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v6.2
  1/*
  2 * linux/arch/m68k/atari/time.c
  3 *
  4 * Atari time and real time clock stuff
  5 *
  6 * Assembled of parts of former atari/config.c 97-12-18 by Roman Hodek
  7 *
  8 * This file is subject to the terms and conditions of the GNU General Public
  9 * License.  See the file COPYING in the main directory of this archive
 10 * for more details.
 11 */
 12
 13#include <linux/types.h>
 14#include <linux/mc146818rtc.h>
 15#include <linux/interrupt.h>
 16#include <linux/init.h>
 17#include <linux/rtc.h>
 18#include <linux/bcd.h>
 19#include <linux/clocksource.h>
 20#include <linux/delay.h>
 21#include <linux/export.h>
 22
 23#include <asm/atariints.h>
 24#include <asm/machdep.h>
 25
 
 
 26DEFINE_SPINLOCK(rtc_lock);
 27EXPORT_SYMBOL_GPL(rtc_lock);
 28
 29static u64 atari_read_clk(struct clocksource *cs);
 30
 31static struct clocksource atari_clk = {
 32	.name   = "mfp",
 33	.rating = 100,
 34	.read   = atari_read_clk,
 35	.mask   = CLOCKSOURCE_MASK(32),
 36	.flags  = CLOCK_SOURCE_IS_CONTINUOUS,
 37};
 38
 39static u32 clk_total;
 40static u8 last_timer_count;
 41
 42static irqreturn_t mfp_timer_c_handler(int irq, void *dev_id)
 43{
 44	unsigned long flags;
 45
 46	local_irq_save(flags);
 47	do {
 48		last_timer_count = st_mfp.tim_dt_c;
 49	} while (last_timer_count == 1);
 50	clk_total += INT_TICKS;
 51	legacy_timer_tick(1);
 52	timer_heartbeat();
 53	local_irq_restore(flags);
 54
 55	return IRQ_HANDLED;
 56}
 57
 58void __init
 59atari_sched_init(void)
 60{
 61    /* set Timer C data Register */
 62    st_mfp.tim_dt_c = INT_TICKS;
 63    /* start timer C, div = 1:100 */
 64    st_mfp.tim_ct_cd = (st_mfp.tim_ct_cd & 15) | 0x60;
 65    /* install interrupt service routine for MFP Timer C */
 66    if (request_irq(IRQ_MFP_TIMC, mfp_timer_c_handler, IRQF_TIMER, "timer",
 67                    NULL))
 68	pr_err("Couldn't register timer interrupt\n");
 69
 70    clocksource_register_hz(&atari_clk, INT_CLK);
 71}
 72
 73/* ++andreas: gettimeoffset fixed to check for pending interrupt */
 74
 75static u64 atari_read_clk(struct clocksource *cs)
 76{
 77	unsigned long flags;
 78	u8 count;
 79	u32 ticks;
 80
 81	local_irq_save(flags);
 82	/* Ensure that the count is monotonically decreasing, even though
 83	 * the result may briefly stop changing after counter wrap-around.
