Diffstat (limited to 'arch/x86/boot/boot_main.S')
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diff --git a/arch/x86/boot/boot_main.S b/arch/x86/boot/boot_main.S
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+ * Copyright (C) 2009 Juergen Beisert, Pengutronix
+ * This code was inspired by the GRUB2 project.
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ * @file
+ * @brief Common boot sector main routine to be entered by the BIOS
+ * @fn void _start(void)
+ * @brief Fix segment:offset settings of some buggy BIOSs
+ .file "boot_main.S"
+ .extern real_start
+ .section .boot_start, "ax"
+ .type _start, @function
+ * The BIOS loads this code to address 0x00007c00.
+ * The code should be called with CS:IP 0:0x7c00 (hopefully).
+ .globl _start
+ cli /* we're not safe here! */
+ * It seems there are implementations in the wild which call this
+ * code with CS:IP 0x07C0:0000 instead. We fix it immediately.
+ ljmp $0, $real_start
+ .size _start, .-_start