1 /* time.c: UltraSparc timer and TOD clock support.
3 * Copyright (C) 1997, 2008 David S. Miller (davem@davemloft.net)
4 * Copyright (C) 1998 Eddie C. Dost (ecd@skynet.be)
6 * Based largely on code which is:
8 * Copyright (C) 1996 Thomas K. Dyas (tdyas@eden.rutgers.edu)
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>
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>
39 #include <asm/oplib.h>
40 #include <asm/timer.h>
44 #include <asm/starfire.h>
46 #include <asm/sections.h>
47 #include <asm/cpudata.h>
48 #include <asm/uaccess.h>
49 #include <asm/irq_regs.h>
53 DEFINE_SPINLOCK(rtc_lock
);
55 #define TICK_PRIV_BIT (1UL << 63)
56 #define TICKCMP_IRQ_BIT (1UL << 63)
59 unsigned long profile_pc(struct pt_regs
*regs
)
61 unsigned long pc
= instruction_pointer(regs
);
63 if (in_lock_functions(pc
))
64 return regs
->u_regs
[UREG_RETPC
];
67 EXPORT_SYMBOL(profile_pc
);
70 static void tick_disable_protection(void)
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.
80 "1: rd %%tick, %%g2\n"
81 " add %%g2, 6, %%g2\n"
82 " andn %%g2, %0, %%g2\n"
83 " wrpr %%g2, 0, %%tick\n"
90 static void tick_disable_irq(void)
96 "1: wr %0, 0x0, %%tick_cmpr\n"
97 " rd %%tick_cmpr, %%g0"
99 : "r" (TICKCMP_IRQ_BIT
));
102 static void tick_init_tick(void)
104 tick_disable_protection();
108 static unsigned long long tick_get_tick(void)
112 __asm__
__volatile__("rd %%tick, %0\n\t"
116 return ret
& ~TICK_PRIV_BIT
;
119 static int tick_add_compare(unsigned long adj
)
121 unsigned long orig_tick
, new_tick
, new_compare
;
123 __asm__
__volatile__("rd %%tick, %0"
126 orig_tick
&= ~TICKCMP_IRQ_BIT
;
128 /* Workaround for Spitfire Errata (#54 I think??), I discovered
129 * this via Sun BugID 4008234, mentioned in Solaris-2.5.1 patch
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
137 __asm__
__volatile__("ba,pt %%xcc, 1f\n\t"
138 " add %1, %2, %0\n\t"
141 "wr %0, 0, %%tick_cmpr\n\t"
142 "rd %%tick_cmpr, %%g0\n\t"
144 : "r" (orig_tick
), "r" (adj
));
146 __asm__
__volatile__("rd %%tick, %0"
148 new_tick
&= ~TICKCMP_IRQ_BIT
;
150 return ((long)(new_tick
- (orig_tick
+adj
))) > 0L;
153 static unsigned long tick_add_tick(unsigned long adj
)
155 unsigned long new_tick
;
157 /* Also need to handle Blackbird bug here too. */
158 __asm__
__volatile__("rd %%tick, %0\n\t"
160 "wrpr %0, 0, %%tick\n\t"
167 static struct sparc64_tick_ops tick_operations __read_mostly
= {
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,
177 struct sparc64_tick_ops
*tick_ops __read_mostly
= &tick_operations
;
178 EXPORT_SYMBOL(tick_ops
);
180 static void stick_disable_irq(void)
182 __asm__
__volatile__(
183 "wr %0, 0x0, %%asr25"
185 : "r" (TICKCMP_IRQ_BIT
));
188 static void stick_init_tick(void)
190 /* Writes to the %tick and %stick register are not
191 * allowed on sun4v. The Hypervisor controls that
194 if (tlb_type
!= hypervisor
) {
195 tick_disable_protection();
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"
204 : "r" (TICK_PRIV_BIT
)
211 static unsigned long long stick_get_tick(void)
215 __asm__
__volatile__("rd %%asr24, %0"
218 return ret
& ~TICK_PRIV_BIT
;
221 static unsigned long stick_add_tick(unsigned long adj
)
223 unsigned long new_tick
;
225 __asm__
__volatile__("rd %%asr24, %0\n\t"
227 "wr %0, 0, %%asr24\n\t"
234 static int stick_add_compare(unsigned long adj
)
236 unsigned long orig_tick
, new_tick
;
238 __asm__
__volatile__("rd %%asr24, %0"
240 orig_tick
&= ~TICKCMP_IRQ_BIT
;
242 __asm__
__volatile__("wr %0, 0, %%asr25"
244 : "r" (orig_tick
+ adj
));
246 __asm__
__volatile__("rd %%asr24, %0"
248 new_tick
&= ~TICKCMP_IRQ_BIT
;
250 return ((long)(new_tick
- (orig_tick
+adj
))) > 0L;
253 static struct sparc64_tick_ops stick_operations __read_mostly
= {
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,
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
268 * Since STICK is constantly updating, we have to access it carefully.
