53 lines
1.2 KiB
ArmAsm
53 lines
1.2 KiB
ArmAsm
/*
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* Copyright (C) 2009 Juergen Beisert, Pengutronix
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*
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* This code was inspired by the GRUB2 project.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation; either version 2 of
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* the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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*
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*/
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/**
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* @file
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* @brief Common boot sector main routine to be entered by the BIOS
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*/
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/**
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* @fn void _start(void)
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*
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* @brief Fix segment:offset settings of some buggy BIOSs
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*/
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.file "boot_main.S"
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.code16
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.extern real_start
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.section .boot_start, "ax"
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.type _start, @function
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/*
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* The BIOS loads this code to address 0x00007c00.
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* The code should be called with CS:IP 0:0x7c00 (hopefully).
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*/
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.globl _start
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_start:
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cli /* we're not safe here! */
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/*
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* It seems there are implementations in the wild which call this
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* code with CS:IP 0x07C0:0000 instead. We fix it immediately.
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*/
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ljmp $0, $real_start
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.size _start, .-_start
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