xref: /openbmc/linux/arch/sparc/kernel/time_64.c (revision 78c99ba1)
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/module.h>
13 #include <linux/sched.h>
14 #include <linux/smp_lock.h>
15 #include <linux/kernel.h>
16 #include <linux/param.h>
17 #include <linux/string.h>
18 #include <linux/mm.h>
19 #include <linux/interrupt.h>
20 #include <linux/time.h>
21 #include <linux/timex.h>
22 #include <linux/init.h>
23 #include <linux/ioport.h>
24 #include <linux/mc146818rtc.h>
25 #include <linux/delay.h>
26 #include <linux/profile.h>
27 #include <linux/bcd.h>
28 #include <linux/jiffies.h>
29 #include <linux/cpufreq.h>
30 #include <linux/percpu.h>
31 #include <linux/miscdevice.h>
32 #include <linux/rtc.h>
33 #include <linux/rtc/m48t59.h>
34 #include <linux/kernel_stat.h>
35 #include <linux/clockchips.h>
36 #include <linux/clocksource.h>
37 #include <linux/of_device.h>
38 #include <linux/platform_device.h>
39 
40 #include <asm/oplib.h>
41 #include <asm/timer.h>
42 #include <asm/irq.h>
43 #include <asm/io.h>
44 #include <asm/prom.h>
45 #include <asm/starfire.h>
46 #include <asm/smp.h>
47 #include <asm/sections.h>
48 #include <asm/cpudata.h>
49 #include <asm/uaccess.h>
50 #include <asm/irq_regs.h>
51 
52 #include "entry.h"
53 
54 DEFINE_SPINLOCK(rtc_lock);
55 
56 #define TICK_PRIV_BIT	(1UL << 63)
57 #define TICKCMP_IRQ_BIT	(1UL << 63)
58 
59 #ifdef CONFIG_SMP
60 unsigned long profile_pc(struct pt_regs *regs)
61 {
62 	unsigned long pc = instruction_pointer(regs);
63 
64 	if (in_lock_functions(pc))
65 		return regs->u_regs[UREG_RETPC];
66 	return pc;
67 }
68 EXPORT_SYMBOL(profile_pc);
69 #endif
70 
71 static void tick_disable_protection(void)
72 {
73 	/* Set things up so user can access tick register for profiling
74 	 * purposes.  Also workaround BB_ERRATA_1 by doing a dummy
75 	 * read back of %tick after writing it.
76 	 */
77 	__asm__ __volatile__(
78 	"	ba,pt	%%xcc, 1f\n"
79 	"	 nop\n"
80 	"	.align	64\n"
81 	"1:	rd	%%tick, %%g2\n"
82 	"	add	%%g2, 6, %%g2\n"
83 	"	andn	%%g2, %0, %%g2\n"
84 	"	wrpr	%%g2, 0, %%tick\n"
85 	"	rdpr	%%tick, %%g0"
86 	: /* no outputs */
87 	: "r" (TICK_PRIV_BIT)
88 	: "g2");
89 }
90 
91 static void tick_disable_irq(void)
92 {
93 	__asm__ __volatile__(
94 	"	ba,pt	%%xcc, 1f\n"
95 	"	 nop\n"
96 	"	.align	64\n"
97 	"1:	wr	%0, 0x0, %%tick_cmpr\n"
98 	"	rd	%%tick_cmpr, %%g0"
99 	: /* no outputs */
100 	: "r" (TICKCMP_IRQ_BIT));
101 }
102 
103 static void tick_init_tick(void)
104 {
105 	tick_disable_protection();
106 	tick_disable_irq();
107 }
108 
109 static unsigned long long tick_get_tick(void)
110 {
111 	unsigned long ret;
112 
113 	__asm__ __volatile__("rd	%%tick, %0\n\t"
114 			     "mov	%0, %0"
115 			     : "=r" (ret));
116 
117 	return ret & ~TICK_PRIV_BIT;
118 }
119 
120 static int tick_add_compare(unsigned long adj)
121 {
122 	unsigned long orig_tick, new_tick, new_compare;
123 
124 	__asm__ __volatile__("rd	%%tick, %0"
125 			     : "=r" (orig_tick));
126 
127 	orig_tick &= ~TICKCMP_IRQ_BIT;
128 
129 	/* Workaround for Spitfire Errata (#54 I think??), I discovered
130 	 * this via Sun BugID 4008234, mentioned in Solaris-2.5.1 patch
131 	 * number 103640.
