cpuid.cc revision 9124:3476c436d248 
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,
83            uint32_t index, CpuidResult &result)
84    {
85        uint16_t family = bits(function, 31, 16);
86        uint16_t funcNum = bits(function, 15, 0);
87        if (family == 0x8000) {
88            // The extended functions
89            switch (funcNum) {
90              case VendorAndLargestExtFunc:
91                assert(vendorStringSize >= 12);
92                result = CpuidResult(
93                        0x80000000 + NumExtendedCpuidFuncs - 1,
94                        stringToRegister(vendorString),
95                        stringToRegister(vendorString + 4),
96                        stringToRegister(vendorString + 8));
97                break;
98              case FamilyModelSteppingBrandFeatures:
99                result = CpuidResult(0x00020f51, 0x00000405,
100                                     0xe3d3fbff, 0x00000001);
101                break;
102              case NameString1:
103              case NameString2:
104              case NameString3:
105                {
106                    // Zero fill anything beyond the end of the string. This
107                    // should go away once the string is a vetted parameter.
108                    char cleanName[nameStringSize];
109                    memset(cleanName, '\0', nameStringSize);
110                    strncpy(cleanName, nameString, nameStringSize);
111
112                    int offset = (funcNum - NameString1) * 16;
113                    assert(nameStringSize >= offset + 16);
114                    result = CpuidResult(
115                            stringToRegister(cleanName + offset + 0),
116                            stringToRegister(cleanName + offset + 4),
117                            stringToRegister(cleanName + offset + 12),
118                            stringToRegister(cleanName + offset + 8));
119                }
120                break;
121              case L1CacheAndTLB:
122                result = CpuidResult(0xff08ff08, 0xff20ff20,
123                                     0x40020140, 0x40020140);
124                break;
125              case L2L3CacheAndL2TLB:
126                result = CpuidResult(0x00000000, 0x42004200,
127                                     0x00000000, 0x04008140);
128                break;
129              case APMInfo:
130                result = CpuidResult(0x80000018, 0x68747541,
131                                     0x69746e65, 0x444d4163);
132                break;
133/*            case LongModeAddressSize:
134              case SVMInfo:
135              case TLB1GBPageInfo:
136              case PerformanceInfo:*/
137              default:
138                warn("x86 cpuid: unimplemented function %u", funcNum);
139                return false;
140            }
141        } else if(family == 0x0000) {
142            // The standard functions
143            switch (funcNum) {
144              case VendorAndLargestStdFunc:
145                assert(vendorStringSize >= 12);
146                result = CpuidResult(
147                        NumStandardCpuidFuncs - 1,
148                        stringToRegister(vendorString),
149                        stringToRegister(vendorString + 4),
150                        stringToRegister(vendorString + 8));
151                break;
152              case FamilyModelStepping:
153                result = CpuidResult(0x00020f51, 0000000405,
154                                     0xe7d3fbff, 0x00000001);
155                break;
156              default:
157                warn("x86 cpuid: unimplemented function %u", funcNum);
158                return false;
159            }
160        } else {
161            warn("x86 cpuid: unknown family %#x", family);
162            return false;
163        }
164
165        return true;
166    }
167} // namespace X86ISA
168