xref: /linux/arch/sh/kernel/idle.c (revision 4b132aacb0768ac1e652cf517097ea6f237214b9)
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/processor.h>
19 #include <asm/smp.h>
20 #include <asm/bl_bit.h>
21 
22 static void (*sh_idle)(void);
23 
24 void default_idle(void)
25 {
26 	set_bl_bit();
27 	raw_local_irq_enable();
28 	/* Isn't this racy ? */
29 	cpu_sleep();
30 	raw_local_irq_disable();
31 	clear_bl_bit();
32 }
33 
34 void __noreturn arch_cpu_idle_dead(void)
35 {
36 	play_dead();
37 }
38 
39 void arch_cpu_idle(void)
40 {
41 	sh_idle();
42 }
43 
44 void __init select_idle_routine(void)
45 {
46 	/*
47 	 * If a platform has set its own idle routine, leave it alone.
48 	 */
49 	if (!sh_idle)
50 		sh_idle = default_idle;
51 }
52 
53 void stop_this_cpu(void *unused)
54 {
55 	local_irq_disable();
56 	set_cpu_online(smp_processor_id(), false);
57 
58 	for (;;)
59 		cpu_sleep();
60 }
61