pagetable_walker.hh revision 9044 
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 "mem/mem_object.hh"
49#include "mem/packet.hh"
50#include "params/X86PagetableWalker.hh"
51#include "sim/faults.hh"
52#include "sim/system.hh"
53
54class ThreadContext;
55
56namespace X86ISA
57{
58    class Walker : public MemObject
59    {
60      protected:
61        // Port for accessing memory
62        class WalkerPort : public MasterPort
63        {
64          public:
65            WalkerPort(const std::string &_name, Walker * _walker) :
66                  MasterPort(_name, _walker), walker(_walker)
67            {}
68
69          protected:
70            Walker *walker;
71
72            bool recvTimingResp(PacketPtr pkt);
73
74            /**
75             * Snooping a coherence request, do nothing.
76             */
77            void recvTimingSnoopReq(PacketPtr pkt) { }
78            Tick recvAtomicSnoop(PacketPtr pkt) { return 0; }
79            void recvFunctionalSnoop(PacketPtr pkt) { }
80            void recvRetry();
81            bool isSnooping() const { return true; }
82        };
83
84        friend class WalkerPort;
85        WalkerPort port;
86
87        // State to track each walk of the page table
88        class WalkerState
89        {
90          private:
91            enum State {
92                Ready,
93                Waiting,
94                // Long mode
95                LongPML4, LongPDP, LongPD, LongPTE,
96                // PAE legacy mode
97                PAEPDP, PAEPD, PAEPTE,
98                // Non PAE legacy mode with and without PSE
99                PSEPD, PD, PTE
100            };
101
102          protected:
103            Walker *walker;
104            ThreadContext *tc;
105            RequestPtr req;
106            State state;
107            State nextState;
108            int dataSize;
109            bool enableNX;
110            unsigned inflight;
111            TlbEntry entry;
112            PacketPtr read;
113            std::vector<PacketPtr> writes;
114            Fault timingFault;
115            TLB::Translation * translation;
116            BaseTLB::Mode mode;
117            bool functional;
118            bool timing;
119            bool retrying;
120            bool started;
121          public:
122            WalkerState(Walker * _walker, BaseTLB::Translation *_translation,
123                    RequestPtr _req, bool _isFunctional = false) :
124                        walker(_walker), req(_req), state(Ready),
125                        nextState(Ready), inflight(0),
126                        translation(_translation),
127                        functional(_isFunctional), timing(false),
128                        retrying(false), started(false)
129            {
130            }
131            void initState(ThreadContext * _tc, BaseTLB::Mode _mode,
132                           bool _isTiming = false);
133            Fault startWalk();
134            Fault startFunctional(Addr &addr, unsigned &logBytes);
135            bool recvPacket(PacketPtr pkt);
136            bool isRetrying();
137            bool wasStarted();
138            bool isTiming();
139            void retry();
140            std::string name() const {return walker->name();}
141
142          private:
143            void setupWalk(Addr vaddr);
144            Fault stepWalk(PacketPtr &write);
145            void sendPackets();
146            void endWalk();
147            Fault pageFault(bool present);
148        };
149
150        friend class WalkerState;
151        // State for timing and atomic accesses (need multiple per walker in
152        // the case of multiple outstanding requests in timing mode)
153        std::list<WalkerState *> currStates;
154        // State for functional accesses (only need one of these per walker)
155        WalkerState funcState;
156
157        struct WalkerSenderState : public Packet::SenderState
158        {
159            WalkerState * senderWalk;
160            Packet::SenderState * saved;
161            WalkerSenderState(WalkerState * _senderWalk,
162                    Packet::SenderState * _saved) :
163                senderWalk(_senderWalk), saved(_saved) {}
164        };
165
166      public:
167        // Kick off the state machine.
168        Fault start(ThreadContext * _tc, BaseTLB::Translation *translation,
169                RequestPtr req, BaseTLB::Mode mode);
170        Fault startFunctional(ThreadContext * _tc, Addr &addr,
171                unsigned &logBytes, BaseTLB::Mode mode);
172        MasterPort &getMasterPort(const std::string &if_name, int idx = -1);
173
174      protected:
175        // The TLB we're supposed to load.
176        TLB * tlb;
177        System * sys;
178        MasterID masterId;
179
180        // Functions for dealing with packets.
181        bool recvTimingResp(PacketPtr pkt);
182        void recvRetry();
183        bool sendTiming(WalkerState * sendingState, PacketPtr pkt);
184
185      public:
186
187        void setTLB(TLB * _tlb)
188        {
189            tlb = _tlb;
190        }
191
192        typedef X86PagetableWalkerParams Params;
193
194        const Params *
195        params() const
196        {
197            return static_cast<const Params *>(_params);
198        }
199
200        Walker(const Params *params) :
201            MemObject(params), port(name() + ".port", this),
202            funcState(this, NULL, NULL, true), tlb(NULL), sys(params->system),
203            masterId(sys->getMasterId(name()))
204        {
205        }
206    };
207}
208#endif // __ARCH_X86_PAGE_TABLE_WALKER_HH__
209