summaryrefslogtreecommitdiff
path: root/arch/sparc/kernel/time_64.c
blob: 3b397081047af69a23b6672917e1706786d3134f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
// SPDX-License-Identifier: GPL-2.0
/* time.c: UltraSparc timer and TOD clock support.
 *
 * Copyright (C) 1997, 2008 David S. Miller (davem@davemloft.net)
 * Copyright (C) 1998 Eddie C. Dost   (ecd@skynet.be)
 *
 * Based largely on code which is:
 *
 * Copyright (C) 1996 Thomas K. Dyas (tdyas@eden.rutgers.edu)
 */

#include <linux/errno.h>
#include <linux/export.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/param.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/time.h>
#include <linux/timex.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/mc146818rtc.h>
#include <linux/delay.h>
#include <linux/profile.h>
#include <linux/bcd.h>
#include <linux/jiffies.h>
#include <linux/cpufreq.h>
#include <linux/percpu.h>
#include <linux/miscdevice.h>
#include <linux/rtc/m48t59.h>
#include <linux/kernel_stat.h>
#include <linux/clockchips.h>
#include <linux/clocksource.h>
#include <linux/platform_device.h>
#include <linux/ftrace.h>

#include <asm/oplib.h>
#include <asm/timer.h>
#include <asm/irq.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/starfire.h>
#include <asm/smp.h>
#include <asm/sections.h>
#include <asm/cpudata.h>
#include <linux/uaccess.h>
#include <asm/irq_regs.h>
#include <asm/cacheflush.h>

#include "entry.h"
#include "kernel.h"

DEFINE_SPINLOCK(rtc_lock);

#ifdef CONFIG_SMP
unsigned long profile_pc(struct pt_regs *regs)
{
	unsigned long pc = instruction_pointer(regs);

	if (in_lock_functions(pc))
		return regs->u_regs[UREG_RETPC];
	return pc;
}
EXPORT_SYMBOL(profile_pc);
#endif

static void tick_disable_protection(void)
{
	/* Set things up so user can access tick register for profiling
	 * purposes.  Also workaround BB_ERRATA_1 by doing a dummy
	 * read back of %tick after writing it.
	 */
	__asm__ __volatile__(
	"	ba,pt	%%xcc, 1f\n"
	"	 nop\n"
	"	.align	64\n"
	"1:	rd	%%tick, %%g2\n"
	"	add	%%g2, 6, %%g2\n"
	"	andn	%%g2, %0, %%g2\n"
	"	wrpr	%%g2, 0, %%tick\n"
	"	rdpr	%%tick, %%g0"
	: /* no outputs */
	: "r" (TICK_PRIV_BIT)
	: "g2");
}

static void tick_disable_irq(void)
{
	__asm__ __volatile__(
	"	ba,pt	%%xcc, 1f\n"
	"	 nop\n"
	"	.align	64\n"
	"1:	wr	%0, 0x0, %%tick_cmpr\n"
	"	rd	%%tick_cmpr, %%g0"
	: /* no outputs */
	: "r" (TICKCMP_IRQ_BIT));
}

static void tick_init_tick(void)
{
	tick_disable_protection();
	tick_disable_irq();
}

static unsigned long long tick_get_tick(void)
{
	unsigned long ret;

	__asm__ __volatile__("rd	%%tick, %0\n\t"
			     "mov	%0, %0"
			     : "=r" (ret));

	return ret & ~TICK_PRIV_BIT;
}

static int tick_add_compare(unsigned long adj)
{
	unsigned long orig_tick, new_tick, new_compare;

	__asm__ __volatile__("rd	%%tick, %0"
			     : "=r" (orig_tick));

	orig_tick &= ~TICKCMP_IRQ_BIT;