132 	 *
133 	 * On Blackbird writes to %tick_cmpr can fail, the
134 	 * workaround seems to be to execute the wr instruction
135 	 * at the start of an I-cache line, and perform a dummy
136 	 * read back from %tick_cmpr right after writing to it. -DaveM
137 	 */
138 	__asm__ __volatile__("ba,pt	%%xcc, 1f\n\t"
139 			     " add	%1, %2, %0\n\t"
140 			     ".align	64\n"
141 			     "1:\n\t"
142 			     "wr	%0, 0, %%tick_cmpr\n\t"
143 			     "rd	%%tick_cmpr, %%g0\n\t"
144 			     : "=r" (new_compare)
145 			     : "r" (orig_tick), "r" (adj));
146 
147 	__asm__ __volatile__("rd	%%tick, %0"
148 			     : "=r" (new_tick));
149 	new_tick &= ~TICKCMP_IRQ_BIT;
150 
151 	return ((long)(new_tick - (orig_tick+adj))) > 0L;
152 }
153 
154 static unsigned long tick_add_tick(unsigned long adj)
155 {
156 	unsigned long new_tick;
157 
158 	/* Also need to handle Blackbird bug here too. */
159 	__asm__ __volatile__("rd	%%tick, %0\n\t"
160 			     "add	%0, %1, %0\n\t"
161 			     "wrpr	%0, 0, %%tick\n\t"
162 			     : "=&r" (new_tick)
163 			     : "r" (adj));
164 
165 	return new_tick;
166 }
167 
168 static struct sparc64_tick_ops tick_operations __read_mostly = {
169 	.name		=	"tick",
170 	.init_tick	=	tick_init_tick,
171 	.disable_irq	=	tick_disable_irq,
172 	.get_tick	=	tick_get_tick,
173 	.add_tick	=	tick_add_tick,
174 	.add_compare	=	tick_add_compare,
175 	.softint_mask	=	1UL << 0,
176 };
177 
178 struct sparc64_tick_ops *tick_ops __read_mostly = &tick_operations;
179 EXPORT_SYMBOL(tick_ops);
180 
181 static void stick_disable_irq(void)
182 {
183 	__asm__ __volatile__(
184 	"wr	%0, 0x0, %%asr25"
185 	: /* no outputs */
186 	: "r" (TICKCMP_IRQ_BIT));
187 }
188 
189 static void stick_init_tick(void)
190 {
191 	/* Writes to the %tick and %stick register are not
192 	 * allowed on sun4v.  The Hypervisor controls that
193 	 * bit, per-strand.
