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/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>
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>
40 #include <asm/oplib.h>
41 #include <asm/timer.h>
45 #include <asm/starfire.h>
47 #include <asm/sections.h>
48 #include <asm/cpudata.h>
49 #include <asm/uaccess.h>
50 #include <asm/irq_regs.h>
54 DEFINE_SPINLOCK(rtc_lock);
56 #define TICK_PRIV_BIT (1UL << 63)
57 #define TICKCMP_IRQ_BIT (1UL << 63)
60 unsigned long profile_pc(struct pt_regs *regs)
62 unsigned long pc = instruction_pointer(regs);
64 if (in_lock_functions(pc))
65 return regs->u_regs[UREG_RETPC];
68 EXPORT_SYMBOL(profile_pc);
71 static void tick_disable_protection(void)
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.
81 "1: rd %%tick, %%g2\n"
82 " add %%g2, 6, %%g2\n"
83 " andn %%g2, %0, %%g2\n"
84 " wrpr %%g2, 0, %%tick\n"
91 static void tick_disable_irq(void)
97 "1: wr %0, 0x0, %%tick_cmpr\n"
98 " rd %%tick_cmpr, %%g0"
100 : "r" (TICKCMP_IRQ_BIT));
103 static void tick_init_tick(void)
105 tick_disable_protection();
109 static unsigned long tick_get_tick(void)
113 __asm__ __volatile__("rd %%tick, %0\n\t"
117 return ret & ~TICK_PRIV_BIT;
120 static int tick_add_compare(unsigned long adj)
122 unsigned long orig_tick, new_tick, new_compare;
124 __asm__ __volatile__("rd %%tick, %0"
127 orig_tick &= ~TICKCMP_IRQ_BIT;
129 /* Workaround for Spitfire Errata (#54 I think??), I discovered
130 * this via Sun BugID 4008234, mentioned in Solaris-2.5.1 patch
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
138 __asm__ __volatile__("ba,pt %%xcc, 1f\n\t"
139 " add %1, %2, %0\n\t"
142 "wr %0, 0, %%tick_cmpr\n\t"
143 "rd %%tick_cmpr, %%g0\n\t"
145 : "r" (orig_tick), "r" (adj));
147 __asm__ __volatile__("rd %%tick, %0"
149 new_tick &= ~TICKCMP_IRQ_BIT;
151 return ((long)(new_tick - (orig_tick+adj))) > 0L;
154 static unsigned long tick_add_tick(unsigned long adj)
156 unsigned long new_tick;
158 /* Also need to handle Blackbird bug here too. */
159 __asm__ __volatile__("rd %%tick, %0\n\t"
161 "wrpr %0, 0, %%tick\n\t"
168 static struct sparc64_tick_ops tick_operations __read_mostly = {
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,
178 struct sparc64_tick_ops *tick_ops __read_mostly = &tick_operations;
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 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 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 int update_persistent_clock(struct timespec now)
398 struct rtc_device *rtc = rtc_class_open("rtc0");
401 return rtc_set_mmss(rtc, now.tv_sec);
406 /* davem suggests we keep this within the 4M locked kernel image */
407 static u32 starfire_get_time(void)
409 static char obp_gettod[32];
412 sprintf(obp_gettod, "h# %08x unix-gettod",
413 (unsigned int) (long) &unix_tod);
414 prom_feval(obp_gettod);
419 static int starfire_set_time(u32 val)
421 /* Do nothing, time is set using the service processor
422 * console on this platform.
