xref: /freebsd/stand/efi/loader/arch/i386/start.S (revision e8d8bef961a50d4dc22501cde4fb9fb0be1b2532)
1/*-
2 * Copyright (c) 2008-2010 Rui Paulo <rpaulo@FreeBSD.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 *	$FreeBSD$
27 */
28
29	.text
30
31#include <machine/asm.h>
32
33#define EFI_SUCCESS		0
34
35/*
36 * EFI entry point.
37 * _start(EFI_IMAGE image_handle, EFI_SYSTEM_TABLE *system_table);
38 *
39 * We calculate the base address along with _DYNAMIC, relocate us and finally
40 * pass control to efi_main.
41 */
42
43ENTRY(_start)
44	pushl	%ebp
45	movl	%esp, %ebp
46
47	pushl	12(%ebp)	/* image_handle */
48	pushl	8(%ebp)		/* system_table */
49	call	0f
500:	popl	%eax
51	movl	%eax, %ebx
52	addl	$ImageBase-0b, %eax
53	addl	$_DYNAMIC-0b, %ebx
54	pushl	%ebx		/* dynamic */
55	pushl	%eax		/* ImageBase */
56	call	self_reloc
57	popl	%ebx		/* remove ImageBase from the stack */
58	popl	%ebx		/* remove dynamic from the stack */
59	call	efi_main
601:	leave
61	ret
62END(_start)
63
64	.data
65	.section .reloc, "a"
66	.long	0
67	.long	10
68	.word	0
69