summaryrefslogtreecommitdiff
path: root/src/cpu/kvm/arm_cpu.hh
blob: 687cb48b1d4655d153a96ae38221e7681bbb7571 (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
/*
 * Copyright (c) 2012 ARM Limited
 * All rights reserved
 *
 * The license below extends only to copyright in the software and shall
 * not be construed as granting a license to any other intellectual
 * property including but not limited to intellectual property relating
 * to a hardware implementation of the functionality of the software
 * licensed hereunder.  You may use the software subject to the license
 * terms below provided that you ensure that this notice is replicated
 * unmodified and in its entirety in all distributions of the software,
 * modified or unmodified, in source code or in binary form.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met: 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 holders nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * 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: Andreas Sandberg
 */

#ifndef __CPU_KVM_ARM_CPU_HH__
#define __CPU_KVM_ARM_CPU_HH__

#include <set>
#include <vector>

#include "cpu/kvm/base.hh"
#include "params/ArmKvmCPU.hh"

/**
 * ARM implementation of a KVM-based hardware virtualized CPU.
 * Architecture specific limitations:
 *  * LPAE is currently not supported by gem5. We therefore panic if LPAE
 *    is enabled when returning to gem5.
 *  * The co-processor based interface to the architected timer is
 *    unsupported. We can't support this due to limitations in the KVM
 *    API on ARM.
 *  * M5 ops are currently not supported. This requires either a kernel
 *  hack or a memory mapped device that handles the guest<->m5
 *  interface.
 */
class ArmKvmCPU : public BaseKvmCPU
{
  public:
    ArmKvmCPU(ArmKvmCPUParams *params);
    virtual ~ArmKvmCPU();

    void startup();

    void dump();

  protected:
    struct KvmIntRegInfo {
        /** KVM ID */
        const uint64_t id;
        /** gem5 index */
        const IntRegIndex idx;
        /** Name in debug output */
        const char *name;
    };

    struct KvmCoreMiscRegInfo {
        /** KVM ID */
        const uint64_t id;
        /** gem5 index */
        const MiscRegIndex idx;
        /** Name in debug output */
        const char *name;
    };

    typedef std::vector<uint64_t> RegIndexVector;

    void tick();

    void updateKvmState();
    void updateThreadContext();

    /**
     * Get a list of registers supported by getOneReg() and setOneReg().
     */
    const RegIndexVector &getRegList() const;

    void kvmArmVCpuInit(uint32_t target);
    void kvmArmVCpuInit(const struct kvm_vcpu_init &init);

    ArmISA::MiscRegIndex decodeCoProcReg(uint64_t id) const;

    ArmISA::MiscRegIndex decodeVFPCtrlReg(uint64_t id) const;

    /**
     * Determine if a register is invariant.
     *
     * Some registers must have the same value in both the host and
     * the guest. Such registers are referred to as "invariant"
     * registers in KVM. This is a restriction imposed by KVM as
     * having different values in ID registers (e.g., the cache
     * identification registers) would confuse the guest kernel.
     */
    bool isInvariantReg(uint64_t id);

    static KvmIntRegInfo kvmIntRegs[];
    static KvmCoreMiscRegInfo kvmCoreMiscRegs[];

  private:
    /**
     * Get a list of registers supported by getOneReg() and setOneReg().
     *
     * @return False if the number of elements allocated in the list
     * is too small to hold the complete register list (the required
     * value is written into n in this case). True on success.
     */
    bool getRegList(struct kvm_reg_list &regs) const;

    void dumpKvmStateCore();
    void dumpKvmStateMisc();
    void dumpKvmStateCoProc(uint64_t id);
    void dumpKvmStateVFP(uint64_t id);

    void updateKvmStateCore();
    void updateKvmStateMisc();
    void updateKvmStateCoProc(uint64_t id, bool show_warnings);
    void updateKvmStateVFP(uint64_t id, bool show_warnings);

    void updateTCStateCore();
    void updateTCStateMisc();
    void updateTCStateCoProc(uint64_t id, bool show_warnings);
    void updateTCStateVFP(uint64_t id, bool show_warnings);


    /** Cached state of the IRQ line */
    bool irqAsserted;
    /** Cached state of the FIQ line */
    bool fiqAsserted;

    /**
     * Cached copy of the list of co-processor registers supported by
     * KVM
     */
    mutable RegIndexVector _regIndexList;

    /**
     * List of co-processor registers that KVM requires to be
     * identical on both the host and the guest. KVM does not allow
     * writes to these registers.
     */
    static const std::set<uint64_t> invariant_regs;
};

#endif