194 	 */
195 	if (tlb_type != hypervisor) {
196 		tick_disable_protection();
197 		tick_disable_irq();
198 
199 		/* Let the user get at STICK too. */
200 		__asm__ __volatile__(
201 		"	rd	%%asr24, %%g2\n"
202 		"	andn	%%g2, %0, %%g2\n"
203 		"	wr	%%g2, 0, %%asr24"
204 		: /* no outputs */
205 		: "r" (TICK_PRIV_BIT)
206 		: "g1", "g2");
207 	}
208 
209 	stick_disable_irq();
210 }
211 
212 static unsigned long long stick_get_tick(void)
213 {
214 	unsigned long ret;
215 
216 	__asm__ __volatile__("rd	%%asr24, %0"
217 			     : "=r" (ret));
218 
219 	return ret & ~TICK_PRIV_BIT;
220 }
221 
222 static unsigned long stick_add_tick(unsigned long adj)
223 {
224 	unsigned long new_tick;
225 
226 	__asm__ __volatile__("rd	%%asr24, %0\n\t"
227 			     "add	%0, %1, %0\n\t"
228 			     "wr	%0, 0, %%asr24\n\t"
229 			     : "=&r" (new_tick)
230 			     : "r" (adj));
231 
232 	return new_tick;
233 }
234 
235 static int stick_add_compare(unsigned long adj)
236 {
237 	unsigned long orig_tick, new_tick;
238 
239 	__asm__ __volatile__("rd	%%asr24, %0"
240 			     : "=r" (orig_tick));
241 	orig_tick &= ~TICKCMP_IRQ_BIT;
242 
243 	__asm__ __volatile__("wr	%0, 0, %%asr25"
244 			     : /* no outputs */
245 			     : "r" (orig_tick + adj));
246 
247 	__asm__ __volatile__("rd	%%asr24, %0"
248 			     : "=r" (new_tick));
249 	new_tick &= ~TICKCMP_IRQ_BIT;
250 
251 	return ((long)(new_tick - (orig_tick+adj))) > 0L;
252 }
253 
254 static struct sparc64_tick_ops stick_operations __read_mostly = {
255 	.name		=	"stick",
256 	.init_tick	=	stick_init_tick,
257 	.disable_irq	=	stick_disable_irq,
258 	.get_tick	=	stick_get_tick,
259 	.add_tick	=	stick_add_tick,
260 	.add_compare	=	stick_add_compare,
261 	.softint_mask	=	1UL << 16,
262 };
263 
264 /* On Hummingbird the STICK/STICK_CMPR register is implemented
265  * in I/O space.  There are two 64-bit registers each, the
266  * first holds the low 32-bits of the value and the second holds
267  * the high 32-bits.
268  *
269  * Since STICK is constantly updating, we have to access it carefully.
270  *
271  * The sequence we use to read is:
272  * 1) read high
273  * 2) read low
274  * 3) read high again, if it rolled re-read both low and high again.
275  *
276  * Writing STICK safely is also tricky:
277  * 1) write low to zero
278  * 2) write high
279  * 3) write low
280  */
281 #define HBIRD_STICKCMP_ADDR	0x1fe0000f060UL
282 #define HBIRD_STICK_ADDR	0x1fe0000f070UL
283 
284 static unsigned long __hbird_read_stick(void)
285 {
286 	unsigned long ret, tmp1, tmp2, tmp3;
287 	unsigned long addr = HBIRD_STICK_ADDR+8;
288 
289 	__asm__ __volatile__("ldxa	[%1] %5, %2\n"
290 			     "1:\n\t"
291 			     "sub	%1, 0x8, %1\n\t"
292 			     "ldxa	[%1] %5, %3\n\t"
293 			     "add	%1, 0x8, %1\n\t"
294 			     "ldxa	[%1] %5, %4\n\t"
295 			     "cmp	%4, %2\n\t"
296 			     "bne,a,pn	%%xcc, 1b\n\t"
297 			     " mov	%4, %2\n\t"
298 			     "sllx	%4, 32, %4\n\t"
299 			     "or	%3, %4, %0\n\t"
300 			     : "=&r" (ret), "=&r" (addr),
301 			       "=&r" (tmp1), "=&r" (tmp2), "=&r" (tmp3)
302 			     : "i" (ASI_PHYS_BYPASS_EC_E), "1" (addr));
303 
304 	return ret;
305 }
306 
307 static void __hbird_write_stick(unsigned long val)
308 {
309 	unsigned long low = (val & 0xffffffffUL);
310 	unsigned long high = (val >> 32UL);
