Merge tag 'linux-watchdog-4.20-rc1' of git://www.linux-watchdog.org/linux-watchdog
[sfrench/cifs-2.6.git] / arch / sparc / kernel / time_64.c
1 // SPDX-License-Identifier: GPL-2.0
2 /* time.c: UltraSparc timer and TOD clock support.
3  *
4  * Copyright (C) 1997, 2008 David S. Miller (davem@davemloft.net)
5  * Copyright (C) 1998 Eddie C. Dost   (ecd@skynet.be)
6  *
7  * Based largely on code which is:
8  *
9  * Copyright (C) 1996 Thomas K. Dyas (tdyas@eden.rutgers.edu)
10  */
11
12 #include <linux/errno.h>
13 #include <linux/export.h>
14 #include <linux/sched.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/rtc/m48t59.h>
32 #include <linux/kernel_stat.h>
33 #include <linux/clockchips.h>
34 #include <linux/clocksource.h>
35 #include <linux/platform_device.h>
36 #include <linux/ftrace.h>
37
38 #include <asm/oplib.h>
39 #include <asm/timer.h>
40 #include <asm/irq.h>
41 #include <asm/io.h>
42 #include <asm/prom.h>
43 #include <asm/starfire.h>
44 #include <asm/smp.h>
45 #include <asm/sections.h>
46 #include <asm/cpudata.h>
47 #include <linux/uaccess.h>
48 #include <asm/irq_regs.h>
49 #include <asm/cacheflush.h>
50
51 #include "entry.h"
52 #include "kernel.h"
53
54 DEFINE_SPINLOCK(rtc_lock);
55
56 #ifdef CONFIG_SMP
57 unsigned long profile_pc(struct pt_regs *regs)
58 {
59         unsigned long pc = instruction_pointer(regs);
60
61         if (in_lock_functions(pc))
62                 return regs->u_regs[UREG_RETPC];
63         return pc;
64 }
65 EXPORT_SYMBOL(profile_pc);
66 #endif
67
68 static void tick_disable_protection(void)
69 {
70         /* Set things up so user can access tick register for profiling
71          * purposes.  Also workaround BB_ERRATA_1 by doing a dummy
72          * read back of %tick after writing it.
73          */
74         __asm__ __volatile__(
75         "       ba,pt   %%xcc, 1f\n"
76         "        nop\n"
77         "       .align  64\n"
78         "1:     rd      %%tick, %%g2\n"
79         "       add     %%g2, 6, %%g2\n"
80         "       andn    %%g2, %0, %%g2\n"
81         "       wrpr    %%g2, 0, %%tick\n"
82         "       rdpr    %%tick, %%g0"
83         : /* no outputs */
84         : "r" (TICK_PRIV_BIT)
85         : "g2");
86 }
87
88 static void tick_disable_irq(void)
89 {
90         __asm__ __volatile__(
91         "       ba,pt   %%xcc, 1f\n"
92         "        nop\n"
93         "       .align  64\n"
94         "1:     wr      %0, 0x0, %%tick_cmpr\n"
95         "       rd      %%tick_cmpr, %%g0"
96         : /* no outputs */
97         : "r" (TICKCMP_IRQ_BIT));
98 }
99
100 static void tick_init_tick(void)
101 {
102         tick_disable_protection();
103         tick_disable_irq();
104 }
105
106 static unsigned long long tick_get_tick(void)
107 {
108         unsigned long ret;
109
110         __asm__ __volatile__("rd        %%tick, %0\n\t"
111                              "mov       %0, %0"
112                              : "=r" (ret));
113
114         return ret & ~TICK_PRIV_BIT;
115 }
116
117 static int tick_add_compare(unsigned long adj)
118 {
119         unsigned long orig_tick, new_tick, new_compare;
120
121         __asm__ __volatile__("rd        %%tick, %0"
122                              : "=r" (orig_tick));
123
124         orig_tick &= ~TICKCMP_IRQ_BIT;
125
126         /* Workaround for Spitfire Errata (#54 I think??), I discovered
127          * this via Sun BugID 4008234, mentioned in Solaris-2.5.1 patch
128          * number 103640.
