MdePkg/Library/BaseLib/Ia32/EnableCache.c

/** @file
  AsmEnableCache function

  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.

**/

/**
  Perform a WBINVD and clear both the CD and NW bits of CR0.

  Enables the caches by executing a WBINVD instruction and then clear both the CD and NW
  bits of CR0 to 0.  This function is only available on IA-32 and x64.

**/
VOID
EFIAPI
AsmEnableCache (
  VOID
  )
{
  _asm {
    wbinvd
    mov     eax, cr0
    btr     eax, 30
    btr     eax, 29
    mov     cr0, eax
  }
}