	/* Workaround for Spitfire Errata (#54 I think??), I discovered
	 * this via Sun BugID 4008234, mentioned in Solaris-2.5.1 patch
	 * number 103640.
	 *
	 * On Blackbird writes to %tick_cmpr can fail, the
	 * workaround seems to be to execute the wr instruction
	 * at the start of an I-cache line, and perform a dummy
	 * read back from %tick_cmpr right after writing to it. -DaveM
	 */
	__asm__ __volatile__("ba,pt	%%xcc, 1f\n\t"
			     " add	%1, %2, %0\n\t"
			     ".align	64\n"
			     "1:\n\t"
			     "wr	%0, 0, %%tick_cmpr\n\t"
			     "rd	%%tick_cmpr, %%g0\n\t"
			     : "=r" (new_compare)
			     : "r" (orig_tick), "r" (adj));

	__asm__ __volatile__("rd	%%tick, %0"
			     : "=r" (new_tick));
	new_tick &= ~TICKCMP_IRQ_BIT;

	return ((long)(new_tick - (orig_tick+adj))) > 0L;
}

static unsigned long tick_add_tick(unsigned long adj)
{
	unsigned long new_tick;

	/* Also need to handle Blackbird bug here too. */
	__asm__ __volatile__("rd	%%tick, %0\n\t"
			     "add	%0, %1, %0\n\t"
			     "wrpr	%0, 0, %%tick\n\t"
			     : "=&r" (new_tick)
			     : "r" (adj));

	return new_tick;
}

/* Searches for cpu clock frequency with given cpuid in OpenBoot tree */
static unsigned long cpuid_to_freq(phandle node, int cpuid)
{
	bool is_cpu_node = false;
	unsigned long freq = 0;
	char type[128];

	if (!node)
		return freq;

	if (prom_getproperty(node, "device_type", type, sizeof(type)) != -1)
		is_cpu_node = (strcmp(type, "cpu") == 0);

	/* try upa-portid then cpuid to get cpuid, see prom_64.c */
	if (is_cpu_node && (prom_getint(node, "upa-portid") == cpuid ||
			    prom_getint(node, "cpuid") == cpuid))
		freq = prom_getintdefault(node, "clock-frequency", 0);
	if (!freq)
		freq = cpuid_to_freq(prom_getchild(node), cpuid);
	if (!freq)
		freq = cpuid_to_freq(prom_getsibling(node), cpuid);

	return freq;
}

static unsigned long tick_get_frequency(void)
{
	return cpuid_to_freq(prom_root_node, hard_smp_processor_id());
}

static struct sparc64_tick_ops tick_operations __cacheline_aligned = {
	.name		=	"tick",
	.init_tick	=	tick_init_tick,
	.disable_irq	=	tick_disable_irq,
	.get_tick	=	tick_get_tick,
	.add_tick	=	tick_add_tick,
	.add_compare	=	tick_add_compare,
	.get_frequency	=	tick_get_frequency,
	.softint_mask	=	1UL << 0,
};

struct sparc64_tick_ops *tick_ops __read_mostly = &tick_operations;
EXPORT_SYMBOL(tick_ops);

static void stick_disable_irq(void)
{
	__asm__ __volatile__(
	"wr	%0, 0x0, %%asr25"
	: /* no outputs */
	: "r" (TICKCMP_IRQ_BIT));
}

static void stick_init_tick(void)
{
	/* Writes to the %tick and %stick register are not
	 * allowed on sun4v.  The Hypervisor controls that
	 * bit, per-strand.
	 */
	if (tlb_type != hypervisor) {
		tick_disable_protection();
		tick_disable_irq();

		/* Let the user get at STICK too. */
		__asm__ __volatile__(
		"	rd	%%asr24, %%g2\n"
		"	andn	%%g2, %0, %%g2\n"
		"	wr	%%g2, 0, %%asr24"
		: /* no outputs */
		: "r" (TICK_PRIV_BIT)
		: "g1", "g2");
	}

	stick_disable_irq();
}

static unsigned long long stick_get_tick(void)
{
	unsigned long ret;

	__asm__ __volatile__("rd	%%asr24, %0"
			     : "=r" (ret));

	return ret & ~TICK_PRIV_BIT;
}

static unsigned long stick_add_tick(unsigned long adj)
{
	unsigned long new_tick;

