xref: /linux/arch/sparc/kernel/time_64.c (revision f3539c12d8196ce0a1993364d30b3a18908470d1)
1 /* time.c: UltraSparc timer and TOD clock support.
2  *
3  * Copyright (C) 1997, 2008 David S. Miller (davem@davemloft.net)
4  * Copyright (C) 1998 Eddie C. Dost   (ecd@skynet.be)
5  *
6  * Based largely on code which is:
7  *
8  * Copyright (C) 1996 Thomas K. Dyas (tdyas@eden.rutgers.edu)
9  */
10 
11 #include <linux/errno.h>
12 #include <linux/export.h>
13 #include <linux/sched.h>
14 #include <linux/kernel.h>
15 #include <linux/param.h>
16 #include <linux/string.h>
17 #include <linux/mm.h>
18 #include <linux/interrupt.h>
19 #include <linux/time.h>
20 #include <linux/timex.h>
21 #include <linux/init.h>
22 #include <linux/ioport.h>
23 #include <linux/mc146818rtc.h>
24 #include <linux/delay.h>
25 #include <linux/profile.h>
26 #include <linux/bcd.h>
27 #include <linux/jiffies.h>
28 #include <linux/cpufreq.h>
29 #include <linux/percpu.h>
30 #include <linux/miscdevice.h>
31 #include <linux/rtc/m48t59.h>
32 #include <linux/kernel_stat.h>
33 #include <linux/clockchips.h>
34 #include <linux/clocksource.h>
35 #include <linux/of_device.h>
36 #include <linux/platform_device.h>
37 #include <linux/ftrace.h>
38 
39 #include <asm/oplib.h>
40 #include <asm/timer.h>
41 #include <asm/irq.h>
42 #include <asm/io.h>
43 #include <asm/prom.h>
44 #include <asm/starfire.h>
45 #include <asm/smp.h>
46 #include <asm/sections.h>
47 #include <asm/cpudata.h>
48 #include <asm/uaccess.h>
49 #include <asm/irq_regs.h>
50 
51 #include "entry.h"
52 
53 DEFINE_SPINLOCK(rtc_lock);
54 
55 #define TICK_PRIV_BIT	(1UL << 63)
56 #define TICKCMP_IRQ_BIT	(1UL << 63)
57 
58 #ifdef CONFIG_SMP
59 unsigned long profile_pc(struct pt_regs *regs)
60 {
61 	unsigned long pc = instruction_pointer(regs);
62 
63 	if (in_lock_functions(pc))
64 		return regs->u_regs[UREG_RETPC];
65 	return pc;
66 }
67 EXPORT_SYMBOL(profile_pc);
68 #endif
69 
70 static void tick_disable_protection(void)
71 {
72 	/* Set things up so user can access tick register for profiling
73 	 * purposes.  Also workaround BB_ERRATA_1 by doing a dummy
74 	 * read back of %tick after writing it.
75 	 */
76 	__asm__ __volatile__(
77 	"	ba,pt	%%xcc, 1f\n"
78 	"	 nop\n"
79 	"	.align	64\n"
80 	"1:	rd	%%tick, %%g2\n"
81 	"	add	%%g2, 6, %%g2\n"
82 	"	andn	%%g2, %0, %%g2\n"
83 	"	wrpr	%%g2, 0, %%tick\n"
84 	"	rdpr	%%tick, %%g0"
85 	: /* no outputs */
86 	: "r" (TICK_PRIV_BIT)
87 	: "g2");
88 }
89 
90 static void tick_disable_irq(void)
91 {
92 	__asm__ __volatile__(
93 	"	ba,pt	%%xcc, 1f\n"
94 	"	 nop\n"
95 	"	.align	64\n"
96 	"1:	wr	%0, 0x0, %%tick_cmpr\n"
97 	"	rd	%%tick_cmpr, %%g0"
98 	: /* no outputs */
99 	: "r" (TICKCMP_IRQ_BIT));
100 }
101 
102 static void tick_init_tick(void)
103 {
104 	tick_disable_protection();
105 	tick_disable_irq();
106 }
107 
108 static unsigned long long tick_get_tick(void)
109 {
110 	unsigned long ret;
111 
112 	__asm__ __volatile__("rd	%%tick, %0\n\t"
113 			     "mov	%0, %0"
114 			     : "=r" (ret));
115 
116 	return ret & ~TICK_PRIV_BIT;
117 }
118 
119 static int tick_add_compare(unsigned long adj)
120 {
121 	unsigned long orig_tick, new_tick, new_compare;
122 
123 	__asm__ __volatile__("rd	%%tick, %0"
124 			     : "=r" (orig_tick));
125 
126 	orig_tick &= ~TICKCMP_IRQ_BIT;
127 
128 	/* Workaround for Spitfire Errata (#54 I think??), I discovered
129 	 * this via Sun BugID 4008234, mentioned in Solaris-2.5.1 patch
130 	 * number 103640.
