CloverBootloader/UefiCpuPkg/ResetVector/Vtf0/Ia16/ResetVectorVtf0.asm

66 lines
1.5 KiB
NASM

;------------------------------------------------------------------------------
; @file
; First code executed by processor after resetting.
;
; Copyright (c) 2008 - 2014, Intel Corporation. All rights reserved.<BR>
; SPDX-License-Identifier: BSD-2-Clause-Patent
;
;------------------------------------------------------------------------------
BITS 16
ALIGN 16
;
; Pad the image size to 4k when page tables are in VTF0
;
; If the VTF0 image has page tables built in, then we need to make
; sure the end of VTF0 is 4k above where the page tables end.
;
; This is required so the page tables will be 4k aligned when VTF0 is
; located just below 0x100000000 (4GB) in the firmware device.
;
%ifdef ALIGN_TOP_TO_4K_FOR_PAGING
TIMES (0x1000 - ($ - EndOfPageTables) - 0x20) DB 0
%endif
applicationProcessorEntryPoint:
;
; Application Processors entry point
;
; GenFv generates code aligned on a 4k boundary which will jump to this
; location. (0xffffffe0) This allows the Local APIC Startup IPI to be
; used to wake up the application processors.
;
jmp EarlyApInitReal16
ALIGN 8
DD 0
;
; The VTF signature
;
; VTF-0 means that the VTF (Volume Top File) code does not require
; any fixups.
;
vtfSignature:
DB 'V', 'T', 'F', 0
ALIGN 16
resetVector:
;
; Reset Vector
;
; This is where the processor will begin execution
;
nop
nop
jmp EarlyBspInitReal16
ALIGN 16
fourGigabytes: