cpuid.cc revision 6068:f70c90e29577 
1/*
2 * Copyright (c) 2008 The Regents of The University of Michigan
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met: redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer;
9 * redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution;
12 * neither the name of the copyright holders nor the names of its
13 * contributors may be used to endorse or promote products derived from
14 * this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * Authors: Gabe Black
29 */
30
31#include "arch/x86/cpuid.hh"
32#include "base/bitfield.hh"
33#include "cpu/thread_context.hh"
34
35namespace X86ISA {
36    enum StandardCpuidFunction {
37        VendorAndLargestStdFunc,
38        FamilyModelStepping,
39        NumStandardCpuidFuncs
40    };
41
42    enum ExtendedCpuidFunctions {
43        VendorAndLargestExtFunc,
44        FamilyModelSteppingBrandFeatures,
45        NameString1,
46        NameString2,
47        NameString3,
48        L1CacheAndTLB,
49        L2L3CacheAndL2TLB,
50        APMInfo,
51
52        /*
53         * The following are defined by the spec but not yet implemented
54         */
55/*      LongModeAddressSize,
56        // Function 9 is reserved
57        SVMInfo = 10,
58        // Functions 11-24 are reserved
59        TLB1GBPageInfo = 25,
60        PerformanceInfo,*/
61
62        NumExtendedCpuidFuncs
63    };
64
65    static const int vendorStringSize = 13;
66    static const char vendorString[vendorStringSize] = "M5 Simulator";
67    static const int nameStringSize = 48;
68    static const char nameString[nameStringSize] = "Fake M5 x86_64 CPU";
69
70    uint64_t
71    stringToRegister(const char *str)
72    {
73        uint64_t reg = 0;
74        for (int pos = 3; pos >=0; pos--) {
75            reg <<= 8;
76            reg |= str[pos];
77        }
78        return reg;
79    }
80
81    bool
82    doCpuid(ThreadContext * tc, uint32_t function, CpuidResult &result)
83    {
84        uint16_t family = bits(function, 31, 16);
85        uint16_t funcNum = bits(function, 15, 0);
86        if (family == 0x8000) {
87            // The extended functions
88            switch (funcNum) {
89              case VendorAndLargestExtFunc:
90                assert(vendorStringSize >= 12);
91                result = CpuidResult(
92                        0x80000000 + NumExtendedCpuidFuncs - 1,
93                        stringToRegister(vendorString),
94                        stringToRegister(vendorString + 4),
95                        stringToRegister(vendorString + 8));
96                break;
97              case FamilyModelSteppingBrandFeatures:
98                result = CpuidResult(0x00020f51, 0x00000405,
99                                     0xe3d3fbff, 0x00000001);
100                break;
101              case NameString1:
102              case NameString2:
103              case NameString3:
104                {
105                    // Zero fill anything beyond the end of the string. This
106                    // should go away once the string is a vetted parameter.
107                    char cleanName[nameStringSize];
108                    memset(cleanName, '\0', nameStringSize);
109                    strncpy(cleanName, nameString, nameStringSize);
110
111                    int offset = (funcNum - NameString1) * 16;
112                    assert(nameStringSize >= offset + 16);
113                    result = CpuidResult(
114                            stringToRegister(cleanName + offset + 0),
115                            stringToRegister(cleanName + offset + 4),
116                            stringToRegister(cleanName + offset + 12),
117                            stringToRegister(cleanName + offset + 8));
118                }
119                break;
120              case L1CacheAndTLB:
121                result = CpuidResult(0xff08ff08, 0xff20ff20,
122                                     0x40020140, 0x40020140);
123                break;
124              case L2L3CacheAndL2TLB:
125                result = CpuidResult(0x00000000, 0x42004200,
126                                     0x00000000, 0x04008140);
127                break;
128              case APMInfo:
129                result = CpuidResult(0x80000018, 0x68747541,
130                                     0x69746e65, 0x444d4163);
131                break;
132/*            case LongModeAddressSize:
133              case SVMInfo:
134              case TLB1GBPageInfo:
135              case PerformanceInfo:*/
136              default:
137                return false;
138            }
139        } else if(family == 0x0000) {
140            // The standard functions
141            switch (funcNum) {
142              case VendorAndLargestStdFunc:
143                assert(vendorStringSize >= 12);
144                result = CpuidResult(
145                        NumStandardCpuidFuncs - 1,
146                        stringToRegister(vendorString),
147                        stringToRegister(vendorString + 4),
148                        stringToRegister(vendorString + 8));
149                break;
150              case FamilyModelStepping:
151                result = CpuidResult(0x00020f51, 0000000405,
152                                     0xe7d3fbff, 0x00000001);
153                break;
154              default:
155                return false;
156            }
157        }
158        return true;
159    }
160} //namespace X86ISA
161