 84	 */
 85	count = min(st_mfp.tim_dt_c, last_timer_count);
 86	last_timer_count = count;
 87
 88	ticks = INT_TICKS - count;
 89	ticks += clk_total;
 90	local_irq_restore(flags);
 91
 92	return ticks;
 93}
 94
 95
 96static void mste_read(struct MSTE_RTC *val)
 97{
 98#define COPY(v) val->v=(mste_rtc.v & 0xf)
 99	do {
100		COPY(sec_ones) ; COPY(sec_tens) ; COPY(min_ones) ;
101		COPY(min_tens) ; COPY(hr_ones) ; COPY(hr_tens) ;
102		COPY(weekday) ; COPY(day_ones) ; COPY(day_tens) ;
103		COPY(mon_ones) ; COPY(mon_tens) ; COPY(year_ones) ;
104		COPY(year_tens) ;
105	/* prevent from reading the clock while it changed */
106	} while (val->sec_ones != (mste_rtc.sec_ones & 0xf));
107#undef COPY
108}
109
110static void mste_write(struct MSTE_RTC *val)
111{
112#define COPY(v) mste_rtc.v=val->v
113	do {
114		COPY(sec_ones) ; COPY(sec_tens) ; COPY(min_ones) ;
115		COPY(min_tens) ; COPY(hr_ones) ; COPY(hr_tens) ;
116		COPY(weekday) ; COPY(day_ones) ; COPY(day_tens) ;
117		COPY(mon_ones) ; COPY(mon_tens) ; COPY(year_ones) ;
118		COPY(year_tens) ;
119	/* prevent from writing the clock while it changed */
120	} while (val->sec_ones != (mste_rtc.sec_ones & 0xf));
121#undef COPY
122}
123
124#define	RTC_READ(reg)				\
125    ({	unsigned char	__val;			\
126		(void) atari_writeb(reg,&tt_rtc.regsel);	\
127		__val = tt_rtc.data;		\
128		__val;				\
129	})
130
131#define	RTC_WRITE(reg,val)			\
132    do {					\
133		atari_writeb(reg,&tt_rtc.regsel);	\
134		tt_rtc.data = (val);		\
135	} while(0)
136
137
138#define HWCLK_POLL_INTERVAL	5
139
140int atari_mste_hwclk( int op, struct rtc_time *t )
141{
142    int hour, year;
143    int hr24=0;
144    struct MSTE_RTC val;
145
146    mste_rtc.mode=(mste_rtc.mode | 1);
147    hr24=mste_rtc.mon_tens & 1;
148    mste_rtc.mode=(mste_rtc.mode & ~1);
149
150    if (op) {
151        /* write: prepare values */
152
153        val.sec_ones = t->tm_sec % 10;
154        val.sec_tens = t->tm_sec / 10;
155        val.min_ones = t->tm_min % 10;
156        val.min_tens = t->tm_min / 10;
157        hour = t->tm_hour;
158        if (!hr24) {
159	    if (hour > 11)
160		hour += 20 - 12;
161	    if (hour == 0 || hour == 20)
162		hour += 12;
163        }
164        val.hr_ones = hour % 10;
165        val.hr_tens = hour / 10;
166        val.day_ones = t->tm_mday % 10;
167        val.day_tens = t->tm_mday / 10;
168        val.mon_ones = (t->tm_mon+1) % 10;
169        val.mon_tens = (t->tm_mon+1) / 10;
170        year = t->tm_year - 80;
171        val.year_ones = year % 10;
172        val.year_tens = year / 10;
173        val.weekday = t->tm_wday;
174        mste_write(&val);
175        mste_rtc.mode=(mste_rtc.mode | 1);
176        val.year_ones = (year % 4);	/* leap year register */
177        mste_rtc.mode=(mste_rtc.mode & ~1);
178    }
179    else {
180        mste_read(&val);
181        t->tm_sec = val.sec_ones + val.sec_tens * 10;
182        t->tm_min = val.min_ones + val.min_tens * 10;
183        hour = val.hr_ones + val.hr_tens * 10;
184	if (!hr24) {
185	    if (hour == 12 || hour == 12 + 20)
186		hour -= 12;
187	    if (hour >= 20)
188                hour += 12 - 20;
189        }
190	t->tm_hour = hour;
191	t->tm_mday = val.day_ones + val.day_tens * 10;
192        t->tm_mon  = val.mon_ones + val.mon_tens * 10 - 1;
193        t->tm_year = val.year_ones + val.year_tens * 10 + 80;
194        t->tm_wday = val.weekday;
195    }
196    return 0;
197}
198
199int atari_tt_hwclk( int op, struct rtc_time *t )
200{
201    int sec=0, min=0, hour=0, day=0, mon=0, year=0, wday=0;
202    unsigned long	flags;
203    unsigned char	ctrl;
204    int pm = 0;
205
206    ctrl = RTC_READ(RTC_CONTROL); /* control registers are
207                                   * independent from the UIP */
208
209    if (op) {
210        /* write: prepare values */
211
212        sec  = t->tm_sec;
213        min  = t->tm_min;
214        hour = t->tm_hour;
215        day  = t->tm_mday;
216        mon  = t->tm_mon + 1;
217        year = t->tm_year - atari_rtc_year_offset;
218        wday = t->tm_wday + (t->tm_wday >= 0);
219
220        if (!(ctrl & RTC_24H)) {
221	    if (hour > 11) {
222		pm = 0x80;
223		if (hour != 12)
224		    hour -= 12;
225	    }
226	    else if (hour == 0)
227		hour = 12;
228        }
229
230        if (!(ctrl & RTC_DM_BINARY)) {
231	    sec = bin2bcd(sec);
232	    min = bin2bcd(min);
233	    hour = bin2bcd(hour);
234	    day = bin2bcd(day);
235	    mon = bin2bcd(mon);
236	    year = bin2bcd(year);
237	    if (wday >= 0)
238		wday = bin2bcd(wday);
239        }
240    }
241
242    /* Reading/writing the clock registers is a bit critical due to
243     * the regular update cycle of the RTC. While an update is in
244     * progress, registers 0..9 shouldn't be touched.
