MdePkg/Library/BaseLib/Ia32/WriteLdtr.c

   1 /** @file
   2   AsmWriteLdtr function
   3
   4   Copyright (c) 2006 - 2007, Intel Corporation<BR>
   5   All rights reserved. This program and the accompanying materials
   6   are licensed and made available under the terms and conditions of the BSD License
   7   which accompanies this distribution.  The full text of the license may be found at
   8   http://opensource.org/licenses/bsd-license.php
   9
  10   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12
  13 **/
  14
  15
  16
  17
  18 /**
  19   Writes the current Local Descriptor Table Register (GDTR) selector.
  20
  21   Writes and the current LDTR descriptor specified by Ldtr. This function is
  22   only available on IA-32 and x64.
  23
  24   @param  Ldtr  16-bit LDTR selector value.
  25
  26 **/
  27 VOID
  28 EFIAPI
  29 AsmWriteLdtr (
  30   IN UINT16 Ldtr
  31   )
  32 {
  33   _asm {
  34     xor     eax, eax
  35     mov     ax, Ldtr
  36     lldt    ax
  37   }
  38 }
  39