131 	 *
132 	 * On Blackbird writes to %tick_cmpr can fail, the
133 	 * workaround seems to be to execute the wr instruction
134 	 * at the start of an I-cache line, and perform a dummy
135 	 * read back from %tick_cmpr right after writing to it. -DaveM
136 	 */
137 	__asm__ __volatile__("ba,pt	%%xcc, 1f\n\t"
138 			     " add	%1, %2, %0\n\t"
139 			     ".align	64\n"
140 			     "1:\n\t"
141 			     "wr	%0, 0, %%tick_cmpr\n\t"
142 			     "rd	%%tick_cmpr, %%g0\n\t"
143 			     : "=r" (new_compare)
144 			     : "r" (orig_tick), "r" (adj));
145 
146 	__asm__ __volatile__("rd	%%tick, %0"
147 			     : "=r" (new_tick));
148 	new_tick &= ~TICKCMP_IRQ_BIT;
149 
150 	return ((long)(new_tick - (orig_tick+adj))) > 0L;
151 }
152 
153 static unsigned long tick_add_tick(unsigned long adj)
154 {
155 	unsigned long new_tick;
156 
157 	/* Also need to handle Blackbird bug here too. */
158 	__asm__ __volatile__("rd	%%tick, %0\n\t"
159 			     "add	%0, %1, %0\n\t"
160 			     "wrpr	%0, 0, %%tick\n\t"
161 			     : "=&r" (new_tick)
162 			     : "r" (adj));
163 
164 	return new_tick;
165 }
166 
167 static struct sparc64_tick_ops tick_operations __read_mostly = {
168 	.name		=	"tick",
169 	.init_tick	=	tick_init_tick,
170 	.disable_irq	=	tick_disable_irq,
171 	.get_tick	=	tick_get_tick,
172 	.add_tick	=	tick_add_tick,
173 	.add_compare	=	tick_add_compare,
174 	.softint_mask	=	1UL << 0,
175 };
176 
177 struct sparc64_tick_ops *tick_ops __read_mostly = &tick_operations;
178 EXPORT_SYMBOL(tick_ops);
179 
180 static void stick_disable_irq(void)
181 {
182 	__asm__ __volatile__(
183 	"wr	%0, 0x0, %%asr25"
184 	: /* no outputs */
185 	: "r" (TICKCMP_IRQ_BIT));
186 }
187 
188 static void stick_init_tick(void)
189 {
190 	/* Writes to the %tick and %stick register are not
191 	 * allowed on sun4v.  The Hypervisor controls that
192 	 * bit, per-strand.
