123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559560561562563564565566567568569570571572573574575576577578579580581582583584585586587588589590591592593594595596597598599600601602603604605606607608609610611612613614615616617618619620621622623624625626627628629630631632633634635636637638639640641642643644645646647648649650651652653654655656657658659660661662663664665666667668669670671672673674675676677678679680681682683684685686687688689690691692693694695696697698699700701702703704705706707708709710711712713714715716717718719720721722723724725726727728729 |
- /*
- * linux/arch/x86-64/kernel/time.c
- *
- * "High Precision Event Timer" based timekeeping.
- *
- * Copyright (c) 1991,1992,1995 Linus Torvalds
- * Copyright (c) 1994 Alan Modra
- * Copyright (c) 1995 Markus Kuhn
- * Copyright (c) 1996 Ingo Molnar
- * Copyright (c) 1998 Andrea Arcangeli
- * Copyright (c) 2002,2006 Vojtech Pavlik
- * Copyright (c) 2003 Andi Kleen
- * RTC support code taken from arch/i386/kernel/timers/time_hpet.c
- */
- #include <linux/kernel.h>
- #include <linux/sched.h>
- #include <linux/interrupt.h>
- #include <linux/init.h>
- #include <linux/mc146818rtc.h>
- #include <linux/time.h>
- #include <linux/ioport.h>
- #include <linux/module.h>
- #include <linux/device.h>
- #include <linux/sysdev.h>
- #include <linux/bcd.h>
- #include <linux/notifier.h>
- #include <linux/cpu.h>
- #include <linux/kallsyms.h>
- #include <linux/acpi.h>
- #ifdef CONFIG_ACPI
- #include <acpi/achware.h> /* for PM timer frequency */
- #include <acpi/acpi_bus.h>
- #endif
- #include <asm/8253pit.h>
- #include <asm/pgtable.h>
- #include <asm/vsyscall.h>
- #include <asm/timex.h>
- #include <asm/proto.h>
- #include <asm/hpet.h>
- #include <asm/sections.h>
- #include <linux/cpufreq.h>
- #include <linux/hpet.h>
- #include <asm/apic.h>
- #include <asm/hpet.h>
- #ifdef CONFIG_CPU_FREQ
- extern void cpufreq_delayed_get(void);
- #endif
- extern void i8254_timer_resume(void);
- extern int using_apic_timer;
- static char *timename = NULL;
- DEFINE_SPINLOCK(rtc_lock);
- EXPORT_SYMBOL(rtc_lock);
- DEFINE_SPINLOCK(i8253_lock);
- unsigned long vxtime_hz = PIT_TICK_RATE;
- int report_lost_ticks; /* command line option */
- unsigned long long monotonic_base;
- struct vxtime_data __vxtime __section_vxtime; /* for vsyscalls */
- volatile unsigned long __jiffies __section_jiffies = INITIAL_JIFFIES;
- struct timespec __xtime __section_xtime;
- struct timezone __sys_tz __section_sys_tz;
- unsigned int (*do_gettimeoffset)(void) = do_gettimeoffset_tsc;
- /*
- * This version of gettimeofday() has microsecond resolution and better than
- * microsecond precision, as we're using at least a 10 MHz (usually 14.31818
- * MHz) HPET timer.
- */
- void do_gettimeofday(struct timeval *tv)
- {
- unsigned long seq;
- unsigned int sec, usec;
- do {
- seq = read_seqbegin(&xtime_lock);
- sec = xtime.tv_sec;
- usec = xtime.tv_nsec / NSEC_PER_USEC;
- /* i386 does some correction here to keep the clock
- monotonous even when ntpd is fixing drift.
- But they didn't work for me, there is a non monotonic
- clock anyways with ntp.
