arch/sh/kernel/idle.c

   1 /*
   2  * The idle loop for all SuperH platforms.
   3  *
   4  *  Copyright (C) 2002 - 2009  Paul Mundt
   5  *
   6  * This file is subject to the terms and conditions of the GNU General Public
   7  * License.  See the file "COPYING" in the main directory of this archive
   8  * for more details.
   9  */
  10 #include <linux/module.h>
  11 #include <linux/init.h>
  12 #include <linux/mm.h>
  13 #include <linux/pm.h>
  14 #include <linux/tick.h>
  15 #include <linux/preempt.h>
  16 #include <linux/thread_info.h>
  17 #include <linux/irqflags.h>
  18 #include <linux/smp.h>
  19 #include <linux/atomic.h>
  20 #include <asm/pgalloc.h>
  21 #include <asm/smp.h>
  22 #include <asm/bl_bit.h>
  23
  24 static void (*sh_idle)(void);
  25
  26 void default_idle(void)
  27 {
  28         set_bl_bit();
  29         local_irq_enable();
  30         /* Isn't this racy ? */
  31         cpu_sleep();
  32         clear_bl_bit();
  33 }
  34
  35 void arch_cpu_idle_dead(void)
  36 {
  37         play_dead();
  38 }
  39
  40 void arch_cpu_idle(void)
  41 {
  42         sh_idle();
  43 }
  44
  45 void __init select_idle_routine(void)
  46 {
  47         /*
  48          * If a platform has set its own idle routine, leave it alone.
  49          */
  50         if (!sh_idle)
  51                 sh_idle = default_idle;
  52 }
  53
  54 void stop_this_cpu(void *unused)
  55 {
  56         local_irq_disable();
  57         set_cpu_online(smp_processor_id(), false);
  58
  59         for (;;)
  60                 cpu_sleep();
  61 }