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;------------------------------------------------------------------------------
;
; Copyright (c) 2006, Intel Corporation. All rights reserved.<BR>
; SPDX-License-Identifier: BSD-2-Clause-Patent
;
; Module Name:
;
;   WriteMsr64.Asm
;
; Abstract:
;
;   AsmWriteMsr64 function
;
; Notes:
;
;------------------------------------------------------------------------------

    DEFAULT REL
    SECTION .text

;------------------------------------------------------------------------------
; UINT64
; EFIAPI
; AsmWriteMsr64 (
;   IN UINT32  Index,
;   IN UINT64  Value
;   );
;------------------------------------------------------------------------------
global ASM_PFX(AsmWriteMsr64)
ASM_PFX(AsmWriteMsr64):
    mov     rax, rdx                    ; meanwhile, rax <- return value
    shr     rdx, 0x20                    ; edx:eax contains the value to write
    wrmsr
    ret