audk/MdePkg/Library/BaseLib/Ia32/EnableCache.c
Michael D Kinney 9344f09215 MdePkg: Replace BSD License with BSD+Patent License
https://bugzilla.tianocore.org/show_bug.cgi?id=1373

Replace BSD 2-Clause License with BSD+Patent License.  This change is
based on the following emails:

  https://lists.01.org/pipermail/edk2-devel/2019-February/036260.html
  https://lists.01.org/pipermail/edk2-devel/2018-October/030385.html

RFCs with detailed process for the license change:

  V3: https://lists.01.org/pipermail/edk2-devel/2019-March/038116.html
  V2: https://lists.01.org/pipermail/edk2-devel/2019-March/037669.html
  V1: https://lists.01.org/pipermail/edk2-devel/2019-March/037500.html

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Michael D Kinney <michael.d.kinney@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
2019-04-09 10:58:13 -07:00

31 lines
575 B
C

/** @file
AsmEnableCache function
Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
/**
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
}
}