	__asm__ __volatile__("rd	%%asr24, %0\n\t"
			     "add	%0, %1, %0\n\t"
			     "wr	%0, 0, %%asr24\n\t"
			     : "=&r" (new_tick)
			     : "r" (adj));

	return new_tick;
}

static int stick_add_compare(unsigned long adj)
{
	unsigned long orig_tick, new_tick;

	__asm__ __volatile__("rd	%%asr24, %0"
			     : "=r" (orig_tick));
	orig_tick &= ~TICKCMP_IRQ_BIT;

	__asm__ __volatile__("wr	%0, 0, %%asr25"
			     : /* no outputs */
			     : "r" (orig_tick + adj));

	__asm__ __volatile__("rd	%%asr24, %0"
			     : "=r" (new_tick));
	new_tick &= ~TICKCMP_IRQ_BIT;

	return ((long)(new_tick - (orig_tick+adj))) > 0L;
}

static unsigned long stick_get_frequency(void)
{
	return prom_getintdefault(prom_root_node, "stick-frequency", 0);
}

static struct sparc64_tick_ops stick_operations __read_mostly = {
	.name		=	"stick",
	.init_tick	=	stick_init_tick,
	.disable_irq	=	stick_disable_irq,
	.get_tick	=	stick_get_tick,
	.add_tick	=	stick_add_tick,
	.add_compare	=	stick_add_compare,
	.get_frequency	=	stick_get_frequency,
	.softint_mask	=	1UL << 16,
};

/* On Hummingbird the STICK/STICK_CMPR register is implemented
 * in I/O space.  There are two 64-bit registers each, the
 * first holds the low 32-bits of the value and the second holds
 * the high 32-bits.
 *
 * Since STICK is constantly updating, we have to access it carefully.
 *
 * The sequence we use to read is:
 * 1) read high
 * 2) read low
 * 3) read high again, if it rolled re-read both low and high again.
 *
 * Writing STICK safely is also tricky:
 * 1) write low to zero
 * 2) write high
 * 3) write low
 */
static unsigned long __hbird_read_stick(void)
{
	unsigned long ret, tmp1, tmp2, tmp3;
	unsigned long addr = HBIRD_STICK_ADDR+8;

	__asm__ __volatile__("ldxa	[%1] %5, %2\n"
			     "1:\n\t"
			     "sub	%1, 0x8, %1\n\t"
			     "ldxa	[%1] %5, %3\n\t"
			     "add	%1, 0x8, %1\n\t"
			     "ldxa	[%1] %5, %4\n\t"
			     "cmp	%4, %2\n\t"
			     "bne,a,pn	%%xcc, 1b\n\t"
			     " mov	%4, %2\n\t"
			     "sllx	%4, 32, %4\n\t"
			     "or	%3, %4, %0\n\t"
			     : "=&r" (ret), "=&r" (addr),
			       "=&r" (tmp1), "=&r" (tmp2), "=&r" (tmp3)
			     : "i" (ASI_PHYS_BYPASS_EC_E), "1" (addr));

	return ret;
}

static void __hbird_write_stick(unsigned long val)
{
	unsigned long low = (val & 0xffffffffUL);
	unsigned long high = (val >> 32UL);
	unsigned long addr = HBIRD_STICK_ADDR;

	__asm__ __volatile__("stxa	%%g0, [%0] %4\n\t"
			     "add	%0, 0x8, %0\n\t"
			     "stxa	%3, [%0] %4\n\t"
			     "sub	%0, 0x8, %0\n\t"
			     "stxa	%2, [%0] %4"
			     : "=&r" (addr)
			     : "0" (addr), "r" (low), "r" (high),
			       "i" (ASI_PHYS_BYPASS_EC_E));
}

static void __hbird_write_compare(unsigned long val)
{
	unsigned long low = (val & 0xffffffffUL);
	unsigned long high = (val >> 32UL);
	unsigned long addr = HBIRD_STICKCMP_ADDR + 0x8UL;

