xref: /linux/arch/xtensa/boot/boot-elf/bootstrap.S (revision da1d9caf95def6f0320819cf941c9fd1069ba9e1)
1/*
2 * arch/xtensa/boot/boot-elf/bootstrap.S
3 *
4 * Low-level exception handling
5 *
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License.  See the file "COPYING" in the main directory of this archive
8 * for more details.
9 *
10 * Copyright (C) 2004 - 2013 by Tensilica Inc.
11 *
12 * Chris Zankel <chris@zankel.net>
13 * Marc Gauthier <marc@tensilica.com>
14 * Piet Delaney <piet@tensilica.com>
15 */
16
17#include <asm/bootparam.h>
18#include <asm/initialize_mmu.h>
19#include <asm/vectors.h>
20#include <linux/linkage.h>
21
22	.section	.ResetVector.text, "ax"
23	.global         _ResetVector
24	.global         reset
25
26_ResetVector:
27	_j _SetupMMU
28
29	.begin  no-absolute-literals
30	.literal_position
31
32#ifdef CONFIG_PARSE_BOOTPARAM
33	.align 4
34_bootparam:
35	.short	BP_TAG_FIRST
36	.short	4
37	.long	BP_VERSION
38	.short	BP_TAG_LAST
39	.short	0
40	.long	0
41#endif
42
43	.align  4
44_SetupMMU:
45#if XCHAL_HAVE_WINDOWED
46	movi	a0, 0
47	wsr	a0, windowbase
48	rsync
49	movi	a0, 1
50	wsr	a0, windowstart
51	rsync
52#endif
53	movi	a0, 0x1F
54	wsr	a0, ps
55	rsync
56
57#ifndef CONFIG_INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX
58	initialize_mmu
59#endif
60
61	rsil    a0, XCHAL_DEBUGLEVEL-1
62	rsync
63reset:
64#if defined(CONFIG_INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX) && \
65	XCHAL_HAVE_PTP_MMU && XCHAL_HAVE_SPANNING_WAY
66	movi	a0, CONFIG_KERNEL_LOAD_ADDRESS
67#else
68	movi	a0, KERNELOFFSET
69#endif
70#ifdef CONFIG_PARSE_BOOTPARAM
71	movi	a2, _bootparam
72#else
73	movi	a2, 0
74#endif
75	movi	a3, 0
76	movi	a4, 0
77	jx      a0
78
79	.end    no-absolute-literals
80