src/arch/x86/pagetable_walker.hh

   1 /*
   2  * Copyright (c) 2007 The Hewlett-Packard Development Company
   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  * Redistribution and use in source and binary forms, with or without
  15  * modification, are permitted provided that the following conditions are
  16  * met: redistributions of source code must retain the above copyright
  17  * notice, this list of conditions and the following disclaimer;
  18  * redistributions in binary form must reproduce the above copyright
  19  * notice, this list of conditions and the following disclaimer in the
  20  * documentation and/or other materials provided with the distribution;
  21  * neither the name of the copyright holders nor the names of its
  22  * contributors may be used to endorse or promote products derived from
  23  * this software without specific prior written permission.
  24  *
  25  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  26  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  27  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  28  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  29  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  30  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  31  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  32  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  33  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  34  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  35  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  36  *
  37  * Authors: Gabe Black
  38  */
  39
  40 #ifndef __ARCH_X86_PAGE_TABLE_WALKER_HH__
  41 #define __ARCH_X86_PAGE_TABLE_WALKER_HH__
  42
  43 #include <vector>
  44
  45 #include "arch/x86/pagetable.hh"
  46 #include "arch/x86/tlb.hh"
  47 #include "base/types.hh"
  48 #include "base/fast_alloc.hh"
  49 #include "mem/mem_object.hh"
  50 #include "mem/packet.hh"
  51 #include "params/X86PagetableWalker.hh"
  52 #include "sim/faults.hh"
  53
  54 class ThreadContext;
  55
  56 namespace X86ISA
  57 {
  58     class Walker : public MemObject
  59     {
  60       protected:
  61         // Port for accessing memory
  62         class WalkerPort : public Port
  63         {
  64           public:
  65             WalkerPort(const std::string &_name, Walker * _walker) :
  66                   Port(_name, _walker), walker(_walker),
  67                   snoopRangeSent(false)
  68             {}
  69
  70           protected:
  71             Walker * walker;
  72
  73             bool snoopRangeSent;
  74
  75             bool recvTiming(PacketPtr pkt);
  76             Tick recvAtomic(PacketPtr pkt);
  77             void recvFunctional(PacketPtr pkt);
  78             void recvStatusChange(Status status);
  79             void recvRetry();
  80             void getDeviceAddressRanges(AddrRangeList &resp,
  81                     bool &snoop)
  82             {
  83                 resp.clear();
  84                 snoop = true;
  85             }
  86         };
  87
  88         friend class WalkerPort;
  89         WalkerPort port;
  90         Port *getPort(const std::string &if_name, int idx = -1);
  91
  92         // State to track each walk of the page table
  93         class WalkerState : public FastAlloc
  94         {
  95           private:
  96             enum State {
  97                 Ready,
  98                 Waiting,
  99                 // Long mode
 100                 LongPML4, LongPDP, LongPD, LongPTE,
 101                 // PAE legacy mode
 102                 PAEPDP, PAEPD, PAEPTE,
 103                 // Non PAE legacy mode with and without PSE
 104                 PSEPD, PD, PTE
 105             };
 106
 107           protected:
 108             Walker * walker;
 109             ThreadContext *tc;
 110             RequestPtr req;
 111             State state;
 112             State nextState;
 113             int dataSize;
 114             bool enableNX;
 115             unsigned inflight;
 116             TlbEntry entry;
 117             PacketPtr read;
 118             std::vector<PacketPtr> writes;
 119             Fault timingFault;
 120             TLB::Translation * translation;
 121             BaseTLB::Mode mode;
 122             bool functional;
 123             bool timing;
 124             bool retrying;
 125             bool started;
 126
 127           public:
 128             WalkerState(Walker * _walker, BaseTLB::Translation *_translation,
 129                     RequestPtr _req, bool _isFunctional = false) :
 130                         walker(_walker), req(_req), state(Ready),
 131                         nextState(Ready), inflight(0),
 132                         translation(_translation),
 133                         functional(_isFunctional), timing(false),
 134                         retrying(false), started(false)
 135             {
 136             }
 137             void initState(ThreadContext * _tc, BaseTLB::Mode _mode,
 138                            bool _isTiming = false);
 139             Fault startWalk();
 140             Fault startFunctional(Addr &addr, Addr &pageSize);
 141             bool recvPacket(PacketPtr pkt);
 142             bool isRetrying();
 143             bool wasStarted();
 144             bool isTiming();
 145             void retry();
 146             std::string name() const {return walker->name();}
 147
 148           private:
 149             void setupWalk(Addr vaddr);
 150             Fault stepWalk(PacketPtr &write);
 151             void sendPackets();
 152             void endWalk();
 153             Fault pageFault(bool present);
 154         };
 155
 156         friend class WalkerState;
 157         // State for timing and atomic accesses (need multiple per walker in
 158         // the case of multiple outstanding requests in timing mode)
 159         std::list<WalkerState *> currStates;
 160         // State for functional accesses (only need one of these per walker)
 161         WalkerState funcState;
 162
 163         struct WalkerSenderState : public Packet::SenderState
 164         {
 165             WalkerState * senderWalk;
 166             Packet::SenderState * saved;
 167             WalkerSenderState(WalkerState * _senderWalk,
 168                     Packet::SenderState * _saved) :
 169                 senderWalk(_senderWalk), saved(_saved) {}
 170         };
 171
 172       public:
 173         // Kick off the state machine.
 174         Fault start(ThreadContext * _tc, BaseTLB::Translation *translation,
 175                 RequestPtr req, BaseTLB::Mode mode);
 176         Fault startFunctional(ThreadContext * _tc, Addr &addr,
 177                 Addr &pageSize, BaseTLB::Mode mode);
 178
 179       protected:
 180         // The TLB we're supposed to load.
 181         TLB * tlb;
 182         System * sys;
 183
 184         // Functions for dealing with packets.
 185         bool recvTiming(PacketPtr pkt);
 186         void recvRetry();
 187         bool sendTiming(WalkerState * sendingState, PacketPtr pkt);
 188
 189       public:
 190
 191         void setTLB(TLB * _tlb)
 192         {
 193             tlb = _tlb;
 194         }
 195
 196         typedef X86PagetableWalkerParams Params;
 197
 198         Walker(const Params *params) :
 199             MemObject(params), port(name() + ".port", this),
 200             funcState(this, NULL, NULL, true), tlb(NULL), sys(params->system)
 201         {
 202         }
 203     };
 204 }
 205 #endif // __ARCH_X86_PAGE_TABLE_WALKER_HH__