xref: /openbmc/linux/arch/arm/mach-exynos/sleep.S (revision d2999e1b)
1/*
2 * Copyright (c) 2013 Samsung Electronics Co., Ltd.
3 *		http://www.samsung.com
4 *
5 * Exynos low-level resume code
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 * GNU General Public License for more details.
16 */
17
18#include <linux/linkage.h>
19
20#define CPU_MASK	0xff0ffff0
21#define CPU_CORTEX_A9	0x410fc090
22
23	/*
24	 * The following code is located into the .data section. This is to
25	 * allow l2x0_regs_phys to be accessed with a relative load while we
26	 * can't rely on any MMU translation. We could have put l2x0_regs_phys
27	 * in the .text section as well, but some setups might insist on it to
28	 * be truly read-only. (Reference from: arch/arm/kernel/sleep.S)
29	 */
30	.data
31	.align
32
33	/*
34	 * sleep magic, to allow the bootloader to check for an valid
35	 * image to resume to. Must be the first word before the
36	 * exynos_cpu_resume entry.
37	 */
38
39	.word	0x2bedf00d
40
41	/*
42	 * exynos_cpu_resume
43	 *
44	 * resume code entry for bootloader to call
45	 */
46
47ENTRY(exynos_cpu_resume)
48#ifdef CONFIG_CACHE_L2X0
49	mrc	p15, 0, r0, c0, c0, 0
50	ldr	r1, =CPU_MASK
51	and	r0, r0, r1
52	ldr	r1, =CPU_CORTEX_A9
53	cmp	r0, r1
54	bleq	l2c310_early_resume
55#endif
56	b	cpu_resume
57ENDPROC(exynos_cpu_resume)
58