Re: [PATCH] IntelFsp2Pkg: Add function to get FspInfoHeader before stack is ready

["Yao, Jiewen" <jiewen.yao@intel.com>]

Reviewed-by: Jiewen.yao@intel.com

> -----Original Message-----
> From: Yarlagadda, Satya P
> Sent: Thursday, August 18, 2016 1:21 PM
> To: edk2-devel@lists.01.org
> Cc: Ma, Maurice <maurice.ma@intel.com>; Yao, Jiewen
> <jiewen.yao@intel.com>; Mudusuru, Giri P <giri.p.mudusuru@intel.com>
> Subject: [PATCH] IntelFsp2Pkg: Add function to get FspInfoHeader before
> stack is ready
> 
> we need to locate the FSP Info Header before the stack is initialized to
> access the cfg region for any UPD. Hence adding the
> AsmGetFspInfoHeaderNoStack function to support it.
> 
> Note: This function is there in IntelFspPkg but got removed in IntelFsp2Pkg
> 
> Cc: Maurice Ma <maurice.ma@intel.com>
> Cc: Jiewen Yao <jiewen.yao@intel.com>
> Cc: Giri P Mudusuru <giri.p.mudusuru@intel.com>
> Contributed-under: TianoCore Contribution Agreement 1.0
> Signed-off-by: Satya Yarlagadda <satya.p.yarlagadda@intel.com>
> ---
>  IntelFsp2Pkg/FspSecCore/Ia32/FspHelper.nasm | 11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/IntelFsp2Pkg/FspSecCore/Ia32/FspHelper.nasm
> b/IntelFsp2Pkg/FspSecCore/Ia32/FspHelper.nasm
> index 43eac97..a848dcb 100644
> --- a/IntelFsp2Pkg/FspSecCore/Ia32/FspHelper.nasm
> +++ b/IntelFsp2Pkg/FspSecCore/Ia32/FspHelper.nasm
> @@ -14,6 +14,8 @@
>      SECTION .text
> 
>  global ASM_PFX(FspInfoHeaderRelativeOff)
> +ASM_PFX(FspInfoHeaderRelativeOff):
> +   DD    0x12345678               ; This value must be patched by
> the build script
> 
>  global ASM_PFX(AsmGetFspBaseAddress)
>  ASM_PFX(AsmGetFspBaseAddress):
> @@ -29,6 +31,11 @@ ASM_PFX(NextInstruction):
>     pop   eax
>     sub   eax, ASM_PFX(NextInstruction)
>     add   eax, ASM_PFX(AsmGetFspInfoHeader)
> -   DB    02Dh                                               ;
> opcode of sub eax, imm32
> -ASM_PFX(FspInfoHeaderRelativeOff):    DD    0x12345678      ; sub
> eax, FspInfoHeaderRelativeOff
> +   sub   eax, dword [ASM_PFX(FspInfoHeaderRelativeOff)]
>     ret
> +
> +global ASM_PFX(AsmGetFspInfoHeaderNoStack)
> +ASM_PFX(AsmGetFspInfoHeaderNoStack):
> +   mov   eax, ASM_PFX(AsmGetFspInfoHeader)
> +   sub   eax, dword [ASM_PFX(FspInfoHeaderRelativeOff)]
> +   jmp   edi
> --
> 2.9.2.windows.1