245     * The problem is solved like that: If an update is currently in
246     * progress (the UIP bit is set), the process sleeps for a while
247     * (50ms). This really should be enough, since the update cycle
248     * normally needs 2 ms.
249     * If the UIP bit reads as 0, we have at least 244 usecs until the
250     * update starts. This should be enough... But to be sure,
251     * additionally the RTC_SET bit is set to prevent an update cycle.
252     */
253
254    while( RTC_READ(RTC_FREQ_SELECT) & RTC_UIP ) {
255	if (in_atomic() || irqs_disabled())
256	    mdelay(1);
257	else
258	    schedule_timeout_interruptible(HWCLK_POLL_INTERVAL);
259    }
260
261    local_irq_save(flags);
262    RTC_WRITE( RTC_CONTROL, ctrl | RTC_SET );
263    if (!op) {
264        sec  = RTC_READ( RTC_SECONDS );
265        min  = RTC_READ( RTC_MINUTES );
266        hour = RTC_READ( RTC_HOURS );
267        day  = RTC_READ( RTC_DAY_OF_MONTH );
268        mon  = RTC_READ( RTC_MONTH );
269        year = RTC_READ( RTC_YEAR );
270        wday = RTC_READ( RTC_DAY_OF_WEEK );
271    }
272    else {
273        RTC_WRITE( RTC_SECONDS, sec );
274        RTC_WRITE( RTC_MINUTES, min );
275        RTC_WRITE( RTC_HOURS, hour + pm);
276        RTC_WRITE( RTC_DAY_OF_MONTH, day );
277        RTC_WRITE( RTC_MONTH, mon );
278        RTC_WRITE( RTC_YEAR, year );
279        if (wday >= 0) RTC_WRITE( RTC_DAY_OF_WEEK, wday );
280    }
281    RTC_WRITE( RTC_CONTROL, ctrl & ~RTC_SET );
282    local_irq_restore(flags);
283
284    if (!op) {
285        /* read: adjust values */
286
287        if (hour & 0x80) {
288	    hour &= ~0x80;
289	    pm = 1;
290	}
291
292	if (!(ctrl & RTC_DM_BINARY)) {
293	    sec = bcd2bin(sec);
294	    min = bcd2bin(min);
295	    hour = bcd2bin(hour);
296	    day = bcd2bin(day);
297	    mon = bcd2bin(mon);
298	    year = bcd2bin(year);
299	    wday = bcd2bin(wday);
300        }
301
302        if (!(ctrl & RTC_24H)) {
303	    if (!pm && hour == 12)
304		hour = 0;
305	    else if (pm && hour != 12)
306		hour += 12;
307        }
308
309        t->tm_sec  = sec;
310        t->tm_min  = min;
311        t->tm_hour = hour;
312        t->tm_mday = day;
313        t->tm_mon  = mon - 1;
314        t->tm_year = year + atari_rtc_year_offset;
315        t->tm_wday = wday - 1;
316    }
317
318    return( 0 );
319}
v6.13.7
  1/*
  2 * linux/arch/m68k/atari/time.c
  3 *
  4 * Atari time and real time clock stuff
  5 *
  6 * Assembled of parts of former atari/config.c 97-12-18 by Roman Hodek
  7 *
  8 * This file is subject to the terms and conditions of the GNU General Public
  9 * License.  See the file COPYING in the main directory of this archive
 10 * for more details.
