1/*
2 * Copyright (c) 2014 Advanced Micro Devices, Inc.
3 * Copyright (c) 2003 The Regents of The University of Michigan
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: Steve Reinhardt
30 */
31
32/**
33 * @file
34 * Declarations of a non-full system Page Table.
35 */
36
37#ifndef __MEM_PAGE_TABLE_HH__
38#define __MEM_PAGE_TABLE_HH__
39
40#include <string>
41#include <unordered_map>
42
43#include "base/intmath.hh"
44#include "base/types.hh"
45#include "mem/request.hh"
46#include "sim/serialize.hh"
47
48class ThreadContext;
49
50class EmulationPageTable : public Serializable
51{
52  public:
53    struct Entry
54    {
55        Addr paddr;
56        uint64_t flags;
57
58        Entry(Addr paddr, uint64_t flags) : paddr(paddr), flags(flags) {}
59        Entry() {}
60    };
61
62  protected:
63    typedef std::unordered_map<Addr, Entry> PTable;
64    typedef PTable::iterator PTableItr;
65    PTable pTable;
66
67    const Addr pageSize;
68    const Addr offsetMask;
69
70    const uint64_t _pid;
71    const std::string _name;
72
73  public:
74
75    EmulationPageTable(
76            const std::string &__name, uint64_t _pid, Addr _pageSize) :
77            pageSize(_pageSize), offsetMask(mask(floorLog2(_pageSize))),
78            _pid(_pid), _name(__name), shared(false)
79    {
80        assert(isPowerOf2(pageSize));
81    }
82
83    uint64_t pid() const { return _pid; };
84
85    virtual ~EmulationPageTable() {};
86
87    /* generic page table mapping flags
88     *              unset | set
89     * bit 0 - no-clobber | clobber
90     * bit 2 - cacheable  | uncacheable
91     * bit 3 - read-write | read-only
92     */
93    enum MappingFlags : uint32_t {
94        Clobber     = 1,
95        Uncacheable = 4,
96        ReadOnly    = 8,
97    };
98
99    // flag which marks the page table as shared among software threads
100    bool shared;
101
102    virtual void initState() {};
103
104    // for DPRINTF compatibility
105    const std::string name() const { return _name; }
106
107    Addr pageAlign(Addr a)  { return (a & ~offsetMask); }
108    Addr pageOffset(Addr a) { return (a &  offsetMask); }
109
110    /**
111     * Maps a virtual memory region to a physical memory region.
112     * @param vaddr The starting virtual address of the region.
113     * @param paddr The starting physical address where the region is mapped.
114     * @param size The length of the region.
115     * @param flags Generic mapping flags that can be set by or-ing values
116     *              from MappingFlags enum.
117     */
118    virtual void map(Addr vaddr, Addr paddr, int64_t size, uint64_t flags = 0);
119    virtual void remap(Addr vaddr, int64_t size, Addr new_vaddr);
120    virtual void unmap(Addr vaddr, int64_t size);
121
122    /**
123     * Check if any pages in a region are already allocated
124     * @param vaddr The starting virtual address of the region.
125     * @param size The length of the region.
126     * @return True if no pages in the region are mapped.
127     */
128    virtual bool isUnmapped(Addr vaddr, int64_t size);
129
130    /**
131     * Lookup function
132     * @param vaddr The virtual address.
133     * @return The page table entry corresponding to vaddr.
134     */
135    const Entry *lookup(Addr vaddr);
136
137    /**
138     * Translate function
139     * @param vaddr The virtual address.
140     * @param paddr Physical address from translation.
141     * @return True if translation exists
142     */
143    bool translate(Addr vaddr, Addr &paddr);
144
145    /**
146     * Simplified translate function (just check for translation)
147     * @param vaddr The virtual address.
148     * @return True if translation exists
149     */
150    bool translate(Addr vaddr) { Addr dummy; return translate(vaddr, dummy); }
151
152    /**
153     * Perform a translation on the memory request, fills in paddr
154     * field of req.
155     * @param req The memory request.
156     */
157    Fault translate(const RequestPtr &req);
158
159    void getMappings(std::vector<std::pair<Addr, Addr>> *addr_mappings);
160
161    void serialize(CheckpointOut &cp) const override;
162    void unserialize(CheckpointIn &cp) override;
163};
164
165#endif // __MEM_PAGE_TABLE_HH__
166