- I dropped all corrections now until a real solution can
- be found. Note when you fix it here you need to do the same
- in arch/x86_64/kernel/vsyscall.c and export all needed
- variables in vmlinux.lds. -AK */
- usec += do_gettimeoffset();
- } while (read_seqretry(&xtime_lock, seq));
- tv->tv_sec = sec + usec / USEC_PER_SEC;
- tv->tv_usec = usec % USEC_PER_SEC;
- }
- EXPORT_SYMBOL(do_gettimeofday);
- /*
- * settimeofday() first undoes the correction that gettimeofday would do
- * on the time, and then saves it. This is ugly, but has been like this for
- * ages already.
- */
- int do_settimeofday(struct timespec *tv)
- {
- time_t wtm_sec, sec = tv->tv_sec;
- long wtm_nsec, nsec = tv->tv_nsec;
- if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC)
- return -EINVAL;
- write_seqlock_irq(&xtime_lock);
- nsec -= do_gettimeoffset() * NSEC_PER_USEC;
- wtm_sec = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec);
- wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec);
- set_normalized_timespec(&xtime, sec, nsec);
- set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec);
- ntp_clear();
- write_sequnlock_irq(&xtime_lock);
- clock_was_set();
- return 0;
- }
- EXPORT_SYMBOL(do_settimeofday);
- unsigned long profile_pc(struct pt_regs *regs)
- {
- unsigned long pc = instruction_pointer(regs);
- /* Assume the lock function has either no stack frame or a copy
- of eflags from PUSHF
- Eflags always has bits 22 and up cleared unlike kernel addresses. */
- if (!user_mode(regs) && in_lock_functions(pc)) {
- unsigned long *sp = (unsigned long *)regs->rsp;
- if (sp[0] >> 22)
- return sp[0];
- if (sp[1] >> 22)
- return sp[1];
- }
- return pc;
- }
- EXPORT_SYMBOL(profile_pc);
- /*
- * In order to set the CMOS clock precisely, set_rtc_mmss has to be called 500
- * ms after the second nowtime has started, because when nowtime is written
- * into the registers of the CMOS clock, it will jump to the next second
- * precisely 500 ms later. Check the Motorola MC146818A or Dallas DS12887 data
- * sheet for details.
- */
- static void set_rtc_mmss(unsigned long nowtime)
- {
- int real_seconds, real_minutes, cmos_minutes;
- unsigned char control, freq_select;
- /*
- * IRQs are disabled when we're called from the timer interrupt,
- * no need for spin_lock_irqsave()
- */
- spin_lock(&rtc_lock);
- /*
- * Tell the clock it's being set and stop it.
- */
- control = CMOS_READ(RTC_CONTROL);
- CMOS_WRITE(control | RTC_SET, RTC_CONTROL);
- freq_select = CMOS_READ(RTC_FREQ_SELECT);
- CMOS_WRITE(freq_select | RTC_DIV_RESET2, RTC_FREQ_SELECT);
- cmos_minutes = CMOS_READ(RTC_MINUTES);
- BCD_TO_BIN(cmos_minutes);
- /*
- * since we're only adjusting minutes and seconds, don't interfere with hour
- * overflow. This avoids messing with unknown time zones but requires your RTC
- * not to be off by more than 15 minutes. Since we're calling it only when
- * our clock is externally synchronized using NTP, this shouldn't be a problem.
- */
- real_seconds = nowtime % 60;
- real_minutes = nowtime / 60;
- if (((abs(real_minutes - cmos_minutes) + 15) / 30) & 1)
- real_minutes += 30; /* correct for half hour time zone */
- real_minutes %= 60;
- if (abs(real_minutes - cmos_minutes) >= 30) {
- printk(KERN_WARNING "time.c: can't update CMOS clock "
- "from %d to %d\n", cmos_minutes, real_minutes);
- } else {
- BIN_TO_BCD(real_seconds);
- BIN_TO_BCD(real_minutes);
- CMOS_WRITE(real_seconds, RTC_SECONDS);
- CMOS_WRITE(real_minutes, RTC_MINUTES);
- }
- /*
- * The following flags have to be released exactly in this order, otherwise the
- * DS12887 (popular MC146818A clone with integrated battery and quartz) will
- * not reset the oscillator and will not update precisely 500 ms later. You
- * won't find this mentioned in the Dallas Semiconductor data sheets, but who
- * believes data sheets anyway ... -- Markus Kuhn
- */
- CMOS_WRITE(control, RTC_CONTROL);
- CMOS_WRITE(freq_select, RTC_FREQ_SELECT);
- spin_unlock(&rtc_lock);
- }
- /* monotonic_clock(): returns # of nanoseconds passed since time_init()
- * Note: This function is required to return accurate
- * time even in the absence of multiple timer ticks.
