lsq.hh revision 9868
1/* 2 * Copyright (c) 2011-2012 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) 2004-2006 The Regents of The University of Michigan 15 * All rights reserved. 16 * 17 * Redistribution and use in source and binary forms, with or without 18 * modification, are permitted provided that the following conditions are 19 * met: redistributions of source code must retain the above copyright 20 * notice, this list of conditions and the following disclaimer; 21 * redistributions in binary form must reproduce the above copyright 22 * notice, this list of conditions and the following disclaimer in the 23 * documentation and/or other materials provided with the distribution; 24 * neither the name of the copyright holders nor the names of its 25 * contributors may be used to endorse or promote products derived from 26 * this software without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 29 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 30 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 31 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 32 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 33 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 34 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 35 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 36 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 37 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 38 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 39 * 40 * Authors: Korey Sewell 41 */ 42 43#ifndef __CPU_O3_LSQ_HH__ 44#define __CPU_O3_LSQ_HH__ 45 46#include <map> 47#include <queue> 48 49#include "cpu/o3/lsq_unit.hh" 50#include "cpu/inst_seq.hh" 51#include "mem/port.hh" 52#include "sim/sim_object.hh" 53 54struct DerivO3CPUParams; 55 56template <class Impl> 57class LSQ { 58 public: 59 typedef typename Impl::O3CPU O3CPU; 60 typedef typename Impl::DynInstPtr DynInstPtr; 61 typedef typename Impl::CPUPol::IEW IEW; 62 typedef typename Impl::CPUPol::LSQUnit LSQUnit; 63 64 /** SMT policy. */ 65 enum LSQPolicy { 66 Dynamic, 67 Partitioned, 68 Threshold 69 }; 70 71 /** Constructs an LSQ with the given parameters. */ 72 LSQ(O3CPU *cpu_ptr, IEW *iew_ptr, DerivO3CPUParams *params); 73 ~LSQ() { 74 if (thread) delete [] thread; 75 } 76 77 /** Returns the name of the LSQ. */ 78 std::string name() const; 79 80 /** Registers statistics of each LSQ unit. */ 81 void regStats(); 82 83 /** Sets the pointer to the list of active threads. */ 84 void setActiveThreads(std::list<ThreadID> *at_ptr); 85 86 /** Perform sanity checks after a drain. */ 87 void drainSanityCheck() const; 88 /** Has the LSQ drained? */ 89 bool isDrained() const; 90 /** Takes over execution from another CPU's thread. */ 91 void takeOverFrom(); 92 93 /** Number of entries needed for the given amount of threads.*/ 94 int entryAmount(ThreadID num_threads); 95 void removeEntries(ThreadID tid); 96 /** Reset the max entries for each thread. */ 97 void resetEntries(); 98 /** Resize the max entries for a thread. */ 99 void resizeEntries(unsigned size, ThreadID tid); 100 101 /** Ticks the LSQ. */ 102 void tick(); 103 /** Ticks a specific LSQ Unit. */ 104 void tick(ThreadID tid) 105 { thread[tid].tick(); } 106 107 /** Inserts a load into the LSQ. */ 108 void insertLoad(DynInstPtr &load_inst); 109 /** Inserts a store into the LSQ. */ 110 void insertStore(DynInstPtr &store_inst); 111 112 /** Executes a load. */ 113 Fault executeLoad(DynInstPtr &inst); 114 115 /** Executes a store. */ 116 Fault executeStore(DynInstPtr &inst); 117 118 /** 119 * Commits loads up until the given sequence number for a specific thread. 120 */ 121 void commitLoads(InstSeqNum &youngest_inst, ThreadID tid) 122 { thread[tid].commitLoads(youngest_inst); } 123 124 /** 125 * Commits stores up until the given sequence number for a specific thread. 