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path: root/MdePkg/Library/BaseLib/Ia32/EnableCache.nasm
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;------------------------------------------------------------------------------
;
; Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>
; SPDX-License-Identifier: BSD-2-Clause-Patent
;
; Module Name:
;
;   EnableCache.Asm
;
; Abstract:
;
;  Flush all caches with a WBINVD instruction, clear the CD bit of CR0 to 0, and clear
;  the NW bit of CR0 to 0
;
; Notes:
;
;------------------------------------------------------------------------------

    SECTION .text

;------------------------------------------------------------------------------
; VOID
; EFIAPI
; AsmEnableCache (
;   VOID
;   );
;------------------------------------------------------------------------------
global ASM_PFX(AsmEnableCache)
ASM_PFX(AsmEnableCache):
    wbinvd
    mov     eax, cr0
    btr     eax, 29
    btr     eax, 30
    mov     cr0, eax
    ret