xref: /openbmc/linux/arch/sh/kernel/time.c (revision 1da177e4)
1 /*
2  *  arch/sh/kernel/time.c
3  *
4  *  Copyright (C) 1999  Tetsuya Okada & Niibe Yutaka
5  *  Copyright (C) 2000  Philipp Rumpf <prumpf@tux.org>
6  *  Copyright (C) 2002, 2003, 2004  Paul Mundt
7  *  Copyright (C) 2002  M. R. Brown  <mrbrown@linux-sh.org>
8  *
9  *  Some code taken from i386 version.
10  *    Copyright (C) 1991, 1992, 1995  Linus Torvalds
11  */
12 
13 #include <linux/config.h>
14 #include <linux/errno.h>
15 #include <linux/module.h>
16 #include <linux/sched.h>
17 #include <linux/kernel.h>
18 #include <linux/param.h>
19 #include <linux/string.h>
20 #include <linux/mm.h>
21 #include <linux/interrupt.h>
22 #include <linux/time.h>
23 #include <linux/delay.h>
24 #include <linux/init.h>
25 #include <linux/smp.h>
26 #include <linux/profile.h>
27 
28 #include <asm/processor.h>
29 #include <asm/uaccess.h>
30 #include <asm/io.h>
31 #include <asm/irq.h>
32 #include <asm/delay.h>
33 #include <asm/machvec.h>
34 #include <asm/rtc.h>
35 #include <asm/freq.h>
36 #include <asm/cpu/timer.h>
37 #ifdef CONFIG_SH_KGDB
38 #include <asm/kgdb.h>
39 #endif
40 
41 #include <linux/timex.h>
42 #include <linux/irq.h>
43 
44 #define TMU_TOCR_INIT	0x00
45 #define TMU0_TCR_INIT	0x0020
46 #define TMU_TSTR_INIT	1
47 
48 #define TMU0_TCR_CALIB	0x0000
49 
50 #ifdef CONFIG_CPU_SUBTYPE_ST40STB1
51 #define CLOCKGEN_MEMCLKCR 0xbb040038
52 #define MEMCLKCR_RATIO_MASK 0x7
53 #endif /* CONFIG_CPU_SUBTYPE_ST40STB1 */
54 
55 extern unsigned long wall_jiffies;
56 #define TICK_SIZE (tick_nsec / 1000)
57 DEFINE_SPINLOCK(tmu0_lock);
58 
59 u64 jiffies_64 = INITIAL_JIFFIES;
60 
61 EXPORT_SYMBOL(jiffies_64);
62 
63 /* XXX: Can we initialize this in a routine somewhere?  Dreamcast doesn't want
64  * these routines anywhere... */
65 #ifdef CONFIG_SH_RTC
66 void (*rtc_get_time)(struct timespec *) = sh_rtc_gettimeofday;
67 int (*rtc_set_time)(const time_t) = sh_rtc_settimeofday;
68 #else
69 void (*rtc_get_time)(struct timespec *);
70 int (*rtc_set_time)(const time_t);
71 #endif
72 
73 #if defined(CONFIG_CPU_SUBTYPE_SH7300)
74 static int md_table[] = { 1, 2, 3, 4, 6, 8, 12 };
75 #endif
76 #if defined(CONFIG_CPU_SH3)
77 static int stc_multipliers[] = { 1, 2, 3, 4, 6, 1, 1, 1 };
78 static int stc_values[]      = { 0, 1, 4, 2, 5, 0, 0, 0 };
79 #define bfc_divisors stc_multipliers
80 #define bfc_values stc_values
81 static int ifc_divisors[]    = { 1, 2, 3, 4, 1, 1, 1, 1 };
82 static int ifc_values[]      = { 0, 1, 4, 2, 0, 0, 0, 0 };
83 static int pfc_divisors[]    = { 1, 2, 3, 4, 6, 1, 1, 1 };
84 static int pfc_values[]      = { 0, 1, 4, 2, 5, 0, 0, 0 };
85 #elif defined(CONFIG_CPU_SH4)
86 #if defined(CONFIG_CPU_SUBTYPE_SH73180)
87 static int ifc_divisors[] = { 1, 2, 3, 4, 6, 8, 12, 16 };
88 static int ifc_values[] = { 0, 1, 2, 3, 4, 5, 6, 7 };
89 #define bfc_divisors ifc_divisors	/* Same */
90 #define bfc_values ifc_values
91 #define pfc_divisors ifc_divisors	/* Same */
92 #define pfc_values ifc_values
93 #else
94 static int ifc_divisors[] = { 1, 2, 3, 4, 6, 8, 1, 1 };
95 static int ifc_values[]   = { 0, 1, 2, 3, 0, 4, 0, 5 };
96 #define bfc_divisors ifc_divisors	/* Same */
97 #define bfc_values ifc_values
98 static int pfc_divisors[] = { 2, 3, 4, 6, 8, 2, 2, 2 };
99 static int pfc_values[]   = { 0, 0, 1, 2, 0, 3, 0, 4 };
100 #endif
101 #else
102 #error "Unknown ifc/bfc/pfc/stc values for this processor"
103 #endif
104 
105 /*
106  * Scheduler clock - returns current time in nanosec units.
