mirror of
https://github.com/CloverHackyColor/CloverBootloader.git
synced 2024-11-27 12:15:19 +01:00
40 lines
1.0 KiB
NASM
40 lines
1.0 KiB
NASM
;------------------------------------------------------------------------------
|
|
;
|
|
; Copyright (c) 2006, Intel Corporation. All rights reserved.<BR>
|
|
; SPDX-License-Identifier: BSD-2-Clause-Patent
|
|
;
|
|
; Module Name:
|
|
;
|
|
; WriteDr4.Asm
|
|
;
|
|
; Abstract:
|
|
;
|
|
; AsmWriteDr4 function
|
|
;
|
|
; Notes:
|
|
;
|
|
;------------------------------------------------------------------------------
|
|
|
|
SECTION .text
|
|
|
|
;------------------------------------------------------------------------------
|
|
; UINTN
|
|
; EFIAPI
|
|
; AsmWriteDr4 (
|
|
; IN UINTN Value
|
|
; );
|
|
;------------------------------------------------------------------------------
|
|
global ASM_PFX(AsmWriteDr4)
|
|
ASM_PFX(AsmWriteDr4):
|
|
mov eax, [esp + 4]
|
|
;
|
|
; DR4 is alias to DR6 only if DE (in CR4) is cleared. Otherwise, writing to
|
|
; this register will cause a #UD exception.
|
|
;
|
|
; MS assembler doesn't support this instruction since no one would use it
|
|
; under normal circustances. Here opcode is used.
|
|
;
|
|
DB 0xf, 0x23, 0xe0
|
|
ret
|
|
|