IntelFspPkg/FspSecCore/Ia32/FspHelper.s

   1 #------------------------------------------------------------------------------
   2 #
   3 # Copyright (c) 2015, Intel Corporation. All rights reserved.<BR>
   4 # SPDX-License-Identifier: BSD-2-Clause-Patent
   5 #
   6 # Abstract:
   7 #
   8 #   Provide FSP helper function.
   9 #
  10 #------------------------------------------------------------------------------
  11
  12 #
  13 # FspInfoHeaderRelativeOff is patched during build process and initialized to offset of the  AsmGetFspBaseAddress
  14 # from the FSP Info header.
  15 #
  16 ASM_GLOBAL ASM_PFX(FspInfoHeaderRelativeOff)
  17 ASM_PFX(FspInfoHeaderRelativeOff):
  18    #
  19    # This value will be pached by the build script
  20    #
  21    .long    0x012345678
  22
  23 #
  24 # Returns FSP Base Address.
  25 #
  26 # This function gets the FSP Info Header using relative addressing and returns the FSP Base from the header structure
  27 #
  28 ASM_GLOBAL ASM_PFX(AsmGetFspBaseAddress)
  29 ASM_PFX(AsmGetFspBaseAddress):
  30    mov    $AsmGetFspBaseAddress, %eax
  31    sub    FspInfoHeaderRelativeOff, %eax
  32    add    $0x01C, %eax
  33    mov    (%eax), %eax
  34    ret
  35
  36 #
  37 # No stack counter part of AsmGetFspBaseAddress. Return address is in edi.
  38 #
  39 ASM_GLOBAL ASM_PFX(AsmGetFspBaseAddressNoStack)
  40 ASM_PFX(AsmGetFspBaseAddressNoStack):
  41    mov    $AsmGetFspBaseAddress, %eax
  42    sub    FspInfoHeaderRelativeOff, %eax
  43    add    $0x01C, %eax
  44    mov    (%eax), %eax
  45    jmp    *%edi
  46
  47 #
  48 # Returns FSP Info Header.
  49 #
  50 # This function gets the FSP Info Header using relative addressing and returns it
  51 #
  52 ASM_GLOBAL ASM_PFX(AsmGetFspInfoHeader)
  53 ASM_PFX(AsmGetFspInfoHeader):
  54    mov    $AsmGetFspBaseAddress, %eax
  55    sub    FspInfoHeaderRelativeOff, %eax
  56    ret
  57
  58 #
  59 # No stack counter part of AsmGetFspInfoHeader. Return address is in edi.
  60 #
  61 ASM_GLOBAL ASM_PFX(AsmGetFspInfoHeaderNoStack)
  62 ASM_PFX(AsmGetFspInfoHeaderNoStack):
  63    mov    $AsmGetFspBaseAddress, %eax
  64    sub    FspInfoHeaderRelativeOff, %eax
  65    jmp    *%edi