107  */
108 unsigned long long sched_clock(void)
109 {
110 	return (unsigned long long)jiffies * (1000000000 / HZ);
111 }
112 
113 static unsigned long do_gettimeoffset(void)
114 {
115 	int count;
116 	unsigned long flags;
117 
118 	static int count_p = 0x7fffffff;    /* for the first call after boot */
119 	static unsigned long jiffies_p = 0;
120 
121 	/*
122 	 * cache volatile jiffies temporarily; we have IRQs turned off.
123 	 */
124 	unsigned long jiffies_t;
125 
126 	spin_lock_irqsave(&tmu0_lock, flags);
127 	/* timer count may underflow right here */
128 	count = ctrl_inl(TMU0_TCNT);	/* read the latched count */
129 
130 	jiffies_t = jiffies;
131 
132 	/*
133 	 * avoiding timer inconsistencies (they are rare, but they happen)...
134 	 * there is one kind of problem that must be avoided here:
135 	 *  1. the timer counter underflows
136 	 */
137 
138 	if( jiffies_t == jiffies_p ) {
139 		if( count > count_p ) {
140 			/* the nutcase */
141 
142 			if(ctrl_inw(TMU0_TCR) & 0x100) { /* Check UNF bit */
143 				/*
144 				 * We cannot detect lost timer interrupts ...
145 				 * well, that's why we call them lost, don't we? :)
146 				 * [hmm, on the Pentium and Alpha we can ... sort of]
147 				 */
148 				count -= LATCH;
149 			} else {
150 				printk("do_slow_gettimeoffset(): hardware timer problem?\n");
151 			}
152 		}
153 	} else
154 		jiffies_p = jiffies_t;
155 
156 	count_p = count;
157 	spin_unlock_irqrestore(&tmu0_lock, flags);
158 
159 	count = ((LATCH-1) - count) * TICK_SIZE;
160 	count = (count + LATCH/2) / LATCH;
161 
162 	return count;
163 }
164 
165 void do_gettimeofday(struct timeval *tv)
166 {
167 	unsigned long seq;
168 	unsigned long usec, sec;
169 	unsigned long lost;
170 
171 	do {
172 		seq = read_seqbegin(&xtime_lock);
173 		usec = do_gettimeoffset();
174 
175 		lost = jiffies - wall_jiffies;
176 		if (lost)
177 			usec += lost * (1000000 / HZ);
178 
179 		sec = xtime.tv_sec;
180 		usec += xtime.tv_nsec / 1000;
181 	} while (read_seqretry(&xtime_lock, seq));
182 
183 	while (usec >= 1000000) {
184 		usec -= 1000000;
185 		sec++;
186 	}
187 
188 	tv->tv_sec = sec;
189 	tv->tv_usec = usec;
190 }
191 
192 EXPORT_SYMBOL(do_gettimeofday);
193 
194 int do_settimeofday(struct timespec *tv)
195 {
196 	time_t wtm_sec, sec = tv->tv_sec;
197 	long wtm_nsec, nsec = tv->tv_nsec;
198 
199 	if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC)
200 		return -EINVAL;
201 
202 	write_seqlock_irq(&xtime_lock);
203 	/*
204 	 * This is revolting. We need to set "xtime" correctly. However, the
205 	 * value in this location is the value at the most recent update of
206 	 * wall time.  Discover what correction gettimeofday() would have
207 	 * made, and then undo it!
