arch/m68k/atari/time.c - linux - Git at Google

 /*
  * linux/arch/m68k/atari/time.c
  *
  * Atari time and real time clock stuff
  *
  * Assembled of parts of former atari/config.c 97-12-18 by Roman Hodek
  *
  * This file is subject to the terms and conditions of the GNU General Public
  * License.  See the file COPYING in the main directory of this archive
  * for more details.
  */

 #include <linux/types.h>
 #include <linux/mc146818rtc.h>
 #include <linux/interrupt.h>
 #include <linux/init.h>
 #include <linux/rtc.h>
 #include <linux/bcd.h>
 #include <linux/clocksource.h>
 #include <linux/delay.h>
 #include <linux/export.h>

 #include <asm/atariints.h>
 #include <asm/machdep.h>

 DEFINE_SPINLOCK(rtc_lock);
 EXPORT_SYMBOL_GPL(rtc_lock);

 static u64 atari_read_clk(struct clocksource *cs);

 static struct clocksource atari_clk = {
 	.name   = "mfp",
 	.rating = 100,
 	.read   = atari_read_clk,
 	.mask   = CLOCKSOURCE_MASK(32),
 	.flags  = CLOCK_SOURCE_IS_CONTINUOUS,
 };

 static u32 clk_total;
 static u8 last_timer_count;

 static irqreturn_t mfp_timer_c_handler(int irq, void *dev_id)
 {
 	unsigned long flags;

 	local_irq_save(flags);
 	do {
 		last_timer_count = st_mfp.tim_dt_c;
 	} while (last_timer_count == 1);
 	clk_total += INT_TICKS;
 	legacy_timer_tick(1);
 	timer_heartbeat();
 	local_irq_restore(flags);

 	return IRQ_HANDLED;
 }

 void __init
 atari_sched_init(void)
 {
     /* set Timer C data Register */
     st_mfp.tim_dt_c = INT_TICKS;
     /* start timer C, div = 1:100 */
     st_mfp.tim_ct_cd = (st_mfp.tim_ct_cd & 15) | 0x60;
     /* install interrupt service routine for MFP Timer C */
     if (request_irq(IRQ_MFP_TIMC, mfp_timer_c_handler, IRQF_TIMER, "timer",
                     NULL))
 	pr_err("Couldn't register timer interrupt\n");

     clocksource_register_hz(&atari_clk, INT_CLK);
 }

 /* ++andreas: gettimeoffset fixed to check for pending interrupt */

 static u64 atari_read_clk(struct clocksource *cs)
 {
 	unsigned long flags;
 	u8 count;
 	u32 ticks;

 	local_irq_save(flags);
 	/* Ensure that the count is monotonically decreasing, even though
 	 * the result may briefly stop changing after counter wrap-around.
 	 */
 	count = min(st_mfp.tim_dt_c, last_timer_count);
 	last_timer_count = count;

 	ticks = INT_TICKS - count;
 	ticks += clk_total;
 	local_irq_restore(flags);

 	return ticks;
 }


 static void mste_read(struct MSTE_RTC *val)
 {
 #define COPY(v) val->v=(mste_rtc.v & 0xf)
 	do {
 		COPY(sec_ones) ; COPY(sec_tens) ; COPY(min_ones) ;
 		COPY(min_tens) ; COPY(hr_ones) ; COPY(hr_tens) ;
 		COPY(weekday) ; COPY(day_ones) ; COPY(day_tens) ;
 		COPY(mon_ones) ; COPY(mon_tens) ; COPY(year_ones) ;
 		COPY(year_tens) ;
 	/* prevent from reading the clock while it changed */
 	} while (val->sec_ones != (mste_rtc.sec_ones & 0xf));
 #undef COPY
 }

 static void mste_write(struct MSTE_RTC *val)
 {
 #define COPY(v) mste_rtc.v=val->v
 	do {
 		COPY(sec_ones) ; COPY(sec_tens) ; COPY(min_ones) ;
 		COPY(min_tens) ; COPY(hr_ones) ; COPY(hr_tens) ;
 		COPY(weekday) ; COPY(day_ones) ; COPY(day_tens) ;
 		COPY(mon_ones) ; COPY(mon_tens) ; COPY(year_ones) ;
 		COPY(year_tens) ;
 	/* prevent from writing the clock while it changed */
 	} while (val->sec_ones != (mste_rtc.sec_ones & 0xf));
 #undef COPY
 }

