LXR linux/arch/mips/sgi-ip32/ip32-reset.c

   1/*
   2 * This file is subject to the terms and conditions of the GNU General Public
   3 * License.  See the file "COPYING" in the main directory of this archive
   4 * for more details.
   5 *
   6 * Copyright (C) 2001 Keith M Wesolowski
   7 * Copyright (C) 2001 Paul Mundt
   8 * Copyright (C) 2003 Guido Guenther <agx@sigxcpu.org>
   9 */
  10
  11#include <linux/compiler.h>
  12#include <linux/init.h>
  13#include <linux/kernel.h>
  14#include <linux/module.h>
  15#include <linux/sched.h>
  16#include <linux/notifier.h>
  17#include <linux/delay.h>
  18#include <linux/rtc/ds1685.h>
  19#include <linux/interrupt.h>
  20#include <linux/pm.h>
  21
  22#include <asm/addrspace.h>
  23#include <asm/irq.h>
  24#include <asm/reboot.h>
  25#include <asm/wbflush.h>
  26#include <asm/ip32/mace.h>
  27#include <asm/ip32/crime.h>
  28#include <asm/ip32/ip32_ints.h>
  29
  30#define POWERDOWN_TIMEOUT       120
  31/*
  32 * Blink frequency during reboot grace period and when panicked.
  33 */
  34#define POWERDOWN_FREQ          (HZ / 4)
  35#define PANIC_FREQ              (HZ / 8)
  36
  37extern struct platform_device ip32_rtc_device;
  38
  39static struct timer_list power_timer, blink_timer;
  40static int has_panicked, shutting_down;
  41
  42static __noreturn void ip32_poweroff(void *data)
  43{
  44        void (*poweroff_func)(struct platform_device *) =
  45                symbol_get(ds1685_rtc_poweroff);
  46
  47#ifdef CONFIG_MODULES
  48        /* If the first __symbol_get failed, our module wasn't loaded. */
  49        if (!poweroff_func) {
  50                request_module("rtc-ds1685");
  51                poweroff_func = symbol_get(ds1685_rtc_poweroff);
  52        }
  53#endif
  54
  55        if (!poweroff_func)
  56                pr_emerg("RTC not available for power-off.  Spinning forever ...\n");
  57        else {
  58                (*poweroff_func)((struct platform_device *)data);
  59                symbol_put(ds1685_rtc_poweroff);
  60        }
  61
  62        unreachable();
  63}
  64
  65static void ip32_machine_restart(char *cmd) __noreturn;
  66static void ip32_machine_restart(char *cmd)
  67{
  68        msleep(20);
  69        crime->control = CRIME_CONTROL_HARD_RESET;
  70        unreachable();
  71}
  72
  73static void blink_timeout(unsigned long data)
  74{
  75        unsigned long led = mace->perif.ctrl.misc ^ MACEISA_LED_RED;
  76        mace->perif.ctrl.misc = led;
  77        mod_timer(&blink_timer, jiffies + data);
  78}
  79
  80static void ip32_machine_halt(void)
  81{
  82        ip32_poweroff(&ip32_rtc_device);
  83}
  84
  85static void power_timeout(unsigned long data)
  86{
  87        ip32_poweroff(&ip32_rtc_device);
  88}
  89
  90void ip32_prepare_poweroff(void)
  91{
  92        if (has_panicked)
  93                return;
  94
  95        if (shutting_down || kill_cad_pid(SIGINT, 1)) {
  96                /* No init process or button pressed twice.  */
  97                ip32_poweroff(&ip32_rtc_device);
  98        }
  99
 100        shutting_down = 1;
 101        blink_timer.data = POWERDOWN_FREQ;
 102        blink_timeout(POWERDOWN_FREQ);
 103
 104        init_timer(&power_timer);
 105        power_timer.function = power_timeout;
 106        power_timer.expires = jiffies + POWERDOWN_TIMEOUT * HZ;
 107        add_timer(&power_timer);
 108}
 109
 110static int panic_event(struct notifier_block *this, unsigned long event,
 111                       void *ptr)
 112{
 113        unsigned long led;
 114
 115        if (has_panicked)
 116                return NOTIFY_DONE;
 117        has_panicked = 1;
 118
 119        /* turn off the green LED */
 120        led = mace->perif.ctrl.misc | MACEISA_LED_GREEN;
 121        mace->perif.ctrl.misc = led;
 122
 123        blink_timer.data = PANIC_FREQ;
 124        blink_timeout(PANIC_FREQ);
 125
 126        return NOTIFY_DONE;
 127}
 128
 129static struct notifier_block panic_block = {
 130        .notifier_call = panic_event,
 131};
 132
 133static __init int ip32_reboot_setup(void)
 134{
 135        /* turn on the green led only */
 136        unsigned long led = mace->perif.ctrl.misc;
 137        led |= MACEISA_LED_RED;
 138        led &= ~MACEISA_LED_GREEN;
 139        mace->perif.ctrl.misc = led;
 140
 141        _machine_restart = ip32_machine_restart;
 142        _machine_halt = ip32_machine_halt;
 143        pm_power_off = ip32_machine_halt;
 144
 145        init_timer(&blink_timer);
 146        blink_timer.function = blink_timeout;
 147        atomic_notifier_chain_register(&panic_notifier_list, &panic_block);
 148
 149        return 0;
 150}
 151
 152subsys_initcall(ip32_reboot_setup);
 153