audk/IntelFsp2Pkg/Library/SecFspSecPlatformLibNull/Ia32/Flat32.s

111 lines
3.3 KiB
ArmAsm

#------------------------------------------------------------------------------
#
# Copyright (c) 2015 - 2016, 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.
#
# Abstract:
#
# This is the code that goes from real-mode to protected mode.
# It consumes the reset vector, configures the stack.
#
#------------------------------------------------------------------------------
#
# Contrary to the name, this file contains 16 bit code as well.
#
.text
ASM_GLOBAL ASM_PFX(SecPlatformInit)
ASM_PFX(SecPlatformInit):
movd %mm7, %esi # restore ESP from MM7
jmp *%esi
#----------------------------------------------------------------------------
#
# Procedure: ProtectedModeEntryPoint
#
# Input: Executing in 32 Bit Protected (flat) mode
# cs: 0-4GB
# ds: 0-4GB
# es: 0-4GB
# fs: 0-4GB
# gs: 0-4GB
# ss: 0-4GB
#
# Output: This function never returns
#
# Destroys:
# ecx
# edi
# esi
# esp
#
# Description:
# Perform any essential early platform initilaisation
# Setup a stack
#
#----------------------------------------------------------------------------
ProtectedModeEntryPoint:
#
# Dummy function. Consume 2 API to make sure they can be linked.
#
movl ASM_PFX(TempRamInitApi), %eax
#
# Should never return
#
jmp . #'$'
#
# ROM-based Global-Descriptor Table for the PEI Phase
#
.align 16
#
# GDT[0]: 000h: Null entry, never used.
#
.equ NULL_SEL, . - GDT_BASE # Selector [0]
GDT_BASE:
BootGdtTable:
.long 0
.long 0
#
# Linear code segment descriptor
#
.equ LINEAR_CODE_SEL, . - GDT_BASE # Selector [08h]
.word 0xFFFF # limit 0FFFFh
.word 0 # base 0
.byte 0
.byte 0x9B # present, ring 0, data, expand-up, not-writable
.byte 0xCF # page-granular, 32-bit
.byte 0
#
# System data segment descriptor
#
.equ SYS_DATA_SEL, . - GDT_BASE # Selector [010h]
.word 0xFFFF # limit 0FFFFh
.word 0 # base 0
.byte 0
.byte 0x93 # present, ring 0, data, expand-up, not-writable
.byte 0xCF # page-granular, 32-bit
.byte 0
.equ GDT_SIZE, . - BootGdtTable # Size, in bytes
#
# GDT Descriptor
#
GdtDesc: # GDT descriptor
.word GDT_SIZE - 1
.long BootGdtTable
ProtectedModeEntryLinearAddress:
ProtectedModeEntryLinearOffset:
.long ProtectedModeEntryPoint
.word LINEAR_CODE_SEL