126 */ 127 void commitStores(InstSeqNum &youngest_inst, ThreadID tid) 128 { thread[tid].commitStores(youngest_inst); } 129 130 /** 131 * Attempts to write back stores until all cache ports are used or the 132 * interface becomes blocked. 133 */ 134 void writebackStores(); 135 /** Same as above, but only for one thread. */ 136 void writebackStores(ThreadID tid); 137 138 /** 139 * Squash instructions from a thread until the specified sequence number. 140 */ 141 void squash(const InstSeqNum &squashed_num, ThreadID tid) 142 { thread[tid].squash(squashed_num); } 143 144 /** Returns whether or not there was a memory ordering violation. */ 145 bool violation(); 146 /** 147 * Returns whether or not there was a memory ordering violation for a 148 * specific thread. 149 */ 150 bool violation(ThreadID tid) 151 { return thread[tid].violation(); } 152 153 /** Returns if a load is blocked due to the memory system for a specific 154 * thread. 155 */ 156 bool loadBlocked(ThreadID tid) 157 { return thread[tid].loadBlocked(); } 158 159 bool isLoadBlockedHandled(ThreadID tid) 160 { return thread[tid].isLoadBlockedHandled(); } 161 162 void setLoadBlockedHandled(ThreadID tid) 163 { thread[tid].setLoadBlockedHandled(); } 164 165 /** Gets the instruction that caused the memory ordering violation. */ 166 DynInstPtr getMemDepViolator(ThreadID tid) 167 { return thread[tid].getMemDepViolator(); } 168 169 /** Returns the head index of the load queue for a specific thread. */ 170 int getLoadHead(ThreadID tid) 171 { return thread[tid].getLoadHead(); } 172 173 /** Returns the sequence number of the head of the load queue. */ 174 InstSeqNum getLoadHeadSeqNum(ThreadID tid) 175 { 176 return thread[tid].getLoadHeadSeqNum(); 177 } 178 179 /** Returns the head index of the store queue. */ 180 int getStoreHead(ThreadID tid) 181 { return thread[tid].getStoreHead(); } 182 183 /** Returns the sequence number of the head of the store queue. */ 184 InstSeqNum getStoreHeadSeqNum(ThreadID tid) 185 { 186 return thread[tid].getStoreHeadSeqNum(); 187 } 188 189 /** Returns the number of instructions in all of the queues. */ 190 int getCount(); 191 /** Returns the number of instructions in the queues of one thread. */ 192 int getCount(ThreadID tid) 193 { return thread[tid].getCount(); } 194 195 /** Returns the total number of loads in the load queue. */ 196 int numLoads(); 197 /** Returns the total number of loads for a single thread. */ 198 int numLoads(ThreadID tid) 199 { return thread[tid].numLoads(); } 200 201 /** Returns the total number of stores in the store queue. */ 202 int numStores(); 203 /** Returns the total number of stores for a single thread. */ 204 int numStores(ThreadID tid) 205 { return thread[tid].numStores(); } 206 207 /** Returns the number of free entries. */ 208 unsigned numFreeEntries(); 209 /** Returns the number of free entries for a specific thread. */ 210 unsigned numFreeEntries(ThreadID tid); 211 212 /** Returns if the LSQ is full (either LQ or SQ is full). */ 213 bool isFull(); 214 /** 215 * Returns if the LSQ is full for a specific thread (either LQ or SQ is 216 * full). 217 */ 218 bool isFull(ThreadID tid); 219 220 /** Returns if the LSQ is empty (both LQ and SQ are empty). */ 221 bool isEmpty() const; 222 /** Returns if all of the LQs are empty. */ 223 bool lqEmpty() const; 224 /** Returns if all of the SQs are empty. */ 225 bool sqEmpty() const; 226 227 /** Returns if any of the LQs are full. */ 228 bool lqFull(); 229 /** Returns if the LQ of a given thread is full. */ 230 bool lqFull(ThreadID tid); 231 232 /** Returns if any of the SQs are full. */ 233 bool sqFull(); 234 /** Returns if the SQ of a given thread is full. */ 235 bool sqFull(ThreadID tid); 236 237 /** 238 * Returns if the LSQ is stalled due to a memory operation that must be 239 * replayed. 