	__asm__ __volatile__("stxa	%3, [%0] %4\n\t"
			     "sub	%0, 0x8, %0\n\t"
			     "stxa	%2, [%0] %4"
			     : "=&r" (addr)
			     : "0" (addr), "r" (low), "r" (high),
			       "i" (ASI_PHYS_BYPASS_EC_E));
}

static void hbtick_disable_irq(void)
{
	__hbird_write_compare(TICKCMP_IRQ_BIT);
}

static void hbtick_init_tick(void)
{
	tick_disable_protection();

	/* XXX This seems to be necessary to 'jumpstart' Hummingbird
	 * XXX into actually sending STICK interrupts.  I think because
	 * XXX of how we store %tick_cmpr in head.S this somehow resets the
	 * XXX {TICK + STICK} interrupt mux.  -DaveM
	 */
	__hbird_write_stick(__hbird_read_stick());

	hbtick_disable_irq();
}

static unsigned long long hbtick_get_tick(void)
{
	return __hbird_read_stick() & ~TICK_PRIV_BIT;
}

static unsigned long hbtick_add_tick(unsigned long adj)
{
	unsigned long val;

	val = __hbird_read_stick() + adj;
	__hbird_write_stick(val);

	return val;
}

static int hbtick_add_compare(unsigned long adj)
{
	unsigned long val = __hbird_read_stick();
	unsigned long val2;

	val &= ~TICKCMP_IRQ_BIT;
	val += adj;
	__hbird_write_compare(val);

	val2 = __hbird_read_stick() & ~TICKCMP_IRQ_BIT;

	return ((long)(val2 - val)) > 0L;
}

static unsigned long hbtick_get_frequency(void)
{
	return prom_getintdefault(prom_root_node, "stick-frequency", 0);
}

static struct sparc64_tick_ops hbtick_operations __read_mostly = {
	.name		=	"hbtick",
	.init_tick	=	hbtick_init_tick,
	.disable_irq	=	hbtick_disable_irq,
	.get_tick	=	hbtick_get_tick,
	.add_tick	=	hbtick_add_tick,
	.add_compare	=	hbtick_add_compare,
	.get_frequency	=	hbtick_get_frequency,
	.softint_mask	=	1UL << 0,
};

unsigned long cmos_regs;
EXPORT_SYMBOL(cmos_regs);

static struct resource rtc_cmos_resource;

static struct platform_device rtc_cmos_device = {
	.name		= "rtc_cmos",
	.id		= -1,
	.resource	= &rtc_cmos_resource,
	.num_resources	= 1,
};

static int rtc_probe(struct platform_device *op)
{
	struct resource *r;

	printk(KERN_INFO "%s: RTC regs at 0x%llx\n",
	       op->dev.of_node->full_name, op->resource[0].start);

	/* The CMOS RTC driver only accepts IORESOURCE_IO, so cons
	 * up a fake resource so that the probe works for all cases.
	 * When the RTC is behind an ISA bus it will have IORESOURCE_IO
	 * already, whereas when it's behind EBUS is will be IORESOURCE_MEM.
	 */

	r = &rtc_cmos_resource;
	r->flags = IORESOURCE_IO;
	r->name = op->resource[0].name;
	r->start = op->resource[0].start;
	r->end = op->resource[0].end;

	cmos_regs = op->resource[0].start;
	return platform_device_register(&rtc_cmos_device);
}

static const struct of_device_id rtc_match[] = {
	{
		.name = "rtc",
		.compatible = "m5819",
	},
	{
		.name = "rtc",
		.compatible = "isa-m5819p",
	},
	{
		.name = "rtc",
		.compatible = "isa-m5823p",
	},
	{
		.name = "rtc",
		.compatible = "ds1287",
	},
	{},
};

static struct platform_driver rtc_driver = {
	.probe		= rtc_probe,
	.driver = {
		.name = "rtc",
		.of_match_table = rtc_match,
	},
};

static struct platform_device rtc_bq4802_device = {
	.name		= "rtc-bq4802",
	.id		= -1,
	.num_resources	= 1,
};

static int bq4802_probe(struct platform_device *op)
{

	printk(KERN_INFO "%s: BQ4802 regs at 0x%llx\n",
	       op->dev.of_node->full_name, op->resource[0].start);

	rtc_bq4802_device.resource = &op->resource[0];
	return platform_device_register(&rtc_bq4802_device);
}

static const struct of_device_id bq4802_match[] = {
	{
		.name = "rtc",
		.compatible = "bq4802",
	},
	{},
};

static struct platform_driver bq4802_driver = {
	.probe		= bq4802_probe,
	.driver = {
		.name = "bq4802",
		.of_match_table = bq4802_match,
	},
};

static unsigned char mostek_read_byte(struct device *dev, u32 ofs)
{
	struct platform_device *pdev = to_platform_device(dev);
	void __iomem *regs = (void __iomem *) pdev->resource[0].start;

	return readb(regs + ofs);
}

static void mostek_write_byte(struct device *dev, u32 ofs, u8 val)
{
	struct platform_device *pdev = to_platform_device(dev);
	void __iomem *regs = (void __iomem *) pdev->resource[0].start;

	writeb(val, regs + ofs);
}

static struct m48t59_plat_data m48t59_data = {
	.read_byte	= mostek_read_byte,
	.write_byte	= mostek_write_byte,
};

static struct platform_device m48t59_rtc = {
	.name		= "rtc-m48t59",
	.id		= 0,
	.num_resources	= 1,
	.dev	= {
		.platform_data = &m48t59_data,
	},
};

static int mostek_probe(struct platform_device *op)
{
	struct device_node *dp = op->dev.of_node;

	/* On an Enterprise system there can be multiple mostek clocks.
	 * We should only match the one that is on the central FHC bus.
	 */
	if (!strcmp(dp->parent->name, "fhc") &&
	    strcmp(dp->parent->parent->name, "central") != 0)
		return -ENODEV;

	printk(KERN_INFO "%s: Mostek regs at 0x%llx\n",
	       dp->full_name, op->resource[0].start);

	m48t59_rtc.resource = &op->resource[0];
	return platform_device_register(&m48t59_rtc);
}

static const struct of_device_id mostek_match[] = {
	{
		.name = "eeprom",
	},
	{},
};

static struct platform_driver mostek_driver = {
	.probe		= mostek_probe,
	.driver = {
		.name = "mostek",
		.of_match_table = mostek_match,
	},
};

static struct platform_device rtc_sun4v_device = {
	.name		= "rtc-sun4v",
	.id		= -1,
};

static struct platform_device rtc_starfire_device = {
	.name		= "rtc-starfire",
	.id		= -1,
};

static int __init clock_init(void)
{
	if (this_is_starfire)
		return platform_device_register(&rtc_starfire_device);

	if (tlb_type == hypervisor)
		return platform_device_register(&rtc_sun4v_device);

	(void) platform_driver_register(&rtc_driver);
	(void) platform_driver_register(&mostek_driver);
	(void) platform_driver_register(&bq4802_driver);

	return 0;
}

/* Must be after subsys_initcall() so that busses are probed.  Must
 * be before device_initcall() because things like the RTC driver
 * need to see the clock registers.
 */
fs_initcall(clock_init);

/* Return true if this is Hummingbird, aka Ultra-IIe */
static bool is_hummingbird(void)
{
	unsigned long ver, manuf, impl;

	__asm__ __volatile__ ("rdpr %%ver, %0"
			      : "=&r" (ver));
	manuf = ((ver >> 48) & 0xffff);
	impl = ((ver >> 32) & 0xffff);

	return (manuf == 0x17 && impl == 0x13);
}

struct freq_table {
	unsigned long clock_tick_ref;
	unsigned int ref_freq;
};
static DEFINE_PER_CPU(struct freq_table, sparc64_freq_table) = { 0, 0 };

unsigned long sparc64_get_clock_tick(unsigned int cpu)
{
	struct freq_table *ft = &per_cpu(sparc64_freq_table, cpu);

	if (ft->clock_tick_ref)
		return ft->clock_tick_ref;
	return cpu_data(cpu).clock_tick;
}
EXPORT_SYMBOL(sparc64_get_clock_tick);