208 	 */
209 	nsec -= 1000 * (do_gettimeoffset() +
210 				(jiffies - wall_jiffies) * (1000000 / HZ));
211 
212 	wtm_sec  = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec);
213 	wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec);
214 
215 	set_normalized_timespec(&xtime, sec, nsec);
216 	set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec);
217 
218 	time_adjust = 0;		/* stop active adjtime() */
219 	time_status |= STA_UNSYNC;
220 	time_maxerror = NTP_PHASE_LIMIT;
221 	time_esterror = NTP_PHASE_LIMIT;
222 	write_sequnlock_irq(&xtime_lock);
223 	clock_was_set();
224 
225 	return 0;
226 }
227 
228 EXPORT_SYMBOL(do_settimeofday);
229 
230 /* last time the RTC clock got updated */
231 static long last_rtc_update;
232 
233 /*
234  * timer_interrupt() needs to keep up the real-time clock,
235  * as well as call the "do_timer()" routine every clocktick
236  */
237 static inline void do_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
238 {
239 	do_timer(regs);
240 #ifndef CONFIG_SMP
241 	update_process_times(user_mode(regs));
242 #endif
243 	profile_tick(CPU_PROFILING, regs);
244 
245 #ifdef CONFIG_HEARTBEAT
246 	if (sh_mv.mv_heartbeat != NULL)
247 		sh_mv.mv_heartbeat();
248 #endif
249 
250 	/*
251 	 * If we have an externally synchronized Linux clock, then update
252 	 * RTC clock accordingly every ~11 minutes. Set_rtc_mmss() has to be
253 	 * called as close as possible to 500 ms before the new second starts.
254 	 */
255 	if ((time_status & STA_UNSYNC) == 0 &&
256 	    xtime.tv_sec > last_rtc_update + 660 &&
257 	    (xtime.tv_nsec / 1000) >= 500000 - ((unsigned) TICK_SIZE) / 2 &&
258 	    (xtime.tv_nsec / 1000) <= 500000 + ((unsigned) TICK_SIZE) / 2) {
259 		if (rtc_set_time(xtime.tv_sec) == 0)
260 			last_rtc_update = xtime.tv_sec;
261 		else
262 			last_rtc_update = xtime.tv_sec - 600; /* do it again in 60 s */
263 	}
264 }
265 
266 /*
267  * This is the same as the above, except we _also_ save the current
268  * Time Stamp Counter value at the time of the timer interrupt, so that
269  * we later on can estimate the time of day more exactly.
270  */
271 static irqreturn_t timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
272 {
273 	unsigned long timer_status;
274 
275 	/* Clear UNF bit */
276 	timer_status = ctrl_inw(TMU0_TCR);
277 	timer_status &= ~0x100;
278 	ctrl_outw(timer_status, TMU0_TCR);
279 
280 	/*
281 	 * Here we are in the timer irq handler. We just have irqs locally
282 	 * disabled but we don't know if the timer_bh is running on the other
283 	 * CPU. We need to avoid to SMP race with it. NOTE: we don' t need
284 	 * the irq version of write_lock because as just said we have irq
285 	 * locally disabled. -arca
286 	 */
287 	write_seqlock(&xtime_lock);
288 	do_timer_interrupt(irq, NULL, regs);
289 	write_sequnlock(&xtime_lock);
290 
291 	return IRQ_HANDLED;
292 }
293 
294 /*
295  * Hah!  We'll see if this works (switching from usecs to nsecs).
296  */
297 static unsigned int __init get_timer_frequency(void)
298 {
299 	u32 freq;
300 	struct timespec ts1, ts2;
301 	unsigned long diff_nsec;
302 	unsigned long factor;
303 
304 	/* Setup the timer:  We don't want to generate interrupts, just
305 	 * have it count down at its natural rate.