311 	unsigned long addr = HBIRD_STICK_ADDR;
312 
313 	__asm__ __volatile__("stxa	%%g0, [%0] %4\n\t"
314 			     "add	%0, 0x8, %0\n\t"
315 			     "stxa	%3, [%0] %4\n\t"
316 			     "sub	%0, 0x8, %0\n\t"
317 			     "stxa	%2, [%0] %4"
318 			     : "=&r" (addr)
319 			     : "0" (addr), "r" (low), "r" (high),
320 			       "i" (ASI_PHYS_BYPASS_EC_E));
321 }
322 
323 static void __hbird_write_compare(unsigned long val)
324 {
325 	unsigned long low = (val & 0xffffffffUL);
326 	unsigned long high = (val >> 32UL);
327 	unsigned long addr = HBIRD_STICKCMP_ADDR + 0x8UL;
328 
329 	__asm__ __volatile__("stxa	%3, [%0] %4\n\t"
330 			     "sub	%0, 0x8, %0\n\t"
331 			     "stxa	%2, [%0] %4"
332 			     : "=&r" (addr)
333 			     : "0" (addr), "r" (low), "r" (high),
334 			       "i" (ASI_PHYS_BYPASS_EC_E));
335 }
336 
337 static void hbtick_disable_irq(void)
338 {
339 	__hbird_write_compare(TICKCMP_IRQ_BIT);
340 }
341 
342 static void hbtick_init_tick(void)
343 {
344 	tick_disable_protection();
345 
346 	/* XXX This seems to be necessary to 'jumpstart' Hummingbird
347 	 * XXX into actually sending STICK interrupts.  I think because
348 	 * XXX of how we store %tick_cmpr in head.S this somehow resets the
349 	 * XXX {TICK + STICK} interrupt mux.  -DaveM
350 	 */
351 	__hbird_write_stick(__hbird_read_stick());
352 
353 	hbtick_disable_irq();
354 }
355 
356 static unsigned long long hbtick_get_tick(void)
357 {
358 	return __hbird_read_stick() & ~TICK_PRIV_BIT;
359 }
360 
361 static unsigned long hbtick_add_tick(unsigned long adj)
362 {
363 	unsigned long val;
364 
365 	val = __hbird_read_stick() + adj;
366 	__hbird_write_stick(val);
367 
368 	return val;
369 }
370 
371 static int hbtick_add_compare(unsigned long adj)
372 {
373 	unsigned long val = __hbird_read_stick();
374 	unsigned long val2;
375 
376 	val &= ~TICKCMP_IRQ_BIT;
377 	val += adj;
378 	__hbird_write_compare(val);
379 
380 	val2 = __hbird_read_stick() & ~TICKCMP_IRQ_BIT;
381 
382 	return ((long)(val2 - val)) > 0L;
383 }
384 
385 static struct sparc64_tick_ops hbtick_operations __read_mostly = {
386 	.name		=	"hbtick",
387 	.init_tick	=	hbtick_init_tick,
388 	.disable_irq	=	hbtick_disable_irq,
389 	.get_tick	=	hbtick_get_tick,
390 	.add_tick	=	hbtick_add_tick,
391 	.add_compare	=	hbtick_add_compare,
392 	.softint_mask	=	1UL << 0,
393 };
394 
395 static unsigned long timer_ticks_per_nsec_quotient __read_mostly;
396 
397 int update_persistent_clock(struct timespec now)
398 {
399 	struct rtc_device *rtc = rtc_class_open("rtc0");
400 	int err = -1;
401 
402 	if (rtc) {
403 		err = rtc_set_mmss(rtc, now.tv_sec);
404 		rtc_class_close(rtc);
405 	}
406 
407 	return err;
408 }
409 
410 unsigned long cmos_regs;
411 EXPORT_SYMBOL(cmos_regs);
412 
413 static struct resource rtc_cmos_resource;
414 
415 static struct platform_device rtc_cmos_device = {
416 	.name		= "rtc_cmos",
417 	.id		= -1,
418 	.resource	= &rtc_cmos_resource,
419 	.num_resources	= 1,
420 };
421 
422 static int __devinit rtc_probe(struct of_device *op, const struct of_device_id *match)
423 {
424 	struct resource *r;
425 
426 	printk(KERN_INFO "%s: RTC regs at 0x%llx\n",
427 	       op->node->full_name, op->resource[0].start);
428 
429 	/* The CMOS RTC driver only accepts IORESOURCE_IO, so cons
430 	 * up a fake resource so that the probe works for all cases.
