1/* 2 * GRUB -- GRand Unified Bootloader 3 * Copyright (C) 2000 Free Software Foundation, Inc. 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License as published by 7 * the Free Software Foundation; either version 2 of the License, or 8 * (at your option) any later version. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write to the Free Software 17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 18 */ 19 20 .file "pxeloader.S" 21 .text 22 23 /* Start with the prehistoric environment... */ 24 .code16 25 26 /* Let's go */ 27.globl _start; _start: 28 movw %sp, %bp 29 movw %ss:4(%bp), %ax 30 pushw %ax 31 movw %ss:6(%bp), %ax 32 pushw %ax 33 call 1f 341: popw %bx 35 36 /* Save !PXE address */ 37 popw %ax 38 movw %ax, %cs:(pxeseg-1b)(%bx) 39 popw %ax 40 movw %ax, %cs:(pxeoff-1b)(%bx) 41 movw %ax, %bx 42 43 /* Jump to the real world */ 44 ljmp $0, $0x8200 45 46 . = _start + 0x7C80 - 0x7C00 47pxeseg: .word 0 48pxeoff: .word 0 49 50 /* This region is a junk. Do you say that this is wasteful? 51 But I like that the memory layout of the body is consistent 52 among different stage2s rather than scamping just for 1.5KB. */ 53 . = _start + 0x8200 - 0x7C00 - 1 54 .byte 0 55