#ifdef CONFIG_CPU_FREQ

static int sparc64_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
				    void *data)
{
	struct cpufreq_freqs *freq = data;
	unsigned int cpu = freq->cpu;
	struct freq_table *ft = &per_cpu(sparc64_freq_table, cpu);

	if (!ft->ref_freq) {
		ft->ref_freq = freq->old;
		ft->clock_tick_ref = cpu_data(cpu).clock_tick;
	}
	if ((val == CPUFREQ_PRECHANGE  && freq->old < freq->new) ||
	    (val == CPUFREQ_POSTCHANGE && freq->old > freq->new)) {
		cpu_data(cpu).clock_tick =
			cpufreq_scale(ft->clock_tick_ref,
				      ft->ref_freq,
				      freq->new);
	}

	return 0;
}

static struct notifier_block sparc64_cpufreq_notifier_block = {
	.notifier_call	= sparc64_cpufreq_notifier
};

static int __init register_sparc64_cpufreq_notifier(void)
{

	cpufreq_register_notifier(&sparc64_cpufreq_notifier_block,
				  CPUFREQ_TRANSITION_NOTIFIER);
	return 0;
}

core_initcall(register_sparc64_cpufreq_notifier);

#endif /* CONFIG_CPU_FREQ */

static int sparc64_next_event(unsigned long delta,
			      struct clock_event_device *evt)
{
	return tick_operations.add_compare(delta) ? -ETIME : 0;
}

static int sparc64_timer_shutdown(struct clock_event_device *evt)
{
	tick_operations.disable_irq();
	return 0;
}

static struct clock_event_device sparc64_clockevent = {
	.features		= CLOCK_EVT_FEAT_ONESHOT,
	.set_state_shutdown	= sparc64_timer_shutdown,
	.set_next_event		= sparc64_next_event,
	.rating			= 100,
	.shift			= 30,
	.irq			= -1,
};
static DEFINE_PER_CPU(struct clock_event_device, sparc64_events);

void __irq_entry timer_interrupt(int irq, struct pt_regs *regs)
{
	struct pt_regs *old_regs = set_irq_regs(regs);
	unsigned long tick_mask = tick_operations.softint_mask;
	int cpu = smp_processor_id();
	struct clock_event_device *evt = &per_cpu(sparc64_events, cpu);

	clear_softint(tick_mask);

	irq_enter();

	local_cpu_data().irq0_irqs++;
	kstat_incr_irq_this_cpu(0);

	if (unlikely(!evt->event_handler)) {
		printk(KERN_WARNING
		       "Spurious SPARC64 timer interrupt on cpu %d\n", cpu);
	} else
		evt->event_handler(evt);

	irq_exit();

	set_irq_regs(old_regs);
}

void setup_sparc64_timer(void)
{
	struct clock_event_device *sevt;
	unsigned long pstate;

	/* Guarantee that the following sequences execute
	 * uninterrupted.
	 */
	__asm__ __volatile__("rdpr	%%pstate, %0\n\t"
			     "wrpr	%0, %1, %%pstate"
			     : "=r" (pstate)
			     : "i" (PSTATE_IE));

	tick_operations.init_tick();