431 	 * When the RTC is behind an ISA bus it will have IORESOURCE_IO
432 	 * already, whereas when it's behind EBUS is will be IORESOURCE_MEM.
433 	 */
434 
435 	r = &rtc_cmos_resource;
436 	r->flags = IORESOURCE_IO;
437 	r->name = op->resource[0].name;
438 	r->start = op->resource[0].start;
439 	r->end = op->resource[0].end;
440 
441 	cmos_regs = op->resource[0].start;
442 	return platform_device_register(&rtc_cmos_device);
443 }
444 
445 static struct of_device_id __initdata rtc_match[] = {
446 	{
447 		.name = "rtc",
448 		.compatible = "m5819",
449 	},
450 	{
451 		.name = "rtc",
452 		.compatible = "isa-m5819p",
453 	},
454 	{
455 		.name = "rtc",
456 		.compatible = "isa-m5823p",
457 	},
458 	{
459 		.name = "rtc",
460 		.compatible = "ds1287",
461 	},
462 	{},
463 };
464 
465 static struct of_platform_driver rtc_driver = {
466 	.match_table	= rtc_match,
467 	.probe		= rtc_probe,
468 	.driver		= {
469 		.name	= "rtc",
470 	},
471 };
472 
473 static struct platform_device rtc_bq4802_device = {
474 	.name		= "rtc-bq4802",
475 	.id		= -1,
476 	.num_resources	= 1,
477 };
478 
479 static int __devinit bq4802_probe(struct of_device *op, const struct of_device_id *match)
480 {
481 
482 	printk(KERN_INFO "%s: BQ4802 regs at 0x%llx\n",
483 	       op->node->full_name, op->resource[0].start);
484 
485 	rtc_bq4802_device.resource = &op->resource[0];
486 	return platform_device_register(&rtc_bq4802_device);
487 }
488 
489 static struct of_device_id __initdata bq4802_match[] = {
490 	{
491 		.name = "rtc",
492 		.compatible = "bq4802",
493 	},
494 	{},
495 };
496 
497 static struct of_platform_driver bq4802_driver = {
498 	.match_table	= bq4802_match,
499 	.probe		= bq4802_probe,
500 	.driver		= {
501 		.name	= "bq4802",
502 	},
503 };
504 
505 static unsigned char mostek_read_byte(struct device *dev, u32 ofs)
506 {
507 	struct platform_device *pdev = to_platform_device(dev);
508 	void __iomem *regs = (void __iomem *) pdev->resource[0].start;
509 
510 	return readb(regs + ofs);
511 }
512 
513 static void mostek_write_byte(struct device *dev, u32 ofs, u8 val)
514 {
515 	struct platform_device *pdev = to_platform_device(dev);
516 	void __iomem *regs = (void __iomem *) pdev->resource[0].start;
517 
518 	writeb(val, regs + ofs);
519 }
520 
521 static struct m48t59_plat_data m48t59_data = {
522 	.read_byte	= mostek_read_byte,
523 	.write_byte	= mostek_write_byte,
524 };
525 
526 static struct platform_device m48t59_rtc = {
527 	.name		= "rtc-m48t59",
528 	.id		= 0,
529 	.num_resources	= 1,
530 	.dev	= {
531 		.platform_data = &m48t59_data,
532 	},
533 };
534 
535 static int __devinit mostek_probe(struct of_device *op, const struct of_device_id *match)
536 {
537 	struct device_node *dp = op->node;
538 
539 	/* On an Enterprise system there can be multiple mostek clocks.
