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/panic_notifier.h>
  16#include <linux/sched.h>
  17#include <linux/sched/signal.h>
  18#include <linux/notifier.h>
  19#include <linux/delay.h>
  20#include <linux/rtc/ds1685.h>
  21#include <linux/interrupt.h>
  22#include <linux/pm.h>
  23
  24#include <asm/addrspace.h>
  25#include <asm/irq.h>
  26#include <asm/reboot.h>
  27#include <asm/wbflush.h>
  28#include <asm/ip32/mace.h>
  29#include <asm/ip32/crime.h>
  30#include <asm/ip32/ip32_ints.h>
  31
  32#define POWERDOWN_TIMEOUT       120
  33/*
  34 * Blink frequency during reboot grace period and when panicked.
  35 */
  36#define POWERDOWN_FREQ          (HZ / 4)
  37#define PANIC_FREQ              (HZ / 8)
  38
  39extern struct platform_device ip32_rtc_device;
  40
  41static struct timer_list power_timer, blink_timer;
  42static unsigned long blink_timer_timeout;
  43static int has_panicked, shutting_down;
  44
  45static __noreturn void ip32_poweroff(void *data)
  46{
  47        void (*poweroff_func)(struct platform_device *) =
  48                symbol_get(ds1685_rtc_poweroff);
  49
  50#ifdef CONFIG_MODULES
  51        /* If the first __symbol_get failed, our module wasn't loaded. */
  52        if (!poweroff_func) {
  53                request_module("rtc-ds1685");
  54                poweroff_func = symbol_get(ds1685_rtc_poweroff);
  55        }
  56#endif
  57
  58        if (!poweroff_func)
  59                pr_emerg("RTC not available for power-off.  Spinning forever ...\n");
  60        else {
  61                (*poweroff_func)((struct platform_device *)data);
  62                symbol_put(ds1685_rtc_poweroff);
  63        }
  64
  65        unreachable();
  66}
  67
  68static void ip32_machine_restart(char *cmd) __noreturn;
  69static void ip32_machine_restart(char *cmd)
  70{
  71        msleep(20);
  72        crime->control = CRIME_CONTROL_HARD_RESET;
  73        unreachable();
  74}
  75
  76static void blink_timeout(struct timer_list *unused)
  77{
  78        unsigned long led = mace->perif.ctrl.misc ^ MACEISA_LED_RED;
  79        mace->perif.ctrl.misc = led;
  80        mod_timer(&blink_timer, jiffies + blink_timer_timeout);
  81}
  82
  83static void ip32_machine_halt(void)
  84{
  85        ip32_poweroff(&ip32_rtc_device);
  86}
  87
  88static void power_timeout(struct timer_list *unused)
  89{
  90        ip32_poweroff(&ip32_rtc_device);
  91}
  92
  93void ip32_prepare_poweroff(void)
  94{
  95        if (has_panicked)
  96                return;
  97
  98        if (shutting_down || kill_cad_pid(SIGINT, 1)) {
  99                /* No init process or button pressed twice.  */
 100                ip32_poweroff(&ip32_rtc_device);
 101        }
 102
 103        shutting_down = 1;
 104        blink_timer_timeout = POWERDOWN_FREQ;
 105        blink_timeout(&blink_timer);
 106
 107        timer_setup(&power_timer, power_timeout, 0);
 108        power_timer.expires = jiffies + POWERDOWN_TIMEOUT * HZ;
 109        add_timer(&power_timer);
 110}
 111
 112static int panic_event(struct notifier_block *this, unsigned long event,
 113                       void *ptr)
 114{
 115        unsigned long led;
 116
 117        if (has_panicked)
 118                return NOTIFY_DONE;
 119        has_panicked = 1;
 120
 121        /* turn off the green LED */
 122        led = mace->perif.ctrl.misc | MACEISA_LED_GREEN;
 123        mace->perif.ctrl.misc = led;
 124
 125        blink_timer_timeout = PANIC_FREQ;
 126        blink_timeout(&blink_timer);
 127
 128        return NOTIFY_DONE;
 129}
 130
 131static struct notifier_block panic_block = {
 132        .notifier_call = panic_event,
 133};
 134
 135static __init int ip32_reboot_setup(void)
 136{
 137        /* turn on the green led only */
 138        unsigned long led = mace->perif.ctrl.misc;
 139        led |= MACEISA_LED_RED;
 140        led &= ~MACEISA_LED_GREEN;
 141        mace->perif.ctrl.misc = led;
 142
 143        _machine_restart = ip32_machine_restart;
 144        _machine_halt = ip32_machine_halt;
 145        pm_power_off = ip32_machine_halt;
 146
 147        timer_setup(&blink_timer, blink_timeout, 0);
 148        atomic_notifier_chain_register(&panic_notifier_list, &panic_block);
 149
 150        return 0;
 151}
 152
 153subsys_initcall(ip32_reboot_setup);
 154