129          *
130          * On Blackbird writes to %tick_cmpr can fail, the
131          * workaround seems to be to execute the wr instruction
132          * at the start of an I-cache line, and perform a dummy
133          * read back from %tick_cmpr right after writing to it. -DaveM
134          */
135         __asm__ __volatile__("ba,pt     %%xcc, 1f\n\t"
136                              " add      %1, %2, %0\n\t"
137                              ".align    64\n"
138                              "1:\n\t"
139                              "wr        %0, 0, %%tick_cmpr\n\t"
140                              "rd        %%tick_cmpr, %%g0\n\t"
141                              : "=r" (new_compare)
142                              : "r" (orig_tick), "r" (adj));
143
144         __asm__ __volatile__("rd        %%tick, %0"
145                              : "=r" (new_tick));
146         new_tick &= ~TICKCMP_IRQ_BIT;
147
148         return ((long)(new_tick - (orig_tick+adj))) > 0L;
149 }
150
151 static unsigned long tick_add_tick(unsigned long adj)
152 {
153         unsigned long new_tick;
154
155         /* Also need to handle Blackbird bug here too. */
156         __asm__ __volatile__("rd        %%tick, %0\n\t"
157                              "add       %0, %1, %0\n\t"
158                              "wrpr      %0, 0, %%tick\n\t"
159                              : "=&r" (new_tick)
160                              : "r" (adj));
161
162         return new_tick;
163 }
164
165 /* Searches for cpu clock frequency with given cpuid in OpenBoot tree */
166 static unsigned long cpuid_to_freq(phandle node, int cpuid)
167 {
168         bool is_cpu_node = false;
169         unsigned long freq = 0;
170         char type[128];
171
172         if (!node)
173                 return freq;
174
175         if (prom_getproperty(node, "device_type", type, sizeof(type)) != -1)
176                 is_cpu_node = (strcmp(type, "cpu") == 0);
177
178         /* try upa-portid then cpuid to get cpuid, see prom_64.c */
179         if (is_cpu_node && (prom_getint(node, "upa-portid") == cpuid ||
180                             prom_getint(node, "cpuid") == cpuid))
181                 freq = prom_getintdefault(node, "clock-frequency", 0);
182         if (!freq)
183                 freq = cpuid_to_freq(prom_getchild(node), cpuid);
184         if (!freq)
185                 freq = cpuid_to_freq(prom_getsibling(node), cpuid);
186
187         return freq;
188 }
189
190 static unsigned long tick_get_frequency(void)
191 {
192         return cpuid_to_freq(prom_root_node, hard_smp_processor_id());
193 }
194
195 static struct sparc64_tick_ops tick_operations __cacheline_aligned = {
196         .name           =       "tick",
197         .init_tick      =       tick_init_tick,
198         .disable_irq    =       tick_disable_irq,
199         .get_tick       =       tick_get_tick,
200         .add_tick       =       tick_add_tick,
201         .add_compare    =       tick_add_compare,
202         .get_frequency  =       tick_get_frequency,
203         .softint_mask   =       1UL << 0,
204 };
205
206 struct sparc64_tick_ops *tick_ops __read_mostly = &tick_operations;
207 EXPORT_SYMBOL(tick_ops);
208
209 static void stick_disable_irq(void)
210 {
211         __asm__ __volatile__(
212         "wr     %0, 0x0, %%asr25"
213         : /* no outputs */
214         : "r" (TICKCMP_IRQ_BIT));
215 }
216
217 static void stick_init_tick(void)
218 {
219         /* Writes to the %tick and %stick register are not
220          * allowed on sun4v.  The Hypervisor controls that
221          * bit, per-strand.
