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Diffstat (limited to 'MdePkg/Library/BaseLib/Ia32/DisableCache.c')
-rw-r--r--MdePkg/Library/BaseLib/Ia32/DisableCache.c36
1 files changed, 36 insertions, 0 deletions
diff --git a/MdePkg/Library/BaseLib/Ia32/DisableCache.c b/MdePkg/Library/BaseLib/Ia32/DisableCache.c
new file mode 100644
index 0000000000..d2d028a93d
--- /dev/null
+++ b/MdePkg/Library/BaseLib/Ia32/DisableCache.c
@@ -0,0 +1,36 @@
+/** @file
+ AsmDisableCache function
+
+ Copyright (c) 2006 - 2008, Intel Corporation<BR>
+ All rights reserved. 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.
+
+**/
+
+/**
+ Disables caches.
+
+ Set the CD bit of CR0 to 1, clear the NW bit of CR0 to 0, and flush all caches with a
+ WBINVD instruction.
+
+**/
+VOID
+EFIAPI
+AsmDisableCache (
+ VOID
+ )
+{
+ _asm {
+ mov eax, cr0
+ bts eax, 30
+ btr eax, 29
+ mov cr0, eax
+ wbinvd
+ }
+}
+