projects / mirror_edk2.git / blame
| Commit | Line | Data |
|---|---|---|
| e1f414b6 | 1 | /** @file\r |
| 2 | AsmCpuid function.\r | |
| 3 | \r | |
| 35a17154 | 4 | Copyright (c) 2006 - 2010, Intel Corporation. All rights reserved.<BR>\r |
| 9344f092 | 5 | SPDX-License-Identifier: BSD-2-Clause-Patent\r |
| e1f414b6 | 6 | \r |
| 7 | **/\r | |
| 8 | \r | |
| 42eedea9 | 9 | /**\r |
| 10 | Retrieves CPUID information.\r | |
| 11 | \r | |
| 12 | Executes the CPUID instruction with EAX set to the value specified by Index.\r | |
| 13 | This function always returns Index.\r | |
| 14 | If Eax is not NULL, then the value of EAX after CPUID is returned in Eax.\r | |
| 15 | If Ebx is not NULL, then the value of EBX after CPUID is returned in Ebx.\r | |
| 16 | If Ecx is not NULL, then the value of ECX after CPUID is returned in Ecx.\r | |
| 17 | If Edx is not NULL, then the value of EDX after CPUID is returned in Edx.\r | |
| 030cd1a2 | 18 | This function is only available on IA-32 and x64.\r |
| 42eedea9 | 19 | \r |
| 44b013bd | 20 | @param Index The 32-bit value to load into EAX prior to invoking the CPUID\r |
| 21 | instruction.\r | |
| 35a17154 | 22 | @param RegisterEax A pointer to the 32-bit EAX value returned by the CPUID\r |
| 44b013bd | 23 | instruction. This is an optional parameter that may be NULL.\r |
| 35a17154 | 24 | @param RegisterEbx A pointer to the 32-bit EBX value returned by the CPUID\r |
| 44b013bd | 25 | instruction. This is an optional parameter that may be NULL.\r |
| 35a17154 | 26 | @param RegisterEcx A pointer to the 32-bit ECX value returned by the CPUID\r |
| 44b013bd | 27 | instruction. This is an optional parameter that may be NULL.\r |
| 35a17154 | 28 | @param RegisterEdx A pointer to the 32-bit EDX value returned by the CPUID\r |
| 44b013bd | 29 | instruction. This is an optional parameter that may be NULL.\r |
| 42eedea9 | 30 | \r |
| 2fe241a2 | 31 | @return Index.\r |
| 42eedea9 | 32 | \r |
| 33 | **/\r | |
| e1f414b6 | 34 | UINT32\r |
| 35 | EFIAPI\r | |
| 36 | AsmCpuid (\r | |
| 2f88bd3a MK |
37 | IN UINT32 Index,\r |
| 38 | OUT UINT32 *RegisterEax OPTIONAL,\r | |
| 39 | OUT UINT32 *RegisterEbx OPTIONAL,\r | |
| 40 | OUT UINT32 *RegisterEcx OPTIONAL,\r | |
| 41 | OUT UINT32 *RegisterEdx OPTIONAL\r | |
| e1f414b6 | 42 | )\r |
| 43 | {\r | |
| 44 | _asm {\r | |
| 45 | mov eax, Index\r | |
| 46 | cpuid\r | |
| 47 | push ecx\r | |
| 14f268ba | 48 | mov ecx, RegisterEax\r |
| e1f414b6 | 49 | jecxz SkipEax\r |
| 50 | mov [ecx], eax\r | |
| 51 | SkipEax:\r | |
| 14f268ba | 52 | mov ecx, RegisterEbx\r |
| e1f414b6 | 53 | jecxz SkipEbx\r |
| 54 | mov [ecx], ebx\r | |
| 55 | SkipEbx:\r | |
| 56 | pop eax\r | |
| 14f268ba | 57 | mov ecx, RegisterEcx\r |
| e1f414b6 | 58 | jecxz SkipEcx\r |
| 59 | mov [ecx], eax\r | |
| 60 | SkipEcx:\r | |
| 14f268ba | 61 | mov ecx, RegisterEdx\r |
| e1f414b6 | 62 | jecxz SkipEdx\r |
| 63 | mov [ecx], edx\r | |
| 64 | SkipEdx:\r | |
| 65 | mov eax, Index\r | |
| 66 | }\r | |
| 67 | }\r |