427 static u32 hypervisor_get_time(void)
429 unsigned long ret, time;
433 ret = sun4v_tod_get(&time);
436 if (ret == HV_EWOULDBLOCK) {
441 printk(KERN_WARNING "SUN4V: tod_get() timed out.\n");
444 printk(KERN_WARNING "SUN4V: tod_get() not supported.\n");
448 static int hypervisor_set_time(u32 secs)
454 ret = sun4v_tod_set(secs);
457 if (ret == HV_EWOULDBLOCK) {
462 printk(KERN_WARNING "SUN4V: tod_set() timed out.\n");
465 printk(KERN_WARNING "SUN4V: tod_set() not supported.\n");
469 unsigned long cmos_regs;
470 EXPORT_SYMBOL(cmos_regs);
472 struct resource rtc_cmos_resource;
474 static struct platform_device rtc_cmos_device = {
477 .resource = &rtc_cmos_resource,
481 static int __devinit rtc_probe(struct of_device *op, const struct of_device_id *match)
485 printk(KERN_INFO "%s: RTC regs at 0x%lx\n",
486 op->node->full_name, op->resource[0].start);
488 /* The CMOS RTC driver only accepts IORESOURCE_IO, so cons
489 * up a fake resource so that the probe works for all cases.
490 * When the RTC is behind an ISA bus it will have IORESOURCE_IO
491 * already, whereas when it's behind EBUS is will be IORESOURCE_MEM.
494 r = &rtc_cmos_resource;
495 r->flags = IORESOURCE_IO;
496 r->name = op->resource[0].name;
497 r->start = op->resource[0].start;
498 r->end = op->resource[0].end;
500 cmos_regs = op->resource[0].start;
501 return platform_device_register(&rtc_cmos_device);
504 static struct of_device_id rtc_match[] = {
507 .compatible = "m5819",
511 .compatible = "isa-m5819p",
515 .compatible = "isa-m5823p",
519 .compatible = "ds1287",
524 static struct of_platform_driver rtc_driver = {
525 .match_table = rtc_match,
532 static struct platform_device rtc_bq4802_device = {
533 .name = "rtc-bq4802",
538 static int __devinit bq4802_probe(struct of_device *op, const struct of_device_id *match)
541 printk(KERN_INFO "%s: BQ4802 regs at 0x%lx\n",
542 op->node->full_name, op->resource[0].start);
544 rtc_bq4802_device.resource = &op->resource[0];
545 return platform_device_register(&rtc_bq4802_device);
548 static struct of_device_id bq4802_match[] = {
551 .compatible = "bq4802",
555 static struct of_platform_driver bq4802_driver = {
556 .match_table = bq4802_match,
557 .probe = bq4802_probe,
563 static unsigned char mostek_read_byte(struct device *dev, u32 ofs)
565 struct platform_device *pdev = to_platform_device(dev);
569 regs = (void __iomem *) pdev->resource[0].start;
570 val = readb(regs + ofs);
572 /* the year 0 is 1968 */
573 if (ofs == M48T59_YEAR) {
581 static void mostek_write_byte(struct device *dev, u32 ofs, u8 val)
583 struct platform_device *pdev = to_platform_device(dev);
586 regs = (void __iomem *) pdev->resource[0].start;
587 if (ofs == M48T59_YEAR) {
594 if ((val & 0xf0) > 0x9A)
597 writeb(val, regs + ofs);
600 static struct m48t59_plat_data m48t59_data = {
601 .read_byte = mostek_read_byte,
602 .write_byte = mostek_write_byte,
605 static struct platform_device m48t59_rtc = {
606 .name = "rtc-m48t59",
610 .platform_data = &m48t59_data,
614 static int __devinit mostek_probe(struct of_device *op, const struct of_device_id *match)
616 struct device_node *dp = op->node;
618 /* On an Enterprise system there can be multiple mostek clocks.
619 * We should only match the one that is on the central FHC bus.
