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1/*
2 * Startup code for use with the u-boot bootloader.
3 *
4 * Copyright (C) 2004-2006 Atmel Corporation
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10#include <asm/setup.h>
11
12	/*
13	 * The kernel is loaded where we want it to be and all caches
14	 * have just been flushed. We get two parameters from u-boot:
15	 *
16	 * r12 contains a magic number (ATAG_MAGIC)
17	 * r11 points to a tag table providing information about
18	 *     the system.
19	 */
20	.section .init.text,"ax"
21	.global _start
22_start:
23	/* Check if the boot loader actually provided a tag table */
24	lddpc	r0, magic_number
25	cp.w	r12, r0
26	brne	no_tag_table
27
28	/* Initialize .bss */
29	lddpc	r2, bss_start_addr
30	lddpc   r3, end_addr
31	mov	r0, 0
32	mov	r1, 0
331:      st.d    r2++, r0
34	cp      r2, r3
35	brlo    1b
36
37	/*
38	 * Save the tag table address for later use. This must be done
39	 * _after_ .bss has been initialized...
40	 */
41	lddpc	r0, tag_table_addr
42	st.w	r0[0], r11
43
44	/* Jump to loader-independent setup code */
45	rjmp	kernel_entry
46
47	.align	2
48magic_number:
49	.long	ATAG_MAGIC
50tag_table_addr:
51	.long	bootloader_tags
52bss_start_addr:
53	.long   __bss_start
54end_addr:
55	.long   _end
56
57no_tag_table:
58	sub	r12, pc, (. - 2f)
59	bral	panic
602:	.asciz	"Boot loader didn't provide correct magic number\n"
61