MdePkg/Library/BaseLib/X64/WriteMsr64.S

   1 #------------------------------------------------------------------------------
   2 #
   3 # Copyright (c) 2006, Intel Corporation
   4 # All rights reserved. This program and the accompanying materials
   5 # are licensed and made available under the terms and conditions of the BSD License
   6 # which accompanies this distribution.  The full text of the license may be found at
   7 # http://opensource.org/licenses/bsd-license.php
   8 #
   9 # THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  10 # WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  11 #
  12 # Module Name:
  13 #
  14 #   WriteMsr64.S
  15 #
  16 # Abstract:
  17 #
  18 #   AsmWriteMsr64 function
  19 #
  20 # Notes:
  21 #
  22 #------------------------------------------------------------------------------
  23
  24
  25 #------------------------------------------------------------------------------
  26 # UINT64
  27 # EFIAPI
  28 # AsmWriteMsr64 (
  29 #   IN UINT32  Index,
  30 #   IN UINT64  Value
  31 #   );
  32 # TODO:
  33 #------------------------------------------------------------------------------
  34 .global ASM_PFX(AsmWriteMsr64)
  35 .align 16
  36 ASM_PFX(AsmWriteMsr64):
  37     mov %rdx, %rax
  38     shr $0x20, %rdx
  39     wrmsr
  40     ret