1/* linux/arch/arm/mach-s3c2412/sleep.S
2 *
3 * Copyright (c) 2007 Simtec Electronics
4 *	Ben Dooks <ben@simtec.co.uk>
5 *
6 * S3C2412 Power Manager low-level sleep support
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
21*/
22
23#include <linux/linkage.h>
24#include <asm/assembler.h>
25#include <mach/hardware.h>
26#include <mach/map.h>
27
28#include <mach/regs-irq.h>
29
30	.text
31
32	.global	s3c2412_sleep_enter
33
34s3c2412_sleep_enter:
35	mov	r0, #0			/* argument for coprocessors */
36	ldr	r1, =S3C2410_INTPND
37	ldr	r2, =S3C2410_SRCPND
38	ldr	r3, =S3C2410_EINTPEND
39
40	teq	r0, r0
41	bl	s3c2412_sleep_enter1
42	teq	pc, r0
43	bl	s3c2412_sleep_enter1
44
45	.align	5
46
47	/* this is called twice, first with the Z flag to ensure that the
48	 * instructions have been loaded into the cache, and the second
49	 * time to try and suspend the system.
50	*/
51s3c2412_sleep_enter1:
52	mcr	p15, 0, r0, c7, c10, 4
53	mcrne	p15, 0, r0, c7, c0, 4
54
55	/* if we return from here, it is because an interrupt was
56	 * active when we tried to shutdown. Try and ack the IRQ and
57	 * retry, as simply returning causes the system to lock.
58	*/
59
60	ldrne	r9, [ r1 ]
61	strne	r9, [ r1 ]
62	ldrne	r9, [ r2 ]
63	strne	r9, [ r2 ]
64	ldrne	r9, [ r3 ]
65	strne	r9, [ r3 ]
66	bne	s3c2412_sleep_enter1
67
68	mov	pc, r14
69