src/mem/request.hh

   1 /*
   2  * Copyright (c) 2002-2005 The Regents of The University of Michigan
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are
   7  * met: redistributions of source code must retain the above copyright
   8  * notice, this list of conditions and the following disclaimer;
   9  * redistributions in binary form must reproduce the above copyright
  10  * notice, this list of conditions and the following disclaimer in the
  11  * documentation and/or other materials provided with the distribution;
  12  * neither the name of the copyright holders nor the names of its
  13  * contributors may be used to endorse or promote products derived from
  14  * this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  17  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  18  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  19  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  20  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  21  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  22  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  26  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  *
  28  * Authors: Ron Dreslinski
  29  *          Steve Reinhardt
  30  *          Ali Saidi
  31  */
  32
  33 /**
  34  * @file
  35  * Declaration of a request, the overall memory request consisting of
  36  the parts of the request that are persistent throughout the transaction.
  37  */
  38
  39 #ifndef __MEM_REQUEST_HH__
  40 #define __MEM_REQUEST_HH__
  41
  42 #include "sim/host.hh"
  43 #include "sim/root.hh"
  44
  45 #include <cassert>
  46
  47 class Request;
  48
  49 typedef Request* RequestPtr;
  50
  51
  52 /** The request is a Load locked/store conditional. */
  53 const unsigned LOCKED           = 0x001;
  54 /** The virtual address is also the physical address. */
  55 const unsigned PHYSICAL         = 0x002;
  56 /** The request is an ALPHA VPTE pal access (hw_ld). */
  57 const unsigned VPTE             = 0x004;
  58 /** Use the alternate mode bits in ALPHA. */
  59 const unsigned ALTMODE          = 0x008;
  60 /** The request is to an uncacheable address. */
  61 const unsigned UNCACHEABLE      = 0x010;
  62 /** The request should not cause a page fault. */
  63 const unsigned NO_FAULT         = 0x020;
  64 /** The request should be prefetched into the exclusive state. */
  65 const unsigned PF_EXCLUSIVE     = 0x100;
  66 /** The request should be marked as LRU. */
  67 const unsigned EVICT_NEXT       = 0x200;
  68 /** The request should ignore unaligned access faults */
  69 const unsigned NO_ALIGN_FAULT   = 0x400;
  70 /** The request was an instruction read. */
  71 const unsigned INST_READ        = 0x800;
  72
  73 class Request
  74 {
  75   private:
  76     /**
  77      * The physical address of the request. Valid only if validPaddr
  78      * is set. */
  79     Addr paddr;
  80
  81     /**
  82      * The size of the request. This field must be set when vaddr or
  83      * paddr is written via setVirt() or setPhys(), so it is always
  84      * valid as long as one of the address fields is valid.  */
  85     int size;
  86
  87     /** Flag structure for the request. */
  88     uint32_t flags;
  89
  90     /**
  91      * The time this request was started. Used to calculate
  92      * latencies. This field is set to curTick any time paddr or vaddr
  93      * is written.  */
  94     Tick time;
  95
  96     /** The address space ID. */
  97     int asid;
  98     /** The virtual address of the request. */
  99     Addr vaddr;
 100
 101     /** The return value of store conditional. */
 102     uint64_t scResult;
 103
 104     /** The cpu number (for statistics, typically). */
 105     int cpuNum;
 106     /** The requesting thread id (for statistics, typically). */
 107     int  threadNum;
 108
 109     /** program counter of initiating access; for tracing/debugging */
 110     Addr pc;
 111
 112     /** Whether or not paddr is valid (has been written yet). */
 113     bool validPaddr;
 114     /** Whether or not the asid & vaddr are valid. */
 115     bool validAsidVaddr;
 116     /** Whether or not the sc result is valid. */
 117     bool validScResult;
 118     /** Whether or not the cpu number & thread ID are valid. */
 119     bool validCpuAndThreadNums;
 120     /** Whether or not the pc is valid. */
 121     bool validPC;
 122
 123   public:
 124     /** Minimal constructor.  No fields are initialized. */
 125     Request()
 126         : validPaddr(false), validAsidVaddr(false),
 127           validScResult(false), validCpuAndThreadNums(false), validPC(false)
 128     {}
 129
 130     /**
 131      * Constructor for physical (e.g. device) requests.  Initializes
 132      * just physical address, size, flags, and timestamp (to curTick).
