1/* linux/arch/arm/plat-s3c24xx/sleep.S
2 *
3 * Copyright (c) 2004 Simtec Electronics
4 *	Ben Dooks <ben@simtec.co.uk>
5 *
6 * S3C2410 Power Manager (Suspend-To-RAM) support
7 *
8 * Based on PXA/SA1100 sleep code by:
9 *	Nicolas Pitre, (c) 2002 Monta Vista Software Inc
10 *	Cliff Brake, (c) 2001
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
16 *
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20 * GNU General Public License for more details.
21 *
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
25*/
26
27#include <linux/linkage.h>
28#include <linux/serial_s3c.h>
29#include <asm/assembler.h>
30#include <mach/hardware.h>
31#include <mach/map.h>
32
33#include <mach/regs-gpio.h>
34#include <mach/regs-clock.h>
35
36/* CONFIG_DEBUG_RESUME is dangerous if your bootloader does not
37 * reset the UART configuration, only enable if you really need this!
38*/
39//#define CONFIG_DEBUG_RESUME
40
41	.text
42
43	/* sleep magic, to allow the bootloader to check for an valid
44	 * image to resume to. Must be the first word before the
45	 * s3c_cpu_resume entry.
46	*/
47
48	.word	0x2bedf00d
49
50	/* s3c_cpu_resume
51	 *
52	 * resume code entry for bootloader to call
53	*/
54
55ENTRY(s3c_cpu_resume)
56	mov	r0, #PSR_I_BIT | PSR_F_BIT | SVC_MODE
57	msr	cpsr_c, r0
58
59	@@ load UART to allow us to print the two characters for
60	@@ resume debug
61
62	mov	r2, #S3C24XX_PA_UART & 0xff000000
63	orr	r2, r2, #S3C24XX_PA_UART & 0xff000
64
65#if 0
66	/* SMDK2440 LED set */
67	mov	r14, #S3C24XX_PA_GPIO
68	ldr	r12, [ r14, #0x54 ]
69	bic	r12, r12, #3<<4
70	orr	r12, r12, #1<<7
71	str	r12, [ r14, #0x54 ]
72#endif
73
74#ifdef CONFIG_DEBUG_RESUME
75	mov	r3, #'L'
76	strb	r3, [ r2, #S3C2410_UTXH ]
771001:
78	ldrb	r14, [ r3, #S3C2410_UTRSTAT ]
79	tst	r14, #S3C2410_UTRSTAT_TXE
80	beq	1001b
81#endif /* CONFIG_DEBUG_RESUME */
82
83	b	cpu_resume
84