CloverBootloader/MdePkg/Library/BaseLib/X64/CpuId.nasm

59 lines
1.4 KiB
NASM
Raw Normal View History

;------------------------------------------------------------------------------
;
; Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>
; SPDX-License-Identifier: BSD-2-Clause-Patent
;
; Module Name:
;
; CpuId.Asm
;
; Abstract:
;
; AsmCpuid function
;
; Notes:
;
;------------------------------------------------------------------------------
DEFAULT REL
SECTION .text
;------------------------------------------------------------------------------
; VOID
; EFIAPI
; AsmCpuid (
; IN UINT32 RegisterInEax,
; OUT UINT32 *RegisterOutEax OPTIONAL,
; OUT UINT32 *RegisterOutEbx OPTIONAL,
; OUT UINT32 *RegisterOutEcx OPTIONAL,
; OUT UINT32 *RegisterOutEdx OPTIONAL
; )
;------------------------------------------------------------------------------
global ASM_PFX(AsmCpuid)
ASM_PFX(AsmCpuid):
push rbx
mov eax, ecx
push rax ; save Index on stack
push rdx
cpuid
test r9, r9
jz .0
mov [r9], ecx
.0:
pop rcx
jrcxz .1
mov [rcx], eax
.1:
mov rcx, r8
jrcxz .2
mov [rcx], ebx
.2:
mov rcx, [rsp + 0x38]
jrcxz .3
mov [rcx], edx
.3:
pop rax ; restore Index to rax as return value
pop rbx
ret