222          */
223         if (tlb_type != hypervisor) {
224                 tick_disable_protection();
225                 tick_disable_irq();
226
227                 /* Let the user get at STICK too. */
228                 __asm__ __volatile__(
229                 "       rd      %%asr24, %%g2\n"
230                 "       andn    %%g2, %0, %%g2\n"
231                 "       wr      %%g2, 0, %%asr24"
232                 : /* no outputs */
233                 : "r" (TICK_PRIV_BIT)
234                 : "g1", "g2");
235         }
236
237         stick_disable_irq();
238 }
239
240 static unsigned long long stick_get_tick(void)
241 {
242         unsigned long ret;
243
244         __asm__ __volatile__("rd        %%asr24, %0"
245                              : "=r" (ret));
246
247         return ret & ~TICK_PRIV_BIT;
248 }
249
250 static unsigned long stick_add_tick(unsigned long adj)
251 {
252         unsigned long new_tick;
253
254         __asm__ __volatile__("rd        %%asr24, %0\n\t"
255                              "add       %0, %1, %0\n\t"
256                              "wr        %0, 0, %%asr24\n\t"
257                              : "=&r" (new_tick)
258                              : "r" (adj));
259
260         return new_tick;
261 }
262
263 static int stick_add_compare(unsigned long adj)
264 {
265         unsigned long orig_tick, new_tick;
266
267         __asm__ __volatile__("rd        %%asr24, %0"
268                              : "=r" (orig_tick));
269         orig_tick &= ~TICKCMP_IRQ_BIT;
270
271         __asm__ __volatile__("wr        %0, 0, %%asr25"
272                              : /* no outputs */
273                              : "r" (orig_tick + adj));
274
275         __asm__ __volatile__("rd        %%asr24, %0"
276                              : "=r" (new_tick));
277         new_tick &= ~TICKCMP_IRQ_BIT;
278
279         return ((long)(new_tick - (orig_tick+adj))) > 0L;
280 }
281
282 static unsigned long stick_get_frequency(void)
283 {
284         return prom_getintdefault(prom_root_node, "stick-frequency", 0);
285 }
286
287 static struct sparc64_tick_ops stick_operations __read_mostly = {
288         .name           =       "stick",
289         .init_tick      =       stick_init_tick,
290         .disable_irq    =       stick_disable_irq,
291         .get_tick       =       stick_get_tick,
292         .add_tick       =       stick_add_tick,
293         .add_compare    =       stick_add_compare,
294         .get_frequency  =       stick_get_frequency,
295         .softint_mask   =       1UL << 16,
296 };
297
298 /* On Hummingbird the STICK/STICK_CMPR register is implemented
299  * in I/O space.  There are two 64-bit registers each, the
300  * first holds the low 32-bits of the value and the second holds
301  * the high 32-bits.
302  *
303  * Since STICK is constantly updating, we have to access it carefully.
304  *
305  * The sequence we use to read is:
306  * 1) read high
307  * 2) read low
308  * 3) read high again, if it rolled re-read both low and high again.