 #define	RTC_READ(reg)				\
     ({	unsigned char	__val;			\
 		(void) atari_writeb(reg,&tt_rtc.regsel);	\
 		__val = tt_rtc.data;		\
 		__val;				\
 	})

 #define	RTC_WRITE(reg,val)			\
     do {					\
 		atari_writeb(reg,&tt_rtc.regsel);	\
 		tt_rtc.data = (val);		\
 	} while(0)


 #define HWCLK_POLL_INTERVAL	5

 int atari_mste_hwclk( int op, struct rtc_time *t )
 {
     int hour, year;
     int hr24=0;
     struct MSTE_RTC val;

     mste_rtc.mode=(mste_rtc.mode | 1);
     hr24=mste_rtc.mon_tens & 1;
     mste_rtc.mode=(mste_rtc.mode & ~1);

     if (op) {
         /* write: prepare values */

         val.sec_ones = t->tm_sec % 10;
         val.sec_tens = t->tm_sec / 10;
         val.min_ones = t->tm_min % 10;
         val.min_tens = t->tm_min / 10;
         hour = t->tm_hour;
         if (!hr24) {
 	    if (hour > 11)
 		hour += 20 - 12;
 	    if (hour == 0 || hour == 20)
 		hour += 12;
         }
         val.hr_ones = hour % 10;
         val.hr_tens = hour / 10;
         val.day_ones = t->tm_mday % 10;
         val.day_tens = t->tm_mday / 10;
         val.mon_ones = (t->tm_mon+1) % 10;
         val.mon_tens = (t->tm_mon+1) / 10;
         year = t->tm_year - 80;
         val.year_ones = year % 10;
         val.year_tens = year / 10;
         val.weekday = t->tm_wday;
         mste_write(&val);
         mste_rtc.mode=(mste_rtc.mode | 1);
         val.year_ones = (year % 4);	/* leap year register */
         mste_rtc.mode=(mste_rtc.mode & ~1);
     }
     else {
         mste_read(&val);
         t->tm_sec = val.sec_ones + val.sec_tens * 10;
         t->tm_min = val.min_ones + val.min_tens * 10;
         hour = val.hr_ones + val.hr_tens * 10;
 	if (!hr24) {
 	    if (hour == 12 || hour == 12 + 20)
 		hour -= 12;
 	    if (hour >= 20)
                 hour += 12 - 20;
         }
 	t->tm_hour = hour;
 	t->tm_mday = val.day_ones + val.day_tens * 10;
         t->tm_mon  = val.mon_ones + val.mon_tens * 10 - 1;
         t->tm_year = val.year_ones + val.year_tens * 10 + 80;
         t->tm_wday = val.weekday;
     }
     return 0;
 }

 int atari_tt_hwclk( int op, struct rtc_time *t )
 {
     int sec=0, min=0, hour=0, day=0, mon=0, year=0, wday=0;
     unsigned long	flags;
     unsigned char	ctrl;
     int pm = 0;

     ctrl = RTC_READ(RTC_CONTROL); /* control registers are
                                    * independent from the UIP */

     if (op) {
         /* write: prepare values */

         sec  = t->tm_sec;
         min  = t->tm_min;
         hour = t->tm_hour;
         day  = t->tm_mday;
         mon  = t->tm_mon + 1;
         year = t->tm_year - atari_rtc_year_offset;
         wday = t->tm_wday + (t->tm_wday >= 0);

         if (!(ctrl & RTC_24H)) {
 	    if (hour > 11) {
 		pm = 0x80;
 		if (hour != 12)
 		    hour -= 12;
 	    }
 	    else if (hour == 0)
 		hour = 12;
         }

         if (!(ctrl & RTC_DM_BINARY)) {
 	    sec = bin2bcd(sec);
 	    min = bin2bcd(min);
 	    hour = bin2bcd(hour);
 	    day = bin2bcd(day);
 	    mon = bin2bcd(mon);
 	    year = bin2bcd(year);
 	    if (wday >= 0)
 		wday = bin2bcd(wday);
         }
     }

