tlb.hh revision 6022 
1/*
2 * Copyright (c) 2001-2005 The Regents of The University of Michigan
3 * Copyright (c) 2007 MIPS Technologies, Inc.
4 * Copyright (c) 2007-2008 The Florida State University
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions are
9 * met: redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer;
11 * redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution;
14 * neither the name of the copyright holders nor the names of its
15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 *
30 * Authors: Nathan Binkert
31 *          Steve Reinhardt
32 *          Stephen Hines
33 */
34
35#ifndef __ARCH_ARM_TLB_HH__
36#define __ARCH_ARM_TLB_HH__
37
38#include <map>
39
40#include "arch/arm/isa_traits.hh"
41#include "arch/arm/utility.hh"
42#include "arch/arm/vtophys.hh"
43#include "arch/arm/pagetable.hh"
44#include "base/statistics.hh"
45#include "mem/request.hh"
46#include "params/ArmDTB.hh"
47#include "params/ArmITB.hh"
48#include "sim/faults.hh"
49#include "sim/tlb.hh"
50
51class ThreadContext;
52
53/* ARM does not distinguish between a DTLB and an ITLB -> unified TLB
54   However, to maintain compatibility with other architectures, we'll
55   simply create an ITLB and DTLB that will point to the real TLB */
56namespace ArmISA {
57
58// WARN: This particular TLB entry is not necessarily conformed to ARM ISA
59struct TlbEntry
60{
61    Addr _pageStart;
62    TlbEntry() {}
63    TlbEntry(Addr asn, Addr vaddr, Addr paddr) : _pageStart(paddr) {}
64
65    void
66    updateVaddr(Addr new_vaddr)
67    {
68        panic("unimplemented");
69    }
70
71    Addr pageStart()
72    {
73        return _pageStart;
74    }
75
76    void serialize(std::ostream &os)
77    {
78        SERIALIZE_SCALAR(_pageStart);
79    }
80
81    void unserialize(Checkpoint *cp, const std::string &section)
82    {
83        UNSERIALIZE_SCALAR(_pageStart);
84    }
85
86};
87
88class TLB : public BaseTLB
89{
90  protected:
91    typedef std::multimap<Addr, int> PageTable;
92    PageTable lookupTable;	// Quick lookup into page table
93
94    ArmISA::PTE *table;	// the Page Table
95    int size;			// TLB Size
96    int nlu;			// not last used entry (for replacement)
97
98    void nextnlu() { if (++nlu >= size) nlu = 0; }
99    ArmISA::PTE *lookup(Addr vpn, uint8_t asn) const;
100
101    mutable Stats::Scalar read_hits;
102    mutable Stats::Scalar read_misses;
103    mutable Stats::Scalar read_acv;
104    mutable Stats::Scalar read_accesses;
105    mutable Stats::Scalar write_hits;
106    mutable Stats::Scalar write_misses;
107    mutable Stats::Scalar write_acv;
108    mutable Stats::Scalar write_accesses;
109    Stats::Formula hits;
110    Stats::Formula misses;
111    Stats::Formula invalids;
112    Stats::Formula accesses;
113
114  public:
115    typedef ArmTLBParams Params;
116    TLB(const Params *p);
117
118    int probeEntry(Addr vpn,uint8_t) const;
119    ArmISA::PTE *getEntry(unsigned) const;
120    virtual ~TLB();
121    int smallPages;
122    int getsize() const { return size; }
123
124    ArmISA::PTE &index(bool advance = true);
125    void insert(Addr vaddr, ArmISA::PTE &pte);
126    void insertAt(ArmISA::PTE &pte, unsigned Index, int _smallPages);
127    void flushAll();
128    void demapPage(Addr vaddr, uint64_t asn)
129    {
130        panic("demapPage unimplemented.\n");
131    }
132
133    // static helper functions... really
134    static bool validVirtualAddress(Addr vaddr);
135
136    static Fault checkCacheability(RequestPtr &req);
137
138    // Checkpointing
139    void serialize(std::ostream &os);
140    void unserialize(Checkpoint *cp, const std::string &section);
141
142    void regStats();
143};
144
145class ITB : public TLB
146{
147  public:
148    typedef ArmTLBParams Params;
149    ITB(const Params *p);
150
151    Fault translateAtomic(RequestPtr req, ThreadContext *tc);
152    void translateTiming(RequestPtr req, ThreadContext *tc,
153            Translation *translation);
154};
155
156class DTB : public TLB
157{
158  public:
159    typedef ArmTLBParams Params;
160    DTB(const Params *p);
161
162    Fault translateAtomic(RequestPtr req, ThreadContext *tc, bool write);
163    void translateTiming(RequestPtr req, ThreadContext *tc,
164            Translation *translation, bool write);
165};
166
167class UTB : public ITB, public DTB
168{
169  public:
170    typedef ArmTLBParams Params;
171    UTB(const Params *p);
172
173};
174
175}
176
177#endif // __ARCH_ARM_TLB_HH__
178