From b9e702c3c9bfe7bfb6bbcff44603add64e1787bf Mon Sep 17 00:00:00 2001 From: "Duggapu, Chinni B" Date: Mon, 7 Nov 2022 14:47:31 +0800 Subject: UefiCpuPkg/ResetVector:Add Option to reserve 4K region at 4GB REF: https://bugzilla.tianocore.org/show_bug.cgi?id=4140 Some implementations may need to keep the initial Reset code to be separated out from rest of the code.This request is to add padding at lower 4K region below 4 GB which will result having only few jmp instructions and data at that region. Reviewed-by: Ray Ni Signed-off-by: Duggapu Chinni B --- UefiCpuPkg/ResetVector/Vtf0/Ia16/ResetVectorVtf0.asm | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'UefiCpuPkg/ResetVector') diff --git a/UefiCpuPkg/ResetVector/Vtf0/Ia16/ResetVectorVtf0.asm b/UefiCpuPkg/ResetVector/Vtf0/Ia16/ResetVectorVtf0.asm index 7538192876..fe5bbea803 100644 --- a/UefiCpuPkg/ResetVector/Vtf0/Ia16/ResetVectorVtf0.asm +++ b/UefiCpuPkg/ResetVector/Vtf0/Ia16/ResetVectorVtf0.asm @@ -21,7 +21,15 @@ ALIGN 16 ; located just below 0x100000000 (4GB) in the firmware device. ; %ifdef ALIGN_TOP_TO_4K_FOR_PAGING - TIMES (0x1000 - ($ - EndOfPageTables) - 0x20) DB 0 + TIMES (0x1000 - ($ - EndOfPageTables)) DB 0 +; +; Pad the VTF0 Reset code for Bsp & Ap to 4k aligned block. +; Some implementations may need to keep the initial Reset code +; to be separated out from rest of the code. +; This padding will make sure lower 4K region below 4 GB may +; only contains few jmp instructions and data. +; + TIMES (0x1000 - 0x20) DB 0 %endif applicationProcessorEntryPoint: -- cgit v1.2.3