EdkCompatibilityPkg/Foundation/Library/EdkIIGlueLib/Library/BaseLib/X64/CpuId.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 #   CpuId.S
  15 #
  16 # Abstract:
  17 #
  18 #   AsmCpuid function
  19 #
  20 # Notes:
  21 #
  22 #------------------------------------------------------------------------------
  23
  24 #include <EdkIIGlueBase.h>
  25
  26 #------------------------------------------------------------------------------
  27 #  VOID
  28 #  EFIAPI
  29 #  AsmCpuid (
  30 #    IN   UINT32  RegisterInEax,
  31 #    OUT  UINT32  *RegisterOutEax  OPTIONAL,
  32 #    OUT  UINT32  *RegisterOutEbx  OPTIONAL,
  33 #    OUT  UINT32  *RegisterOutEcx  OPTIONAL,
  34 #    OUT  UINT32  *RegisterOutEdx  OPTIONAL
  35 #    )
  36 #------------------------------------------------------------------------------
  37 .globl ASM_PFX(AsmCpuid)
  38 ASM_PFX(AsmCpuid):
  39     push    %rbx
  40     mov     %ecx, %eax
  41     push    %rax                         # save Index on stack
  42     push    %rdx
  43     cpuid
  44     test    %r9, %r9
  45     jz      L1
  46     mov     %ecx, (%r9)
  47 L1:
  48     pop     %rcx
  49     jrcxz   L2
  50     mov     %eax, (%rcx)
  51 L2:
  52     mov     %r8, %rcx
  53     jrcxz   L3
  54     mov     %ebx, (%rcx)
  55 L3:
  56     mov     0x38(%rsp), %rcx
  57     jrcxz   L4
  58     mov     %edx, (%rcx)
  59 L4:
  60     pop     %rax                         # restore Index to rax as return value
  61     pop     %rbx
  62     ret