309  *
310  * Writing STICK safely is also tricky:
311  * 1) write low to zero
312  * 2) write high
313  * 3) write low
314  */
315 static unsigned long __hbird_read_stick(void)
316 {
317         unsigned long ret, tmp1, tmp2, tmp3;
318         unsigned long addr = HBIRD_STICK_ADDR+8;
319
320         __asm__ __volatile__("ldxa      [%1] %5, %2\n"
321                              "1:\n\t"
322                              "sub       %1, 0x8, %1\n\t"
323                              "ldxa      [%1] %5, %3\n\t"
324                              "add       %1, 0x8, %1\n\t"
325                              "ldxa      [%1] %5, %4\n\t"
326                              "cmp       %4, %2\n\t"
327                              "bne,a,pn  %%xcc, 1b\n\t"
328                              " mov      %4, %2\n\t"
329                              "sllx      %4, 32, %4\n\t"
330                              "or        %3, %4, %0\n\t"
331                              : "=&r" (ret), "=&r" (addr),
332                                "=&r" (tmp1), "=&r" (tmp2), "=&r" (tmp3)
333                              : "i" (ASI_PHYS_BYPASS_EC_E), "1" (addr));
334
335         return ret;
336 }
337
338 static void __hbird_write_stick(unsigned long val)
339 {
340         unsigned long low = (val & 0xffffffffUL);
341         unsigned long high = (val >> 32UL);
342         unsigned long addr = HBIRD_STICK_ADDR;
343
344         __asm__ __volatile__("stxa      %%g0, [%0] %4\n\t"
345                              "add       %0, 0x8, %0\n\t"
346                              "stxa      %3, [%0] %4\n\t"
347                              "sub       %0, 0x8, %0\n\t"
348                              "stxa      %2, [%0] %4"
349                              : "=&r" (addr)
350                              : "0" (addr), "r" (low), "r" (high),
351                                "i" (ASI_PHYS_BYPASS_EC_E));
352 }
353
354 static void __hbird_write_compare(unsigned long val)
355 {
356         unsigned long low = (val & 0xffffffffUL);
357         unsigned long high = (val >> 32UL);
358         unsigned long addr = HBIRD_STICKCMP_ADDR + 0x8UL;
359
360         __asm__ __volatile__("stxa      %3, [%0] %4\n\t"
361                              "sub       %0, 0x8, %0\n\t"
362                              "stxa      %2, [%0] %4"
363                              : "=&r" (addr)
364                              : "0" (addr), "r" (low), "r" (high),
365                                "i" (ASI_PHYS_BYPASS_EC_E));
366 }
367
368 static void hbtick_disable_irq(void)
369 {
370         __hbird_write_compare(TICKCMP_IRQ_BIT);
371 }
372
373 static void hbtick_init_tick(void)
374 {
375         tick_disable_protection();
376
377         /* XXX This seems to be necessary to 'jumpstart' Hummingbird
378          * XXX into actually sending STICK interrupts.  I think because
379          * XXX of how we store %tick_cmpr in head.S this somehow resets the
380          * XXX {TICK + STICK} interrupt mux.  -DaveM
381          */
382         __hbird_write_stick(__hbird_read_stick());
383
384         hbtick_disable_irq();
385 }
386
387 static unsigned long long hbtick_get_tick(void)
388 {
389         return __hbird_read_stick() & ~TICK_PRIV_BIT;
390 }
391
392 static unsigned long hbtick_add_tick(unsigned long adj)
393 {
394         unsigned long val;
395
396         val = __hbird_read_stick() + adj;
397         __hbird_write_stick(val);
398
399         return val;
400 }
401
402 static int hbtick_add_compare(unsigned long adj)
403 {
404         unsigned long val = __hbird_read_stick();
405         unsigned long val2;
406
407         val &= ~TICKCMP_IRQ_BIT;
408         val += adj;
409         __hbird_write_compare(val);
410
411         val2 = __hbird_read_stick() & ~TICKCMP_IRQ_BIT;
412
413         return ((long)(val2 - val)) > 0L;
414 }
415
416 static unsigned long hbtick_get_frequency(void)
417 {
418         return prom_getintdefault(prom_root_node, "stick-frequency", 0);
419 }
420
421 static struct sparc64_tick_ops hbtick_operations __read_mostly = {
422         .name           =       "hbtick",
423         .init_tick      =       hbtick_init_tick,
424         .disable_irq    =       hbtick_disable_irq,
425         .get_tick       =       hbtick_get_tick,
426         .add_tick       =       hbtick_add_tick,
427         .add_compare    =       hbtick_add_compare,
428         .get_frequency  =       hbtick_get_frequency,
429         .softint_mask   =       1UL << 0,
430 };
431
432 unsigned long cmos_regs;
433 EXPORT_SYMBOL(cmos_regs);
434
435 static struct resource rtc_cmos_resource;
436
437 static struct platform_device rtc_cmos_device = {
438         .name           = "rtc_cmos",
439         .id             = -1,
440         .resource       = &rtc_cmos_resource,
441         .num_resources  = 1,
442 };
443
444 static int rtc_probe(struct platform_device *op)
445 {
446         struct resource *r;
447
448         printk(KERN_INFO "%s: RTC regs at 0x%llx\n",
449                op->dev.of_node->full_name, op->resource[0].start);
450
451         /* The CMOS RTC driver only accepts IORESOURCE_IO, so cons
452          * up a fake resource so that the probe works for all cases.
