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/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2000 Free Software Foundation, Inc.
*
* 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/*
* MultiBoot Header description
*/
struct multiboot_header
{
/* Must be MULTIBOOT_MAGIC - see below. */
uint32_t magic;
/* Feature flags - see below. */
uint32_t flags;
/*
* Checksum
*
* The above fields plus this one must equal 0 mod 2^32.
*/
uint32_t checksum;
/* These are only valid if MULTIBOOT_AOUT_KLUDGE is set. */
uint32_t header_addr;
uint32_t load_addr;
uint32_t load_end_addr;
uint32_t bss_end_addr;
uint32_t entry_addr;
/* These are only valid if MULTIBOOT_VIDEO_MODE is set. */
uint32_t mode_type;
uint32_t width;
uint32_t height;
uint32_t depth;
};
/*
* The entire multiboot_header must be contained
* within the first MULTIBOOT_SEARCH bytes of the kernel image.
*/
#define MULTIBOOT_SEARCH 8192
#define MULTIBOOT_FOUND(addr, len) \
(! ((addr) & 0x3) \
&& (len) >= 12 \
&& *((int *) (addr)) == MULTIBOOT_MAGIC \
&& ! (*((uint32_t *) (addr)) + *((uint32_t *) (addr + 4)) \
+ *((uint32_t *) (addr + 8))) \
&& (! (MULTIBOOT_AOUT_KLUDGE & *((int *) (addr + 4))) || (len) >= 32) \
&& (! (MULTIBOOT_VIDEO_MODE & *((int *) (addr + 4))) || (len) >= 48))
/* Magic value identifying the multiboot_header. */
#define MULTIBOOT_MAGIC 0x1BADB002
/*
* Features flags for 'flags'.
* If a boot loader sees a flag in MULTIBOOT_MUSTKNOW set
* and it doesn't understand it, it must fail.
*/
#define MULTIBOOT_MUSTKNOW 0x0000FFFF
/* currently unsupported flags... this is a kind of version number. */
#define MULTIBOOT_UNSUPPORTED 0x0000FFF8
/* Align all boot modules on i386 page (4KB) boundaries. */
#define MULTIBOOT_PAGE_ALIGN 0x00000001
/* Must pass memory information to OS. */
#define MULTIBOOT_MEMORY_INFO 0x00000002
/* Must pass video information to OS. */
#define MULTIBOOT_VIDEO_MODE 0x00000004
/* This flag indicates the use of the address fields in the header. */
#define MULTIBOOT_AOUT_KLUDGE 0x00010000
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