193 	 */
194 	if (tlb_type != hypervisor) {
195 		tick_disable_protection();
196 		tick_disable_irq();
197 
198 		/* Let the user get at STICK too. */
199 		__asm__ __volatile__(
200 		"	rd	%%asr24, %%g2\n"
201 		"	andn	%%g2, %0, %%g2\n"
202 		"	wr	%%g2, 0, %%asr24"
203 		: /* no outputs */
204 		: "r" (TICK_PRIV_BIT)
205 		: "g1", "g2");
206 	}
207 
208 	stick_disable_irq();
209 }
210 
211 static unsigned long long stick_get_tick(void)
212 {
213 	unsigned long ret;
214 
215 	__asm__ __volatile__("rd	%%asr24, %0"
216 			     : "=r" (ret));
217 
218 	return ret & ~TICK_PRIV_BIT;
219 }
220 
221 static unsigned long stick_add_tick(unsigned long adj)
222 {
223 	unsigned long new_tick;
224 
225 	__asm__ __volatile__("rd	%%asr24, %0\n\t"
226 			     "add	%0, %1, %0\n\t"
227 			     "wr	%0, 0, %%asr24\n\t"
228 			     : "=&r" (new_tick)
229 			     : "r" (adj));
230 
231 	return new_tick;
232 }
233 
234 static int stick_add_compare(unsigned long adj)
235 {
236 	unsigned long orig_tick, new_tick;
237 
238 	__asm__ __volatile__("rd	%%asr24, %0"
239 			     : "=r" (orig_tick));
240 	orig_tick &= ~TICKCMP_IRQ_BIT;
241 
242 	__asm__ __volatile__("wr	%0, 0, %%asr25"
243 			     : /* no outputs */
244 			     : "r" (orig_tick + adj));
245 
246 	__asm__ __volatile__("rd	%%asr24, %0"
247 			     : "=r" (new_tick));
248 	new_tick &= ~TICKCMP_IRQ_BIT;
249 
250 	return ((long)(new_tick - (orig_tick+adj))) > 0L;
251 }
252 
253 static struct sparc64_tick_ops stick_operations __read_mostly = {
254 	.name		=	"stick",
255 	.init_tick	=	stick_init_tick,
256 	.disable_irq	=	stick_disable_irq,
257 	.get_tick	=	stick_get_tick,
258 	.add_tick	=	stick_add_tick,
259 	.add_compare	=	stick_add_compare,
260 	.softint_mask	=	1UL << 16,
261 };
262 
263 /* On Hummingbird the STICK/STICK_CMPR register is implemented
264  * in I/O space.  There are two 64-bit registers each, the
265  * first holds the low 32-bits of the value and the second holds
266  * the high 32-bits.
267  *
268  * Since STICK is constantly updating, we have to access it carefully.
269  *
270  * The sequence we use to read is:
271  * 1) read high
272  * 2) read low
273  * 3) read high again, if it rolled re-read both low and high again.
274  *
275  * Writing STICK safely is also tricky:
276  * 1) write low to zero
277  * 2) write high
278  * 3) write low
279  */
280 #define HBIRD_STICKCMP_ADDR	0x1fe0000f060UL
281 #define HBIRD_STICK_ADDR	0x1fe0000f070UL
282 
283 static unsigned long __hbird_read_stick(void)
284 {
285 	unsigned long ret, tmp1, tmp2, tmp3;
286 	unsigned long addr = HBIRD_STICK_ADDR+8;
287 
288 	__asm__ __volatile__("ldxa	[%1] %5, %2\n"
289 			     "1:\n\t"
290 			     "sub	%1, 0x8, %1\n\t"
291 			     "ldxa	[%1] %5, %3\n\t"
292 			     "add	%1, 0x8, %1\n\t"
293 			     "ldxa	[%1] %5, %4\n\t"
294 			     "cmp	%4, %2\n\t"
295 			     "bne,a,pn	%%xcc, 1b\n\t"
296 			     " mov	%4, %2\n\t"
297 			     "sllx	%4, 32, %4\n\t"
298 			     "or	%3, %4, %0\n\t"
299 			     : "=&r" (ret), "=&r" (addr),
300 			       "=&r" (tmp1), "=&r" (tmp2), "=&r" (tmp3)
301 			     : "i" (ASI_PHYS_BYPASS_EC_E), "1" (addr));
302 
303 	return ret;
304 }
305 
306 static void __hbird_write_stick(unsigned long val)
307 {
308 	unsigned long low = (val & 0xffffffffUL);