453          * When the RTC is behind an ISA bus it will have IORESOURCE_IO
454          * already, whereas when it's behind EBUS is will be IORESOURCE_MEM.
455          */
456
457         r = &rtc_cmos_resource;
458         r->flags = IORESOURCE_IO;
459         r->name = op->resource[0].name;
460         r->start = op->resource[0].start;
461         r->end = op->resource[0].end;
462
463         cmos_regs = op->resource[0].start;
464         return platform_device_register(&rtc_cmos_device);
465 }
466
467 static const struct of_device_id rtc_match[] = {
468         {
469                 .name = "rtc",
470                 .compatible = "m5819",
471         },
472         {
473                 .name = "rtc",
474                 .compatible = "isa-m5819p",
475         },
476         {
477                 .name = "rtc",
478                 .compatible = "isa-m5823p",
479         },
480         {
481                 .name = "rtc",
482                 .compatible = "ds1287",
483         },
484         {},
485 };
486
487 static struct platform_driver rtc_driver = {
488         .probe          = rtc_probe,
489         .driver = {
490                 .name = "rtc",
491                 .of_match_table = rtc_match,
492         },
493 };
494
495 static struct platform_device rtc_bq4802_device = {
496         .name           = "rtc-bq4802",
497         .id             = -1,
498         .num_resources  = 1,
499 };
500
501 static int bq4802_probe(struct platform_device *op)
502 {
503
504         printk(KERN_INFO "%s: BQ4802 regs at 0x%llx\n",
505                op->dev.of_node->full_name, op->resource[0].start);
506
507         rtc_bq4802_device.resource = &op->resource[0];
508         return platform_device_register(&rtc_bq4802_device);
509 }
510
511 static const struct of_device_id bq4802_match[] = {
512         {
513                 .name = "rtc",
514                 .compatible = "bq4802",
515         },
516         {},
517 };
518
519 static struct platform_driver bq4802_driver = {
520         .probe          = bq4802_probe,
521         .driver = {
522                 .name = "bq4802",
523                 .of_match_table = bq4802_match,
524         },
525 };
526
527 static unsigned char mostek_read_byte(struct device *dev, u32 ofs)
528 {
529         struct platform_device *pdev = to_platform_device(dev);
530         void __iomem *regs = (void __iomem *) pdev->resource[0].start;
531
532         return readb(regs + ofs);
533 }
534
535 static void mostek_write_byte(struct device *dev, u32 ofs, u8 val)
536 {
537         struct platform_device *pdev = to_platform_device(dev);
538         void __iomem *regs = (void __iomem *) pdev->resource[0].start;
539
540         writeb(val, regs + ofs);
541 }
542
543 static struct m48t59_plat_data m48t59_data = {
544         .read_byte      = mostek_read_byte,
545         .write_byte     = mostek_write_byte,
546 };
547
548 static struct platform_device m48t59_rtc = {
549         .name           = "rtc-m48t59",
550         .id             = 0,
551         .num_resources  = 1,
552         .dev    = {
553                 .platform_data = &m48t59_data,
554         },
555 };
556
557 static int mostek_probe(struct platform_device *op)
558 {
559         struct device_node *dp = op->dev.of_node;
560
561         /* On an Enterprise system there can be multiple mostek clocks.
