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/cpuidle.h>
  20 #include <linux/atomic.h>
  21 #include <asm/pgalloc.h>
  22 #include <asm/smp.h>
  23 #include <asm/bl_bit.h>
  24
  25 static void (*sh_idle)(void);
  26
  27 void default_idle(void)
  28 {
  29         set_bl_bit();
  30         local_irq_enable();
  31         /* Isn't this racy ? */
  32         cpu_sleep();
  33         clear_bl_bit();
  34 }
  35
  36 void arch_cpu_idle_dead(void)
  37 {
  38         play_dead();
  39 }
  40
  41 void arch_cpu_idle(void)
  42 {
  43         if (cpuidle_idle_call())
  44                 sh_idle();
  45 }
  46
  47 void __init select_idle_routine(void)
  48 {
  49         /*
  50          * If a platform has set its own idle routine, leave it alone.
  51          */
  52         if (!sh_idle)
  53                 sh_idle = default_idle;
  54 }
  55
  56 void stop_this_cpu(void *unused)
  57 {
  58         local_irq_disable();
  59         set_cpu_online(smp_processor_id(), false);
  60
  61         for (;;)
  62                 cpu_sleep();
  63 }