 11 */
 12
 13#include <linux/types.h>
 14#include <linux/mc146818rtc.h>
 15#include <linux/interrupt.h>
 16#include <linux/init.h>
 17#include <linux/rtc.h>
 18#include <linux/bcd.h>
 19#include <linux/clocksource.h>
 20#include <linux/delay.h>
 21#include <linux/export.h>
 22
 23#include <asm/atariints.h>
 24#include <asm/machdep.h>
 25
 26#include "atari.h"
 27
 28DEFINE_SPINLOCK(rtc_lock);
 29EXPORT_SYMBOL_GPL(rtc_lock);
 30
 31static u64 atari_read_clk(struct clocksource *cs);
 32
 33static struct clocksource atari_clk = {
 34	.name   = "mfp",
 35	.rating = 100,
 36	.read   = atari_read_clk,
 37	.mask   = CLOCKSOURCE_MASK(32),
 38	.flags  = CLOCK_SOURCE_IS_CONTINUOUS,
 39};
 40
 41static u32 clk_total;
 42static u8 last_timer_count;
 43
 44static irqreturn_t mfp_timer_c_handler(int irq, void *dev_id)
 45{
 46	unsigned long flags;
 47
 48	local_irq_save(flags);
 49	do {
 50		last_timer_count = st_mfp.tim_dt_c;
 51	} while (last_timer_count == 1);
 52	clk_total += INT_TICKS;
 53	legacy_timer_tick(1);
 54	timer_heartbeat();
 55	local_irq_restore(flags);
 56
 57	return IRQ_HANDLED;
 58}
 59
 60void __init
 61atari_sched_init(void)
 62{
 63    /* set Timer C data Register */
 64    st_mfp.tim_dt_c = INT_TICKS;
 65    /* start timer C, div = 1:100 */
 66    st_mfp.tim_ct_cd = (st_mfp.tim_ct_cd & 15) | 0x60;
 67    /* install interrupt service routine for MFP Timer C */
 68    if (request_irq(IRQ_MFP_TIMC, mfp_timer_c_handler, IRQF_TIMER, "timer",
 69                    NULL))
 70	pr_err("Couldn't register timer interrupt\n");
 71
 72    clocksource_register_hz(&atari_clk, INT_CLK);
 73}
 74
 75/* ++andreas: gettimeoffset fixed to check for pending interrupt */
 76
 77static u64 atari_read_clk(struct clocksource *cs)
 78{
 79	unsigned long flags;
 80	u8 count;
 81	u32 ticks;
 82
 83	local_irq_save(flags);
 84	/* Ensure that the count is monotonically decreasing, even though
 85	 * the result may briefly stop changing after counter wrap-around.