- */
- extern unsigned long long cycles_2_ns(unsigned long long cyc);
- unsigned long long monotonic_clock(void)
- {
- unsigned long seq;
- u32 last_offset, this_offset, offset;
- unsigned long long base;
- if (vxtime.mode == VXTIME_HPET) {
- do {
- seq = read_seqbegin(&xtime_lock);
- last_offset = vxtime.last;
- base = monotonic_base;
- this_offset = hpet_readl(HPET_COUNTER);
- } while (read_seqretry(&xtime_lock, seq));
- offset = (this_offset - last_offset);
- offset *= NSEC_PER_TICK / hpet_tick;
- } else {
- do {
- seq = read_seqbegin(&xtime_lock);
- last_offset = vxtime.last_tsc;
- base = monotonic_base;
- } while (read_seqretry(&xtime_lock, seq));
- this_offset = get_cycles_sync();
- offset = cycles_2_ns(this_offset - last_offset);
- }
- return base + offset;
- }
- EXPORT_SYMBOL(monotonic_clock);
- static noinline void handle_lost_ticks(int lost)
- {
- static long lost_count;
- static int warned;
- if (report_lost_ticks) {
- printk(KERN_WARNING "time.c: Lost %d timer tick(s)! ", lost);
- print_symbol("rip %s)\n", get_irq_regs()->rip);
- }
- if (lost_count == 1000 && !warned) {
- printk(KERN_WARNING "warning: many lost ticks.\n"
- KERN_WARNING "Your time source seems to be instable or "
- "some driver is hogging interupts\n");
- print_symbol("rip %s\n", get_irq_regs()->rip);
- if (vxtime.mode == VXTIME_TSC && hpet_address) {
- printk(KERN_WARNING "Falling back to HPET\n");
- if (hpet_use_timer)
- vxtime.last = hpet_readl(HPET_T0_CMP) -
- hpet_tick;
- else
- vxtime.last = hpet_readl(HPET_COUNTER);
- vxtime.mode = VXTIME_HPET;
- vxtime.hpet_address = hpet_address;
- do_gettimeoffset = do_gettimeoffset_hpet;
- }
- /* else should fall back to PIT, but code missing. */
- warned = 1;
- } else
- lost_count++;
- #ifdef CONFIG_CPU_FREQ
- /* In some cases the CPU can change frequency without us noticing
- Give cpufreq a change to catch up. */
- if ((lost_count+1) % 25 == 0)
- cpufreq_delayed_get();
- #endif
- }
- void main_timer_handler(void)
- {
- static unsigned long rtc_update = 0;
- unsigned long tsc;
- int delay = 0, offset = 0, lost = 0;
- /*
- * Here we are in the timer irq handler. We have irqs locally disabled (so we
- * don't need spin_lock_irqsave()) but we don't know if the timer_bh is running
- * on the other CPU, so we need a lock. We also need to lock the vsyscall
- * variables, because both do_timer() and us change them -arca+vojtech
- */
- write_seqlock(&xtime_lock);
- if (hpet_address)
- offset = hpet_readl(HPET_COUNTER);
- if (hpet_use_timer) {
- /* if we're using the hpet timer functionality,
- * we can more accurately know the counter value
- * when the timer interrupt occured.
