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/* @r{boot.S - bootstrap the kernel} */
/* @r{Copyright (C) 1999, 2001 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.} */
#define ASM 1
#include <multiboot.h>
.text
.globl start, _start
start:
_start:
jmp multiboot_entry
/* @r{Align 32 bits boundary.} */
.align 4
/* @r{Multiboot header.} */
multiboot_header:
/* @r{magic} */
.long MULTIBOOT_HEADER_MAGIC
/* @r{flags} */
.long MULTIBOOT_HEADER_FLAGS
/* @r{checksum} */
.long -(MULTIBOOT_HEADER_MAGIC + MULTIBOOT_HEADER_FLAGS)
#ifndef __ELF__
/* @r{header_addr} */
.long multiboot_header
/* @r{load_addr} */
.long _start
/* @r{load_end_addr} */
.long _edata
/* @r{bss_end_addr} */
.long _end
/* @r{entry_addr} */
.long multiboot_entry
#endif /* @r{! __ELF__} */
multiboot_entry:
/* @r{Initialize the stack pointer.} */
movl $(stack + STACK_SIZE), %esp
/* @r{Reset EFLAGS.} */
pushl $0
popf
/* @r{Push the pointer to the Multiboot information structure.} */
pushl %ebx
/* @r{Push the magic value.} */
pushl %eax
/* @r{Now enter the C main function...} */
call EXT_C(cmain)
/* @r{Halt.} */
pushl $halt_message
call EXT_C(printf)
loop: hlt
jmp loop
halt_message:
.asciz "Halted."
/* @r{Our stack area.} */
.comm stack, STACK_SIZE
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