/* startup.S - bootstrap GRUB itself */ /* * GRUB -- GRand Unified Bootloader * Copyright (C) 2006,2007,2009 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 .file "startup.S" .text .globl start, _start .code64 start: _start: jmp codestart /* * Compatibility version number * * These MUST be at byte offset 6 and 7 of the executable * DO NOT MOVE !!! */ . = _start + 0x6 .byte GRUB_BOOT_VERSION_MAJOR, GRUB_BOOT_VERSION_MINOR /* * This is a special data area 8 bytes from the beginning. */ . = _start + 0x8 VARIABLE(grub_prefix) /* to be filled by grub-mkimage */ /* * Leave some breathing room for the prefix. */ . = _start + 0x50 codestart: movq %rcx, EXT_C(grub_efi_image_handle)(%rip) movq %rdx, EXT_C(grub_efi_system_table)(%rip) call EXT_C(grub_main) ret