562          * We should only match the one that is on the central FHC bus.
563          */
564         if (!strcmp(dp->parent->name, "fhc") &&
565             strcmp(dp->parent->parent->name, "central") != 0)
566                 return -ENODEV;
567
568         printk(KERN_INFO "%s: Mostek regs at 0x%llx\n",
569                dp->full_name, op->resource[0].start);
570
571         m48t59_rtc.resource = &op->resource[0];
572         return platform_device_register(&m48t59_rtc);
573 }
574
575 static const struct of_device_id mostek_match[] = {
576         {
577                 .name = "eeprom",
578         },
579         {},
580 };
581
582 static struct platform_driver mostek_driver = {
583         .probe          = mostek_probe,
584         .driver = {
585                 .name = "mostek",
586                 .of_match_table = mostek_match,
587         },
588 };
589
590 static struct platform_device rtc_sun4v_device = {
591         .name           = "rtc-sun4v",
592         .id             = -1,
593 };
594
595 static struct platform_device rtc_starfire_device = {
596         .name           = "rtc-starfire",
597         .id             = -1,
598 };
599
600 static int __init clock_init(void)
601 {
602         if (this_is_starfire)
603                 return platform_device_register(&rtc_starfire_device);
604
605         if (tlb_type == hypervisor)
606                 return platform_device_register(&rtc_sun4v_device);
607
608         (void) platform_driver_register(&rtc_driver);
609         (void) platform_driver_register(&mostek_driver);
610         (void) platform_driver_register(&bq4802_driver);
611
612         return 0;
613 }
614
615 /* Must be after subsys_initcall() so that busses are probed.  Must
616  * be before device_initcall() because things like the RTC driver
617  * need to see the clock registers.
618  */
619 fs_initcall(clock_init);
620
621 /* Return true if this is Hummingbird, aka Ultra-IIe */
622 static bool is_hummingbird(void)
623 {
624         unsigned long ver, manuf, impl;
625
626         __asm__ __volatile__ ("rdpr %%ver, %0"
627                               : "=&r" (ver));
628         manuf = ((ver >> 48) & 0xffff);
629         impl = ((ver >> 32) & 0xffff);
630
631         return (manuf == 0x17 && impl == 0x13);
632 }
633
634 struct freq_table {
635         unsigned long clock_tick_ref;
636         unsigned int ref_freq;
637 };
638 static DEFINE_PER_CPU(struct freq_table, sparc64_freq_table) = { 0, 0 };
639
640 unsigned long sparc64_get_clock_tick(unsigned int cpu)
641 {
642         struct freq_table *ft = &per_cpu(sparc64_freq_table, cpu);
643
644         if (ft->clock_tick_ref)
645                 return ft->clock_tick_ref;
646         return cpu_data(cpu).clock_tick;
647 }
648 EXPORT_SYMBOL(sparc64_get_clock_tick);
649
650 #ifdef CONFIG_CPU_FREQ
651
652 static int sparc64_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
653                                     void *data)
654 {
655         struct cpufreq_freqs *freq = data;
656         unsigned int cpu = freq->cpu;
657         struct freq_table *ft = &per_cpu(sparc64_freq_table, cpu);
658
659         if (!ft->ref_freq) {
660                 ft->ref_freq = freq->old;
661                 ft->clock_tick_ref = cpu_data(cpu).clock_tick;
662         }
663         if ((val == CPUFREQ_PRECHANGE  && freq->old < freq->new) ||
664             (val == CPUFREQ_POSTCHANGE && freq->old > freq->new)) {
665                 cpu_data(cpu).clock_tick =
666                         cpufreq_scale(ft->clock_tick_ref,
667                                       ft->ref_freq,
668                                       freq->new);
669         }
670
671         return 0;
672 }
673
674 static struct notifier_block sparc64_cpufreq_notifier_block = {