540 	 * We should only match the one that is on the central FHC bus.
541 	 */
542 	if (!strcmp(dp->parent->name, "fhc") &&
543 	    strcmp(dp->parent->parent->name, "central") != 0)
544 		return -ENODEV;
545 
546 	printk(KERN_INFO "%s: Mostek regs at 0x%llx\n",
547 	       dp->full_name, op->resource[0].start);
548 
549 	m48t59_rtc.resource = &op->resource[0];
550 	return platform_device_register(&m48t59_rtc);
551 }
552 
553 static struct of_device_id __initdata mostek_match[] = {
554 	{
555 		.name = "eeprom",
556 	},
557 	{},
558 };
559 
560 static struct of_platform_driver mostek_driver = {
561 	.match_table	= mostek_match,
562 	.probe		= mostek_probe,
563 	.driver		= {
564 		.name	= "mostek",
565 	},
566 };
567 
568 static struct platform_device rtc_sun4v_device = {
569 	.name		= "rtc-sun4v",
570 	.id		= -1,
571 };
572 
573 static struct platform_device rtc_starfire_device = {
574 	.name		= "rtc-starfire",
575 	.id		= -1,
576 };
577 
578 static int __init clock_init(void)
579 {
580 	if (this_is_starfire)
581 		return platform_device_register(&rtc_starfire_device);
582 
583 	if (tlb_type == hypervisor)
584 		return platform_device_register(&rtc_sun4v_device);
585 
586 	(void) of_register_driver(&rtc_driver, &of_platform_bus_type);
587 	(void) of_register_driver(&mostek_driver, &of_platform_bus_type);
588 	(void) of_register_driver(&bq4802_driver, &of_platform_bus_type);
589 
590 	return 0;
591 }
592 
593 /* Must be after subsys_initcall() so that busses are probed.  Must
594  * be before device_initcall() because things like the RTC driver
595  * need to see the clock registers.
596  */
597 fs_initcall(clock_init);
598 
599 /* This is gets the master TICK_INT timer going. */
600 static unsigned long sparc64_init_timers(void)
601 {
602 	struct device_node *dp;
603 	unsigned long freq;
604 
605 	dp = of_find_node_by_path("/");
606 	if (tlb_type == spitfire) {
607 		unsigned long ver, manuf, impl;
608 
609 		__asm__ __volatile__ ("rdpr %%ver, %0"
610 				      : "=&r" (ver));
611 		manuf = ((ver >> 48) & 0xffff);
612 		impl = ((ver >> 32) & 0xffff);
613 		if (manuf == 0x17 && impl == 0x13) {
614 			/* Hummingbird, aka Ultra-IIe */
615 			tick_ops = &hbtick_operations;
616 			freq = of_getintprop_default(dp, "stick-frequency", 0);
617 		} else {
618 			tick_ops = &tick_operations;
619 			freq = local_cpu_data().clock_tick;
620 		}
621 	} else {
622 		tick_ops = &stick_operations;
623 		freq = of_getintprop_default(dp, "stick-frequency", 0);
624 	}
625 
626 	return freq;
627 }
628 
629 struct freq_table {
630 	unsigned long clock_tick_ref;
631 	unsigned int ref_freq;
632 };
633 static DEFINE_PER_CPU(struct freq_table, sparc64_freq_table) = { 0, 0 };
634 
635 unsigned long sparc64_get_clock_tick(unsigned int cpu)
636 {
637 	struct freq_table *ft = &per_cpu(sparc64_freq_table, cpu);
638 
639 	if (ft->clock_tick_ref)
640 		return ft->clock_tick_ref;
641 	return cpu_data(cpu).clock_tick;
642 }