- */
- offset = hpet_readl(HPET_T0_CMP) - hpet_tick;
- delay = hpet_readl(HPET_COUNTER) - offset;
- } else if (!pmtmr_ioport) {
- spin_lock(&i8253_lock);
- outb_p(0x00, 0x43);
- delay = inb_p(0x40);
- delay |= inb(0x40) << 8;
- spin_unlock(&i8253_lock);
- delay = LATCH - 1 - delay;
- }
- tsc = get_cycles_sync();
- if (vxtime.mode == VXTIME_HPET) {
- if (offset - vxtime.last > hpet_tick) {
- lost = (offset - vxtime.last) / hpet_tick - 1;
- }
- monotonic_base +=
- (offset - vxtime.last) * NSEC_PER_TICK / hpet_tick;
- vxtime.last = offset;
- #ifdef CONFIG_X86_PM_TIMER
- } else if (vxtime.mode == VXTIME_PMTMR) {
- lost = pmtimer_mark_offset();
- #endif
- } else {
- offset = (((tsc - vxtime.last_tsc) *
- vxtime.tsc_quot) >> US_SCALE) - USEC_PER_TICK;
- if (offset < 0)
- offset = 0;
- if (offset > USEC_PER_TICK) {
- lost = offset / USEC_PER_TICK;
- offset %= USEC_PER_TICK;
- }
- monotonic_base += cycles_2_ns(tsc - vxtime.last_tsc);
- vxtime.last_tsc = tsc - vxtime.quot * delay / vxtime.tsc_quot;
- if ((((tsc - vxtime.last_tsc) *
- vxtime.tsc_quot) >> US_SCALE) < offset)
- vxtime.last_tsc = tsc -
- (((long) offset << US_SCALE) / vxtime.tsc_quot) - 1;
- }
- if (lost > 0)
- handle_lost_ticks(lost);
- else
- lost = 0;
- /*
- * Do the timer stuff.
- */
- do_timer(lost + 1);
- #ifndef CONFIG_SMP
- update_process_times(user_mode(get_irq_regs()));
- #endif
- /*
- * In the SMP case we use the local APIC timer interrupt to do the profiling,
- * except when we simulate SMP mode on a uniprocessor system, in that case we
- * have to call the local interrupt handler.
- */
- if (!using_apic_timer)
- smp_local_timer_interrupt();
- /*
- * If we have an externally synchronized Linux clock, then update CMOS clock
- * accordingly every ~11 minutes. set_rtc_mmss() will be called in the jiffy
- * closest to exactly 500 ms before the next second. If the update fails, we
- * don't care, as it'll be updated on the next turn, and the problem (time way
- * off) isn't likely to go away much sooner anyway.
- */
- if (ntp_synced() && xtime.tv_sec > rtc_update &&
- abs(xtime.tv_nsec - 500000000) <= tick_nsec / 2) {
- set_rtc_mmss(xtime.tv_sec);
- rtc_update = xtime.tv_sec + 660;
- }
-
- write_sequnlock(&xtime_lock);
- }
- static irqreturn_t timer_interrupt(int irq, void *dev_id)
- {
- if (apic_runs_main_timer > 1)
- return IRQ_HANDLED;
- main_timer_handler();
- if (using_apic_timer)
- smp_send_timer_broadcast_ipi();
- return IRQ_HANDLED;
- }
- static unsigned long get_cmos_time(void)
- {
- unsigned int year, mon, day, hour, min, sec;
- unsigned long flags;
- unsigned century = 0;
- spin_lock_irqsave(&rtc_lock, flags);
- do {
- sec = CMOS_READ(RTC_SECONDS);
- min = CMOS_READ(RTC_MINUTES);
- hour = CMOS_READ(RTC_HOURS);
- day = CMOS_READ(RTC_DAY_OF_MONTH);
- mon = CMOS_READ(RTC_MONTH);
- year = CMOS_READ(RTC_YEAR);
- #ifdef CONFIG_ACPI
- if (acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID &&
- acpi_gbl_FADT.century)
- century = CMOS_READ(acpi_gbl_FADT.century);
- #endif
- } while (sec != CMOS_READ(RTC_SECONDS));
- spin_unlock_irqrestore(&rtc_lock, flags);
- /*
- * We know that x86-64 always uses BCD format, no need to check the
- * config register.