309 	unsigned long high = (val >> 32UL);
310 	unsigned long addr = HBIRD_STICK_ADDR;
311 
312 	__asm__ __volatile__("stxa	%%g0, [%0] %4\n\t"
313 			     "add	%0, 0x8, %0\n\t"
314 			     "stxa	%3, [%0] %4\n\t"
315 			     "sub	%0, 0x8, %0\n\t"
316 			     "stxa	%2, [%0] %4"
317 			     : "=&r" (addr)
318 			     : "0" (addr), "r" (low), "r" (high),
319 			       "i" (ASI_PHYS_BYPASS_EC_E));
320 }
321 
322 static void __hbird_write_compare(unsigned long val)
323 {
324 	unsigned long low = (val & 0xffffffffUL);
325 	unsigned long high = (val >> 32UL);
326 	unsigned long addr = HBIRD_STICKCMP_ADDR + 0x8UL;
327 
328 	__asm__ __volatile__("stxa	%3, [%0] %4\n\t"
329 			     "sub	%0, 0x8, %0\n\t"
330 			     "stxa	%2, [%0] %4"
331 			     : "=&r" (addr)
332 			     : "0" (addr), "r" (low), "r" (high),
333 			       "i" (ASI_PHYS_BYPASS_EC_E));
334 }
335 
336 static void hbtick_disable_irq(void)
337 {
338 	__hbird_write_compare(TICKCMP_IRQ_BIT);
339 }
340 
341 static void hbtick_init_tick(void)
342 {
343 	tick_disable_protection();
344 
345 	/* XXX This seems to be necessary to 'jumpstart' Hummingbird
346 	 * XXX into actually sending STICK interrupts.  I think because
347 	 * XXX of how we store %tick_cmpr in head.S this somehow resets the
348 	 * XXX {TICK + STICK} interrupt mux.  -DaveM
349 	 */
350 	__hbird_write_stick(__hbird_read_stick());
351 
352 	hbtick_disable_irq();
353 }
354 
355 static unsigned long long hbtick_get_tick(void)
356 {
357 	return __hbird_read_stick() & ~TICK_PRIV_BIT;
358 }
359 
360 static unsigned long hbtick_add_tick(unsigned long adj)
361 {
362 	unsigned long val;
363 
364 	val = __hbird_read_stick() + adj;
365 	__hbird_write_stick(val);
366 
367 	return val;
368 }
369 
370 static int hbtick_add_compare(unsigned long adj)
371 {
372 	unsigned long val = __hbird_read_stick();
373 	unsigned long val2;
374 
375 	val &= ~TICKCMP_IRQ_BIT;
376 	val += adj;
377 	__hbird_write_compare(val);
378 
379 	val2 = __hbird_read_stick() & ~TICKCMP_IRQ_BIT;
380 
381 	return ((long)(val2 - val)) > 0L;
382 }
383 
384 static struct sparc64_tick_ops hbtick_operations __read_mostly = {
385 	.name		=	"hbtick",
386 	.init_tick	=	hbtick_init_tick,
387 	.disable_irq	=	hbtick_disable_irq,
388 	.get_tick	=	hbtick_get_tick,
389 	.add_tick	=	hbtick_add_tick,
390 	.add_compare	=	hbtick_add_compare,
391 	.softint_mask	=	1UL << 0,
392 };
393 
394 static unsigned long timer_ticks_per_nsec_quotient __read_mostly;
395 
396 unsigned long cmos_regs;
397 EXPORT_SYMBOL(cmos_regs);
398 
399 static struct resource rtc_cmos_resource;
400 
401 static struct platform_device rtc_cmos_device = {
402 	.name		= "rtc_cmos",
403 	.id		= -1,
404 	.resource	= &rtc_cmos_resource,
405 	.num_resources	= 1,
406 };
407 
408 static int rtc_probe(struct platform_device *op)
409 {
410 	struct resource *r;
411 
412 	printk(KERN_INFO "%s: RTC regs at 0x%llx\n",
413 	       op->dev.of_node->full_name, op->resource[0].start);
414 
415 	/* The CMOS RTC driver only accepts IORESOURCE_IO, so cons
416 	 * up a fake resource so that the probe works for all cases.
417 	 * When the RTC is behind an ISA bus it will have IORESOURCE_IO
418 	 * already, whereas when it's behind EBUS is will be IORESOURCE_MEM.