 86	 */
 87	count = min(st_mfp.tim_dt_c, last_timer_count);
 88	last_timer_count = count;
 89
 90	ticks = INT_TICKS - count;
 91	ticks += clk_total;
 92	local_irq_restore(flags);
 93
 94	return ticks;
 95}
 96
 97
 98static void mste_read(struct MSTE_RTC *val)
 99{
100#define COPY(v) val->v=(mste_rtc.v & 0xf)
101	do {
102		COPY(sec_ones) ; COPY(sec_tens) ; COPY(min_ones) ;
103		COPY(min_tens) ; COPY(hr_ones) ; COPY(hr_tens) ;
104		COPY(weekday) ; COPY(day_ones) ; COPY(day_tens) ;
105		COPY(mon_ones) ; COPY(mon_tens) ; COPY(year_ones) ;
106		COPY(year_tens) ;
107	/* prevent from reading the clock while it changed */
108	} while (val->sec_ones != (mste_rtc.sec_ones & 0xf));
109#undef COPY
110}
111
112static void mste_write(struct MSTE_RTC *val)
113{
114#define COPY(v) mste_rtc.v=val->v
115	do {
116		COPY(sec_ones) ; COPY(sec_tens) ; COPY(min_ones) ;
117		COPY(min_tens) ; COPY(hr_ones) ; COPY(hr_tens) ;
118		COPY(weekday) ; COPY(day_ones) ; COPY(day_tens) ;
119		COPY(mon_ones) ; COPY(mon_tens) ; COPY(year_ones) ;
120		COPY(year_tens) ;
121	/* prevent from writing the clock while it changed */
122	} while (val->sec_ones != (mste_rtc.sec_ones & 0xf));
123#undef COPY
124}
125
126#define	RTC_READ(reg)				\
127    ({	unsigned char	__val;			\
128		(void) atari_writeb(reg,&tt_rtc.regsel);	\
129		__val = tt_rtc.data;		\
130		__val;				\
131	})
132
133#define	RTC_WRITE(reg,val)			\
134    do {					\
135		atari_writeb(reg,&tt_rtc.regsel);	\
136		tt_rtc.data = (val);		\
137	} while(0)
138
139
140#define HWCLK_POLL_INTERVAL	5
141
142int atari_mste_hwclk( int op, struct rtc_time *t )
143{
144    int hour, year;
145    int hr24=0;
146    struct MSTE_RTC val;
147
148    mste_rtc.mode=(mste_rtc.mode | 1);
149    hr24=mste_rtc.mon_tens & 1;
150    mste_rtc.mode=(mste_rtc.mode & ~1);
151
152    if (op) {
153        /* write: prepare values */
154
155        val.sec_ones = t->tm_sec % 10;
156        val.sec_tens = t->tm_sec / 10;
157        val.min_ones = t->tm_min % 10;
158        val.min_tens = t->tm_min / 10;
159        hour = t->tm_hour;
160        if (!hr24) {
161	    if (hour > 11)
162		hour += 20 - 12;
163	    if (hour == 0 || hour == 20)
164		hour += 12;
165        }
166        val.hr_ones = hour % 10;
167        val.hr_tens = hour / 10;
168        val.day_ones = t->tm_mday % 10;
169        val.day_tens = t->tm_mday / 10;
170        val.mon_ones = (t->tm_mon+1) % 10;
171        val.mon_tens = (t->tm_mon+1) / 10;
172        year = t->tm_year - 80;
173        val.year_ones = year % 10;
174        val.year_tens = year / 10;
175        val.weekday = t->tm_wday;
176        mste_write(&val);
177        mste_rtc.mode=(mste_rtc.mode | 1);
178        val.year_ones = (year % 4);	/* leap year register */
179        mste_rtc.mode=(mste_rtc.mode & ~1);
180    }
181    else {
182        mste_read(&val);
183        t->tm_sec = val.sec_ones + val.sec_tens * 10;
184        t->tm_min = val.min_ones + val.min_tens * 10;
185        hour = val.hr_ones + val.hr_tens * 10;
186	if (!hr24) {
187	    if (hour == 12 || hour == 12 + 20)
188		hour -= 12;
189	    if (hour >= 20)
190                hour += 12 - 20;
191        }
192	t->tm_hour = hour;
193	t->tm_mday = val.day_ones + val.day_tens * 10;
194        t->tm_mon  = val.mon_ones + val.mon_tens * 10 - 1;
195        t->tm_year = val.year_ones + val.year_tens * 10 + 80;
196        t->tm_wday = val.weekday;
197    }
198    return 0;
199}
200
201int atari_tt_hwclk( int op, struct rtc_time *t )
202{
203    int sec=0, min=0, hour=0, day=0, mon=0, year=0, wday=0;
204    unsigned long	flags;
205    unsigned char	ctrl;
206    int pm = 0;
207
208    ctrl = RTC_READ(RTC_CONTROL); /* control registers are
209                                   * independent from the UIP */
210
211    if (op) {
212        /* write: prepare values */
213
214        sec  = t->tm_sec;
215        min  = t->tm_min;
216        hour = t->tm_hour;
217        day  = t->tm_mday;
218        mon  = t->tm_mon + 1;
219        year = t->tm_year - atari_rtc_year_offset;
220        wday = t->tm_wday + (t->tm_wday >= 0);
221
222        if (!(ctrl & RTC_24H)) {
223	    if (hour > 11) {
224		pm = 0x80;
225		if (hour != 12)
226		    hour -= 12;
227	    }
228	    else if (hour == 0)
229		hour = 12;
230        }
231
232        if (!(ctrl & RTC_DM_BINARY)) {
233	    sec = bin2bcd(sec);
234	    min = bin2bcd(min);
235	    hour = bin2bcd(hour);
236	    day = bin2bcd(day);
237	    mon = bin2bcd(mon);
238	    year = bin2bcd(year);
239	    if (wday >= 0)
240		wday = bin2bcd(wday);
241        }
242    }
243
244    /* Reading/writing the clock registers is a bit critical due to
245     * the regular update cycle of the RTC. While an update is in
246     * progress, registers 0..9 shouldn't be touched.