- */
- BCD_TO_BIN(sec);
- BCD_TO_BIN(min);
- BCD_TO_BIN(hour);
- BCD_TO_BIN(day);
- BCD_TO_BIN(mon);
- BCD_TO_BIN(year);
- if (century) {
- BCD_TO_BIN(century);
- year += century * 100;
- printk(KERN_INFO "Extended CMOS year: %d\n", century * 100);
- } else {
- /*
- * x86-64 systems only exists since 2002.
- * This will work up to Dec 31, 2100
- */
- year += 2000;
- }
- return mktime(year, mon, day, hour, min, sec);
- }
- /*
- * pit_calibrate_tsc() uses the speaker output (channel 2) of
- * the PIT. This is better than using the timer interrupt output,
- * because we can read the value of the speaker with just one inb(),
- * where we need three i/o operations for the interrupt channel.
- * We count how many ticks the TSC does in 50 ms.
- */
- static unsigned int __init pit_calibrate_tsc(void)
- {
- unsigned long start, end;
- unsigned long flags;
- spin_lock_irqsave(&i8253_lock, flags);
- outb((inb(0x61) & ~0x02) | 0x01, 0x61);
- outb(0xb0, 0x43);
- outb((PIT_TICK_RATE / (1000 / 50)) & 0xff, 0x42);
- outb((PIT_TICK_RATE / (1000 / 50)) >> 8, 0x42);
- start = get_cycles_sync();
- while ((inb(0x61) & 0x20) == 0);
- end = get_cycles_sync();
- spin_unlock_irqrestore(&i8253_lock, flags);
-
- return (end - start) / 50;
- }
- #define PIT_MODE 0x43
- #define PIT_CH0 0x40
- static void __init __pit_init(int val, u8 mode)
- {
- unsigned long flags;
- spin_lock_irqsave(&i8253_lock, flags);
- outb_p(mode, PIT_MODE);
- outb_p(val & 0xff, PIT_CH0); /* LSB */
- outb_p(val >> 8, PIT_CH0); /* MSB */
- spin_unlock_irqrestore(&i8253_lock, flags);
- }
- void __init pit_init(void)
- {
- __pit_init(LATCH, 0x34); /* binary, mode 2, LSB/MSB, ch 0 */
- }
- void __init pit_stop_interrupt(void)
- {
- __pit_init(0, 0x30); /* mode 0 */
- }
- void __init stop_timer_interrupt(void)
- {
- char *name;
- if (hpet_address) {
- name = "HPET";
- hpet_timer_stop_set_go(0);
- } else {
- name = "PIT";
- pit_stop_interrupt();
- }
- printk(KERN_INFO "timer: %s interrupt stopped.\n", name);
- }
- int __init time_setup(char *str)
- {
- report_lost_ticks = 1;
- return 1;
- }
- static struct irqaction irq0 = {
- timer_interrupt, IRQF_DISABLED, CPU_MASK_NONE, "timer", NULL, NULL
- };
- void __init time_init(void)
- {
- if (nohpet)
- hpet_address = 0;
- xtime.tv_sec = get_cmos_time();
- xtime.tv_nsec = 0;
- set_normalized_timespec(&wall_to_monotonic,
- -xtime.tv_sec, -xtime.tv_nsec);
- if (!hpet_arch_init())
- vxtime_hz = (FSEC_PER_SEC + hpet_period / 2) / hpet_period;
- else
- hpet_address = 0;
- if (hpet_use_timer) {
- /* set tick_nsec to use the proper rate for HPET */
- tick_nsec = TICK_NSEC_HPET;
- cpu_khz = hpet_calibrate_tsc();
- timename = "HPET";
- #ifdef CONFIG_X86_PM_TIMER
- } else if (pmtmr_ioport && !hpet_address) {
- vxtime_hz = PM_TIMER_FREQUENCY;
- timename = "PM";
- pit_init();
- cpu_khz = pit_calibrate_tsc();
- #endif
- } else {
- pit_init();
- cpu_khz = pit_calibrate_tsc();
- timename = "PIT";
- }
- vxtime.mode = VXTIME_TSC;
- vxtime.quot = (USEC_PER_SEC << US_SCALE) / vxtime_hz;
- vxtime.tsc_quot = (USEC_PER_MSEC << US_SCALE) / cpu_khz;
- vxtime.last_tsc = get_cycles_sync();
- set_cyc2ns_scale(cpu_khz);
- setup_irq(0, &irq0);
- #ifndef CONFIG_SMP
- time_init_gtod();
- #endif
- }
- /*
- * Decide what mode gettimeofday should use.
