/* *  arch/sh/kernel/time.c * *  Copyright (C) 1999  Tetsuya Okada & Niibe Yutaka *  Copyright (C) 2000  Philipp Rumpf <prumpf@tux.org> *  Copyright (C) 2002 - 2006  Paul Mundt *  Copyright (C) 2002  M. R. Brown  <mrbrown@linux-sh.org> * *  Some code taken from i386 version. *    Copyright (C) 1991, 1992, 1995  Linus Torvalds */#include <linux/kernel.h>#include <linux/module.h>#include <linux/init.h>#include <linux/profile.h>#include <linux/timex.h>#include <linux/sched.h>#include <asm/clock.h>#include <asm/rtc.h>#include <asm/timer.h>#include <asm/kgdb.h> struct sys_timer *sys_timer; /* Move this somewhere more sensible.. */DEFINE_SPINLOCK(rtc_lock);EXPORT_SYMBOL(rtc_lock); /* Dummy RTC ops */static void null_rtc_get_time(struct timespec *tv){	tv->tv_sec = mktime(2000, 1, 1, 0, 0, 0);	tv->tv_nsec = 0;} static int null_rtc_set_time(const time_t secs){	return 0;} void (*rtc_sh_get_time)(struct timespec *) = null_rtc_get_time;int (*rtc_sh_set_time)(const time_t) = null_rtc_set_time; #ifndef CONFIG_GENERIC_TIMEvoid do_gettimeofday(struct timeval *tv){	unsigned long flags;	unsigned long seq;	unsigned long usec, sec; 	do {		/*		 * Turn off IRQs when grabbing xtime_lock, so that		 * the sys_timer get_offset code doesn't have to handle it.		 */		seq = read_seqbegin_irqsave(&xtime_lock, flags);		usec = get_timer_offset();		sec = xtime.tv_sec;		usec += xtime.tv_nsec / NSEC_PER_USEC;	} while (read_seqretry_irqrestore(&xtime_lock, seq, flags)); 	while (usec >= 1000000) {		usec -= 1000000;		sec++;	} 	tv->tv_sec = sec;	tv->tv_usec = usec;}EXPORT_SYMBOL(do_gettimeofday); int do_settimeofday(struct timespec *tv){	time_t wtm_sec, sec = tv->tv_sec;	long wtm_nsec, nsec = tv->tv_nsec; 	if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC)		return -EINVAL; 	write_seqlock_irq(&xtime_lock);	/*	 * This is revolting. We need to set "xtime" correctly. However, the	 * value in this location is the value at the most recent update of	 * wall time.  Discover what correction gettimeofday() would have	 * made, and then undo it!	 */	nsec -= get_timer_offset() * NSEC_PER_USEC; 	wtm_sec  = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec);	wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec); 	set_normalized_timespec(&xtime, sec, nsec);	set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec); 	ntp_clear();	write_sequnlock_irq(&xtime_lock);	clock_was_set(); 	return 0;}EXPORT_SYMBOL(do_settimeofday);#endif /* !CONFIG_GENERIC_TIME */ /* last time the RTC clock got updated */static long last_rtc_update; /* * handle_timer_tick() needs to keep up the real-time clock, * as well as call the "do_timer()" routine every clocktick */void handle_timer_tick(void){	do_timer(1);#ifndef CONFIG_SMP	update_process_times(user_mode(get_irq_regs()));#endif	if (current->pid)		profile_tick(CPU_PROFILING); #ifdef CONFIG_HEARTBEAT	if (sh_mv.mv_heartbeat != NULL)		sh_mv.mv_heartbeat();#endif 	/*	 * If we have an externally synchronized Linux clock, then update	 * RTC clock accordingly every ~11 minutes. Set_rtc_mmss() has to be	 * called as close as possible to 500 ms before the new second starts.	 */	if (ntp_synced() &&	    xtime.tv_sec > last_rtc_update + 660 &&	    (xtime.tv_nsec / 1000) >= 500000 - ((unsigned) TICK_SIZE) / 2 &&	    (xtime.tv_nsec / 1000) <= 500000 + ((unsigned) TICK_SIZE) / 2) {		if (rtc_sh_set_time(xtime.tv_sec) == 0)			last_rtc_update = xtime.tv_sec;		else			/* do it again in 60s */			last_rtc_update = xtime.tv_sec - 600;	}} #ifdef CONFIG_PMint timer_suspend(struct sys_device *dev, pm_message_t state){	struct sys_timer *sys_timer = container_of(dev, struct sys_timer, dev); 	sys_timer->ops->stop(); 	return 0;} int timer_resume(struct sys_device *dev){	struct sys_timer *sys_timer = container_of(dev, struct sys_timer, dev); 	sys_timer->ops->start(); 	return 0;}#else#define timer_suspend NULL#define timer_resume NULL#endif static struct sysdev_class timer_sysclass = {	set_kset_name("timer"),	.suspend = timer_suspend,	.resume	 = timer_resume,}; #ifdef CONFIG_NO_IDLE_HZstatic int timer_dyn_tick_enable(void){	struct dyn_tick_timer *dyn_tick = sys_timer->dyn_tick;	unsigned long flags;	int ret = -ENODEV; 	if (dyn_tick) {		spin_lock_irqsave(&dyn_tick->lock, flags);		ret = 0;		if (!