arch/mips/cobalt/reset.c

   1 /*
   2  * Cobalt Reset operations
   3  *
   4  * This file is subject to the terms and conditions of the GNU General Public
   5  * License.  See the file "COPYING" in the main directory of this archive
   6  * for more details.
   7  *
   8  * Copyright (C) 1995, 1996, 1997 by Ralf Baechle
   9  * Copyright (C) 2001 by Liam Davies (ldavies@agile.tv)
  10  */
  11 #include <linux/init.h>
  12 #include <linux/io.h>
  13 #include <linux/jiffies.h>
  14 #include <linux/leds.h>
  15
  16 #include <cobalt.h>
  17
  18 #define RESET_PORT      ((void __iomem *)CKSEG1ADDR(0x1c000000))
  19 #define RESET           0x0f
  20
  21 DEFINE_LED_TRIGGER(power_off_led_trigger);
  22
  23 static int __init ledtrig_power_off_init(void)
  24 {
  25         led_trigger_register_simple("power-off", &power_off_led_trigger);
  26         return 0;
  27 }
  28 device_initcall(ledtrig_power_off_init);
  29
  30 void cobalt_machine_halt(void)
  31 {
  32         int state, last, diff;
  33         unsigned long mark;
  34
  35         /*
  36          * turn on power off LED on RaQ
  37          *
  38          * restart if ENTER and SELECT are pressed
  39          */
  40
  41         last = COBALT_KEY_PORT;
  42
  43         led_trigger_event(power_off_led_trigger, LED_FULL);
  44
  45         for (state = 0;;) {
  46                 diff = COBALT_KEY_PORT ^ last;
  47                 last ^= diff;
  48
  49                 if((diff & (COBALT_KEY_ENTER | COBALT_KEY_SELECT)) && !(~last & (COBALT_KEY_ENTER | COBALT_KEY_SELECT)))
  50                         writeb(RESET, RESET_PORT);
  51
  52                 for (mark = jiffies; jiffies - mark < HZ;)
  53                         ;
  54         }
  55 }
  56
  57 void cobalt_machine_restart(char *command)
  58 {
  59         writeb(RESET, RESET_PORT);
  60
  61         /* we should never get here */
  62         cobalt_machine_halt();
  63 }