty() const; 235 /** Returns if all of the SQs are empty. */ 236 bool sqEmpty() const; 237 238 /** Returns if any of the LQs are full. */ 239 bool lqFull(); 240 /** Returns if the LQ of a given thread is full. */ 241 bool lqFull(ThreadID tid); 242 243 /** Returns if any of the SQs are full. */ 244 bool sqFull(); 245 /** Returns if the SQ of a given thread is full. */ 246 bool sqFull(ThreadID tid); 247 248 /** 249 * Returns if the LSQ is stalled due to a memory operation that must be 250 * replayed. 251 */ 252 bool isStalled(); 253 /** 254 * Returns if the LSQ of a specific thread is stalled due to a memory 255 * operation that must be replayed. 256 */ 257 bool isStalled(ThreadID tid); 258 259 /** Returns whether or not there are any stores to write back to memory. */ 260 bool hasStoresToWB(); 261 262 /** Returns whether or not a specific thread has any stores to write back 263 * to memory. 264 */ 265 bool hasStoresToWB(ThreadID tid) 266 { return thread[tid].hasStoresToWB(); } 267 268 /** Returns the number of stores a specific thread has to write back. */ 269 int numStoresToWB(ThreadID tid) 270 { return thread[tid].numStoresToWB(); } 271 272 /** Returns if the LSQ will write back to memory this cycle. */ 273 bool willWB(); 274 /** Returns if the LSQ of a specific thread will write back to memory this 275 * cycle. 276 */ 277 bool willWB(ThreadID tid) 278 { return thread[tid].willWB(); } 279 280 /** Returns if the cache is currently blocked. */ 281 bool cacheBlocked() const 282 { return retryTid != InvalidThreadID; } 283 284 /** Sets the retry thread id, indicating that one of the LSQUnits 285 * tried to access the cache but the cache was blocked. */ 286 void setRetryTid(ThreadID tid) 287 { retryTid = tid; } 288 289 /** Debugging function to print out all instructions. */ 290 void dumpInsts() const; 291 /** Debugging function to print out instructions from a specific thread. */ 292 void dumpInsts(ThreadID tid) const 293 { thread[tid].dumpInsts(); } 294 295 /** Executes a read operation, using the load specified at the load 296 * index. 297 */ 298 Fault read(RequestPtr req, RequestPtr sreqLow, RequestPtr sreqHigh, 299 uint8_t *data, int load_idx); 300 301 /** Executes a store operation, using the store specified at the store 302 * index. 303 */ 304 Fault write(RequestPtr req, RequestPtr sreqLow, RequestPtr sreqHigh, 305 uint8_t *data, int store_idx); 306 307 /** 308 * Retry the previous send that failed. 309 */ 310 void recvRetry(); 311 312 /** 313 * Handles writing back and completing the load or store that has 314 * returned from memory. 315 * 316 * @param pkt Response packet from the memory sub-system 317 */ 318 bool recvTimingResp(PacketPtr pkt); 319 320 void recvTimingSnoopReq(PacketPtr pkt); 321 322 /** The CPU pointer. */ 323 O3CPU *cpu; 324 325 /** The IEW stage pointer. */ 326 IEW *iewStage; 327 328 protected: 329 /** The LSQ policy for SMT mode. */ 330 LSQPolicy lsqPolicy; 331 332 /** The LSQ units for individual threads. */ 333 LSQUnit *thread; 334 335 /** List of Active Threads in System. */ 336 std::list<ThreadID> *activeThreads; 337 338 /** Total Size of LQ Entries. */ 339 unsigned LQEntries; 340 /** Total Size of SQ Entries. */ 341 unsigned SQEntries; 342 343 /** Max LQ Size - Used to Enforce Sharing Policies. */ 344 unsigned maxLQEntries; 345 346 /** Max SQ Size - Used to Enforce Sharing Policies. */ 347 unsigned maxSQEntries; 348 349 /** Number of Threads. */ 350 ThreadID numThreads; 351 352 /** The thread id of the LSQ Unit that is currently waiting for a 353 * retry. */ 354 ThreadID retryTid; 355}; 356 357template <class Impl> 358Fault 359LSQ<Impl>::read(RequestPtr req, RequestPtr sreqLow, RequestPtr sreqHigh, 360 uint8_t *data, int load_idx) 361{ 362 ThreadID tid = req->threadId(); 363 364 return thread[tid].read(req, sreqLow, sreqHigh, data, load_idx); 365} 366 367template <class Impl> 368Fault 369LSQ<Impl>::write(RequestPtr req, RequestPtr sreqLow, RequestPtr sreqHigh, 370 uint8_t *data, int store_idx) 371{ 372 ThreadID tid = req->threadId(); 373 374 return thread[tid].write(req, sreqLow, sreqHigh, data, store_idx); 375} 376 377#endif // __CPU_O3_LSQ_HH__ 378