(dyn_tick->state & DYN_TICK_ENABLED)) {			ret = dyn_tick->enable(); 			if (ret == 0)				dyn_tick->state |= DYN_TICK_ENABLED;		}		spin_unlock_irqrestore(&dyn_tick->lock, flags);	} 	return ret;} static int timer_dyn_tick_disable(void){	struct dyn_tick_timer *dyn_tick = sys_timer->dyn_tick;	unsigned long flags;	int ret = -ENODEV; 	if (dyn_tick) {		spin_lock_irqsave(&dyn_tick->lock, flags);		ret = 0;		if (dyn_tick->state & DYN_TICK_ENABLED) {			ret = dyn_tick->disable(); 			if (ret == 0)				dyn_tick->state &= ~DYN_TICK_ENABLED;		}		spin_unlock_irqrestore(&dyn_tick->lock, flags);	} 	return ret;} /* * Reprogram the system timer for at least the calculated time interval. * This function should be called from the idle thread with IRQs disabled, * immediately before sleeping. */void timer_dyn_reprogram(void){	struct dyn_tick_timer *dyn_tick = sys_timer->dyn_tick;	unsigned long next, seq, flags; 	if (!dyn_tick)		return; 	spin_lock_irqsave(&dyn_tick->lock, flags);	if (dyn_tick->state & DYN_TICK_ENABLED) {		next = next_timer_interrupt();		do {			seq = read_seqbegin(&xtime_lock);			dyn_tick->reprogram(next - jiffies);		} while (read_seqretry(&xtime_lock, seq));	}	spin_unlock_irqrestore(&dyn_tick->lock, flags);} static ssize_t timer_show_dyn_tick(struct sys_device *dev, char *buf){	return sprintf(buf, "%i\n",		       (sys_timer->dyn_tick->state & DYN_TICK_ENABLED) >> 1);} static ssize_t timer_set_dyn_tick(struct sys_device *dev, const char *buf,				  size_t count){	unsigned int enable = simple_strtoul(buf, NULL, 2); 	if (enable)		timer_dyn_tick_enable();	else		timer_dyn_tick_disable(); 	return count;}static SYSDEV_ATTR(dyn_tick, 0644, timer_show_dyn_tick, timer_set_dyn_tick); /* * dyntick=enable|disable */static char dyntick_str[4] __initdata = ""; static int __init dyntick_setup(char *str){	if (str)		strlcpy(dyntick_str, str, sizeof(dyntick_str));	return 1;} __setup("dyntick=", dyntick_setup);#endif static int __init timer_init_sysfs(void){	int ret = sysdev_class_register(&timer_sysclass);	if (ret != 0)		return ret; 	sys_timer->dev.cls = &timer_sysclass;	ret = sysdev_register(&sys_timer->dev); #ifdef CONFIG_NO_IDLE_HZ	if (ret == 0 && sys_timer->dyn_tick) {		ret = sysdev_create_file(&sys_timer->dev, &attr_dyn_tick); 		/*		 * Turn on dynamic tick after calibrate delay		 * for correct bogomips		 */		if (ret == 0 && dyntick_str[0] == 'e')			ret = timer_dyn_tick_enable();	}#endif 	return ret;}device_initcall(timer_init_sysfs); void (*board_time_init)(void); void __init time_init(void){	if (board_time_init)		board_time_init(); 	clk_init(); 	rtc_sh_get_time(&xtime);	set_normalized_timespec(&wall_to_monotonic,				-xtime.tv_sec, -xtime.tv_nsec); 	/*	 * Find the timer to use as the system timer, it will be	 * initialized for us.	 */	sys_timer = get_sys_timer();	printk(KERN_INFO "Using %s for system timer\n", sys_timer->name); #ifdef CONFIG_NO_IDLE_HZ	if (sys_timer->dyn_tick)		spin_lock_init(&sys_timer->dyn_tick->lock);#endif #if defined(CONFIG_SH_KGDB)	/*	 * Set up kgdb as requested. We do it here because the serial	 * init uses the timer vars we just set up for figuring baud.	 */	kgdb_init();#endif}