306 	 */
307 	ctrl_outb(0, TMU_TSTR);
308 #if !defined(CONFIG_CPU_SUBTYPE_SH7300)
309 	ctrl_outb(TMU_TOCR_INIT, TMU_TOCR);
310 #endif
311 	ctrl_outw(TMU0_TCR_CALIB, TMU0_TCR);
312 	ctrl_outl(0xffffffff, TMU0_TCOR);
313 	ctrl_outl(0xffffffff, TMU0_TCNT);
314 
315 	rtc_get_time(&ts2);
316 
317 	do {
318 		rtc_get_time(&ts1);
319 	} while (ts1.tv_nsec == ts2.tv_nsec && ts1.tv_sec == ts2.tv_sec);
320 
321 	/* actually start the timer */
322 	ctrl_outb(TMU_TSTR_INIT, TMU_TSTR);
323 
324 	do {
325 		rtc_get_time(&ts2);
326 	} while (ts1.tv_nsec == ts2.tv_nsec && ts1.tv_sec == ts2.tv_sec);
327 
328 	freq = 0xffffffff - ctrl_inl(TMU0_TCNT);
329 	if (ts2.tv_nsec < ts1.tv_nsec) {
330 		ts2.tv_nsec += 1000000000;
331 		ts2.tv_sec--;
332 	}
333 
334 	diff_nsec = (ts2.tv_sec - ts1.tv_sec) * 1000000000 + (ts2.tv_nsec - ts1.tv_nsec);
335 
336 	/* this should work well if the RTC has a precision of n Hz, where
337 	 * n is an integer.  I don't think we have to worry about the other
338 	 * cases. */
339 	factor = (1000000000 + diff_nsec/2) / diff_nsec;
340 
341 	if (factor * diff_nsec > 1100000000 ||
342 	    factor * diff_nsec <  900000000)
343 		panic("weird RTC (diff_nsec %ld)", diff_nsec);
344 
345 	return freq * factor;
346 }
347 
348 void (*board_time_init)(void);
349 void (*board_timer_setup)(struct irqaction *irq);
350 
351 static unsigned int sh_pclk_freq __initdata = CONFIG_SH_PCLK_FREQ;
352 
353 static int __init sh_pclk_setup(char *str)
354 {
355         unsigned int freq;
356 
357 	if (get_option(&str, &freq))
358 		sh_pclk_freq = freq;
359 
360 	return 1;
361 }
362 __setup("sh_pclk=", sh_pclk_setup);
363 
364 static struct irqaction irq0  = { timer_interrupt, SA_INTERRUPT, CPU_MASK_NONE, "timer", NULL, NULL};
365 
366 void get_current_frequency_divisors(unsigned int *ifc, unsigned int *bfc, unsigned int *pfc)
367 {
368 	unsigned int frqcr = ctrl_inw(FRQCR);
369 
370 #if defined(CONFIG_CPU_SH3)
371 #if defined(CONFIG_CPU_SUBTYPE_SH7300)
372 	*ifc = md_table[((frqcr & 0x0070) >> 4)];
373 	*bfc = md_table[((frqcr & 0x0700) >> 8)];
374 	*pfc = md_table[frqcr & 0x0007];
375 #elif defined(CONFIG_CPU_SUBTYPE_SH7705)
376 	*bfc = stc_multipliers[(frqcr & 0x0300) >> 8];
377 	*ifc = ifc_divisors[(frqcr & 0x0030) >> 4];
378 	*pfc = pfc_divisors[frqcr & 0x0003];
379 #else
380 	unsigned int tmp;
381 
382 	tmp  = (frqcr & 0x8000) >> 13;
383 	tmp |= (frqcr & 0x0030) >>  4;
384 	*bfc = stc_multipliers[tmp];
385 	tmp  = (frqcr & 0x4000)  >> 12;
386 	tmp |= (frqcr & 0x000c) >> 2;
387 	*ifc = ifc_divisors[tmp];
388 	tmp  = (frqcr & 0x2000) >> 11;
389 	tmp |= frqcr & 0x0003;
390 	*pfc = pfc_divisors[tmp];
391 #endif
392 #elif defined(CONFIG_CPU_SH4)
393 #if defined(CONFIG_CPU_SUBTYPE_SH73180)
394 	*ifc = ifc_divisors[(frqcr>> 20) & 0x0007];
395 	*bfc = bfc_divisors[(frqcr>> 12) & 0x0007];
396 	*pfc = pfc_divisors[frqcr & 0x0007];
397 #else
398 	*ifc = ifc_divisors[(frqcr >> 6) & 0x0007];
399 	*bfc = bfc_divisors[(frqcr >> 3) & 0x0007];
400 	*pfc = pfc_divisors[frqcr & 0x0007];
401 #endif
402 #endif
403 }
404 
405 /*
406  * This bit of ugliness builds up accessor routines to get at both
407  * the divisors and the physical values.
