src/mem/physical.hh

   1 /*
   2  * Copyright (c) 2001-2005 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  */
  30
  31 /* @file
  32  */
  33
  34 #ifndef __PHYSICAL_MEMORY_HH__
  35 #define __PHYSICAL_MEMORY_HH__
  36
  37 #include <map>
  38 #include <string>
  39
  40 #include "base/range.hh"
  41 #include "mem/mem_object.hh"
  42 #include "mem/packet.hh"
  43 #include "mem/tport.hh"
  44 #include "params/PhysicalMemory.hh"
  45 #include "sim/eventq.hh"
  46
  47 //
  48 // Functional model for a contiguous block of physical memory. (i.e. RAM)
  49 //
  50 class PhysicalMemory : public MemObject
  51 {
  52     class MemoryPort : public SimpleTimingPort
  53     {
  54         PhysicalMemory *memory;
  55
  56       public:
  57
  58         MemoryPort(const std::string &_name, PhysicalMemory *_memory);
  59
  60       protected:
  61
  62         virtual Tick recvAtomic(PacketPtr pkt);
  63
  64         virtual void recvFunctional(PacketPtr pkt);
  65
  66         virtual void recvStatusChange(Status status);
  67
  68         virtual void getDeviceAddressRanges(AddrRangeList &resp,
  69                                             bool &snoop);
  70
  71         virtual int deviceBlockSize();
  72     };
  73
  74     int numPorts;
  75
  76
  77   private:
  78     // prevent copying of a MainMemory object
  79     PhysicalMemory(const PhysicalMemory &specmem);
  80     const PhysicalMemory &operator=(const PhysicalMemory &specmem);
  81
  82   protected:
  83
  84     class LockedAddr {
  85       public:
  86         // on alpha, minimum LL/SC granularity is 16 bytes, so lower
  87         // bits need to masked off.
  88         static const Addr Addr_Mask = 0xf;
  89
  90         static Addr mask(Addr paddr) { return (paddr & ~Addr_Mask); }
  91
  92         Addr addr;      // locked address
  93         int cpuNum;     // locking CPU
  94         int threadNum;  // locking thread ID within CPU
  95
  96         // check for matching execution context
  97         bool matchesContext(Request *req)
  98         {
  99             return (cpuNum == req->getCpuNum() &&
 100                     threadNum == req->getThreadNum());
 101         }
 102
 103         LockedAddr(Request *req)
 104             : addr(mask(req->getPaddr())),
 105               cpuNum(req->getCpuNum()),
 106               threadNum(req->getThreadNum())
 107         {
 108         }
 109     };
 110
 111     std::list<LockedAddr> lockedAddrList;
 112
 113     // helper function for checkLockedAddrs(): we really want to
 114     // inline a quick check for an empty locked addr list (hopefully
 115     // the common case), and do the full list search (if necessary) in
 116     // this out-of-line function
 117     bool checkLockedAddrList(PacketPtr pkt);
 118
 119     // Record the address of a load-locked operation so that we can
 120     // clear the execution context's lock flag if a matching store is
 121     // performed
 122     void trackLoadLocked(PacketPtr pkt);
 123
 124     // Compare a store address with any locked addresses so we can
 125     // clear the lock flag appropriately.  Return value set to 'false'
 126     // if store operation should be suppressed (because it was a
 127     // conditional store and the address was no longer locked by the
 128     // requesting execution context), 'true' otherwise.  Note that
 129     // this method must be called on *all* stores since even
 130     // non-conditional stores must clear any matching lock addresses.
 131     bool writeOK(PacketPtr pkt) {
 132         Request *req = pkt->req;
 133         if (lockedAddrList.empty()) {
 134             // no locked addrs: nothing to check, store_conditional fails
 135             bool isLocked = pkt->isLocked();
 136             if (isLocked) {
 137                 req->setExtraData(0);
 138             }
 139             return !isLocked; // only do write if not an sc
 140         } else {
 141             // iterate over list...
 142             return checkLockedAddrList(pkt);
 143         }
 144     }
 145
 146     uint8_t *pmemAddr;
 147     int pagePtr;
 148     Tick lat;
 149     std::vector<MemoryPort*> ports;
 150     typedef std::vector<MemoryPort*>::iterator PortIterator;
 151
 152     uint64_t cachedSize;
 153     uint64_t cachedStart;
 154   public:
 155     Addr new_page();
 156     uint64_t size() { return cachedSize; }
 157     uint64_t start() { return cachedStart; }
 158
 159   public:
 160     typedef PhysicalMemoryParams Params;
 161     PhysicalMemory(const Params *p);
 162     virtual ~PhysicalMemory();
 163
 164     const Params *
 165     params() const
 166     {
 167         return dynamic_cast<const Params *>(_params);
 168     }
 169
 170   public:
 171     int deviceBlockSize();
 172     void getAddressRanges(AddrRangeList &resp, bool &snoop);
 173     virtual Port *getPort(const std::string &if_name, int idx = -1);
 174     void virtual init();
 175     unsigned int drain(Event *de);
 176
 177   protected:
 178     Tick doAtomicAccess(PacketPtr pkt);
 179     void doFunctionalAccess(PacketPtr pkt);
 180     virtual Tick calculateLatency(PacketPtr pkt);
 181     void recvStatusChange(Port::Status status);
 182
 183   public:
 184     virtual void serialize(std::ostream &os);
 185     virtual void unserialize(Checkpoint *cp, const std::string &section);
 186
 187 };
 188
 189 #endif //__PHYSICAL_MEMORY_HH__