419 	 */
420 
421 	r = &rtc_cmos_resource;
422 	r->flags = IORESOURCE_IO;
423 	r->name = op->resource[0].name;
424 	r->start = op->resource[0].start;
425 	r->end = op->resource[0].end;
426 
427 	cmos_regs = op->resource[0].start;
428 	return platform_device_register(&rtc_cmos_device);
429 }
430 
431 static const struct of_device_id rtc_match[] = {
432 	{
433 		.name = "rtc",
434 		.compatible = "m5819",
435 	},
436 	{
437 		.name = "rtc",
438 		.compatible = "isa-m5819p",
439 	},
440 	{
441 		.name = "rtc",
442 		.compatible = "isa-m5823p",
443 	},
444 	{
445 		.name = "rtc",
446 		.compatible = "ds1287",
447 	},
448 	{},
449 };
450 
451 static struct platform_driver rtc_driver = {
452 	.probe		= rtc_probe,
453 	.driver = {
454 		.name = "rtc",
455 		.of_match_table = rtc_match,
456 	},
457 };
458 
459 static struct platform_device rtc_bq4802_device = {
460 	.name		= "rtc-bq4802",
461 	.id		= -1,
462 	.num_resources	= 1,
463 };
464 
465 static int bq4802_probe(struct platform_device *op)
466 {
467 
468 	printk(KERN_INFO "%s: BQ4802 regs at 0x%llx\n",
469 	       op->dev.of_node->full_name, op->resource[0].start);
470 
471 	rtc_bq4802_device.resource = &op->resource[0];
472 	return platform_device_register(&rtc_bq4802_device);
473 }
474 
475 static const struct of_device_id bq4802_match[] = {
476 	{
477 		.name = "rtc",
478 		.compatible = "bq4802",
479 	},
480 	{},
481 };
482 
483 static struct platform_driver bq4802_driver = {
484 	.probe		= bq4802_probe,
485 	.driver = {
486 		.name = "bq4802",
487 		.of_match_table = bq4802_match,
488 	},
489 };
490 
491 static unsigned char mostek_read_byte(struct device *dev, u32 ofs)
492 {
493 	struct platform_device *pdev = to_platform_device(dev);
494 	void __iomem *regs = (void __iomem *) pdev->resource[0].start;
495 
496 	return readb(regs + ofs);
497 }
498 
499 static void mostek_write_byte(struct device *dev, u32 ofs, u8 val)
500 {
501 	struct platform_device *pdev = to_platform_device(dev);
502 	void __iomem *regs = (void __iomem *) pdev->resource[0].start;
503 
504 	writeb(val, regs + ofs);
505 }
506 
507 static struct m48t59_plat_data m48t59_data = {
508 	.read_byte	= mostek_read_byte,
509 	.write_byte	= mostek_write_byte,
510 };
511 
512 static struct platform_device m48t59_rtc = {
513 	.name		= "rtc-m48t59",
514 	.id		= 0,
515 	.num_resources	= 1,
516 	.dev	= {
517 		.platform_data = &m48t59_data,
518 	},
519 };
520 
521 static int mostek_probe(struct platform_device *op)
522 {
523 	struct device_node *dp = op->dev.of_node;
524 
525 	/* On an Enterprise system there can be multiple mostek clocks.
526 	 * We should only match the one that is on the central FHC bus.
527 	 */
528 	if (!strcmp(dp->parent->name, "fhc") &&
529 	    strcmp(dp->parent->parent->name, "central") != 0)
530 		return -ENODEV;
531 
532 	printk(KERN_INFO "%s: Mostek regs at 0x%llx\n",
533 	       dp->full_name, op->resource[0].start);
534 
535 	m48t59_rtc.resource = &op->resource[0];
536 	return platform_device_register(&m48t59_rtc);
537 }
538 
539 static const struct of_device_id mostek_match[] = {
540 	{
541 		.name = "eeprom",
542 	},
543 	{},
544 };
545 
546 static struct platform_driver mostek_driver = {
547 	.probe		= mostek_probe,
548 	.driver = {
549 		.name = "mostek",
550 		.of_match_table = mostek_match,
551 	},
552 };
553 
554 static struct platform_device rtc_sun4v_device = {
555 	.name		= "rtc-sun4v",
556 	.id		= -1,
557 };
558 
559 static struct platform_device rtc_starfire_device = {
560 	.name		= "rtc-starfire",
561 	.id		= -1,
562 };
563 
564 static int __init clock_init(void)
565 {
566 	if (this_is_starfire)
567 		return platform_device_register(&rtc_starfire_device);
568 
569 	if (tlb_type == hypervisor)
570 		return platform_device_register(&rtc_sun4v_device);
571 
572 	(void) platform_driver_register(&rtc_driver);
573 	(void) platform_driver_register(&mostek_driver);
574 	(void) platform_driver_register(&bq4802_driver);
575 
576 	return 0;
577 }
578 
579 /* Must be after subsys_initcall() so that busses are probed.  Must
580  * be before device_initcall() because things like the RTC driver
581  * need to see the clock registers.