621 if (!strcmp(dp->parent->name, "fhc") &&
622 strcmp(dp->parent->parent->name, "central") != 0)
625 printk(KERN_INFO "%s: Mostek regs at 0x%lx\n",
626 dp->full_name, op->resource[0].start);
628 m48t59_rtc.resource = &op->resource[0];
629 return platform_device_register(&m48t59_rtc);
632 static struct of_device_id mostek_match[] = {
639 static struct of_platform_driver mostek_driver = {
640 .match_table = mostek_match,
641 .probe = mostek_probe,
647 static int __init clock_init(void)
649 if (this_is_starfire) {
650 xtime.tv_sec = starfire_get_time();
651 xtime.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ);
652 set_normalized_timespec(&wall_to_monotonic,
653 -xtime.tv_sec, -xtime.tv_nsec);
656 if (tlb_type == hypervisor) {
657 xtime.tv_sec = hypervisor_get_time();
658 xtime.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ);
659 set_normalized_timespec(&wall_to_monotonic,
660 -xtime.tv_sec, -xtime.tv_nsec);
664 (void) of_register_driver(&rtc_driver, &of_platform_bus_type);
665 (void) of_register_driver(&mostek_driver, &of_platform_bus_type);
666 (void) of_register_driver(&bq4802_driver, &of_platform_bus_type);
671 /* Must be after subsys_initcall() so that busses are probed. Must
672 * be before device_initcall() because things like the RTC driver
673 * need to see the clock registers.
675 fs_initcall(clock_init);
677 /* This is gets the master TICK_INT timer going. */
678 static unsigned long sparc64_init_timers(void)
680 struct device_node *dp;
683 dp = of_find_node_by_path("/");
684 if (tlb_type == spitfire) {
685 unsigned long ver, manuf, impl;
687 __asm__ __volatile__ ("rdpr %%ver, %0"
689 manuf = ((ver >> 48) & 0xffff);
690 impl = ((ver >> 32) & 0xffff);
691 if (manuf == 0x17 && impl == 0x13) {
692 /* Hummingbird, aka Ultra-IIe */
693 tick_ops = &hbtick_operations;
694 clock = of_getintprop_default(dp, "stick-frequency", 0);
696 tick_ops = &tick_operations;
697 clock = local_cpu_data().clock_tick;
700 tick_ops = &stick_operations;
701 clock = of_getintprop_default(dp, "stick-frequency", 0);
708 unsigned long clock_tick_ref;
709 unsigned int ref_freq;
711 static DEFINE_PER_CPU(struct freq_table, sparc64_freq_table) = { 0, 0 };
713 unsigned long sparc64_get_clock_tick(unsigned int cpu)
715 struct freq_table *ft = &per_cpu(sparc64_freq_table, cpu);
717 if (ft->clock_tick_ref)
718 return ft->clock_tick_ref;
719 return cpu_data(cpu).clock_tick;
722 #ifdef CONFIG_CPU_FREQ
724 static int sparc64_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
727 struct cpufreq_freqs *freq = data;
728 unsigned int cpu = freq->cpu;
729 struct freq_table *ft = &per_cpu(sparc64_freq_table, cpu);
732 ft->ref_freq = freq->old;
733 ft->clock_tick_ref = cpu_data(cpu).clock_tick;
735 if ((val == CPUFREQ_PRECHANGE && freq->old < freq->new) ||
736 (val == CPUFREQ_POSTCHANGE && freq->old > freq->new) ||
737 (val == CPUFREQ_RESUMECHANGE)) {
738 cpu_data(cpu).clock_tick =
739 cpufreq_scale(ft->clock_tick_ref,
747 static struct notifier_block sparc64_cpufreq_notifier_block = {
748 .notifier_call = sparc64_cpufreq_notifier
751 static int __init register_sparc64_cpufreq_notifier(void)
754 cpufreq_register_notifier(&sparc64_cpufreq_notifier_block,
755 CPUFREQ_TRANSITION_NOTIFIER);