	/* Restore PSTATE_IE. */
	__asm__ __volatile__("wrpr	%0, 0x0, %%pstate"
			     : /* no outputs */
			     : "r" (pstate));

	sevt = this_cpu_ptr(&sparc64_events);

	memcpy(sevt, &sparc64_clockevent, sizeof(*sevt));
	sevt->cpumask = cpumask_of(smp_processor_id());

	clockevents_register_device(sevt);
}

#define SPARC64_NSEC_PER_CYC_SHIFT	10UL

static struct clocksource clocksource_tick = {
	.rating		= 100,
	.mask		= CLOCKSOURCE_MASK(64),
	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
};

static unsigned long tb_ticks_per_usec __read_mostly;

void __delay(unsigned long loops)
{
	unsigned long bclock = get_tick();

	while ((get_tick() - bclock) < loops)
		;
}
EXPORT_SYMBOL(__delay);

void udelay(unsigned long usecs)
{
	__delay(tb_ticks_per_usec * usecs);
}
EXPORT_SYMBOL(udelay);

static u64 clocksource_tick_read(struct clocksource *cs)
{
	return get_tick();
}

static void __init get_tick_patch(void)
{
	unsigned int *addr, *instr, i;
	struct get_tick_patch *p;

	if (tlb_type == spitfire && is_hummingbird())
		return;

	for (p = &__get_tick_patch; p < &__get_tick_patch_end; p++) {
		instr = (tlb_type == spitfire) ? p->tick : p->stick;
		addr = (unsigned int *)(unsigned long)p->addr;
		for (i = 0; i < GET_TICK_NINSTR; i++) {
			addr[i] = instr[i];
			/* ensure that address is modified before flush */
			wmb();
			flushi(&addr[i]);
		}
	}
}

static void init_tick_ops(struct sparc64_tick_ops *ops)
{
	unsigned long freq, quotient, tick;

	freq = ops->get_frequency();
	quotient = clocksource_hz2mult(freq, SPARC64_NSEC_PER_CYC_SHIFT);
	tick = ops->get_tick();

	ops->offset = (tick * quotient) >> SPARC64_NSEC_PER_CYC_SHIFT;
	ops->ticks_per_nsec_quotient = quotient;
	ops->frequency = freq;
	tick_operations = *ops;
	get_tick_patch();
}

void __init time_init_early(void)
{
	if (tlb_type == spitfire) {
		if (is_hummingbird())
			init_tick_ops(&hbtick_operations);
		else
			init_tick_ops(&tick_operations);
	} else {
		init_tick_ops(&stick_operations);
	}
}

void __init time_init(void)
{
	unsigned long freq;

	freq = tick_operations.frequency;
	tb_ticks_per_usec = freq / USEC_PER_SEC;

	clocksource_tick.name = tick_operations.name;
	clocksource_tick.read = clocksource_tick_read;

	clocksource_register_hz(&clocksource_tick, freq);
	printk("clocksource: mult[%x] shift[%d]\n",
	       clocksource_tick.mult, clocksource_tick.shift);

	sparc64_clockevent.name = tick_operations.name;
	clockevents_calc_mult_shift(&sparc64_clockevent, freq, 4);

	sparc64_clockevent.max_delta_ns =
		clockevent_delta2ns(0x7fffffffffffffffUL, &sparc64_clockevent);
	sparc64_clockevent.max_delta_ticks = 0x7fffffffffffffffUL;
	sparc64_clockevent.min_delta_ns =
		clockevent_delta2ns(0xF, &sparc64_clockevent);
	sparc64_clockevent.min_delta_ticks = 0xF;

	printk("clockevent: mult[%x] shift[%d]\n",
	       sparc64_clockevent.mult, sparc64_clockevent.shift);

	setup_sparc64_timer();
}

unsigned long long sched_clock(void)
{
	unsigned long quotient = tick_operations.ticks_per_nsec_quotient;
	unsigned long offset = tick_operations.offset;

	/* Use barrier so the compiler emits the loads first and overlaps load
	 * latency with reading tick, because reading %tick/%stick is a
	 * post-sync instruction that will flush and restart subsequent
	 * instructions after it commits.
	 */
	barrier();

	return ((get_tick() * quotient) >> SPARC64_NSEC_PER_CYC_SHIFT) - offset;
}

int read_current_timer(unsigned long *timer_val)
{
	*timer_val = get_tick();
	return 0;
}