/* $Id: time.c,v 1.18 2005/03/04 08:16:17 starvik Exp $ * *  linux/arch/cris/kernel/time.c * *  Copyright (C) 1991, 1992, 1995  Linus Torvalds *  Copyright (C) 1999, 2000, 2001 Axis Communications AB * * 1994-07-02    Alan Modra *	fixed set_rtc_mmss, fixed time.year for >= 2000, new mktime * 1995-03-26    Markus Kuhn *      fixed 500 ms bug at call to set_rtc_mmss, fixed DS12887 *      precision CMOS clock update * 1996-05-03    Ingo Molnar *      fixed time warps in do_[slow|fast]_gettimeoffset() * 1997-09-10	Updated NTP code according to technical memorandum Jan '96 *		"A Kernel Model for Precision Timekeeping" by Dave Mills * * Linux/CRIS specific code: * * Authors:    Bjorn Wesen *             Johan Adolfsson   * */ #include <asm/rtc.h>#include <linux/errno.h>#include <linux/module.h>#include <linux/param.h>#include <linux/jiffies.h>#include <linux/bcd.h>#include <linux/timex.h>#include <linux/init.h>#include <linux/profile.h>#include <linux/sched.h>	/* just for sched_clock() - funny that */ int have_rtc;  /* used to remember if we have an RTC or not */; #define TICK_SIZE tick extern unsigned long loops_per_jiffy; /* init/main.c */unsigned long loops_per_usec; extern unsigned long do_slow_gettimeoffset(void);static unsigned long (*do_gettimeoffset)(void) = do_slow_gettimeoffset; /* * This version of gettimeofday has near microsecond resolution. * * Note: Division is quite slow on CRIS and do_gettimeofday is called *       rather often. Maybe we should do some kind of approximation here *       (a naive approximation would be to divide by 1024). */void do_gettimeofday(struct timeval *tv){	unsigned long flags;	signed long usec, sec;	local_irq_save(flags);	usec = do_gettimeoffset();         /*	 * If time_adjust is negative then NTP is slowing the clock	 * so make sure not to go into next possible interval.	 * Better to lose some accuracy than have time go backwards..	 */	if (unlikely(time_adjust < 0) && usec > tickadj)		usec = tickadj; 	sec = xtime.tv_sec;	usec += xtime.tv_nsec / 1000;	local_irq_restore(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 -= do_gettimeoffset() * 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);  /* * BUG: This routine does not handle hour overflow properly; it just *      sets the minutes. Usually you'll only notice that after reboot! */ int set_rtc_mmss(unsigned long nowtime){	int retval = 0;	int real_seconds, real_minutes, cmos_minutes; 	printk(KERN_DEBUG "set_rtc_mmss(%lu)\n", nowtime); 	if(!have_rtc)		return 0; 	cmos_minutes = CMOS_READ(RTC_MINUTES);	BCD_TO_BIN(cmos_minutes); 	/*	 * since we're only adjusting minutes and seconds,	 * don't interfere with hour overflow. This avoids	 * messing with unknown time zones but requires your	 * RTC not to be off by more than 15 minutes	 */	real_seconds = nowtime % 60;	real_minutes = nowtime / 60;	if (((abs(real_minutes - cmos_minutes) + 15)/30) & 1)		real_minutes += 30;		/* correct for half hour time zone */	real_minutes %= 60; 	if (abs(real_minutes - cmos_minutes) < 30) {		BIN_TO_BCD(real_seconds);		BIN_TO_BCD(real_minutes);		CMOS_WRITE(real_seconds,RTC_SECONDS);		CMOS_WRITE(real_minutes,RTC_MINUTES);	} else {		printk(KERN_WARNING		       "set_rtc_mmss: can't update from %d to %d\n",		       cmos_minutes, real_minutes);		retval = -1;	} 	return retval;} /* grab the time from the RTC chip */ unsigned longget_cmos_time(void){	unsigned int year, mon, day, hour, min, sec; 	sec = CMOS_READ(RTC_SECONDS);	min = CMOS_READ(RTC_MINUTES);	hour = CMOS_READ(RTC_HOURS);	day = CMOS_READ(RTC_DAY_OF_MONTH);	mon = CMOS_READ(RTC_MONTH);	year = CMOS_READ(RTC_YEAR); 	printk(KERN_DEBUG	       "rtc: sec 0x%x min 0x%x hour 0x%x day 0x%x mon 0x%x year 0x%x\n",	       sec, min, hour, day, mon, year); 	BCD_TO_BIN(sec);	BCD_TO_BIN(min);	BCD_TO_BIN(hour);	BCD_TO_BIN(day);	BCD_TO_BIN(mon);	BCD_TO_BIN(year); 	if ((year += 1900) < 1970)		year += 100; 	return mktime(year, mon, day, hour, min, sec);} /* update xtime from the CMOS settings. used when /dev/rtc gets a SET_TIME. * TODO: this doesn't reset the fancy NTP phase stuff as do_settimeofday does. */ voidupdate_xtime_from_cmos(void){	if(have_rtc) {		xtime.tv_sec = get_cmos_time();		xtime.tv_nsec = 0;	}} extern void cris_profile_sample(struct pt_regs* regs); voidcris_do_profile(struct pt_regs* regs){ #if CONFIG_SYSTEM_PROFILER        cris_profile_sample(regs);#endif #if CONFIG_PROFILING        profile_tick(CPU_PROFILING, regs);#endif} static int__init init_udelay(void){	loops_per_usec = (loops_per_jiffy * HZ) / 1000000;	return 0;} __initcall(init_udelay);