     /* Reading/writing the clock registers is a bit critical due to
      * the regular update cycle of the RTC. While an update is in
      * progress, registers 0..9 shouldn't be touched.
      * The problem is solved like that: If an update is currently in
      * progress (the UIP bit is set), the process sleeps for a while
      * (50ms). This really should be enough, since the update cycle
      * normally needs 2 ms.
      * If the UIP bit reads as 0, we have at least 244 usecs until the
      * update starts. This should be enough... But to be sure,
      * additionally the RTC_SET bit is set to prevent an update cycle.
      */

     while( RTC_READ(RTC_FREQ_SELECT) & RTC_UIP ) {
 	if (in_atomic() || irqs_disabled())
 	    mdelay(1);
 	else
 	    schedule_timeout_interruptible(HWCLK_POLL_INTERVAL);
     }

     local_irq_save(flags);
     RTC_WRITE( RTC_CONTROL, ctrl | RTC_SET );
     if (!op) {
         sec  = RTC_READ( RTC_SECONDS );
         min  = RTC_READ( RTC_MINUTES );
         hour = RTC_READ( RTC_HOURS );
         day  = RTC_READ( RTC_DAY_OF_MONTH );
         mon  = RTC_READ( RTC_MONTH );
         year = RTC_READ( RTC_YEAR );
         wday = RTC_READ( RTC_DAY_OF_WEEK );
     }
     else {
         RTC_WRITE( RTC_SECONDS, sec );
         RTC_WRITE( RTC_MINUTES, min );
         RTC_WRITE( RTC_HOURS, hour + pm);
         RTC_WRITE( RTC_DAY_OF_MONTH, day );
         RTC_WRITE( RTC_MONTH, mon );
         RTC_WRITE( RTC_YEAR, year );
         if (wday >= 0) RTC_WRITE( RTC_DAY_OF_WEEK, wday );
     }
     RTC_WRITE( RTC_CONTROL, ctrl & ~RTC_SET );
     local_irq_restore(flags);

     if (!op) {
         /* read: adjust values */

         if (hour & 0x80) {
 	    hour &= ~0x80;
 	    pm = 1;
 	}

 	if (!(ctrl & RTC_DM_BINARY)) {
 	    sec = bcd2bin(sec);
 	    min = bcd2bin(min);
 	    hour = bcd2bin(hour);
 	    day = bcd2bin(day);
 	    mon = bcd2bin(mon);
 	    year = bcd2bin(year);
 	    wday = bcd2bin(wday);
         }

         if (!(ctrl & RTC_24H)) {
 	    if (!pm && hour == 12)
 		hour = 0;
 	    else if (pm && hour != 12)
 		hour += 12;
         }

         t->tm_sec  = sec;
         t->tm_min  = min;
         t->tm_hour = hour;
         t->tm_mday = day;
         t->tm_mon  = mon - 1;
         t->tm_year = year + atari_rtc_year_offset;
         t->tm_wday = wday - 1;
     }

     return( 0 );
 }
	/*
	* linux/arch/m68k/atari/time.c
	*
	* Atari time and real time clock stuff
	*
	* Assembled of parts of former atari/config.c 97-12-18 by Roman Hodek
	*
	* This file is subject to the terms and conditions of the GNU General Public
	* License. See the file COPYING in the main directory of this archive
	* for more details.
	*/

	#include <linux/types.h>
	#include <linux/mc146818rtc.h>
	#include <linux/interrupt.h>
	#include <linux/init.h>
	#include <linux/rtc.h>
	#include <linux/bcd.h>
	#include <linux/clocksource.h>
	#include <linux/delay.h>
	#include <linux/export.h>

	#include <asm/atariints.h>
	#include <asm/machdep.h>

	DEFINE_SPINLOCK(rtc_lock);
	EXPORT_SYMBOL_GPL(rtc_lock);

	static u64 atari_read_clk(struct clocksource *cs);

	static struct clocksource atari_clk = {
	.name = "mfp",
	.rating = 100,
	.read = atari_read_clk,
	.mask = CLOCKSOURCE_MASK(32),
	.flags = CLOCK_SOURCE_IS_CONTINUOUS,
	};

	static u32 clk_total;
	static u8 last_timer_count;

	static irqreturn_t mfp_timer_c_handler(int irq, void *dev_id)
	{
	unsigned long flags;

	local_irq_save(flags);
	do {
	last_timer_count = st_mfp.tim_dt_c;
	} while (last_timer_count == 1);
	clk_total += INT_TICKS;
	legacy_timer_tick(1);
	timer_heartbeat();
	local_irq_restore(flags);

	return IRQ_HANDLED;
	}

	void __init
	atari_sched_init(void)
	{
	/* set Timer C data Register */
	st_mfp.tim_dt_c = INT_TICKS;
	/* start timer C, div = 1:100 */
	st_mfp.tim_ct_cd = (st_mfp.tim_ct_cd & 15) \| 0x60;
	/* install interrupt service routine for MFP Timer C */
	if (request_irq(IRQ_MFP_TIMC, mfp_timer_c_handler, IRQF_TIMER, "timer",
	NULL))
	pr_err("Couldn't register timer interrupt\n");

