MdePkg/Library/BaseLib/Ia32/CpuIdEx.c

   1 /** @file
   2   AsmCpuidEx function.
   3
   4   Copyright (c) 2006, 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 #if _MSC_EXTENSIONS
  16
  17 UINT32
  18 EFIAPI
  19 AsmCpuidEx (
  20   IN      UINT32                    Index,
  21   IN      UINT32                    SubIndex,
  22   OUT     UINT32                    *RegisterEax,  OPTIONAL
  23   OUT     UINT32                    *RegisterEbx,  OPTIONAL
  24   OUT     UINT32                    *RegisterEcx,  OPTIONAL
  25   OUT     UINT32                    *RegisterEdx   OPTIONAL
  26   )
  27 {
  28   _asm {
  29     mov     eax, Index
  30     mov     ecx, SubIndex
  31     cpuid
  32     push    ecx
  33     mov     ecx, RegisterEax
  34     jecxz   SkipEax
  35     mov     [ecx], eax
  36 SkipEax:
  37     mov     ecx, RegisterEbx
  38     jecxz   SkipEbx
  39     mov     [ecx], ebx
  40 SkipEbx:
  41     pop     eax
  42     mov     ecx, RegisterEcx
  43     jecxz   SkipEcx
  44     mov     [ecx], eax
  45 SkipEcx:
  46     mov     ecx, RegisterEdx
  47     jecxz   SkipEdx
  48     mov     [ecx], edx
  49 SkipEdx:
  50     mov     eax, Index
  51   }
  52 }
  53
  54 #endif