pagetable_walker.hh revision 5897:29cecf4fe602 
1/*
2 * Copyright (c) 2007 The Hewlett-Packard Development Company
3 * All rights reserved.
4 *
5 * Redistribution and use of this software in source and binary forms,
6 * with or without modification, are permitted provided that the
7 * following conditions are met:
8 *
9 * The software must be used only for Non-Commercial Use which means any
10 * use which is NOT directed to receiving any direct monetary
11 * compensation for, or commercial advantage from such use.  Illustrative
12 * examples of non-commercial use are academic research, personal study,
13 * teaching, education and corporate research & development.
14 * Illustrative examples of commercial use are distributing products for
15 * commercial advantage and providing services using the software for
16 * commercial advantage.
17 *
18 * If you wish to use this software or functionality therein that may be
19 * covered by patents for commercial use, please contact:
20 *     Director of Intellectual Property Licensing
21 *     Office of Strategy and Technology
22 *     Hewlett-Packard Company
23 *     1501 Page Mill Road
24 *     Palo Alto, California  94304
25 *
26 * Redistributions of source code must retain the above copyright notice,
27 * this list of conditions and the following disclaimer.  Redistributions
28 * in binary form must reproduce the above copyright notice, this list of
29 * conditions and the following disclaimer in the documentation and/or
30 * other materials provided with the distribution.  Neither the name of
31 * the COPYRIGHT HOLDER(s), HEWLETT-PACKARD COMPANY, nor the names of its
32 * contributors may be used to endorse or promote products derived from
33 * this software without specific prior written permission.  No right of
34 * sublicense is granted herewith.  Derivatives of the software and
35 * output created using the software may be prepared, but only for
36 * Non-Commercial Uses.  Derivatives of the software may be shared with
37 * others provided: (i) the others agree to abide by the list of
38 * conditions herein which includes the Non-Commercial Use restrictions;
39 * and (ii) such Derivatives of the software include the above copyright
40 * notice to acknowledge the contribution from this software where
41 * applicable, this list of conditions and the disclaimer below.
42 *
43 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
44 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
45 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
46 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
47 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
48 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
49 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
50 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
51 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
52 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
53 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
54 *
55 * Authors: Gabe Black
56 */
57
58#ifndef __ARCH_X86_PAGE_TABLE_WALKER_HH__
59#define __ARCH_X86_PAGE_TABLE_WALKER_HH__
60
61#include <vector>
62
63#include "arch/x86/pagetable.hh"
64#include "arch/x86/tlb.hh"
65#include "mem/mem_object.hh"
66#include "mem/packet.hh"
67#include "params/X86PagetableWalker.hh"
68#include "sim/host.hh"
69
70class ThreadContext;
71
72namespace X86ISA
73{
74    class Walker : public MemObject
75    {
76      public:
77        enum State {
78            Ready,
79            Waiting,
80            // Long mode
81            LongPML4, LongPDP, LongPD, LongPTE,
82            // PAE legacy mode
83            PAEPDP, PAEPD, PAEPTE,
84            // Non PAE legacy mode with and without PSE
85            PSEPD, PD, PTE
86        };
87
88        // Act on the current state and determine what to do next. The global
89        // read should be the packet that just came back from a read and write
90        // should be NULL. When the function returns, read is either NULL
91        // if the machine is finished, or points to a packet to initiate
92        // the next read. If any write is required to update an "accessed"
93        // bit, write will point to a packet to do the write. Otherwise it
94        // will be NULL. The return value is whatever fault was incurred
95        // during this stage of the lookup.
96        Fault doNext(PacketPtr &write);
97
98        // Kick off the state machine.
99        Fault start(ThreadContext * _tc, BaseTLB::Translation *translation,
100                RequestPtr req, bool write, bool execute);
101        // Clean up after the state machine.
102        void
103        stop()
104        {
105            nextState = Ready;
106            delete read->req;
107            delete read;
108            read = NULL;
109        }
110
111      protected:
112
113        /*
114         * State having to do with sending packets.
115         */
116        PacketPtr read;
117        std::vector<PacketPtr> writes;
118
119        // How many memory operations are in flight.
120        unsigned inflight;
121
122        bool retrying;
123
124        /*
125         * The fault, if any, that's waiting to be delivered in timing mode.
126         */
127        Fault timingFault;
128
129        /*
130         * Functions for dealing with packets.
131         */
132        bool recvTiming(PacketPtr pkt);
133        void recvRetry();
134
135        void sendPackets();
136
137        /*
138         * Port for accessing memory
139         */
140        class WalkerPort : public Port
141        {
142          public:
143            WalkerPort(const std::string &_name, Walker * _walker) :
144                  Port(_name, _walker), walker(_walker),
145                  snoopRangeSent(false)
146            {}
147
148          protected:
149            Walker * walker;
150
151            bool snoopRangeSent;
152
153            bool recvTiming(PacketPtr pkt);
154            Tick recvAtomic(PacketPtr pkt);
155            void recvFunctional(PacketPtr pkt);
156            void recvStatusChange(Status status);
157            void recvRetry();
158            void getDeviceAddressRanges(AddrRangeList &resp,
159                    bool &snoop)
160            {
161                resp.clear();
162                snoop = true;
163            }
164        };
165
166        Port *getPort(const std::string &if_name, int idx = -1);
167
168        friend class WalkerPort;
169
170        WalkerPort port;
171
172        // The TLB we're supposed to load.
173        TLB * tlb;
174        System * sys;
175        BaseTLB::Translation * translation;
176
177        /*
178         * State machine state.
179         */
180        ThreadContext * tc;
181        RequestPtr req;
182        State state;
183        State nextState;
184        int size;
185        bool enableNX;
186        bool write, execute, user;
187        TlbEntry entry;
188
189        Fault pageFault(bool present);
190
191      public:
192
193        void setTLB(TLB * _tlb)
194        {
195            tlb = _tlb;
196        }
197
198        typedef X86PagetableWalkerParams Params;
199
200        Walker(const Params *params) :
201            MemObject(params),
202            read(NULL), inflight(0), retrying(false),
203            port(name() + ".port", this),
204            tlb(NULL), sys(params->system),
205            tc(NULL), state(Ready), nextState(Ready)
206        {
207        }
208    };
209}
210#endif // __ARCH_X86_PAGE_TABLE_WALKER_HH__
211