[ARM] 3986/1: H1940: suspend to RAM support
[pandora-kernel.git] / arch / arm / mach-s3c2410 / s3c2410-pm.c
1 /* linux/arch/arm/mach-s3c2410/s3c2410-pm.c
2  *
3  * Copyright (c) 2006 Simtec Electronics
4  *      Ben Dooks <ben@simtec.co.uk>
5  *
6  * S3C2410 (and compatible) Power Manager (Suspend-To-RAM) 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/init.h>
24 #include <linux/suspend.h>
25 #include <linux/errno.h>
26 #include <linux/time.h>
27 #include <linux/sysdev.h>
28
29 #include <asm/hardware.h>
30 #include <asm/io.h>
31
32 #include <asm/mach-types.h>
33
34 #include <asm/arch/regs-gpio.h>
35 #include <asm/arch/h1940.h>
36
37 #include "cpu.h"
38 #include "pm.h"
39
40 #ifdef CONFIG_S3C2410_PM_DEBUG
41 extern void pm_dbg(const char *fmt, ...);
42 #define DBG(fmt...) pm_dbg(fmt)
43 #else
44 #define DBG(fmt...) printk(KERN_DEBUG fmt)
45 #endif
46
47 static void s3c2410_pm_prepare(void)
48 {
49         /* ensure at least GSTATUS3 has the resume address */
50
51         __raw_writel(virt_to_phys(s3c2410_cpu_resume), S3C2410_GSTATUS3);
52
53         DBG("GSTATUS3 0x%08x\n", __raw_readl(S3C2410_GSTATUS3));
54         DBG("GSTATUS4 0x%08x\n", __raw_readl(S3C2410_GSTATUS4));
55
56         if (machine_is_h1940()) {
57                 void *base = phys_to_virt(H1940_SUSPEND_CHECK);
58                 unsigned long ptr;
59                 unsigned long calc = 0;
60
61                 /* generate check for the bootloader to check on resume */
62
63                 for (ptr = 0; ptr < 0x40000; ptr += 0x400)
64                         calc += __raw_readl(base+ptr);
65
66                 __raw_writel(calc, phys_to_virt(H1940_SUSPEND_CHECKSUM));
67         }
68
69         if ( machine_is_aml_m5900() )
70                 s3c2410_gpio_setpin(S3C2410_GPF2, 1);
71
72 }
73
74 int s3c2410_pm_resume(struct sys_device *dev)
75 {
76         unsigned long tmp;
77
78         /* unset the return-from-sleep flag, to ensure reset */
79
80         tmp = __raw_readl(S3C2410_GSTATUS2);
81         tmp &= S3C2410_GSTATUS2_OFFRESET;
82         __raw_writel(tmp, S3C2410_GSTATUS2);
83
84         if ( machine_is_aml_m5900() )
85                 s3c2410_gpio_setpin(S3C2410_GPF2, 0);
86
87         return 0;
88 }
89
90 static int s3c2410_pm_add(struct sys_device *dev)
91 {
92         pm_cpu_prep = s3c2410_pm_prepare;
93         pm_cpu_sleep = s3c2410_cpu_suspend;
94
95         return 0;
96 }
97
98 static struct sysdev_driver s3c2410_pm_driver = {
99         .add            = s3c2410_pm_add,
100         .resume         = s3c2410_pm_resume,
101 };
102
103 /* register ourselves */
104
105 static int __init s3c2410_pm_drvinit(void)
106 {
107         return sysdev_driver_register(&s3c2410_sysclass, &s3c2410_pm_driver);
108 }
109
110 arch_initcall(s3c2410_pm_drvinit);
111
112 static struct sysdev_driver s3c2440_pm_driver = {
113         .add            = s3c2410_pm_add,
114         .resume         = s3c2410_pm_resume,
115 };
116
117 static int __init s3c2440_pm_drvinit(void)
118 {
119         return sysdev_driver_register(&s3c2440_sysclass, &s3c2440_pm_driver);
120 }
121
122 arch_initcall(s3c2440_pm_drvinit);
123
124 static struct sysdev_driver s3c2442_pm_driver = {
125         .add            = s3c2410_pm_add,
126         .resume         = s3c2410_pm_resume,
127 };
128
129 static int __init s3c2442_pm_drvinit(void)
130 {
131         return sysdev_driver_register(&s3c2442_sysclass, &s3c2442_pm_driver);
132 }
133
134 arch_initcall(s3c2442_pm_drvinit);