 133      * These fields are adequate to perform a request.  */
 134     Request(Addr _paddr, int _size, int _flags)
 135         : validCpuAndThreadNums(false)
 136     { setPhys(_paddr, _size, _flags); }
 137
 138     Request(int _asid, Addr _vaddr, int _size, int _flags, Addr _pc,
 139             int _cpuNum, int _threadNum)
 140     {
 141         setThreadContext(_cpuNum, _threadNum);
 142         setVirt(_asid, _vaddr, _size, _flags, _pc);
 143     }
 144
 145     /**
 146      * Set up CPU and thread numbers. */
 147     void setThreadContext(int _cpuNum, int _threadNum)
 148     {
 149         cpuNum = _cpuNum;
 150         threadNum = _threadNum;
 151         validCpuAndThreadNums = true;
 152     }
 153
 154     /**
 155      * Set up a physical (e.g. device) request in a previously
 156      * allocated Request object. */
 157     void setPhys(Addr _paddr, int _size, int _flags)
 158     {
 159         paddr = _paddr;
 160         size = _size;
 161         flags = _flags;
 162         time = curTick;
 163         validPaddr = true;
 164         validAsidVaddr = false;
 165         validPC = false;
 166         validScResult = false;
 167     }
 168
 169     /**
 170      * Set up a virtual (e.g., CPU) request in a previously
 171      * allocated Request object. */
 172     void setVirt(int _asid, Addr _vaddr, int _size, int _flags, Addr _pc)
 173     {
 174         asid = _asid;
 175         vaddr = _vaddr;
 176         size = _size;
 177         flags = _flags;
 178         pc = _pc;
 179         time = curTick;
 180         validPaddr = false;
 181         validAsidVaddr = true;
 182         validPC = true;
 183         validScResult = false;
 184     }
 185
 186     /** Set just the physical address.  This should only be used to
 187      * record the result of a translation, and thus the vaddr must be
 188      * valid before this method is called.  Otherwise, use setPhys()
 189      * to guarantee that the size and flags are also set.
 190      */
 191     void setPaddr(Addr _paddr)
 192     {
 193         assert(validAsidVaddr);
 194         paddr = _paddr;
 195         validPaddr = true;
 196     }
 197
 198     /** Accessor for paddr. */
 199     Addr getPaddr() { assert(validPaddr); return paddr; }
 200
 201     /** Accessor for size. */
 202     int getSize() { assert(validPaddr || validAsidVaddr); return size; }
 203     /** Accessor for time. */
 204     Tick getTime() { assert(validPaddr || validAsidVaddr); return time; }
 205
 206     /** Accessor for flags. */
 207     uint32_t getFlags() { assert(validPaddr || validAsidVaddr); return flags; }
 208     /** Accessor for paddr. */
 209     void setFlags(uint32_t _flags)
 210     { assert(validPaddr || validAsidVaddr); flags = _flags; }
 211
 212     /** Accessor function for vaddr.*/
 213     Addr getVaddr() { assert(validAsidVaddr); return vaddr; }
 214
 215     /** Accessor function for asid.*/
 216     int getAsid() { assert(validAsidVaddr); return asid; }
 217
 218     /** Accessor function to check if sc result is valid. */
 219     bool scResultValid() { return validScResult; }
 220     /** Accessor function for store conditional return value.*/
 221     uint64_t getScResult() { assert(validScResult); return scResult; }
 222     /** Accessor function for store conditional return value.*/
 223     void setScResult(uint64_t _scResult)
 224     { scResult = _scResult; validScResult = true; }
 225
 226     /** Accessor function for cpu number.*/
 227     int getCpuNum() { assert(validCpuAndThreadNums); return cpuNum; }
 228     /** Accessor function for thread number.*/
 229     int getThreadNum()  { assert(validCpuAndThreadNums); return threadNum; }
 230
 231     /** Accessor function for pc.*/
 232     Addr getPC() { assert(validPC); return pc; }
 233
 234     /** Accessor Function to Check Cacheability. */
 235     bool isUncacheable() { return (getFlags() & UNCACHEABLE) != 0; }
 236
 237     bool isInstRead() { return (getFlags() & INST_READ) != 0; }
 238
 239     bool isLocked() { return (getFlags() & LOCKED) != 0; }
 240
 241     friend class Packet;
 242 };
 243
 244 #endif // __MEM_REQUEST_HH__