270 * The sequence we use to read is:
273 * 3) read high again, if it rolled re-read both low and high again.
275 * Writing STICK safely is also tricky:
276 * 1) write low to zero
280 #define HBIRD_STICKCMP_ADDR 0x1fe0000f060UL
281 #define HBIRD_STICK_ADDR 0x1fe0000f070UL
283 static unsigned long __hbird_read_stick(void)
285 unsigned long ret
, tmp1
, tmp2
, tmp3
;
286 unsigned long addr
= HBIRD_STICK_ADDR
+8;
288 __asm__
__volatile__("ldxa [%1] %5, %2\n"
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"
295 "bne,a,pn %%xcc, 1b\n\t"
297 "sllx %4, 32, %4\n\t"
299 : "=&r" (ret
), "=&r" (addr
),
300 "=&r" (tmp1
), "=&r" (tmp2
), "=&r" (tmp3
)
301 : "i" (ASI_PHYS_BYPASS_EC_E
), "1" (addr
));
306 static void __hbird_write_stick(unsigned long val
)
308 unsigned long low
= (val
& 0xffffffffUL
);
309 unsigned long high
= (val
>> 32UL);
310 unsigned long addr
= HBIRD_STICK_ADDR
;
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"
318 : "0" (addr
), "r" (low
), "r" (high
),
319 "i" (ASI_PHYS_BYPASS_EC_E
));
322 static void __hbird_write_compare(unsigned long val
)
324 unsigned long low
= (val
& 0xffffffffUL
);
325 unsigned long high
= (val
>> 32UL);
326 unsigned long addr
= HBIRD_STICKCMP_ADDR
+ 0x8UL
;
328 __asm__
__volatile__("stxa %3, [%0] %4\n\t"
329 "sub %0, 0x8, %0\n\t"
332 : "0" (addr
), "r" (low
), "r" (high
),
333 "i" (ASI_PHYS_BYPASS_EC_E
));
336 static void hbtick_disable_irq(void)
338 __hbird_write_compare(TICKCMP_IRQ_BIT
);
341 static void hbtick_init_tick(void)
343 tick_disable_protection();
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
350 __hbird_write_stick(__hbird_read_stick());
352 hbtick_disable_irq();
355 static unsigned long long hbtick_get_tick(void)
357 return __hbird_read_stick() & ~TICK_PRIV_BIT
;
360 static unsigned long hbtick_add_tick(unsigned long adj
)
364 val
= __hbird_read_stick() + adj
;
365 __hbird_write_stick(val
);
370 static int hbtick_add_compare(unsigned long adj
)
372 unsigned long val
= __hbird_read_stick();
375 val
&= ~TICKCMP_IRQ_BIT
;
377 __hbird_write_compare(val
);
379 val2
= __hbird_read_stick() & ~TICKCMP_IRQ_BIT
;
381 return ((long)(val2
- val
)) > 0L;
384 static struct sparc64_tick_ops hbtick_operations __read_mostly
= {
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,
394 static unsigned long timer_ticks_per_nsec_quotient __read_mostly
;
396 unsigned long cmos_regs
;
397 EXPORT_SYMBOL(cmos_regs
);
399 static struct resource rtc_cmos_resource
;
401 static struct platform_device rtc_cmos_device
= {
404 .resource
= &rtc_cmos_resource
,
408 static int rtc_probe(struct platform_device
*op
)
412 printk(KERN_INFO
"%s: RTC regs at 0x%llx\n",
413 op
->dev
.of_node
->full_name
, op
->resource
[0].start
);
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.