675         .notifier_call  = sparc64_cpufreq_notifier
676 };
677
678 static int __init register_sparc64_cpufreq_notifier(void)
679 {
680
681         cpufreq_register_notifier(&sparc64_cpufreq_notifier_block,
682                                   CPUFREQ_TRANSITION_NOTIFIER);
683         return 0;
684 }
685
686 core_initcall(register_sparc64_cpufreq_notifier);
687
688 #endif /* CONFIG_CPU_FREQ */
689
690 static int sparc64_next_event(unsigned long delta,
691                               struct clock_event_device *evt)
692 {
693         return tick_operations.add_compare(delta) ? -ETIME : 0;
694 }
695
696 static int sparc64_timer_shutdown(struct clock_event_device *evt)
697 {
698         tick_operations.disable_irq();
699         return 0;
700 }
701
702 static struct clock_event_device sparc64_clockevent = {
703         .features               = CLOCK_EVT_FEAT_ONESHOT,
704         .set_state_shutdown     = sparc64_timer_shutdown,
705         .set_next_event         = sparc64_next_event,
706         .rating                 = 100,
707         .shift                  = 30,
708         .irq                    = -1,
709 };
710 static DEFINE_PER_CPU(struct clock_event_device, sparc64_events);
711
712 void __irq_entry timer_interrupt(int irq, struct pt_regs *regs)
713 {
714         struct pt_regs *old_regs = set_irq_regs(regs);
715         unsigned long tick_mask = tick_operations.softint_mask;
716         int cpu = smp_processor_id();
717         struct clock_event_device *evt = &per_cpu(sparc64_events, cpu);
718
719         clear_softint(tick_mask);
720
721         irq_enter();
722
723         local_cpu_data().irq0_irqs++;
724         kstat_incr_irq_this_cpu(0);
725
726         if (unlikely(!evt->event_handler)) {
727                 printk(KERN_WARNING
728                        "Spurious SPARC64 timer interrupt on cpu %d\n", cpu);
729         } else
730                 evt->event_handler(evt);
731
732         irq_exit();
733
734         set_irq_regs(old_regs);
735 }
736
737 void setup_sparc64_timer(void)
738 {
739         struct clock_event_device *sevt;
740         unsigned long pstate;
741
742         /* Guarantee that the following sequences execute
743          * uninterrupted.
744          */
745         __asm__ __volatile__("rdpr      %%pstate, %0\n\t"
746                              "wrpr      %0, %1, %%pstate"
747                              : "=r" (pstate)
748                              : "i" (PSTATE_IE));
749
750         tick_operations.init_tick();
751
752         /* Restore PSTATE_IE. */
753         __asm__ __volatile__("wrpr      %0, 0x0, %%pstate"
754                              : /* no outputs */
755                              : "r" (pstate));
756
757         sevt = this_cpu_ptr(&sparc64_events);
758
759         memcpy(sevt, &sparc64_clockevent, sizeof(*sevt));
760         sevt->cpumask = cpumask_of(smp_processor_id());
761
762         clockevents_register_device(sevt);
763 }
764
765 #define SPARC64_NSEC_PER_CYC_SHIFT      10UL
766
767 static struct clocksource clocksource_tick = {
768         .rating         = 100,
769         .mask           = CLOCKSOURCE_MASK(64),
770         .flags          = CLOCK_SOURCE_IS_CONTINUOUS,
771 };
772
773 static unsigned long tb_ticks_per_usec __read_mostly;
774
775 void __delay(unsigned long loops)
776 {
777         unsigned long bclock = get_tick();
778
779         while ((get_tick() - bclock) < loops)
780                 ;
781 }
782 EXPORT_SYMBOL(__delay);
783
784 void udelay(unsigned long usecs)
785 {
786         __delay(tb_ticks_per_usec * usecs);
787 }
788 EXPORT_SYMBOL(udelay);
789
790 static u64 clocksource_tick_read(struct clocksource *cs)
791 {
792         return get_tick();
793 }
794
795 static void __init get_tick_patch(void)
796 {
