mirror of
https://github.com/CloverHackyColor/CloverBootloader.git
synced 2024-11-27 12:15:19 +01:00
69 lines
2.2 KiB
C
69 lines
2.2 KiB
C
/** @file
|
|
AsmCpuid function.
|
|
|
|
Copyright (c) 2006 - 2010, Intel Corporation. All rights reserved.<BR>
|
|
SPDX-License-Identifier: BSD-2-Clause-Patent
|
|
|
|
**/
|
|
|
|
/**
|
|
Retrieves CPUID information.
|
|
|
|
Executes the CPUID instruction with EAX set to the value specified by Index.
|
|
This function always returns Index.
|
|
If Eax is not NULL, then the value of EAX after CPUID is returned in Eax.
|
|
If Ebx is not NULL, then the value of EBX after CPUID is returned in Ebx.
|
|
If Ecx is not NULL, then the value of ECX after CPUID is returned in Ecx.
|
|
If Edx is not NULL, then the value of EDX after CPUID is returned in Edx.
|
|
This function is only available on IA-32 and x64.
|
|
|
|
@param Index The 32-bit value to load into EAX prior to invoking the CPUID
|
|
instruction.
|
|
@param RegisterEax A pointer to the 32-bit EAX value returned by the CPUID
|
|
instruction. This is an optional parameter that may be NULL.
|
|
@param RegisterEbx A pointer to the 32-bit EBX value returned by the CPUID
|
|
instruction. This is an optional parameter that may be NULL.
|
|
@param RegisterEcx A pointer to the 32-bit ECX value returned by the CPUID
|
|
instruction. This is an optional parameter that may be NULL.
|
|
@param RegisterEdx A pointer to the 32-bit EDX value returned by the CPUID
|
|
instruction. This is an optional parameter that may be NULL.
|
|
|
|
@return Index.
|
|
|
|
**/
|
|
UINT32
|
|
EFIAPI
|
|
AsmCpuid (
|
|
IN UINT32 Index,
|
|
OUT UINT32 *RegisterEax, OPTIONAL
|
|
OUT UINT32 *RegisterEbx, OPTIONAL
|
|
OUT UINT32 *RegisterEcx, OPTIONAL
|
|
OUT UINT32 *RegisterEdx OPTIONAL
|
|
)
|
|
{
|
|
_asm {
|
|
mov eax, Index
|
|
cpuid
|
|
push ecx
|
|
mov ecx, RegisterEax
|
|
jecxz SkipEax
|
|
mov [ecx], eax
|
|
SkipEax:
|
|
mov ecx, RegisterEbx
|
|
jecxz SkipEbx
|
|
mov [ecx], ebx
|
|
SkipEbx:
|
|
pop eax
|
|
mov ecx, RegisterEcx
|
|
jecxz SkipEcx
|
|
mov [ecx], eax
|
|
SkipEcx:
|
|
mov ecx, RegisterEdx
|
|
jecxz SkipEdx
|
|
mov [ecx], edx
|
|
SkipEdx:
|
|
mov eax, Index
|
|
}
|
|
}
|
|
|