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
  37 extern struct platform_device ip32_rtc_device;
  38
  39 static struct timer_list power_timer, blink_timer;
  40 static int has_panicked, shutting_down;
  41
  42 static __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
  65 static void ip32_machine_restart(char *cmd) __noreturn;
  66 static void ip32_machine_restart(char *cmd)
  67 {
  68         msleep(20);
  69         crime->control = CRIME_CONTROL_HARD_RESET;
  70         unreachable();
  71 }
  72
  73 static 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
  80 static void ip32_machine_halt(void)
  81 {
  82         ip32_poweroff(&ip32_rtc_device);
  83 }
  84
  85 static void power_timeout(unsigned long data)
  86 {
  87         ip32_poweroff(&ip32_rtc_device);
  88 }
  89
  90 void 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
 110 static 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
 129 static struct notifier_block panic_block = {
 130         .notifier_call = panic_event,
 131 };
 132
 133 static __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
 152 subsys_initcall(ip32_reboot_setup);