LXR linux/arch/arm/mach-s3c/pm.c

   1// SPDX-License-Identifier: GPL-2.0
   2//
   3// Copyright 2008 Openmoko, Inc.
   4// Copyright 2004-2008 Simtec Electronics
   5//      Ben Dooks <ben@simtec.co.uk>
   6//      http://armlinux.simtec.co.uk/
   7//
   8// S3C common power management (suspend to ram) support.
   9
  10#include <linux/init.h>
  11#include <linux/suspend.h>
  12#include <linux/errno.h>
  13#include <linux/delay.h>
  14#include <linux/of.h>
  15#include <linux/serial_s3c.h>
  16#include <linux/io.h>
  17
  18#include <asm/cacheflush.h>
  19#include <asm/suspend.h>
  20
  21#include "map.h"
  22#include "regs-clock.h"
  23#include "regs-irq.h"
  24#include <mach/irqs.h>
  25
  26#include <asm/irq.h>
  27
  28#include "cpu.h"
  29#include "pm.h"
  30#include "pm-core.h"
  31
  32/* for external use */
  33
  34unsigned long s3c_pm_flags;
  35
  36/* The IRQ ext-int code goes here, it is too small to currently bother
  37 * with its own file. */
  38
  39unsigned long s3c_irqwake_intmask       = 0xffffffffL;
  40unsigned long s3c_irqwake_eintmask      = 0xffffffffL;
  41
  42int s3c_irqext_wake(struct irq_data *data, unsigned int state)
  43{
  44        unsigned long bit = 1L << IRQ_EINT_BIT(data->irq);
  45
  46        if (!(s3c_irqwake_eintallow & bit))
  47                return -ENOENT;
  48
  49        printk(KERN_INFO "wake %s for irq %d\n",
  50               state ? "enabled" : "disabled", data->irq);
  51
  52        if (!state)
  53                s3c_irqwake_eintmask |= bit;
  54        else
  55                s3c_irqwake_eintmask &= ~bit;
  56
  57        return 0;
  58}
  59
  60void (*pm_cpu_prep)(void);
  61int (*pm_cpu_sleep)(unsigned long);
  62
  63#define any_allowed(mask, allow) (((mask) & (allow)) != (allow))
  64
  65/* s3c_pm_enter
  66 *
  67 * central control for sleep/resume process
  68*/
  69
  70static int s3c_pm_enter(suspend_state_t state)
  71{
  72        int ret;
  73        /* ensure the debug is initialised (if enabled) */
  74        s3c_pm_debug_init_uart();
  75
  76        S3C_PMDBG("%s(%d)\n", __func__, state);
  77
  78        if (pm_cpu_prep == NULL || pm_cpu_sleep == NULL) {
  79                printk(KERN_ERR "%s: error: no cpu sleep function\n", __func__);
  80                return -EINVAL;
  81        }
  82
  83        /* check if we have anything to wake-up with... bad things seem
  84         * to happen if you suspend with no wakeup (system will often
  85         * require a full power-cycle)
  86        */
  87
  88        if (!of_have_populated_dt() &&
  89            !any_allowed(s3c_irqwake_intmask, s3c_irqwake_intallow) &&
  90            !any_allowed(s3c_irqwake_eintmask, s3c_irqwake_eintallow)) {
  91                printk(KERN_ERR "%s: No wake-up sources!\n", __func__);
  92                printk(KERN_ERR "%s: Aborting sleep\n", __func__);
  93                return -EINVAL;
  94        }
  95
  96        /* save all necessary core registers not covered by the drivers */
  97
  98        if (!of_have_populated_dt()) {
  99                samsung_pm_save_gpios();
 100                samsung_pm_saved_gpios();
 101        }
 102
 103        s3c_pm_save_uarts(soc_is_s3c2410());
 104        s3c_pm_save_core();
 105
 106        /* set the irq configuration for wake */
 107
 108        s3c_pm_configure_extint();
 109
 110        S3C_PMDBG("sleep: irq wakeup masks: %08lx,%08lx\n",
 111            s3c_irqwake_intmask, s3c_irqwake_eintmask);
 112
 113        s3c_pm_arch_prepare_irqs();
 114
 115        /* call cpu specific preparation */
 116
 117        pm_cpu_prep();
 118
 119        /* flush cache back to ram */
 120
 121        flush_cache_all();
 122
 123        s3c_pm_check_store();
 124
 125        /* send the cpu to sleep... */
 126
 127        s3c_pm_arch_stop_clocks();
 128
 129        /* this will also act as our return point from when
 130         * we resume as it saves its own register state and restores it
 131         * during the resume.  */
 132
 133        ret = cpu_suspend(0, pm_cpu_sleep);
 134        if (ret)
 135                return ret;
 136
 137        /* restore the system state */
 138
 139        s3c_pm_restore_core();
 140        s3c_pm_restore_uarts(soc_is_s3c2410());
 141
 142        if (!of_have_populated_dt()) {
 143                samsung_pm_restore_gpios();
 144                s3c_pm_restored_gpios();
 145        }
 146
 147        s3c_pm_debug_init_uart();
 148
 149        /* check what irq (if any) restored the system */
 150
 151        s3c_pm_arch_show_resume_irqs();
 152
 153        S3C_PMDBG("%s: post sleep, preparing to return\n", __func__);
 154
 155        /* LEDs should now be 1110 */
 156        s3c_pm_debug_smdkled(1 << 1, 0);
 157
 158        s3c_pm_check_restore();
 159
 160        /* ok, let's return from sleep */
 161
 162        S3C_PMDBG("S3C PM Resume (post-restore)\n");
 163        return 0;
 164}
 165
 166static int s3c_pm_prepare(void)
 167{
 168        /* prepare check area if configured */
 169
 170        s3c_pm_check_prepare();
 171        return 0;
 172}
 173
 174static void s3c_pm_finish(void)
 175{
 176        s3c_pm_check_cleanup();
 177}
 178
 179static const struct platform_suspend_ops s3c_pm_ops = {
 180        .enter          = s3c_pm_enter,
 181        .prepare        = s3c_pm_prepare,
 182        .finish         = s3c_pm_finish,
 183        .valid          = suspend_valid_only_mem,
 184};
 185
 186/* s3c_pm_init
 187 *
 188 * Attach the power management functions. This should be called
 189 * from the board specific initialisation if the board supports
 190 * it.
 191*/
 192
 193int __init s3c_pm_init(void)
 194{
 195        printk("S3C Power Management, Copyright 2004 Simtec Electronics\n");
 196
 197        suspend_set_ops(&s3c_pm_ops);
 198        return 0;
 199}
 200