IntelFspPkg/FspSecCore/Ia32/FspHelper.asm

   1 ;; @file
   2 ;  Provide FSP helper function.
   3 ;
   4 ; Copyright (c) 2015, Intel Corporation. All rights reserved.<BR>
   5 ; 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     .586p
  15     .model  flat,C
  16     .code
  17
  18 ;
  19 ; FspInfoHeaderRelativeOff is patched during build process and initialized to offset of the  AsmGetFspBaseAddress
  20 ; from the FSP Info header.
  21 ;
  22 FspInfoHeaderRelativeOff    PROC      NEAR    PUBLIC
  23    ;
  24    ; This value will be pached by the build script
  25    ;
  26    DD    012345678h
  27 FspInfoHeaderRelativeOff    ENDP
  28
  29 ;
  30 ; Returns FSP Base Address.
  31 ;
  32 ; This function gets the FSP Info Header using relative addressing and returns the FSP Base from the header structure
  33 ;
  34 AsmGetFspBaseAddress        PROC      NEAR    PUBLIC
  35    mov   eax, AsmGetFspBaseAddress
  36    sub   eax, dword ptr [FspInfoHeaderRelativeOff]
  37    add   eax, 01Ch
  38    mov   eax, dword ptr [eax]
  39    ret
  40 AsmGetFspBaseAddress        ENDP
  41
  42 ;
  43 ; No stack counter part of AsmGetFspBaseAddress. Return address is in edi.
  44 ;
  45 AsmGetFspBaseAddressNoStack    PROC      NEAR    PUBLIC
  46    mov   eax, AsmGetFspBaseAddress
  47    sub   eax, dword ptr [FspInfoHeaderRelativeOff]
  48    add   eax, 01Ch
  49    mov   eax, dword ptr [eax]
  50    jmp   edi
  51 AsmGetFspBaseAddressNoStack    ENDP
  52
  53 ;
  54 ; Returns FSP Info Header.
  55 ;
  56 ; This function gets the FSP Info Header using relative addressing and returns it
  57 ;
  58 AsmGetFspInfoHeader         PROC      NEAR    PUBLIC
  59    mov   eax, AsmGetFspBaseAddress
  60    sub   eax, dword ptr [FspInfoHeaderRelativeOff]
  61    ret
  62 AsmGetFspInfoHeader         ENDP
  63
  64 ;
  65 ; No stack counter part of AsmGetFspInfoHeader. Return address is in edi.
  66 ;
  67 AsmGetFspInfoHeaderNoStack         PROC      NEAR    PUBLIC
  68    mov   eax, AsmGetFspBaseAddress
  69    sub   eax, dword ptr [FspInfoHeaderRelativeOff]
  70    jmp   edi
  71 AsmGetFspInfoHeaderNoStack         ENDP
  72
  73      END