xref: /linux/arch/sh/kernel/idle.c (revision c546656f31c5138afcaddfcd8f8b93fbf73e4d3a)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * The idle loop for all SuperH platforms.
4  *
5  *  Copyright (C) 2002 - 2009  Paul Mundt
6  */
7 #include <linux/cpu.h>
8 #include <linux/module.h>
9 #include <linux/init.h>
10 #include <linux/mm.h>
11 #include <linux/pm.h>
12 #include <linux/tick.h>
13 #include <linux/preempt.h>
14 #include <linux/thread_info.h>
15 #include <linux/irqflags.h>
16 #include <linux/smp.h>
17 #include <linux/atomic.h>
18 #include <asm/smp.h>
19 #include <asm/bl_bit.h>
20 
21 static void (*sh_idle)(void);
22 
23 void default_idle(void)
24 {
25 	set_bl_bit();
26 	raw_local_irq_enable();
27 	/* Isn't this racy ? */
28 	cpu_sleep();
29 	raw_local_irq_disable();
30 	clear_bl_bit();
31 }
32 
33 void __noreturn arch_cpu_idle_dead(void)
34 {
35 	play_dead();
36 }
37 
38 void arch_cpu_idle(void)
39 {
40 	sh_idle();
41 }
42 
43 void __init select_idle_routine(void)
44 {
45 	/*
46 	 * If a platform has set its own idle routine, leave it alone.
47 	 */
48 	if (!sh_idle)
49 		sh_idle = default_idle;
50 }
51 
52 void stop_this_cpu(void *unused)
53 {
54 	local_irq_disable();
55 	set_cpu_online(smp_processor_id(), false);
56 
57 	for (;;)
58 		cpu_sleep();
59 }
60