643 EXPORT_SYMBOL(sparc64_get_clock_tick);
644 
645 #ifdef CONFIG_CPU_FREQ
646 
647 static int sparc64_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
648 				    void *data)
649 {
650 	struct cpufreq_freqs *freq = data;
651 	unsigned int cpu = freq->cpu;
652 	struct freq_table *ft = &per_cpu(sparc64_freq_table, cpu);
653 
654 	if (!ft->ref_freq) {
655 		ft->ref_freq = freq->old;
656 		ft->clock_tick_ref = cpu_data(cpu).clock_tick;
657 	}
658 	if ((val == CPUFREQ_PRECHANGE  && freq->old < freq->new) ||
659 	    (val == CPUFREQ_POSTCHANGE && freq->old > freq->new) ||
660 	    (val == CPUFREQ_RESUMECHANGE)) {
661 		cpu_data(cpu).clock_tick =
662 			cpufreq_scale(ft->clock_tick_ref,
663 				      ft->ref_freq,
664 				      freq->new);
665 	}
666 
667 	return 0;
668 }
669 
670 static struct notifier_block sparc64_cpufreq_notifier_block = {
671 	.notifier_call	= sparc64_cpufreq_notifier
672 };
673 
674 static int __init register_sparc64_cpufreq_notifier(void)
675 {
676 
677 	cpufreq_register_notifier(&sparc64_cpufreq_notifier_block,
678 				  CPUFREQ_TRANSITION_NOTIFIER);
679 	return 0;
680 }
681 
682 core_initcall(register_sparc64_cpufreq_notifier);
683 
684 #endif /* CONFIG_CPU_FREQ */
685 
686 static int sparc64_next_event(unsigned long delta,
687 			      struct clock_event_device *evt)
688 {
689 	return tick_ops->add_compare(delta) ? -ETIME : 0;
690 }
691 
692 static void sparc64_timer_setup(enum clock_event_mode mode,
693 				struct clock_event_device *evt)
694 {
695 	switch (mode) {
696 	case CLOCK_EVT_MODE_ONESHOT:
697 	case CLOCK_EVT_MODE_RESUME:
698 		break;
699 
700 	case CLOCK_EVT_MODE_SHUTDOWN:
701 		tick_ops->disable_irq();
702 		break;
703 
704 	case CLOCK_EVT_MODE_PERIODIC:
705 	case CLOCK_EVT_MODE_UNUSED:
706 		WARN_ON(1);
707 		break;
708 	};
709 }
710 
711 static struct clock_event_device sparc64_clockevent = {
712 	.features	= CLOCK_EVT_FEAT_ONESHOT,
713 	.set_mode	= sparc64_timer_setup,
714 	.set_next_event	= sparc64_next_event,
715 	.rating		= 100,
716 	.shift		= 30,
717 	.irq		= -1,
718 };
719 static DEFINE_PER_CPU(struct clock_event_device, sparc64_events);
720 
721 void timer_interrupt(int irq, struct pt_regs *regs)
722 {
723 	struct pt_regs *old_regs = set_irq_regs(regs);
724 	unsigned long tick_mask = tick_ops->softint_mask;
725 	int cpu = smp_processor_id();
726 	struct clock_event_device *evt = &per_cpu(sparc64_events, cpu);
727 
728 	clear_softint(tick_mask);
729 
730 	irq_enter();
731 
732 	kstat_incr_irqs_this_cpu(0, irq_to_desc(0));
733 
734 	if (unlikely(!evt->event_handler)) {
735 		printk(KERN_WARNING
736 		       "Spurious SPARC64 timer interrupt on cpu %d\n", cpu);
737 	} else
738 		evt->event_handler(evt);
739 
740 	irq_exit();
741 
742 	set_irq_regs(old_regs);
743 }
744 
745 void __devinit setup_sparc64_timer(void)
746 {
747 	struct clock_event_device *sevt;
748 	unsigned long pstate;
749 
750 	/* Guarantee that the following sequences execute
751 	 * uninterrupted.