759 core_initcall(register_sparc64_cpufreq_notifier);
761 #endif /* CONFIG_CPU_FREQ */
763 static int sparc64_next_event(unsigned long delta,
764 struct clock_event_device *evt)
766 return tick_ops->add_compare(delta) ? -ETIME : 0;
769 static void sparc64_timer_setup(enum clock_event_mode mode,
770 struct clock_event_device *evt)
773 case CLOCK_EVT_MODE_ONESHOT:
774 case CLOCK_EVT_MODE_RESUME:
777 case CLOCK_EVT_MODE_SHUTDOWN:
778 tick_ops->disable_irq();
781 case CLOCK_EVT_MODE_PERIODIC:
782 case CLOCK_EVT_MODE_UNUSED:
788 static struct clock_event_device sparc64_clockevent = {
789 .features = CLOCK_EVT_FEAT_ONESHOT,
790 .set_mode = sparc64_timer_setup,
791 .set_next_event = sparc64_next_event,
796 static DEFINE_PER_CPU(struct clock_event_device, sparc64_events);
798 void timer_interrupt(int irq, struct pt_regs *regs)
800 struct pt_regs *old_regs = set_irq_regs(regs);
801 unsigned long tick_mask = tick_ops->softint_mask;
802 int cpu = smp_processor_id();
803 struct clock_event_device *evt = &per_cpu(sparc64_events, cpu);
805 clear_softint(tick_mask);
809 kstat_this_cpu.irqs[0]++;
811 if (unlikely(!evt->event_handler)) {
813 "Spurious SPARC64 timer interrupt on cpu %d\n", cpu);
815 evt->event_handler(evt);
819 set_irq_regs(old_regs);
822 void __devinit setup_sparc64_timer(void)
824 struct clock_event_device *sevt;
825 unsigned long pstate;
827 /* Guarantee that the following sequences execute
830 __asm__ __volatile__("rdpr %%pstate, %0\n\t"
831 "wrpr %0, %1, %%pstate"
835 tick_ops->init_tick();
837 /* Restore PSTATE_IE. */
838 __asm__ __volatile__("wrpr %0, 0x0, %%pstate"
842 sevt = &__get_cpu_var(sparc64_events);
844 memcpy(sevt, &sparc64_clockevent, sizeof(*sevt));
845 sevt->cpumask = cpumask_of_cpu(smp_processor_id());
847 clockevents_register_device(sevt);
850 #define SPARC64_NSEC_PER_CYC_SHIFT 10UL
852 static struct clocksource clocksource_tick = {
854 .mask = CLOCKSOURCE_MASK(64),
856 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
859 static void __init setup_clockevent_multiplier(unsigned long hz)
861 unsigned long mult, shift = 32;
864 mult = div_sc(hz, NSEC_PER_SEC, shift);
865 if (mult && (mult >> 32UL) == 0UL)
871 sparc64_clockevent.shift = shift;
872 sparc64_clockevent.mult = mult;
875 static unsigned long tb_ticks_per_usec __read_mostly;
877 void __delay(unsigned long loops)
879 unsigned long bclock, now;
881 bclock = tick_ops->get_tick();
883 now = tick_ops->get_tick();
884 } while ((now-bclock) < loops);
886 EXPORT_SYMBOL(__delay);
888 void udelay(unsigned long usecs)
890 __delay(tb_ticks_per_usec * usecs);
892 EXPORT_SYMBOL(udelay);
894 void __init time_init(void)
896 unsigned long clock = sparc64_init_timers();
898 tb_ticks_per_usec = clock / USEC_PER_SEC;
900 timer_ticks_per_nsec_quotient =
901 clocksource_hz2mult(clock, SPARC64_NSEC_PER_CYC_SHIFT);
903 clocksource_tick.name = tick_ops->name;
904 clocksource_tick.mult =
905 clocksource_hz2mult(clock,
906 clocksource_tick.shift);
907 clocksource_tick.read = tick_ops->get_tick;
909 printk("clocksource: mult[%x] shift[%d]\n",
910 clocksource_tick.mult, clocksource_tick.shift);
912 clocksource_register(&clocksource_tick);
914 sparc64_clockevent.name = tick_ops->name;
