IntelFsp2Pkg: Locate FSP Info Header dynamically

we need to locate the FSP Info Header by calculating offset dynamically to
handle the scenario of FSP component is being rebased to different location.

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>
Reviewed-by: Maurice Ma <maurice.ma@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Reviewed-by: Giri P Mudusuru <giri.p.mudusuru@intel.com>

diff --git a/IntelFsp2Pkg/FspSecCore/Ia32/FspHelper.nasm b/IntelFsp2Pkg/FspSecCore/Ia32/FspHelper.nasm
index 00e953b4f100e5e7553f5a531606700342a3bc7e..43eac973a25f6bce83d8dc8ecd0da3b0a72b352b 100644 (file)
--- a/IntelFsp2Pkg/FspSecCore/Ia32/FspHelper.nasm
+++ b/IntelFsp2Pkg/FspSecCore/Ia32/FspHelper.nasm
@@ -14,22 +14,21 @@
     SECTION .text\r
 \r
 global ASM_PFX(FspInfoHeaderRelativeOff)\r
-ASM_PFX(FspInfoHeaderRelativeOff):\r
-   ;\r
-   ; This value will be pached by the build script\r
-   ;\r
-   DD    0x12345678\r
 \r
 global ASM_PFX(AsmGetFspBaseAddress)\r
 ASM_PFX(AsmGetFspBaseAddress):\r
-   mov   eax, ASM_PFX(AsmGetFspInfoHeader)\r
-   sub   eax, dword [ASM_PFX(FspInfoHeaderRelativeOff)]\r
+   call  ASM_PFX(AsmGetFspInfoHeader)\r
    add   eax, 0x1C\r
    mov   eax, dword [eax]\r
    ret\r
 \r
 global ASM_PFX(AsmGetFspInfoHeader)\r
 ASM_PFX(AsmGetFspInfoHeader):\r
-   mov   eax, ASM_PFX(AsmGetFspInfoHeader)\r
-   sub   eax, dword [ASM_PFX(FspInfoHeaderRelativeOff)]\r
+   call  ASM_PFX(NextInstruction)\r
+ASM_PFX(NextInstruction):\r
+   pop   eax\r
+   sub   eax, ASM_PFX(NextInstruction)\r
+   add   eax, ASM_PFX(AsmGetFspInfoHeader)\r
+   DB    02Dh                                               ; opcode of sub eax, imm32\r
+ASM_PFX(FspInfoHeaderRelativeOff):    DD    0x12345678      ; sub eax, FspInfoHeaderRelativeOff\r
    ret\r