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
;
427 cmos_regs
= op
->resource
[0].start
;
428 return platform_device_register(&rtc_cmos_device
);
431 static const struct of_device_id rtc_match
[] = {
434 .compatible
= "m5819",
438 .compatible
= "isa-m5819p",
442 .compatible
= "isa-m5823p",
446 .compatible
= "ds1287",
451 static struct platform_driver rtc_driver
= {
455 .of_match_table
= rtc_match
,
459 static struct platform_device rtc_bq4802_device
= {
460 .name
= "rtc-bq4802",
465 static int bq4802_probe(struct platform_device
*op
)
468 printk(KERN_INFO
"%s: BQ4802 regs at 0x%llx\n",
469 op
->dev
.of_node
->full_name
, op
->resource
[0].start
);
471 rtc_bq4802_device
.resource
= &op
->resource
[0];
472 return platform_device_register(&rtc_bq4802_device
);
475 static const struct of_device_id bq4802_match
[] = {
478 .compatible
= "bq4802",
483 static struct platform_driver bq4802_driver
= {
484 .probe
= bq4802_probe
,
487 .of_match_table
= bq4802_match
,
491 static unsigned char mostek_read_byte(struct device
*dev
, u32 ofs
)
493 struct platform_device
*pdev
= to_platform_device(dev
);
494 void __iomem
*regs
= (void __iomem
*) pdev
->resource
[0].start
;
496 return readb(regs
+ ofs
);
499 static void mostek_write_byte(struct device
*dev
, u32 ofs
, u8 val
)
501 struct platform_device
*pdev
= to_platform_device(dev
);
502 void __iomem
*regs
= (void __iomem
*) pdev
->resource
[0].start
;
504 writeb(val
, regs
+ ofs
);
507 static struct m48t59_plat_data m48t59_data
= {
508 .read_byte
= mostek_read_byte
,
509 .write_byte
= mostek_write_byte
,
512 static struct platform_device m48t59_rtc
= {
513 .name
= "rtc-m48t59",
517 .platform_data
= &m48t59_data
,
521 static int mostek_probe(struct platform_device
*op
)
523 struct device_node
*dp
= op
->dev
.of_node
;
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.
528 if (!strcmp(dp
->parent
->name
, "fhc") &&
529 strcmp(dp
->parent
->parent
->name
, "central") != 0)
532 printk(KERN_INFO
"%s: Mostek regs at 0x%llx\n",
533 dp
->full_name
, op
->resource
[0].start
);
535 m48t59_rtc
.resource
= &op
->resource
[0];
536 return platform_device_register(&m48t59_rtc
);
539 static const struct of_device_id mostek_match
[] = {
546 static struct platform_driver mostek_driver
= {
547 .probe
= mostek_probe
,
550 .of_match_table
= mostek_match
,
554 static struct platform_device rtc_sun4v_device
= {
559 static struct platform_device rtc_starfire_device
= {
560 .name
= "rtc-starfire",
564 static int __init
clock_init(void)
566 if (this_is_starfire
)
567 return platform_device_register(&rtc_starfire_device
);
569 if (tlb_type
== hypervisor
)
570 return platform_device_register(&rtc_sun4v_device
);
572 (void) platform_driver_register(&rtc_driver
);
573 (void) platform_driver_register(&mostek_driver
);
574 (void) platform_driver_register(&bq4802_driver
);
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.
583 fs_initcall(clock_init
);
585 /* This is gets the master TICK_INT timer going. */
586 static unsigned long sparc64_init_timers(void)
588 struct device_node
*dp
;
591 dp
= of_find_node_by_path("/");
592 if (tlb_type
== spitfire
) {
593 unsigned long ver
, manuf
, impl
;
595 __asm__
__volatile__ ("rdpr %%ver, %0"
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);
604 tick_ops
= &tick_operations
;
605 freq
= local_cpu_data().clock_tick
;
608 tick_ops
= &stick_operations
;
609 freq
= of_getintprop_default(dp
, "stick-frequency", 0);
616 unsigned long clock_tick_ref
;
617 unsigned int ref_freq
;
619 static DEFINE_PER_CPU(struct freq_table
, sparc64_freq_table
) = { 0, 0 };
621 unsigned long sparc64_get_clock_tick(unsigned int cpu
)
623 struct freq_table
*ft
= &per_cpu(sparc64_freq_table
, cpu
);
625 if (ft
->clock_tick_ref
)
626 return ft
->clock_tick_ref
;
627 return cpu_data(cpu
).clock_tick
;
629 EXPORT_SYMBOL(sparc64_get_clock_tick
);
631 #ifdef CONFIG_CPU_FREQ