408  */
409 #define _FREQ_TABLE(x) \
410 	unsigned int get_##x##_divisor(unsigned int value)	\
411 		{ return x##_divisors[value]; }			\
412 								\
413 	unsigned int get_##x##_value(unsigned int divisor)	\
414 		{ return x##_values[(divisor - 1)]; }
415 
416 _FREQ_TABLE(ifc);
417 _FREQ_TABLE(bfc);
418 _FREQ_TABLE(pfc);
419 
420 #ifdef CONFIG_CPU_SUBTYPE_ST40STB1
421 
422 /*
423  * The ST40 divisors are totally different so we set the cpu data
424  * clocks using a different algorithm
425  *
426  * I've just plugged this from the 2.4 code
427  *	- Alex Bennee <kernel-hacker@bennee.com>
428  */
429 #define CCN_PVR_CHIP_SHIFT 24
430 #define CCN_PVR_CHIP_MASK  0xff
431 #define CCN_PVR_CHIP_ST40STB1 0x4
432 
433 
434 struct frqcr_data {
435 	unsigned short frqcr;
436 
437 	struct {
438 		unsigned char multiplier;
439 		unsigned char divisor;
440 	} factor[3];
441 };
442 
443 static struct frqcr_data st40_frqcr_table[] = {
444 	{ 0x000, {{1,1}, {1,1}, {1,2}}},
445 	{ 0x002, {{1,1}, {1,1}, {1,4}}},
446 	{ 0x004, {{1,1}, {1,1}, {1,8}}},
447 	{ 0x008, {{1,1}, {1,2}, {1,2}}},
448 	{ 0x00A, {{1,1}, {1,2}, {1,4}}},
449 	{ 0x00C, {{1,1}, {1,2}, {1,8}}},
450 	{ 0x011, {{1,1}, {2,3}, {1,6}}},
451 	{ 0x013, {{1,1}, {2,3}, {1,3}}},
452 	{ 0x01A, {{1,1}, {1,2}, {1,4}}},
453 	{ 0x01C, {{1,1}, {1,2}, {1,8}}},
454 	{ 0x023, {{1,1}, {2,3}, {1,3}}},
455 	{ 0x02C, {{1,1}, {1,2}, {1,8}}},
456 	{ 0x048, {{1,2}, {1,2}, {1,4}}},
457 	{ 0x04A, {{1,2}, {1,2}, {1,6}}},
458 	{ 0x04C, {{1,2}, {1,2}, {1,8}}},
459 	{ 0x05A, {{1,2}, {1,3}, {1,6}}},
460 	{ 0x05C, {{1,2}, {1,3}, {1,6}}},
461 	{ 0x063, {{1,2}, {1,4}, {1,4}}},
462 	{ 0x06C, {{1,2}, {1,4}, {1,8}}},
463 	{ 0x091, {{1,3}, {1,3}, {1,6}}},
464 	{ 0x093, {{1,3}, {1,3}, {1,6}}},
465 	{ 0x0A3, {{1,3}, {1,6}, {1,6}}},
466 	{ 0x0DA, {{1,4}, {1,4}, {1,8}}},
467 	{ 0x0DC, {{1,4}, {1,4}, {1,8}}},
468 	{ 0x0EC, {{1,4}, {1,8}, {1,8}}},
469 	{ 0x123, {{1,4}, {1,4}, {1,8}}},
470 	{ 0x16C, {{1,4}, {1,8}, {1,8}}},
471 };
472 
473 struct memclk_data {
474 	unsigned char multiplier;
475 	unsigned char divisor;
476 };
477 
478 static struct memclk_data st40_memclk_table[8] = {
479 	{1,1},	// 000
480 	{1,2},	// 001
481 	{1,3},	// 010
482 	{2,3},	// 011
483 	{1,4},	// 100
484 	{1,6},	// 101
485 	{1,8},	// 110
486 	{1,8}	// 111
487 };
488 
489 static void st40_specific_time_init(unsigned int module_clock, unsigned short frqcr)
490 {
491 	unsigned int cpu_clock, master_clock, bus_clock, memory_clock;
492 	struct frqcr_data *d;
493 	int a;
