xref: /openbmc/linux/arch/sh/kernel/idle.c (revision 827634ad)
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 }
62