cpuid.cc revision 11793:ef606668d247 
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
33#include "base/bitfield.hh"
34#include "cpu/thread_context.hh"
35
36namespace X86ISA {
37    enum StandardCpuidFunction {
38        VendorAndLargestStdFunc,
39        FamilyModelStepping,
40        NumStandardCpuidFuncs
41    };
42
43    enum ExtendedCpuidFunctions {
44        VendorAndLargestExtFunc,
45        FamilyModelSteppingBrandFeatures,
46        NameString1,
47        NameString2,
48        NameString3,
49        L1CacheAndTLB,
50        L2L3CacheAndL2TLB,
51        APMInfo,
52        LongModeAddressSize,
53
54        /*
55         * The following are defined by the spec but not yet implemented
56         */
57/*      // Function 9 is reserved
58        SVMInfo = 10,
59        // Functions 11-24 are reserved
60        TLB1GBPageInfo = 25,
61        PerformanceInfo,*/
62
63        NumExtendedCpuidFuncs
64    };
65
66    static const int vendorStringSize = 13;
67    static const char vendorString[vendorStringSize] = "M5 Simulator";
68    static const int nameStringSize = 48;
69    static const char nameString[nameStringSize] = "Fake M5 x86_64 CPU";
70
71    uint64_t
72    stringToRegister(const char *str)
73    {
74        uint64_t reg = 0;
75        for (int pos = 3; pos >=0; pos--) {
76            reg <<= 8;
77            reg |= str[pos];
78        }
79        return reg;
80    }
81
82    bool
83    doCpuid(ThreadContext * tc, uint32_t function,
84            uint32_t index, CpuidResult &result)
85    {
86        uint16_t family = bits(function, 31, 16);
87        uint16_t funcNum = bits(function, 15, 0);
88        if (family == 0x8000) {
89            // The extended functions
90            switch (funcNum) {
91              case VendorAndLargestExtFunc:
92                assert(vendorStringSize >= 12);
93                result = CpuidResult(
94                        0x80000000 + NumExtendedCpuidFuncs - 1,
95                        stringToRegister(vendorString),
96                        stringToRegister(vendorString + 4),
97                        stringToRegister(vendorString + 8));
98                break;
99              case FamilyModelSteppingBrandFeatures:
100                result = CpuidResult(0x00020f51, 0x00000405,
101                                     0xe3d3fbff, 0x00000001);
102                break;
103              case NameString1:
104              case NameString2:
105              case NameString3:
106                {
107                    // Zero fill anything beyond the end of the string. This
108                    // should go away once the string is a vetted parameter.
109                    char cleanName[nameStringSize];
110                    memset(cleanName, '\0', nameStringSize);
111                    strncpy(cleanName, nameString, nameStringSize);
112
113                    int offset = (funcNum - NameString1) * 16;
114                    assert(nameStringSize >= offset + 16);
115                    result = CpuidResult(
116                            stringToRegister(cleanName + offset + 0),
117                            stringToRegister(cleanName + offset + 4),
118                            stringToRegister(cleanName + offset + 12),
119                            stringToRegister(cleanName + offset + 8));
120                }
121                break;
122              case L1CacheAndTLB:
123                result = CpuidResult(0xff08ff08, 0xff20ff20,
124                                     0x40020140, 0x40020140);
125                break;
126              case L2L3CacheAndL2TLB:
127                result = CpuidResult(0x00000000, 0x42004200,
128                                     0x00000000, 0x04008140);
129                break;
130              case APMInfo:
131                result = CpuidResult(0x80000018, 0x68747541,
132                                     0x69746e65, 0x444d4163);
133                break;
134              case LongModeAddressSize:
135                result = CpuidResult(0x00003030, 0x00000000,
136                                     0x00000000, 0x00000000);
137                break;
138/*            case SVMInfo:
139              case TLB1GBPageInfo:
140              case PerformanceInfo:*/
141              default:
142                warn("x86 cpuid family 0x8000: unimplemented function %u",
143                    funcNum);
144                return false;
145            }
146        } else if (family == 0x0000) {
147            // The standard functions
148            switch (funcNum) {
149              case VendorAndLargestStdFunc:
150                assert(vendorStringSize >= 12);
151                result = CpuidResult(
152                        NumStandardCpuidFuncs - 1,
153                        stringToRegister(vendorString),
154                        stringToRegister(vendorString + 4),
155                        stringToRegister(vendorString + 8));
156                break;
157              case FamilyModelStepping:
158                result = CpuidResult(0x00020f51, 0x00000805,
159                                     0xe7dbfbff, 0x04000209);
160                break;
161              default:
162                warn("x86 cpuid family 0x0000: unimplemented function %u",
163                    funcNum);
164                return false;
165            }
166        } else {
167            warn("x86 cpuid: unknown family %#x", family);
168            return false;
169        }
170
171        return true;
172    }
173} // namespace X86ISA
174