494 	unsigned long memclkcr;
495 	struct memclk_data *e;
496 
497 	for (a = 0; a < ARRAY_SIZE(st40_frqcr_table); a++) {
498 		d = &st40_frqcr_table[a];
499 
500 		if (d->frqcr == (frqcr & 0x1ff))
501 			break;
502 	}
503 
504 	if (a == ARRAY_SIZE(st40_frqcr_table)) {
505 		d = st40_frqcr_table;
506 
507 		printk("ERROR: Unrecognised FRQCR value (0x%x), "
508 		       "using default multipliers\n", frqcr);
509 	}
510 
511 	memclkcr = ctrl_inl(CLOCKGEN_MEMCLKCR);
512 	e = &st40_memclk_table[memclkcr & MEMCLKCR_RATIO_MASK];
513 
514 	printk(KERN_INFO "Clock multipliers: CPU: %d/%d Bus: %d/%d "
515 	       "Mem: %d/%d Periph: %d/%d\n",
516 	       d->factor[0].multiplier, d->factor[0].divisor,
517 	       d->factor[1].multiplier, d->factor[1].divisor,
518 	       e->multiplier,           e->divisor,
519 	       d->factor[2].multiplier, d->factor[2].divisor);
520 
521 	master_clock = module_clock * d->factor[2].divisor
522 				    / d->factor[2].multiplier;
523 	bus_clock    = master_clock * d->factor[1].multiplier
524 				    / d->factor[1].divisor;
525 	memory_clock = master_clock * e->multiplier
526 				    / e->divisor;
527 	cpu_clock    = master_clock * d->factor[0].multiplier
528 				    / d->factor[0].divisor;
529 
530 	current_cpu_data.cpu_clock    = cpu_clock;
531 	current_cpu_data.master_clock = master_clock;
532 	current_cpu_data.bus_clock    = bus_clock;
533 	current_cpu_data.memory_clock = memory_clock;
534 	current_cpu_data.module_clock = module_clock;
535 }
536 #endif
537 
538 void __init time_init(void)
539 {
540 	unsigned int timer_freq = 0;
541 	unsigned int ifc, pfc, bfc;
542 	unsigned long interval;
543 #ifdef CONFIG_CPU_SUBTYPE_ST40STB1
544 	unsigned long pvr;
545 	unsigned short frqcr;
546 #endif
547 
548 	if (board_time_init)
549 		board_time_init();
550 
551 	/*
552 	 * If we don't have an RTC (such as with the SH7300), don't attempt to
553 	 * probe the timer frequency. Rely on an either hardcoded peripheral
554 	 * clock value, or on the sh_pclk command line option. Note that we
555 	 * still need to have CONFIG_SH_PCLK_FREQ set in order for things like
556 	 * CLOCK_TICK_RATE to be sane.
557 	 */
558 	current_cpu_data.module_clock = sh_pclk_freq;
559 
560 #ifdef CONFIG_SH_PCLK_CALC
561 	/* XXX: Switch this over to a more generic test. */
562 	{
563 		unsigned int freq;
564 
565 		/*
566 		 * If we've specified a peripheral clock frequency, and we have
567 		 * an RTC, compare it against the autodetected value. Complain
568 		 * if there's a mismatch.
