xref: /openbmc/linux/arch/sh/kernel/idle.c (revision 39b6f3aa)
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 }
64