752 	 */
753 	__asm__ __volatile__("rdpr	%%pstate, %0\n\t"
754 			     "wrpr	%0, %1, %%pstate"
755 			     : "=r" (pstate)
756 			     : "i" (PSTATE_IE));
757 
758 	tick_ops->init_tick();
759 
760 	/* Restore PSTATE_IE. */
761 	__asm__ __volatile__("wrpr	%0, 0x0, %%pstate"
762 			     : /* no outputs */
763 			     : "r" (pstate));
764 
765 	sevt = &__get_cpu_var(sparc64_events);
766 
767 	memcpy(sevt, &sparc64_clockevent, sizeof(*sevt));
768 	sevt->cpumask = cpumask_of(smp_processor_id());
769 
770 	clockevents_register_device(sevt);
771 }
772 
773 #define SPARC64_NSEC_PER_CYC_SHIFT	10UL
774 
775 static struct clocksource clocksource_tick = {
776 	.rating		= 100,
777 	.mask		= CLOCKSOURCE_MASK(64),
778 	.shift		= 16,
779 	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
780 };
781 
782 static void __init setup_clockevent_multiplier(unsigned long hz)
783 {
784 	unsigned long mult, shift = 32;
785 
786 	while (1) {
787 		mult = div_sc(hz, NSEC_PER_SEC, shift);
788 		if (mult && (mult >> 32UL) == 0UL)
789 			break;
790 
791 		shift--;
792 	}
793 
794 	sparc64_clockevent.shift = shift;
795 	sparc64_clockevent.mult = mult;
796 }
797 
798 static unsigned long tb_ticks_per_usec __read_mostly;
799 
800 void __delay(unsigned long loops)
801 {
802 	unsigned long bclock, now;
803 
804 	bclock = tick_ops->get_tick();
805 	do {
806 		now = tick_ops->get_tick();
807 	} while ((now-bclock) < loops);
808 }
809 EXPORT_SYMBOL(__delay);
810 
811 void udelay(unsigned long usecs)
812 {
813 	__delay(tb_ticks_per_usec * usecs);
814 }
815 EXPORT_SYMBOL(udelay);
816 
817 static cycle_t clocksource_tick_read(struct clocksource *cs)
818 {
819 	return tick_ops->get_tick();
820 }
821 
822 void __init time_init(void)
823 {
824 	unsigned long freq = sparc64_init_timers();
825 
826 	tb_ticks_per_usec = freq / USEC_PER_SEC;
827 
828 	timer_ticks_per_nsec_quotient =
829 		clocksource_hz2mult(freq, SPARC64_NSEC_PER_CYC_SHIFT);
830 
831 	clocksource_tick.name = tick_ops->name;
832 	clocksource_tick.mult =
833 		clocksource_hz2mult(freq,
834 				    clocksource_tick.shift);
835 	clocksource_tick.read = clocksource_tick_read;
836 
837 	printk("clocksource: mult[%x] shift[%d]\n",
838 	       clocksource_tick.mult, clocksource_tick.shift);
839 
840 	clocksource_register(&clocksource_tick);
841 
842 	sparc64_clockevent.name = tick_ops->name;
843 
844 	setup_clockevent_multiplier(freq);
845 
846 	sparc64_clockevent.max_delta_ns =
847 		clockevent_delta2ns(0x7fffffffffffffffUL, &sparc64_clockevent);
848 	sparc64_clockevent.min_delta_ns =
849 		clockevent_delta2ns(0xF, &sparc64_clockevent);
850 
851 	printk("clockevent: mult[%lx] shift[%d]\n",
852 	       sparc64_clockevent.mult, sparc64_clockevent.shift);
853 
854 	setup_sparc64_timer();
855 }
856 
857 unsigned long long sched_clock(void)
858 {
859 	unsigned long ticks = tick_ops->get_tick();
860 
861 	return (ticks * timer_ticks_per_nsec_quotient)
862 		>> SPARC64_NSEC_PER_CYC_SHIFT;
863 }
864 
865 int __devinit read_current_timer(unsigned long *timer_val)
866 {
867 	*timer_val = tick_ops->get_tick();
868 	return 0;
869 }
870