916 setup_clockevent_multiplier(clock);
918 sparc64_clockevent.max_delta_ns =
919 clockevent_delta2ns(0x7fffffffffffffffUL, &sparc64_clockevent);
920 sparc64_clockevent.min_delta_ns =
921 clockevent_delta2ns(0xF, &sparc64_clockevent);
923 printk("clockevent: mult[%lx] shift[%d]\n",
924 sparc64_clockevent.mult, sparc64_clockevent.shift);
926 setup_sparc64_timer();
929 unsigned long long sched_clock(void)
931 unsigned long ticks = tick_ops->get_tick();
933 return (ticks * timer_ticks_per_nsec_quotient)
934 >> SPARC64_NSEC_PER_CYC_SHIFT;
937 #define RTC_IS_OPEN 0x01 /* means /dev/rtc is in use */
938 static unsigned char mini_rtc_status; /* bitmapped status byte. */
941 #define STARTOFTIME 1970
942 #define SECDAY 86400L
943 #define SECYR (SECDAY * 365)
944 #define leapyear(year) ((year) % 4 == 0 && \
945 ((year) % 100 != 0 || (year) % 400 == 0))
946 #define days_in_year(a) (leapyear(a) ? 366 : 365)
947 #define days_in_month(a) (month_days[(a) - 1])
949 static int month_days[12] = {
950 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
954 * This only works for the Gregorian calendar - i.e. after 1752 (in the UK)
956 static void GregorianDay(struct rtc_time * tm)
961 int MonthOffset[] = { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 };
963 lastYear = tm->tm_year - 1;
966 * Number of leap corrections to apply up to end of last year
968 leapsToDate = lastYear / 4 - lastYear / 100 + lastYear / 400;
971 * This year is a leap year if it is divisible by 4 except when it is
972 * divisible by 100 unless it is divisible by 400
974 * e.g. 1904 was a leap year, 1900 was not, 1996 is, and 2000 was
976 day = tm->tm_mon > 2 && leapyear(tm->tm_year);
978 day += lastYear*365 + leapsToDate + MonthOffset[tm->tm_mon-1] +
981 tm->tm_wday = day % 7;
984 static void to_tm(int tim, struct rtc_time *tm)
987 register long hms, day;
992 /* Hours, minutes, seconds are easy */
993 tm->tm_hour = hms / 3600;
994 tm->tm_min = (hms % 3600) / 60;
995 tm->tm_sec = (hms % 3600) % 60;
997 /* Number of years in days */
998 for (i = STARTOFTIME; day >= days_in_year(i); i++)
999 day -= days_in_year(i);
1002 /* Number of months in days left */
1003 if (leapyear(tm->tm_year))
1004 days_in_month(FEBRUARY) = 29;
1005 for (i = 1; day >= days_in_month(i); i++)
1006 day -= days_in_month(i);
1007 days_in_month(FEBRUARY) = 28;
1010 /* Days are what is left over (+1) from all that. */
1011 tm->tm_mday = day + 1;
1014 * Determine the day of week
1019 /* Both Starfire and SUN4V give us seconds since Jan 1st, 1970,
1020 * aka Unix time. So we have to convert to/from rtc_time.
1022 static void starfire_get_rtc_time(struct rtc_time *time)
1024 u32 seconds = starfire_get_time();
1026 to_tm(seconds, time);
1027 time->tm_year -= 1900;
1031 static int starfire_set_rtc_time(struct rtc_time *time)
1033 u32 seconds = mktime(time->tm_year + 1900, time->tm_mon + 1,
1034 time->tm_mday, time->tm_hour,
1035 time->tm_min, time->tm_sec);
1037 return starfire_set_time(seconds);
1040 static void hypervisor_get_rtc_time(struct rtc_time *time)
1042 u32 seconds = hypervisor_get_time();
1044 to_tm(seconds, time);
1045 time->tm_year -= 1900;
1049 static int hypervisor_set_rtc_time(struct rtc_time *time)
