audk/IntelFspPkg/FspSecCore/Ia32/FspHelper.asm

73 lines
2.2 KiB
NASM

;; @file
; Provide FSP helper function.
;
; Copyright (c) 2015, Intel Corporation. All rights reserved.<BR>
; This program and the accompanying materials
; are licensed and made available under the terms and conditions of the BSD License
; which accompanies this distribution. The full text of the license may be found at
; http://opensource.org/licenses/bsd-license.php.
;
; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
;;
.586p
.model flat,C
.code
;
; FspInfoHeaderRelativeOff is patched during build process and initialized to offset of the AsmGetFspBaseAddress
; from the FSP Info header.
;
FspInfoHeaderRelativeOff PROC NEAR PUBLIC
;
; This value will be pached by the build script
;
DD 012345678h
FspInfoHeaderRelativeOff ENDP
;
; Returns FSP Base Address.
;
; This function gets the FSP Info Header using relative addressing and returns the FSP Base from the header structure
;
AsmGetFspBaseAddress PROC NEAR PUBLIC
mov eax, AsmGetFspBaseAddress
sub eax, dword ptr [FspInfoHeaderRelativeOff]
add eax, 01Ch
mov eax, dword ptr [eax]
ret
AsmGetFspBaseAddress ENDP
;
; No stack counter part of AsmGetFspBaseAddress. Return address is in edi.
;
AsmGetFspBaseAddressNoStack PROC NEAR PUBLIC
mov eax, AsmGetFspBaseAddress
sub eax, dword ptr [FspInfoHeaderRelativeOff]
add eax, 01Ch
mov eax, dword ptr [eax]
jmp edi
AsmGetFspBaseAddressNoStack ENDP
;
; Returns FSP Info Header.
;
; This function gets the FSP Info Header using relative addressing and returns it
;
AsmGetFspInfoHeader PROC NEAR PUBLIC
mov eax, AsmGetFspBaseAddress
sub eax, dword ptr [FspInfoHeaderRelativeOff]
ret
AsmGetFspInfoHeader ENDP
;
; No stack counter part of AsmGetFspInfoHeader. Return address is in edi.
;
AsmGetFspInfoHeaderNoStack PROC NEAR PUBLIC
mov eax, AsmGetFspBaseAddress
sub eax, dword ptr [FspInfoHeaderRelativeOff]
jmp edi
AsmGetFspInfoHeaderNoStack ENDP
END