582  */
583 fs_initcall(clock_init);
584 
585 /* This is gets the master TICK_INT timer going. */
586 static unsigned long sparc64_init_timers(void)
587 {
588 	struct device_node *dp;
589 	unsigned long freq;
590 
591 	dp = of_find_node_by_path("/");
592 	if (tlb_type == spitfire) {
593 		unsigned long ver, manuf, impl;
594 
595 		__asm__ __volatile__ ("rdpr %%ver, %0"
596 				      : "=&r" (ver));
597 		manuf = ((ver >> 48) & 0xffff);
598 		impl = ((ver >> 32) & 0xffff);
599 		if (manuf == 0x17 && impl == 0x13) {
600 			/* Hummingbird, aka Ultra-IIe */
601 			tick_ops = &hbtick_operations;
602 			freq = of_getintprop_default(dp, "stick-frequency", 0);
603 		} else {
604 			tick_ops = &tick_operations;
605 			freq = local_cpu_data().clock_tick;
606 		}
607 	} else {
608 		tick_ops = &stick_operations;
609 		freq = of_getintprop_default(dp, "stick-frequency", 0);
610 	}
611 
612 	return freq;
613 }
614 
615 struct freq_table {
616 	unsigned long clock_tick_ref;
617 	unsigned int ref_freq;
618 };
619 static DEFINE_PER_CPU(struct freq_table, sparc64_freq_table) = { 0, 0 };
620 
621 unsigned long sparc64_get_clock_tick(unsigned int cpu)
622 {
623 	struct freq_table *ft = &per_cpu(sparc64_freq_table, cpu);
624 
625 	if (ft->clock_tick_ref)
626 		return ft->clock_tick_ref;
627 	return cpu_data(cpu).clock_tick;
628 }
629 EXPORT_SYMBOL(sparc64_get_clock_tick);
630 
631 #ifdef CONFIG_CPU_FREQ
632 
633 static int sparc64_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
634 				    void *data)
635 {
636 	struct cpufreq_freqs *freq = data;
637 	unsigned int cpu = freq->cpu;
638 	struct freq_table *ft = &per_cpu(sparc64_freq_table, cpu);
639 
640 	if (!ft->ref_freq) {
641 		ft->ref_freq = freq->old;
642 		ft->clock_tick_ref = cpu_data(cpu).clock_tick;
643 	}
644 	if ((val == CPUFREQ_PRECHANGE  && freq->old < freq->new) ||
645 	    (val == CPUFREQ_POSTCHANGE && freq->old > freq->new)) {
646 		cpu_data(cpu).clock_tick =
647 			cpufreq_scale(ft->clock_tick_ref,
648 				      ft->ref_freq,
649 				      freq->new);
650 	}
651 
652 	return 0;
653 }
654 
655 static struct notifier_block sparc64_cpufreq_notifier_block = {
656 	.notifier_call	= sparc64_cpufreq_notifier
657 };
658 
659 static int __init register_sparc64_cpufreq_notifier(void)
660 {
661 
662 	cpufreq_register_notifier(&sparc64_cpufreq_notifier_block,
663 				  CPUFREQ_TRANSITION_NOTIFIER);
664 	return 0;
665 }
666 
667 core_initcall(register_sparc64_cpufreq_notifier);
668 
669 #endif /* CONFIG_CPU_FREQ */
670 
671 static int sparc64_next_event(unsigned long delta,
672 			      struct clock_event_device *evt)
673 {
674 	return tick_ops->add_compare(delta) ? -ETIME : 0;
675 }
676 
677 static int sparc64_timer_shutdown(struct clock_event_device *evt)
678 {
679 	tick_ops->disable_irq();
680 	return 0;
681 }
682 
683 static struct clock_event_device sparc64_clockevent = {
684 	.features		= CLOCK_EVT_FEAT_ONESHOT,
685 	.set_state_shutdown	= sparc64_timer_shutdown,
686 	.set_next_event		= sparc64_next_event,
687 	.rating			= 100,
688 	.shift			= 30,
689 	.irq			= -1,
690 };
691 static DEFINE_PER_CPU(struct clock_event_device, sparc64_events);
692 
693 void __irq_entry timer_interrupt(int irq, struct pt_regs *regs)
694 {
695 	struct pt_regs *old_regs = set_irq_regs(regs);
696 	unsigned long tick_mask = tick_ops->softint_mask;
697 	int cpu = smp_processor_id();
698 	struct clock_event_device *evt = &per_cpu(sparc64_events, cpu);
699 
700 	clear_softint(tick_mask);
701 
702 	irq_enter();
703 
704 	local_cpu_data().irq0_irqs++;
705 	kstat_incr_irq_this_cpu(0);
706 
707 	if (unlikely(!evt->event_handler)) {
708 		printk(KERN_WARNING
709 		       "Spurious SPARC64 timer interrupt on cpu %d\n", cpu);
710 	} else
711 		evt->event_handler(evt);
712 
713 	irq_exit();
714 
715 	set_irq_regs(old_regs);
716 }
717 
718 void setup_sparc64_timer(void)
719 {
720 	struct clock_event_device *sevt;
721 	unsigned long pstate;
722 
723 	/* Guarantee that the following sequences execute
724 	 * uninterrupted.
