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/** @file
AsmWriteCr4 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.
**/
/**
Writes a value to Control Register 4 (CR4).
Writes and returns a new value to CR4. This function is only available on
IA-32 and x64. This writes a 32-bit value on IA-32 and a 64-bit value on x64.
@param Value The value to write to CR4.
@return The value written to CR4.
**/
UINTN
EFIAPI
AsmWriteCr4 (
UINTN Value
)
{
_asm {
mov eax, Value
_emit 0x0f // mov cr4, eax
_emit 0x22
_emit 0xE0
}
}
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