247     * The problem is solved like that: If an update is currently in
248     * progress (the UIP bit is set), the process sleeps for a while
249     * (50ms). This really should be enough, since the update cycle
250     * normally needs 2 ms.
251     * If the UIP bit reads as 0, we have at least 244 usecs until the
252     * update starts. This should be enough... But to be sure,
253     * additionally the RTC_SET bit is set to prevent an update cycle.
254     */
255
256    while( RTC_READ(RTC_FREQ_SELECT) & RTC_UIP ) {
257	if (in_atomic() || irqs_disabled())
258	    mdelay(1);
259	else
260	    schedule_timeout_interruptible(HWCLK_POLL_INTERVAL);
261    }
262
263    local_irq_save(flags);
264    RTC_WRITE( RTC_CONTROL, ctrl | RTC_SET );
265    if (!op) {
266        sec  = RTC_READ( RTC_SECONDS );
267        min  = RTC_READ( RTC_MINUTES );
268        hour = RTC_READ( RTC_HOURS );
269        day  = RTC_READ( RTC_DAY_OF_MONTH );
270        mon  = RTC_READ( RTC_MONTH );
271        year = RTC_READ( RTC_YEAR );
272        wday = RTC_READ( RTC_DAY_OF_WEEK );
273    }
274    else {
275        RTC_WRITE( RTC_SECONDS, sec );
276        RTC_WRITE( RTC_MINUTES, min );
277        RTC_WRITE( RTC_HOURS, hour + pm);
278        RTC_WRITE( RTC_DAY_OF_MONTH, day );
279        RTC_WRITE( RTC_MONTH, mon );
280        RTC_WRITE( RTC_YEAR, year );
281        if (wday >= 0) RTC_WRITE( RTC_DAY_OF_WEEK, wday );
282    }
283    RTC_WRITE( RTC_CONTROL, ctrl & ~RTC_SET );
284    local_irq_restore(flags);
285
286    if (!op) {
287        /* read: adjust values */
288
289        if (hour & 0x80) {
290	    hour &= ~0x80;
291	    pm = 1;
292	}
293
294	if (!(ctrl & RTC_DM_BINARY)) {
295	    sec = bcd2bin(sec);
296	    min = bcd2bin(min);
297	    hour = bcd2bin(hour);
298	    day = bcd2bin(day);
299	    mon = bcd2bin(mon);
300	    year = bcd2bin(year);
301	    wday = bcd2bin(wday);
302        }
303
304        if (!(ctrl & RTC_24H)) {
305	    if (!pm && hour == 12)
306		hour = 0;
307	    else if (pm && hour != 12)
308		hour += 12;
309        }
310
311        t->tm_sec  = sec;
312        t->tm_min  = min;
313        t->tm_hour = hour;
314        t->tm_mday = day;
315        t->tm_mon  = mon - 1;
316        t->tm_year = year + atari_rtc_year_offset;
317        t->tm_wday = wday - 1;
318    }
319
320    return( 0 );
321}