summaryrefslogtreecommitdiff
path: root/src/arch/x86/pagetable_walker.hh
blob: 992711acdd0fdc87b5223fd1064a44b6fc560579 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
/*
 * Copyright (c) 2007 The Hewlett-Packard Development Company
 * All rights reserved.
 *
 * Redistribution and use of this software in source and binary forms,
 * with or without modification, are permitted provided that the
 * following conditions are met:
 *
 * The software must be used only for Non-Commercial Use which means any
 * use which is NOT directed to receiving any direct monetary
 * compensation for, or commercial advantage from such use.  Illustrative
 * examples of non-commercial use are academic research, personal study,
 * teaching, education and corporate research & development.
 * Illustrative examples of commercial use are distributing products for
 * commercial advantage and providing services using the software for
 * commercial advantage.
 *
 * If you wish to use this software or functionality therein that may be
 * covered by patents for commercial use, please contact:
 *     Director of Intellectual Property Licensing
 *     Office of Strategy and Technology
 *     Hewlett-Packard Company
 *     1501 Page Mill Road
 *     Palo Alto, California  94304
 *
 * Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.  Redistributions
 * in binary form must reproduce the above copyright notice, this list of
 * conditions and the following disclaimer in the documentation and/or
 * other materials provided with the distribution.  Neither the name of
 * the COPYRIGHT HOLDER(s), HEWLETT-PACKARD COMPANY, nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.  No right of
 * sublicense is granted herewith.  Derivatives of the software and
 * output created using the software may be prepared, but only for
 * Non-Commercial Uses.  Derivatives of the software may be shared with
 * others provided: (i) the others agree to abide by the list of
 * conditions herein which includes the Non-Commercial Use restrictions;
 * and (ii) such Derivatives of the software include the above copyright
 * notice to acknowledge the contribution from this software where
 * applicable, this list of conditions and the disclaimer below.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Authors: Gabe Black
 */

#ifndef __ARCH_X86_PAGE_TABLE_WALKER_HH__
#define __ARCH_X86_PAGE_TABLE_WALKER_HH__

#include <vector>

#include "arch/x86/pagetable.hh"
#include "arch/x86/tlb.hh"
#include "mem/mem_object.hh"
#include "mem/packet.hh"
#include "params/X86PagetableWalker.hh"
#include "sim/host.hh"

class ThreadContext;

namespace X86ISA
{
    class Walker : public MemObject
    {
      public:
        enum State {
            Ready,
            Waiting,
            // Long mode
            LongPML4, LongPDP, LongPD, LongPTE,
            // PAE legacy mode
            PAEPDP, PAEPD, PAEPTE,
            // Non PAE legacy mode with and without PSE
            PSEPD, PD, PTE
        };

        // Act on the current state and determine what to do next. read
        // should be the packet that just came back from a read and write
        // should be NULL. When the function returns, read is either NULL
        // if the machine is finished, or points to a packet to initiate
        // the next read. If any write is required to update an "accessed"
        // bit, write will point to a packet to do the write. Otherwise it
        // will be NULL. The return value is whatever fault was incurred
        // during this stage of the lookup.
        Fault doNext(PacketPtr &read, PacketPtr &write);

        // Kick off the state machine.
        Fault start(ThreadContext * _tc, BaseTLB::Translation *translation,
                RequestPtr req, bool write, bool execute);
        // Clean up after the state machine.
        void
        stop()
        {
            nextState = Ready;
            delete read->req;
            delete read;
            read = NULL;
        }

      protected:

        /*
         * State having to do with sending packets.
         */
        PacketPtr read;
        std::vector<PacketPtr> writes;

        // How many memory operations are in flight.
        unsigned inflight;

        bool retrying;

        /*
         * The fault, if any, that's waiting to be delivered in timing mode.
         */
        Fault timingFault;

        /*
         * Functions for dealing with packets.
         */
        bool recvTiming(PacketPtr pkt);
        void recvRetry();

        void sendPackets();

        /*
         * Port for accessing memory
         */
        class WalkerPort : public Port
        {
          public:
            WalkerPort(const std::string &_name, Walker * _walker) :
                  Port(_name, _walker), walker(_walker),
                  snoopRangeSent(false)
            {}

          protected:
            Walker * walker;

            bool snoopRangeSent;

            bool recvTiming(PacketPtr pkt);
            Tick recvAtomic(PacketPtr pkt);
            void recvFunctional(PacketPtr pkt);
            void recvStatusChange(Status status);
            void recvRetry();
            void getDeviceAddressRanges(AddrRangeList &resp,
                    bool &snoop)
            {
                resp.clear();
                snoop = true;
            }
        };

        Port *getPort(const std::string &if_name, int idx = -1);

        friend class WalkerPort;

        WalkerPort port;

        // The TLB we're supposed to load.
        TLB * tlb;
        System * sys;
        BaseTLB::Translation * translation;

        /*
         * State machine state.
         */
        ThreadContext * tc;
        RequestPtr req;
        State state;
        State nextState;
        int size;
        bool enableNX;
        bool write, execute, user;
        TlbEntry entry;
        
        Fault pageFault(bool present);

      public:

        void setTLB(TLB * _tlb)
        {
            tlb = _tlb;
        }

        typedef X86PagetableWalkerParams Params;

        Walker(const Params *params) :
            MemObject(params),
            read(NULL), inflight(0), retrying(false),
            port(name() + ".port", this),
            tlb(NULL), sys(params->system),
            tc(NULL), state(Ready), nextState(Ready)
        {
        }
    };
}
#endif // __ARCH_X86_PAGE_TABLE_WALKER_HH__