240 */ 241 bool isStalled(); 242 /** 243 * Returns if the LSQ of a specific thread is stalled due to a memory 244 * operation that must be replayed. 245 */ 246 bool isStalled(ThreadID tid); 247 248 /** Returns whether or not there are any stores to write back to memory. */ 249 bool hasStoresToWB(); 250 251 /** Returns whether or not a specific thread has any stores to write back 252 * to memory. 253 */ 254 bool hasStoresToWB(ThreadID tid) 255 { return thread[tid].hasStoresToWB(); } 256 257 /** Returns the number of stores a specific thread has to write back. */ 258 int numStoresToWB(ThreadID tid) 259 { return thread[tid].numStoresToWB(); } 260 261 /** Returns if the LSQ will write back to memory this cycle. */ 262 bool willWB(); 263 /** Returns if the LSQ of a specific thread will write back to memory this 264 * cycle. 265 */ 266 bool willWB(ThreadID tid) 267 { return thread[tid].willWB(); } 268 269 /** Returns if the cache is currently blocked. */ 270 bool cacheBlocked() const 271 { return retryTid != InvalidThreadID; } 272 273 /** Sets the retry thread id, indicating that one of the LSQUnits 274 * tried to access the cache but the cache was blocked. */ 275 void setRetryTid(ThreadID tid) 276 { retryTid = tid; } 277 278 /** Debugging function to print out all instructions. */ 279 void dumpInsts() const; 280 /** Debugging function to print out instructions from a specific thread. */ 281 void dumpInsts(ThreadID tid) const 282 { thread[tid].dumpInsts(); } 283 284 /** Executes a read operation, using the load specified at the load 285 * index. 286 */ 287 Fault read(RequestPtr req, RequestPtr sreqLow, RequestPtr sreqHigh, 288 uint8_t *data, int load_idx); 289 290 /** Executes a store operation, using the store specified at the store 291 * index. 292 */ 293 Fault write(RequestPtr req, RequestPtr sreqLow, RequestPtr sreqHigh, 294 uint8_t *data, int store_idx); 295 296 /** 297 * Retry the previous send that failed. 298 */ 299 void recvRetry(); 300 301 /** 302 * Handles writing back and completing the load or store that has 303 * returned from memory. 304 * 305 * @param pkt Response packet from the memory sub-system 306 */ 307 bool recvTimingResp(PacketPtr pkt); 308 309 void recvTimingSnoopReq(PacketPtr pkt); 310 311 /** The CPU pointer. */ 312 O3CPU *cpu; 313 314 /** The IEW stage pointer. */ 315 IEW *iewStage; 316 317 protected: 318 /** The LSQ policy for SMT mode. */ 319 LSQPolicy lsqPolicy; 320 321 /** The LSQ units for individual threads. */ 322 LSQUnit *thread; 323 324 /** List of Active Threads in System. */ 325 std::list<ThreadID> *activeThreads; 326 327 /** Total Size of LQ Entries. */ 328 unsigned LQEntries; 329 /** Total Size of SQ Entries. */ 330 unsigned SQEntries; 331 332 /** Max LQ Size - Used to Enforce Sharing Policies. */ 333 unsigned maxLQEntries; 334 335 /** Max SQ Size - Used to Enforce Sharing Policies. */ 336 unsigned maxSQEntries; 337 338 /** Number of Threads. */ 339 ThreadID numThreads; 340 341 /** The thread id of the LSQ Unit that is currently waiting for a 342 * retry. */ 343 ThreadID retryTid; 344}; 345 346template <class Impl> 347Fault 348LSQ<Impl>::read(RequestPtr req, RequestPtr sreqLow, RequestPtr sreqHigh, 349 uint8_t *data, int load_idx) 350{ 351 ThreadID tid = req->threadId(); 352 353 return thread[tid].read(req, sreqLow, sreqHigh, data, load_idx); 354} 355 356template <class Impl> 357Fault 358LSQ<Impl>::write(RequestPtr req, RequestPtr sreqLow, RequestPtr sreqHigh, 359 uint8_t *data, int store_idx) 360{ 361 ThreadID tid = req->threadId(); 362 363 return thread[tid].write(req, sreqLow, sreqHigh, data, store_idx); 364} 365 366#endif // __CPU_O3_LSQ_HH__ 367