797         unsigned int *addr, *instr, i;
798         struct get_tick_patch *p;
799
800         if (tlb_type == spitfire && is_hummingbird())
801                 return;
802
803         for (p = &__get_tick_patch; p < &__get_tick_patch_end; p++) {
804                 instr = (tlb_type == spitfire) ? p->tick : p->stick;
805                 addr = (unsigned int *)(unsigned long)p->addr;
806                 for (i = 0; i < GET_TICK_NINSTR; i++) {
807                         addr[i] = instr[i];
808                         /* ensure that address is modified before flush */
809                         wmb();
810                         flushi(&addr[i]);
811                 }
812         }
813 }
814
815 static void __init init_tick_ops(struct sparc64_tick_ops *ops)
816 {
817         unsigned long freq, quotient, tick;
818
819         freq = ops->get_frequency();
820         quotient = clocksource_hz2mult(freq, SPARC64_NSEC_PER_CYC_SHIFT);
821         tick = ops->get_tick();
822
823         ops->offset = (tick * quotient) >> SPARC64_NSEC_PER_CYC_SHIFT;
824         ops->ticks_per_nsec_quotient = quotient;
825         ops->frequency = freq;
826         tick_operations = *ops;
827         get_tick_patch();
828 }
829
830 void __init time_init_early(void)
831 {
832         if (tlb_type == spitfire) {
833                 if (is_hummingbird()) {
834                         init_tick_ops(&hbtick_operations);
835                         clocksource_tick.archdata.vclock_mode = VCLOCK_NONE;
836                 } else {
837                         init_tick_ops(&tick_operations);
838                         clocksource_tick.archdata.vclock_mode = VCLOCK_TICK;
839                 }
840         } else {
841                 init_tick_ops(&stick_operations);
842                 clocksource_tick.archdata.vclock_mode = VCLOCK_STICK;
843         }
844 }
845
846 void __init time_init(void)
847 {
848         unsigned long freq;
849
850         freq = tick_operations.frequency;
851         tb_ticks_per_usec = freq / USEC_PER_SEC;
852
853         clocksource_tick.name = tick_operations.name;
854         clocksource_tick.read = clocksource_tick_read;
855
856         clocksource_register_hz(&clocksource_tick, freq);
857         printk("clocksource: mult[%x] shift[%d]\n",
858                clocksource_tick.mult, clocksource_tick.shift);
859
860         sparc64_clockevent.name = tick_operations.name;
861         clockevents_calc_mult_shift(&sparc64_clockevent, freq, 4);
862
863         sparc64_clockevent.max_delta_ns =
864                 clockevent_delta2ns(0x7fffffffffffffffUL, &sparc64_clockevent);
865         sparc64_clockevent.max_delta_ticks = 0x7fffffffffffffffUL;
866         sparc64_clockevent.min_delta_ns =
867                 clockevent_delta2ns(0xF, &sparc64_clockevent);
868         sparc64_clockevent.min_delta_ticks = 0xF;
869
870         printk("clockevent: mult[%x] shift[%d]\n",
871                sparc64_clockevent.mult, sparc64_clockevent.shift);
872
873         setup_sparc64_timer();
874 }
875
876 unsigned long long sched_clock(void)
877 {
878         unsigned long quotient = tick_operations.ticks_per_nsec_quotient;
879         unsigned long offset = tick_operations.offset;
880
881         /* Use barrier so the compiler emits the loads first and overlaps load
882          * latency with reading tick, because reading %tick/%stick is a
883          * post-sync instruction that will flush and restart subsequent
884          * instructions after it commits.
885          */
886         barrier();
887
888         return ((get_tick() * quotient) >> SPARC64_NSEC_PER_CYC_SHIFT) - offset;
889 }
890
891 int read_current_timer(unsigned long *timer_val)
892 {
893         *timer_val = get_tick();
894         return 0;
895 }