82 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			82 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * The idle loop for all SuperH platforms.
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|  *
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|  *  Copyright (C) 2002 - 2008  Paul Mundt
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|  *
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|  * This file is subject to the terms and conditions of the GNU General Public
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|  * License.  See the file "COPYING" in the main directory of this archive
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|  * for more details.
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|  */
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| #include <linux/module.h>
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| #include <linux/init.h>
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| #include <linux/mm.h>
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| #include <linux/pm.h>
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| #include <linux/tick.h>
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| #include <linux/preempt.h>
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| #include <linux/thread_info.h>
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| #include <linux/irqflags.h>
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| #include <asm/pgalloc.h>
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| #include <asm/system.h>
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| #include <asm/atomic.h>
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| 
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| static int hlt_counter;
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| void (*pm_idle)(void);
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| void (*pm_power_off)(void);
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| EXPORT_SYMBOL(pm_power_off);
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| 
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| static int __init nohlt_setup(char *__unused)
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| {
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| 	hlt_counter = 1;
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| 	return 1;
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| }
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| __setup("nohlt", nohlt_setup);
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| 
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| static int __init hlt_setup(char *__unused)
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| {
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| 	hlt_counter = 0;
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| 	return 1;
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| }
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| __setup("hlt", hlt_setup);
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| 
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| static void default_idle(void)
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| {
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| 	if (!hlt_counter) {
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| 		clear_thread_flag(TIF_POLLING_NRFLAG);
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| 		smp_mb__after_clear_bit();
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| 		set_bl_bit();
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| 		stop_critical_timings();
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| 
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| 		while (!need_resched())
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| 			cpu_sleep();
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| 
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| 		start_critical_timings();
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| 		clear_bl_bit();
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| 		set_thread_flag(TIF_POLLING_NRFLAG);
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| 	} else
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| 		while (!need_resched())
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| 			cpu_relax();
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| }
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| 
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| void cpu_idle(void)
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| {
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| 	set_thread_flag(TIF_POLLING_NRFLAG);
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| 
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| 	/* endless idle loop with no priority at all */
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| 	while (1) {
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| 		void (*idle)(void) = pm_idle;
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| 
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| 		if (!idle)
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| 			idle = default_idle;
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| 
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| 		tick_nohz_stop_sched_tick(1);
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| 		while (!need_resched())
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| 			idle();
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| 		tick_nohz_restart_sched_tick();
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| 
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| 		preempt_enable_no_resched();
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| 		schedule();
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| 		preempt_disable();
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| 		check_pgt_cache();
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| 	}
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| }
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