/* * GRUB -- GRand Unified Bootloader * Copyright (C) 1999,2000,2001,2002,2003,2005,2006,2007,2008,2009 Free Software Foundation, Inc. * * GRUB 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 3 of the License, or * (at your option) any later version. * * GRUB 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 GRUB. If not, see . */ #include #include #include #include #include .text .code16 .globl _start _start: /* Disable interrupts. */ cli jmp 1f . = _start + GRUB_BOOT_MACHINE_CORE_ENTRY_ADDR VARIABLE(grub_core_entry_addr) .long 0 1: /* Process VGA rom. */ call $0xc000, $0x3 /* Set up %ds, %ss, and %es. */ xorw %ax, %ax movw %ax, %ds movw %ax, %ss movw %ax, %es /* Set up the real mode stack. */ movl $GRUB_MEMORY_MACHINE_REAL_STACK, %esp /* Transition to protected mode. We use pushl to force generation of a flat return address. */ pushl $1f DATA32 jmp real_to_prot .code32 1: movl grub_core_entry_addr, %edx jmp *%edx #include "../../../kern/i386/realmode.S" /* Intel, in its infinite wisdom, decided to put the i8086 entry point *right here* and this is why we need this kludge. */ . = GRUB_BOOT_MACHINE_SIZE - 16 .code16 jmp _start . = GRUB_BOOT_MACHINE_SIZE