start.S revision 1.1
11.1Snonaka/*	$NetBSD: start.S,v 1.1 2017/01/24 11:09:14 nonaka Exp $	*/
21.1Snonaka
31.1Snonaka/*-
41.1Snonaka * Copyright (c) 2008-2010 Rui Paulo <rpaulo@FreeBSD.org>
51.1Snonaka * All rights reserved.
61.1Snonaka *
71.1Snonaka * Redistribution and use in source and binary forms, with or without
81.1Snonaka * modification, are permitted provided that the following conditions
91.1Snonaka * are met:
101.1Snonaka * 1. Redistributions of source code must retain the above copyright
111.1Snonaka *    notice, this list of conditions and the following disclaimer.
121.1Snonaka * 2. Redistributions in binary form must reproduce the above copyright
131.1Snonaka *    notice, this list of conditions and the following disclaimer in the
141.1Snonaka *    documentation and/or other materials provided with the distribution.
151.1Snonaka *
161.1Snonaka * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
171.1Snonaka * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
181.1Snonaka * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
191.1Snonaka * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
201.1Snonaka * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
211.1Snonaka * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
221.1Snonaka * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
231.1Snonaka * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
241.1Snonaka * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
251.1Snonaka * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
261.1Snonaka * SUCH DAMAGE.
271.1Snonaka *
281.1Snonaka *	$FreeBSD: head/sys/boot/efi/loader/arch/i386/start.S 282728 2015-05-10 13:30:21Z ian $
291.1Snonaka */
301.1Snonaka
311.1Snonaka#include <machine/asm.h>
321.1Snonaka
331.1Snonaka	.text
341.1Snonaka	.align	16
351.1Snonaka
361.1Snonaka/*
371.1Snonaka * EFI entry point.
381.1Snonaka * _start(EFI_IMAGE image_handle, EFI_SYSTEM_TABLE *system_table);
391.1Snonaka *
401.1Snonaka * We calculate the base address along with _DYNAMIC, relocate us and finally
411.1Snonaka * pass control to efi_main.
421.1Snonaka */
431.1Snonaka
441.1SnonakaENTRY(_start)
451.1Snonaka	pushl	%ebp
461.1Snonaka	movl	%esp, %ebp
471.1Snonaka
481.1Snonaka	pushl	12(%ebp)	/* image_handle */
491.1Snonaka	pushl	8(%ebp)		/* system_table */
501.1Snonaka	call	0f
511.1Snonaka0:	popl	%eax
521.1Snonaka	movl	%eax, %ebx
531.1Snonaka	addl	$ImageBase-0b, %eax
541.1Snonaka	addl	$_DYNAMIC-0b, %ebx
551.1Snonaka	pushl	%ebx		/* dynamic */
561.1Snonaka	pushl	%eax		/* ImageBase */
571.1Snonaka	call	_C_LABEL(self_reloc)
581.1Snonaka	popl	%ebx		/* remove ImageBase from the stack */
591.1Snonaka	popl	%ebx		/* remove dynamic from the stack */
601.1Snonaka	call	_C_LABEL(efi_main)
611.1Snonaka1:	leave
621.1Snonaka	ret
631.1SnonakaEND(_start)
641.1Snonaka
651.1Snonaka	/*
661.1Snonaka	 * hand-craft a dummy .reloc section so EFI knows it's a relocatable
671.1Snonaka	 * executable:
681.1Snonaka	 */
691.1Snonaka
701.1Snonaka	.data
711.1Snonaka	.section .reloc, "a"
721.1Snonaka	.long   0
731.1Snonaka	.long   10
741.1Snonaka	.word   0
75