633 static int sparc64_cpufreq_notifier(struct notifier_block
*nb
, unsigned long val
,
636 struct cpufreq_freqs
*freq
= data
;
637 unsigned int cpu
= freq
->cpu
;
638 struct freq_table
*ft
= &per_cpu(sparc64_freq_table
, cpu
);
641 ft
->ref_freq
= freq
->old
;
642 ft
->clock_tick_ref
= cpu_data(cpu
).clock_tick
;
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
,
655 static struct notifier_block sparc64_cpufreq_notifier_block
= {
656 .notifier_call
= sparc64_cpufreq_notifier
659 static int __init
register_sparc64_cpufreq_notifier(void)
662 cpufreq_register_notifier(&sparc64_cpufreq_notifier_block
,
663 CPUFREQ_TRANSITION_NOTIFIER
);
667 core_initcall(register_sparc64_cpufreq_notifier
);
669 #endif /* CONFIG_CPU_FREQ */
671 static int sparc64_next_event(unsigned long delta
,
672 struct clock_event_device
*evt
)
674 return tick_ops
->add_compare(delta
) ? -ETIME
: 0;
677 static int sparc64_timer_shutdown(struct clock_event_device
*evt
)
679 tick_ops
->disable_irq();
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
,
691 static DEFINE_PER_CPU(struct clock_event_device
, sparc64_events
);
693 void __irq_entry
timer_interrupt(int irq
, struct pt_regs
*regs
)
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
);
700 clear_softint(tick_mask
);
704 local_cpu_data().irq0_irqs
++;
705 kstat_incr_irq_this_cpu(0);
707 if (unlikely(!evt
->event_handler
)) {
709 "Spurious SPARC64 timer interrupt on cpu %d\n", cpu
);
711 evt
->event_handler(evt
);
715 set_irq_regs(old_regs
);
718 void setup_sparc64_timer(void)
720 struct clock_event_device
*sevt
;
721 unsigned long pstate
;
723 /* Guarantee that the following sequences execute
726 __asm__
__volatile__("rdpr %%pstate, %0\n\t"
727 "wrpr %0, %1, %%pstate"
731 tick_ops
->init_tick();
733 /* Restore PSTATE_IE. */
734 __asm__
__volatile__("wrpr %0, 0x0, %%pstate"
738 sevt
= this_cpu_ptr(&sparc64_events
);
740 memcpy(sevt
, &sparc64_clockevent
, sizeof(*sevt
));
741 sevt
->cpumask
= cpumask_of(smp_processor_id());
743 clockevents_register_device(sevt
);
746 #define SPARC64_NSEC_PER_CYC_SHIFT 10UL
748 static struct clocksource clocksource_tick
= {
750 .mask
= CLOCKSOURCE_MASK(64),
751 .flags
= CLOCK_SOURCE_IS_CONTINUOUS
,
754 static unsigned long tb_ticks_per_usec __read_mostly
;
756 void __delay(unsigned long loops
)
758 unsigned long bclock
, now
;
760 bclock
= tick_ops
->get_tick();
762 now
= tick_ops
->get_tick();
763 } while ((now
-bclock
) < loops
);
765 EXPORT_SYMBOL(__delay
);
767 void udelay(unsigned long usecs
)
769 __delay(tb_ticks_per_usec
* usecs
);
771 EXPORT_SYMBOL(udelay
);
773 static cycle_t
clocksource_tick_read(struct clocksource
*cs
)
775 return tick_ops
->get_tick();
778 void __init
time_init(void)
780 unsigned long freq
= sparc64_init_timers();
782 tb_ticks_per_usec
= freq
/ USEC_PER_SEC
;
784 timer_ticks_per_nsec_quotient
=
785 clocksource_hz2mult(freq
, SPARC64_NSEC_PER_CYC_SHIFT
);
787 clocksource_tick
.name
= tick_ops
->name
;
788 clocksource_tick
.read
= clocksource_tick_read
;
790 clocksource_register_hz(&clocksource_tick
, freq
);
791 printk("clocksource: mult[%x] shift[%d]\n",
792 clocksource_tick
.mult
, clocksource_tick
.shift
);
794 sparc64_clockevent
.name
= tick_ops
->name
;
795 clockevents_calc_mult_shift(&sparc64_clockevent
, freq
, 4);
797 sparc64_clockevent
.max_delta_ns
=
798 clockevent_delta2ns(0x7fffffffffffffffUL
, &sparc64_clockevent
);
799 sparc64_clockevent
.min_delta_ns
=
800 clockevent_delta2ns(0xF, &sparc64_clockevent
);
802 printk("clockevent: mult[%x] shift[%d]\n",
803 sparc64_clockevent
.mult
, sparc64_clockevent
.shift
);
805 setup_sparc64_timer();
808 unsigned long long sched_clock(void)
810 unsigned long ticks
= tick_ops
->get_tick();
812 return (ticks
* timer_ticks_per_nsec_quotient
)
813 >> SPARC64_NSEC_PER_CYC_SHIFT
;
816 int read_current_timer(unsigned long *timer_val
)
818 *timer_val
= tick_ops
->get_tick();