1051 u32 seconds = mktime(time->tm_year + 1900, time->tm_mon + 1,
1052 time->tm_mday, time->tm_hour,
1053 time->tm_min, time->tm_sec);
1055 return hypervisor_set_time(seconds);
1058 struct mini_rtc_ops {
1059 void (*get_rtc_time)(struct rtc_time *);
1060 int (*set_rtc_time)(struct rtc_time *);
1063 static struct mini_rtc_ops starfire_rtc_ops = {
1064 .get_rtc_time = starfire_get_rtc_time,
1065 .set_rtc_time = starfire_set_rtc_time,
1068 static struct mini_rtc_ops hypervisor_rtc_ops = {
1069 .get_rtc_time = hypervisor_get_rtc_time,
1070 .set_rtc_time = hypervisor_set_rtc_time,
1073 static struct mini_rtc_ops *mini_rtc_ops;
1075 static inline void mini_get_rtc_time(struct rtc_time *time)
1077 unsigned long flags;
1079 spin_lock_irqsave(&rtc_lock, flags);
1080 mini_rtc_ops->get_rtc_time(time);
1081 spin_unlock_irqrestore(&rtc_lock, flags);
1084 static inline int mini_set_rtc_time(struct rtc_time *time)
1086 unsigned long flags;
1089 spin_lock_irqsave(&rtc_lock, flags);
1090 err = mini_rtc_ops->set_rtc_time(time);
1091 spin_unlock_irqrestore(&rtc_lock, flags);
1096 static int mini_rtc_ioctl(struct inode *inode, struct file *file,
1097 unsigned int cmd, unsigned long arg)
1099 struct rtc_time wtime;
1100 void __user *argp = (void __user *)arg;
1110 case RTC_UIE_OFF: /* disable ints from RTC updates. */
1113 case RTC_UIE_ON: /* enable ints for RTC updates. */
1116 case RTC_RD_TIME: /* Read the time/date from RTC */
1117 /* this doesn't get week-day, who cares */
1118 memset(&wtime, 0, sizeof(wtime));
1119 mini_get_rtc_time(&wtime);
1121 return copy_to_user(argp, &wtime, sizeof(wtime)) ? -EFAULT : 0;
1123 case RTC_SET_TIME: /* Set the RTC */
1127 if (!capable(CAP_SYS_TIME))
1130 if (copy_from_user(&wtime, argp, sizeof(wtime)))
1133 year = wtime.tm_year + 1900;
1134 days = month_days[wtime.tm_mon] +
1135 ((wtime.tm_mon == 1) && leapyear(year));
1137 if ((wtime.tm_mon < 0 || wtime.tm_mon > 11) ||
1138 (wtime.tm_mday < 1))
1141 if (wtime.tm_mday < 0 || wtime.tm_mday > days)
1144 if (wtime.tm_hour < 0 || wtime.tm_hour >= 24 ||
1145 wtime.tm_min < 0 || wtime.tm_min >= 60 ||
1146 wtime.tm_sec < 0 || wtime.tm_sec >= 60)
1149 return mini_set_rtc_time(&wtime);
1156 static int mini_rtc_open(struct inode *inode, struct file *file)
1159 if (mini_rtc_status & RTC_IS_OPEN) {
1164 mini_rtc_status |= RTC_IS_OPEN;
1170 static int mini_rtc_release(struct inode *inode, struct file *file)
1172 mini_rtc_status &= ~RTC_IS_OPEN;
1177 static const struct file_operations mini_rtc_fops = {
1178 .owner = THIS_MODULE,
1179 .ioctl = mini_rtc_ioctl,
1180 .open = mini_rtc_open,
1181 .release = mini_rtc_release,
1184 static struct miscdevice rtc_mini_dev =
1188 .fops = &mini_rtc_fops,
1191 static int __init rtc_mini_init(void)
1195 if (tlb_type == hypervisor)
1196 mini_rtc_ops = &hypervisor_rtc_ops;
1197 else if (this_is_starfire)
1198 mini_rtc_ops = &starfire_rtc_ops;
1202 printk(KERN_INFO "Mini RTC Driver\n");
1204 retval = misc_register(&rtc_mini_dev);
1211 static void __exit rtc_mini_exit(void)
1213 misc_deregister(&rtc_mini_dev);
1216 int __devinit read_current_timer(unsigned long *timer_val)
1218 *timer_val = tick_ops->get_tick();
1222 module_init(rtc_mini_init);
1223 module_exit(rtc_mini_exit);