725 	 */
726 	__asm__ __volatile__("rdpr	%%pstate, %0\n\t"
727 			     "wrpr	%0, %1, %%pstate"
728 			     : "=r" (pstate)
729 			     : "i" (PSTATE_IE));
730 
731 	tick_ops->init_tick();
732 
733 	/* Restore PSTATE_IE. */
734 	__asm__ __volatile__("wrpr	%0, 0x0, %%pstate"
735 			     : /* no outputs */
736 			     : "r" (pstate));
737 
738 	sevt = this_cpu_ptr(&sparc64_events);
739 
740 	memcpy(sevt, &sparc64_clockevent, sizeof(*sevt));
741 	sevt->cpumask = cpumask_of(smp_processor_id());
742 
743 	clockevents_register_device(sevt);
744 }
745 
746 #define SPARC64_NSEC_PER_CYC_SHIFT	10UL
747 
748 static struct clocksource clocksource_tick = {
749 	.rating		= 100,
750 	.mask		= CLOCKSOURCE_MASK(64),
751 	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
752 };
753 
754 static unsigned long tb_ticks_per_usec __read_mostly;
755 
756 void __delay(unsigned long loops)
757 {
758 	unsigned long bclock, now;
759 
760 	bclock = tick_ops->get_tick();
761 	do {
762 		now = tick_ops->get_tick();
763 	} while ((now-bclock) < loops);
764 }
765 EXPORT_SYMBOL(__delay);
766 
767 void udelay(unsigned long usecs)
768 {
769 	__delay(tb_ticks_per_usec * usecs);
770 }
771 EXPORT_SYMBOL(udelay);
772 
773 static cycle_t clocksource_tick_read(struct clocksource *cs)
774 {
775 	return tick_ops->get_tick();
776 }
777 
778 void __init time_init(void)
779 {
780 	unsigned long freq = sparc64_init_timers();
781 
782 	tb_ticks_per_usec = freq / USEC_PER_SEC;
783 
784 	timer_ticks_per_nsec_quotient =
785 		clocksource_hz2mult(freq, SPARC64_NSEC_PER_CYC_SHIFT);
786 
787 	clocksource_tick.name = tick_ops->name;
788 	clocksource_tick.read = clocksource_tick_read;
789 
790 	clocksource_register_hz(&clocksource_tick, freq);
791 	printk("clocksource: mult[%x] shift[%d]\n",
792 	       clocksource_tick.mult, clocksource_tick.shift);
793 
794 	sparc64_clockevent.name = tick_ops->name;
795 	clockevents_calc_mult_shift(&sparc64_clockevent, freq, 4);
796 
797 	sparc64_clockevent.max_delta_ns =
798 		clockevent_delta2ns(0x7fffffffffffffffUL, &sparc64_clockevent);
799 	sparc64_clockevent.min_delta_ns =
800 		clockevent_delta2ns(0xF, &sparc64_clockevent);
801 
802 	printk("clockevent: mult[%x] shift[%d]\n",
803 	       sparc64_clockevent.mult, sparc64_clockevent.shift);
804 
805 	setup_sparc64_timer();
806 }
807 
808 unsigned long long sched_clock(void)
809 {
810 	unsigned long ticks = tick_ops->get_tick();
811 
812 	return (ticks * timer_ticks_per_nsec_quotient)
813 		>> SPARC64_NSEC_PER_CYC_SHIFT;
814 }
815 
816 int read_current_timer(unsigned long *timer_val)
817 {
818 	*timer_val = tick_ops->get_tick();
819 	return 0;
820 }
821