audk/MdePkg/Library/BaseLib/Ia32/DisableCache.asm

46 lines
1.3 KiB
NASM

;------------------------------------------------------------------------------
;
; Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>
; This program and the accompanying materials
; are licensed and made available under the terms and conditions of the BSD License
; which accompanies this distribution. The full text of the license may be found at
; http://opensource.org/licenses/bsd-license.php
;
; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
;
; Module Name:
;
; DisableCache.Asm
;
; Abstract:
;
; Set the CD bit of CR0 to 1, clear the NW bit of CR0 to 0, and flush all caches with a
; WBINVD instruction.
;
; Notes:
;
;------------------------------------------------------------------------------
.486p
.model flat,C
.code
;------------------------------------------------------------------------------
; VOID
; EFIAPI
; AsmDisableCache (
; VOID
; );
;------------------------------------------------------------------------------
AsmDisableCache PROC
mov eax, cr0
bts eax, 30
btr eax, 29
mov cr0, eax
wbinvd
ret
AsmDisableCache ENDP
END