arch/arm/mach-s3c2416/pm.c

   1 /* linux/arch/arm/mach-s3c2416/pm.c
   2  *
   3  * Copyright (c) 2010 Samsung Electronics Co., Ltd.
   4  *              http://www.samsung.com
   5  *
   6  * S3C2416 - PM support (Based on Ben Dooks' S3C2412 PM 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 version 2 as
  10  * published by the Free Software Foundation.
  11 */
  12
  13 #include <linux/device.h>
  14 #include <linux/syscore_ops.h>
  15 #include <linux/io.h>
  16
  17 #include <asm/cacheflush.h>
  18
  19 #include <mach/regs-power.h>
  20 #include <mach/regs-s3c2443-clock.h>
  21
  22 #include <plat/cpu.h>
  23 #include <plat/pm.h>
  24
  25 extern void s3c2412_sleep_enter(void);
  26
  27 static int s3c2416_cpu_suspend(unsigned long arg)
  28 {
  29         /* enable wakeup sources regardless of battery state */
  30         __raw_writel(S3C2443_PWRCFG_SLEEP, S3C2443_PWRCFG);
  31
  32         /* set the mode as sleep, 2BED represents "Go to BED" */
  33         __raw_writel(0x2BED, S3C2443_PWRMODE);
  34
  35         s3c2412_sleep_enter();
  36
  37         panic("sleep resumed to originator?");
  38 }
  39
  40 static void s3c2416_pm_prepare(void)
  41 {
  42         /*
  43          * write the magic value u-boot uses to check for resume into
  44          * the INFORM0 register, and ensure INFORM1 is set to the
  45          * correct address to resume from.
  46          */
  47         __raw_writel(0x2BED, S3C2412_INFORM0);
  48         __raw_writel(virt_to_phys(s3c_cpu_resume), S3C2412_INFORM1);
  49 }
  50
  51 static int s3c2416_pm_add(struct device *dev, struct subsys_interface *sif)
  52 {
  53         pm_cpu_prep = s3c2416_pm_prepare;
  54         pm_cpu_sleep = s3c2416_cpu_suspend;
  55
  56         return 0;
  57 }
  58
  59 static struct subsys_interface s3c2416_pm_interface = {
  60         .name           = "s3c2416_pm",
  61         .subsys         = &s3c2416_subsys,
  62         .add_dev        = s3c2416_pm_add,
  63 };
  64
  65 static __init int s3c2416_pm_init(void)
  66 {
  67         return subsys_interface_register(&s3c2416_pm_interface);
  68 }
  69
  70 arch_initcall(s3c2416_pm_init);
  71
  72
  73 static void s3c2416_pm_resume(void)
  74 {
  75         /* unset the return-from-sleep amd inform flags */
  76         __raw_writel(0x0, S3C2443_PWRMODE);
  77         __raw_writel(0x0, S3C2412_INFORM0);
  78         __raw_writel(0x0, S3C2412_INFORM1);
  79 }
  80
  81 struct syscore_ops s3c2416_pm_syscore_ops = {
  82         .resume         = s3c2416_pm_resume,
  83 };