569 		 */
570 		timer_freq = get_timer_frequency();
571 		freq = timer_freq * 4;
572 
573 		if (sh_pclk_freq && (sh_pclk_freq/100*99 > freq || sh_pclk_freq/100*101 < freq)) {
574 			printk(KERN_NOTICE "Calculated peripheral clock value "
575 			       "%d differs from sh_pclk value %d, fixing..\n",
576 			       freq, sh_pclk_freq);
577 			current_cpu_data.module_clock = freq;
578 		}
579 	}
580 #endif
581 
582 #ifdef CONFIG_CPU_SUBTYPE_ST40STB1
583 	/* XXX: Update ST40 code to use board_time_init() */
584 	pvr = ctrl_inl(CCN_PVR);
585 	frqcr = ctrl_inw(FRQCR);
586 	printk("time.c ST40 Probe: PVR %08lx, FRQCR %04hx\n", pvr, frqcr);
587 
588 	if (((pvr >> CCN_PVR_CHIP_SHIFT) & CCN_PVR_CHIP_MASK) == CCN_PVR_CHIP_ST40STB1)
589 		st40_specific_time_init(current_cpu_data.module_clock, frqcr);
590 	else
591 #endif
592 		get_current_frequency_divisors(&ifc, &bfc, &pfc);
593 
594 	if (rtc_get_time) {
595 		rtc_get_time(&xtime);
596 	} else {
597 		xtime.tv_sec = mktime(2000, 1, 1, 0, 0, 0);
598 		xtime.tv_nsec = 0;
599 	}
600 
601         set_normalized_timespec(&wall_to_monotonic,
602                                 -xtime.tv_sec, -xtime.tv_nsec);
603 
604 	if (board_timer_setup) {
605 		board_timer_setup(&irq0);
606 	} else {
607 		setup_irq(TIMER_IRQ, &irq0);
608 	}
609 
610 	/*
611 	 * for ST40 chips the current_cpu_data should already be set
612 	 * so not having valid pfc/bfc/ifc shouldn't be a problem
613 	 */
614 	if (!current_cpu_data.master_clock)
615 		current_cpu_data.master_clock = current_cpu_data.module_clock * pfc;
616 	if (!current_cpu_data.bus_clock)
617 		current_cpu_data.bus_clock = current_cpu_data.master_clock / bfc;
618 	if (!current_cpu_data.cpu_clock)
619 		current_cpu_data.cpu_clock = current_cpu_data.master_clock / ifc;
620 
621 	printk("CPU clock: %d.%02dMHz\n",
622 	       (current_cpu_data.cpu_clock / 1000000),
623 	       (current_cpu_data.cpu_clock % 1000000)/10000);
624 	printk("Bus clock: %d.%02dMHz\n",
625 	       (current_cpu_data.bus_clock / 1000000),
626 	       (current_cpu_data.bus_clock % 1000000)/10000);
627 #ifdef CONFIG_CPU_SUBTYPE_ST40STB1
628 	printk("Memory clock: %d.%02dMHz\n",
629 	       (current_cpu_data.memory_clock / 1000000),
630 	       (current_cpu_data.memory_clock % 1000000)/10000);
631 #endif
632 	printk("Module clock: %d.%02dMHz\n",
633 	       (current_cpu_data.module_clock / 1000000),
634 	       (current_cpu_data.module_clock % 1000000)/10000);
635 
636 	interval = (current_cpu_data.module_clock/4 + HZ/2) / HZ;
637 
638 	printk("Interval = %ld\n", interval);
639 
640 	/* Start TMU0 */
641 	ctrl_outb(0, TMU_TSTR);
642 #if !defined(CONFIG_CPU_SUBTYPE_SH7300)
643 	ctrl_outb(TMU_TOCR_INIT, TMU_TOCR);
644 #endif
645 	ctrl_outw(TMU0_TCR_INIT, TMU0_TCR);
646 	ctrl_outl(interval, TMU0_TCOR);
647 	ctrl_outl(interval, TMU0_TCNT);
648 	ctrl_outb(TMU_TSTR_INIT, TMU_TSTR);
649 
650 #if defined(CONFIG_SH_KGDB)
651 	/*
652 	 * Set up kgdb as requested. We do it here because the serial
653 	 * init uses the timer vars we just set up for figuring baud.
654 	 */
655 	kgdb_init();
656 #endif
657 }
658