	clocksource_register_hz(&atari_clk, INT_CLK);
	}

	/* ++andreas: gettimeoffset fixed to check for pending interrupt */

	static u64 atari_read_clk(struct clocksource *cs)
	{
	unsigned long flags;
	u8 count;
	u32 ticks;

	local_irq_save(flags);
	/* Ensure that the count is monotonically decreasing, even though
	* the result may briefly stop changing after counter wrap-around.
	*/
	count = min(st_mfp.tim_dt_c, last_timer_count);
	last_timer_count = count;

	ticks = INT_TICKS - count;
	ticks += clk_total;
	local_irq_restore(flags);

	return ticks;
	}


	static void mste_read(struct MSTE_RTC *val)
	{
	#define COPY(v) val->v=(mste_rtc.v & 0xf)
	do {
	COPY(sec_ones) ; COPY(sec_tens) ; COPY(min_ones) ;
	COPY(min_tens) ; COPY(hr_ones) ; COPY(hr_tens) ;
	COPY(weekday) ; COPY(day_ones) ; COPY(day_tens) ;
	COPY(mon_ones) ; COPY(mon_tens) ; COPY(year_ones) ;
	COPY(year_tens) ;
	/* prevent from reading the clock while it changed */
	} while (val->sec_ones != (mste_rtc.sec_ones & 0xf));
	#undef COPY
	}

	static void mste_write(struct MSTE_RTC *val)
	{
	#define COPY(v) mste_rtc.v=val->v
	do {
	COPY(sec_ones) ; COPY(sec_tens) ; COPY(min_ones) ;
	COPY(min_tens) ; COPY(hr_ones) ; COPY(hr_tens) ;
	COPY(weekday) ; COPY(day_ones) ; COPY(day_tens) ;
	COPY(mon_ones) ; COPY(mon_tens) ; COPY(year_ones) ;
	COPY(year_tens) ;
	/* prevent from writing the clock while it changed */
	} while (val->sec_ones != (mste_rtc.sec_ones & 0xf));
	#undef COPY
	}

	#define RTC_READ(reg) \
	({ unsigned char __val; \
	(void) atari_writeb(reg,&tt_rtc.regsel); \
	__val = tt_rtc.data; \
	__val; \
	})

	#define RTC_WRITE(reg,val) \
	do { \
	atari_writeb(reg,&tt_rtc.regsel); \
	tt_rtc.data = (val); \
	} while(0)


	#define HWCLK_POLL_INTERVAL 5

	int atari_mste_hwclk( int op, struct rtc_time *t )
	{
	int hour, year;
	int hr24=0;
	struct MSTE_RTC val;

	mste_rtc.mode=(mste_rtc.mode \| 1);
	hr24=mste_rtc.mon_tens & 1;
	mste_rtc.mode=(mste_rtc.mode & ~1);

	if (op) {
	/* write: prepare values */

	val.sec_ones = t->tm_sec % 10;
	val.sec_tens = t->tm_sec / 10;
	val.min_ones = t->tm_min % 10;
	val.min_tens = t->tm_min / 10;
	hour = t->tm_hour;
	if (!hr24) {
	if (hour > 11)
	hour += 20 - 12;
	if (hour == 0 \|\| hour == 20)
	hour += 12;
	}
	val.hr_ones = hour % 10;
	val.hr_tens = hour / 10;
	val.day_ones = t->tm_mday % 10;
	val.day_tens = t->tm_mday / 10;
	val.mon_ones = (t->tm_mon+1) % 10;
	val.mon_tens = (t->tm_mon+1) / 10;
	year = t->tm_year - 80;
	val.year_ones = year % 10;
	val.year_tens = year / 10;
	val.weekday = t->tm_wday;
	mste_write(&val);
	mste_rtc.mode=(mste_rtc.mode \| 1);
	val.year_ones = (year % 4); /* leap year register */
	mste_rtc.mode=(mste_rtc.mode & ~1);
	}
	else {
	mste_read(&val);
	t->tm_sec = val.sec_ones + val.sec_tens * 10;
	t->tm_min = val.min_ones + val.min_tens * 10;
	hour = val.hr_ones + val.hr_tens * 10;
	if (!hr24) {
	if (hour == 12 \|\| hour == 12 + 20)
	hour -= 12;
	if (hour >= 20)
	hour += 12 - 20;
	}
	t->tm_hour = hour;
	t->tm_mday = val.day_ones + val.day_tens * 10;
	t->tm_mon = val.mon_ones + val.mon_tens * 10 - 1;
	t->tm_year = val.year_ones + val.year_tens * 10 + 80;
	t->tm_wday = val.weekday;
	}
	return 0;
	}

