pagetable.hh revision 5268:5bfc53fe60e7 
1/*
2 * Copyright (c) 2002-2005 The Regents of The University of Michigan
3 * Copyright (c) 2007 MIPS Technologies, Inc.
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are
8 * met: redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer;
10 * redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution;
13 * neither the name of the copyright holders nor the names of its
14 * contributors may be used to endorse or promote products derived from
15 * this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
18 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
19 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
20 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
21 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
22 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
23 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
27 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 *
29 * Authors: Nathan Binkert
30 *          Steve Reinhardt
31 *          Jaidev Patwardhan
32 */
33
34#ifndef __ARCH_MIPS_PAGETABLE_H__
35#define __ARCH_MIPS_PAGETABLE_H__
36
37#include "arch/mips/isa_traits.hh"
38#include "arch/mips/utility.hh"
39#include "arch/mips/vtophys.hh"
40#include "config/full_system.hh"
41
42namespace MipsISA {
43
44    struct VAddr
45    {
46        static const int ImplBits = 43;
47        static const Addr ImplMask = (ULL(1) << ImplBits) - 1;
48        static const Addr UnImplMask = ~ImplMask;
49
50        VAddr(Addr a) : addr(a) {}
51        Addr addr;
52        operator Addr() const { return addr; }
53        const VAddr &operator=(Addr a) { addr = a; return *this; }
54
55        Addr vpn() const { return (addr & ImplMask) >> PageShift; }
56        Addr page() const { return addr & Page_Mask; }
57        Addr offset() const { return addr & PageOffset; }
58
59        Addr level3() const
60        { return MipsISA::PteAddr(addr >> PageShift); }
61        Addr level2() const
62        { return MipsISA::PteAddr(addr >> NPtePageShift + PageShift); }
63        Addr level1() const
64        { return MipsISA::PteAddr(addr >> 2 * NPtePageShift + PageShift); }
65    };
66
67    // ITB/DTB page table entry
68    struct PTE
69    {
70      Addr Mask; // What parts of the VAddr (from bits 28..11) should be used in translation (includes Mask and MaskX from PageMask)
71      Addr VPN; // Virtual Page Number (/2) (Includes VPN2 + VPN2X .. bits 31..11 from EntryHi)
72      uint8_t asid; // Address Space ID (8 bits) // Lower 8 bits of EntryHi
73
74      bool G;    // Global Bit - Obtained by an *AND* of EntryLo0 and EntryLo1 G bit
75
76      /* Contents of Entry Lo0 */
77      Addr PFN0; // Physical Frame Number - Even
78      bool D0;   // Even entry Dirty Bit
79      bool V0;   // Even entry Valid Bit
80      uint8_t C0; // Cache Coherency Bits - Even
81
82      /* Contents of Entry Lo1 */
83      Addr PFN1; // Physical Frame Number - Odd
84      bool D1;   // Odd entry Dirty Bit
85      bool V1;   // Odd entry Valid Bit
86      uint8_t C1; // Cache Coherency Bits (3 bits)
87
88      /* The next few variables are put in as optimizations to reduce TLB lookup overheads */
89      /* For a given Mask, what is the address shift amount, and what is the OffsetMask */
90      int AddrShiftAmount;
91      int OffsetMask;
92
93      bool Valid() { return (V0 | V1);};
94        void serialize(std::ostream &os);
95        void unserialize(Checkpoint *cp, const std::string &section);
96    };
97
98};
99#endif // __ARCH_MIPS_PAGETABLE_H__
100
101