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 Decleration of a request, the overall memory request consisting of
  35  the parts of the request that are persistent throughout the transaction.
  36  */
  37
  38 #ifndef __MEM_REQUEST_HH__
  39 #define __MEM_REQUEST_HH__
  40
  41 #include "arch/isa_traits.hh"
  42
  43 class Request;
  44
  45 typedef Request* RequestPtr;
  46
  47 /** The request is a Load locked/store conditional. */
  48 const unsigned LOCKED           = 0x001;
  49 /** The virtual address is also the physical address. */
  50 const unsigned PHYSICAL         = 0x002;
  51 /** The request is an ALPHA VPTE pal access (hw_ld). */
  52 const unsigned VPTE             = 0x004;
  53 /** Use the alternate mode bits in ALPHA. */
  54 const unsigned ALTMODE          = 0x008;
  55 /** The request is to an uncacheable address. */
  56 const unsigned UNCACHEABLE      = 0x010;
  57 /** The request should not cause a page fault. */
  58 const unsigned NO_FAULT         = 0x020;
  59 /** The request should be prefetched into the exclusive state. */
  60 const unsigned PF_EXCLUSIVE     = 0x100;
  61 /** The request should be marked as LRU. */
  62 const unsigned EVICT_NEXT       = 0x200;
  63 /** The request should ignore unaligned access faults */
  64 const unsigned NO_ALIGN_FAULT   = 0x400;
  65
  66 class Request
  67 {
  68   private:
  69     /**
  70      * The physical address of the request. Valid only if validPaddr
  71      * is set. */
  72     Addr paddr;
  73
  74     /**
  75      * The size of the request. This field must be set when vaddr or
  76      * paddr is written via setVirt() or setPhys(), so it is always
  77      * valid as long as one of the address fields is valid.  */
  78     int size;
  79
  80     /** Flag structure for the request. */
  81     uint32_t flags;
  82
  83     /**
  84      * The time this request was started. Used to calculate
  85      * latencies. This field is set to curTick any time paddr or vaddr
  86      * is written.  */
  87     Tick time;
  88
  89     /** The address space ID. */
  90     int asid;
  91     /** The virtual address of the request. */
  92     Addr vaddr;
  93
  94     /** The return value of store conditional. */
  95     uint64_t scResult;
  96
  97     /** The cpu number (for statistics, typically). */
  98     int cpuNum;
  99     /** The requesting thread id (for statistics, typically). */
 100     int  threadNum;
 101
 102     /** program counter of initiating access; for tracing/debugging */
 103     Addr pc;
 104
 105     /** Whether or not paddr is valid (has been written yet). */
 106     bool validPaddr;
 107     /** Whether or not the asid & vaddr are valid. */
 108     bool validAsidVaddr;
 109     /** Whether or not the sc result is valid. */
 110     bool validScResult;
 111     /** Whether or not the cpu number & thread ID are valid. */
 112     bool validCpuAndThreadNums;
 113     /** Whether or not the pc is valid. */
 114     bool validPC;
 115
 116   public:
 117     /** Minimal constructor.  No fields are initialized. */
 118     Request()
 119         : validPaddr(false), validAsidVaddr(false),
 120           validScResult(false), validCpuAndThreadNums(false), validPC(false)
 121     {}
 122
 123     /**
 124      * Constructor for physical (e.g. device) requests.  Initializes
 125      * just physical address, size, flags, and timestamp (to curTick).
 126      * These fields are adequate to perform a request.  */
 127     Request(Addr _paddr, int _size, int _flags)
 128         : validCpuAndThreadNums(false)
 129     { setPhys(_paddr, _size, _flags); }
 130
 131     Request(int _asid, Addr _vaddr, int _size, int _flags, Addr _pc,
 132             int _cpuNum, int _threadNum)
 133     {
 134         setThreadContext(_cpuNum, _threadNum);
 135         setVirt(_asid, _vaddr, _size, _flags, _pc);
 136     }
 137
 138     /**
 139      * Set up CPU and thread numbers. */
 140     void setThreadContext(int _cpuNum, int _threadNum)
 141     {
 142         cpuNum = _cpuNum;
 143         threadNum = _threadNum;
 144         validCpuAndThreadNums = true;
 145     }
 146
 147     /**
 148      * Set up a physical (e.g. device) request in a previously
 149      * allocated Request object. */
 150     void setPhys(Addr _paddr, int _size, int _flags)
 151     {
 152         paddr = _paddr;
 153         size = _size;
 154         flags = _flags;
 155         time = curTick;
 156         validPaddr = true;
 157         validAsidVaddr = false;
 158         validPC = false;
 159         validScResult = false;
 160     }
 161
 162     /**
 163      * Set up a virtual (e.g., CPU) request in a previously
 164      * allocated Request object. */
 165     void setVirt(int _asid, Addr _vaddr, int _size, int _flags, Addr _pc)
 166     {
 167         asid = _asid;
 168         vaddr = _vaddr;
 169         size = _size;
 170         flags = _flags;
 171         pc = _pc;
 172         time = curTick;
 173         validPaddr = false;
 174         validAsidVaddr = true;
 175         validPC = true;
 176         validScResult = false;
 177     }
 178
 179     /** Set just the physical address.  This should only be used to
 180      * record the result of a translation, and thus the vaddr must be
 181      * valid before this method is called.  Otherwise, use setPhys()
 182      * to guarantee that the size and flags are also set.
 183      */
 184     void setPaddr(Addr _paddr)
 185     {
 186         assert(validAsidVaddr);
 187         paddr = _paddr;
 188         validPaddr = true;
 189     }
 190
 191     /** Accessor for paddr. */
 192     Addr getPaddr() { assert(validPaddr); return paddr; }
 193
 194     /** Accessor for size. */
 195     int getSize() { assert(validPaddr || validAsidVaddr); return size; }
 196     /** Accessor for time. */
 197     Tick getTime() { assert(validPaddr || validAsidVaddr); return time; }
 198
 199     /** Accessor for flags. */
 200     uint32_t getFlags() { assert(validPaddr || validAsidVaddr); return flags; }
 201     /** Accessor for paddr. */
 202     void setFlags(uint32_t _flags)
 203     { assert(validPaddr || validAsidVaddr); flags = _flags; }
 204
 205     /** Accessor function for vaddr.*/
 206     Addr getVaddr() { assert(validAsidVaddr); return vaddr; }
 207
 208     /** Accessor function for asid.*/
 209     int getAsid() { assert(validAsidVaddr); return asid; }
 210
 211     /** Accessor function to check if sc result is valid. */
 212     bool scResultValid() { return validScResult; }
 213     /** Accessor function for store conditional return value.*/
 214     uint64_t getScResult() { assert(validScResult); return scResult; }
 215     /** Accessor function for store conditional return value.*/
 216     void setScResult(uint64_t _scResult)
 217     { scResult = _scResult; validScResult = true; }
 218
 219     /** Accessor function for cpu number.*/
 220     int getCpuNum() { assert(validCpuAndThreadNums); return cpuNum; }
 221     /** Accessor function for thread number.*/
 222     int getThreadNum()  { assert(validCpuAndThreadNums); return threadNum; }
 223
 224     /** Accessor function for pc.*/
 225     Addr getPC() { assert(validPC); return pc; }
 226
 227     friend class Packet;
 228 };
 229
 230 #endif // __MEM_REQUEST_HH__