	int atari_tt_hwclk( int op, struct rtc_time *t )
	{
	int sec=0, min=0, hour=0, day=0, mon=0, year=0, wday=0;
	unsigned long flags;
	unsigned char ctrl;
	int pm = 0;

	ctrl = RTC_READ(RTC_CONTROL); /* control registers are
	* independent from the UIP */

	if (op) {
	/* write: prepare values */

	sec = t->tm_sec;
	min = t->tm_min;
	hour = t->tm_hour;
	day = t->tm_mday;
	mon = t->tm_mon + 1;
	year = t->tm_year - atari_rtc_year_offset;
	wday = t->tm_wday + (t->tm_wday >= 0);

	if (!(ctrl & RTC_24H)) {
	if (hour > 11) {
	pm = 0x80;
	if (hour != 12)
	hour -= 12;
	}
	else if (hour == 0)
	hour = 12;
	}

	if (!(ctrl & RTC_DM_BINARY)) {
	sec = bin2bcd(sec);
	min = bin2bcd(min);
	hour = bin2bcd(hour);
	day = bin2bcd(day);
	mon = bin2bcd(mon);
	year = bin2bcd(year);
	if (wday >= 0)
	wday = bin2bcd(wday);
	}
	}

	/* Reading/writing the clock registers is a bit critical due to
	* the regular update cycle of the RTC. While an update is in
	* progress, registers 0..9 shouldn't be touched.
	* The problem is solved like that: If an update is currently in
	* progress (the UIP bit is set), the process sleeps for a while
	* (50ms). This really should be enough, since the update cycle
	* normally needs 2 ms.
	* If the UIP bit reads as 0, we have at least 244 usecs until the
	* update starts. This should be enough... But to be sure,
	* additionally the RTC_SET bit is set to prevent an update cycle.
	*/

	while( RTC_READ(RTC_FREQ_SELECT) & RTC_UIP ) {
	if (in_atomic() \|\| irqs_disabled())
	mdelay(1);
	else
	schedule_timeout_interruptible(HWCLK_POLL_INTERVAL);
	}

	local_irq_save(flags);
	RTC_WRITE( RTC_CONTROL, ctrl \| RTC_SET );
	if (!op) {
	sec = RTC_READ( RTC_SECONDS );
	min = RTC_READ( RTC_MINUTES );
	hour = RTC_READ( RTC_HOURS );
	day = RTC_READ( RTC_DAY_OF_MONTH );
	mon = RTC_READ( RTC_MONTH );
	year = RTC_READ( RTC_YEAR );
	wday = RTC_READ( RTC_DAY_OF_WEEK );
	}
	else {
	RTC_WRITE( RTC_SECONDS, sec );
	RTC_WRITE( RTC_MINUTES, min );
	RTC_WRITE( RTC_HOURS, hour + pm);
	RTC_WRITE( RTC_DAY_OF_MONTH, day );
	RTC_WRITE( RTC_MONTH, mon );
	RTC_WRITE( RTC_YEAR, year );
	if (wday >= 0) RTC_WRITE( RTC_DAY_OF_WEEK, wday );
	}
	RTC_WRITE( RTC_CONTROL, ctrl & ~RTC_SET );
	local_irq_restore(flags);

	if (!op) {
	/* read: adjust values */

	if (hour & 0x80) {
	hour &= ~0x80;
	pm = 1;
	}

	if (!(ctrl & RTC_DM_BINARY)) {
	sec = bcd2bin(sec);
	min = bcd2bin(min);
	hour = bcd2bin(hour);
	day = bcd2bin(day);
	mon = bcd2bin(mon);
	year = bcd2bin(year);
	wday = bcd2bin(wday);
	}

	if (!(ctrl & RTC_24H)) {
	if (!pm && hour == 12)
	hour = 0;
	else if (pm && hour != 12)
	hour += 12;
	}

	t->tm_sec = sec;
	t->tm_min = min;
	t->tm_hour = hour;
	t->tm_mday = day;
	t->tm_mon = mon - 1;
	t->tm_year = year + atari_rtc_year_offset;
	t->tm_wday = wday - 1;
	}

	return( 0 );
	}