- */
- void time_init_gtod(void)
- {
- char *timetype;
- if (unsynchronized_tsc())
- notsc = 1;
- if (cpu_has(&boot_cpu_data, X86_FEATURE_RDTSCP))
- vgetcpu_mode = VGETCPU_RDTSCP;
- else
- vgetcpu_mode = VGETCPU_LSL;
- if (hpet_address && notsc) {
- timetype = hpet_use_timer ? "HPET" : "PIT/HPET";
- if (hpet_use_timer)
- vxtime.last = hpet_readl(HPET_T0_CMP) - hpet_tick;
- else
- vxtime.last = hpet_readl(HPET_COUNTER);
- vxtime.mode = VXTIME_HPET;
- vxtime.hpet_address = hpet_address;
- do_gettimeoffset = do_gettimeoffset_hpet;
- #ifdef CONFIG_X86_PM_TIMER
- /* Using PM for gettimeofday is quite slow, but we have no other
- choice because the TSC is too unreliable on some systems. */
- } else if (pmtmr_ioport && !hpet_address && notsc) {
- timetype = "PM";
- do_gettimeoffset = do_gettimeoffset_pm;
- vxtime.mode = VXTIME_PMTMR;
- sysctl_vsyscall = 0;
- printk(KERN_INFO "Disabling vsyscall due to use of PM timer\n");
- #endif
- } else {
- timetype = hpet_use_timer ? "HPET/TSC" : "PIT/TSC";
- vxtime.mode = VXTIME_TSC;
- }
- printk(KERN_INFO "time.c: Using %ld.%06ld MHz WALL %s GTOD %s timer.\n",
- vxtime_hz / 1000000, vxtime_hz % 1000000, timename, timetype);
- printk(KERN_INFO "time.c: Detected %d.%03d MHz processor.\n",
- cpu_khz / 1000, cpu_khz % 1000);
- vxtime.quot = (USEC_PER_SEC << US_SCALE) / vxtime_hz;
- vxtime.tsc_quot = (USEC_PER_MSEC << US_SCALE) / cpu_khz;
- vxtime.last_tsc = get_cycles_sync();
- set_cyc2ns_scale(cpu_khz);
- }
- __setup("report_lost_ticks", time_setup);
- static long clock_cmos_diff;
- static unsigned long sleep_start;
- /*
- * sysfs support for the timer.
- */
- static int timer_suspend(struct sys_device *dev, pm_message_t state)
- {
- /*
- * Estimate time zone so that set_time can update the clock
- */
- long cmos_time = get_cmos_time();
- clock_cmos_diff = -cmos_time;
- clock_cmos_diff += get_seconds();
- sleep_start = cmos_time;
- return 0;
- }
- static int timer_resume(struct sys_device *dev)
- {
- unsigned long flags;
- unsigned long sec;
- unsigned long ctime = get_cmos_time();
- long sleep_length = (ctime - sleep_start) * HZ;
- if (sleep_length < 0) {
- printk(KERN_WARNING "Time skew detected in timer resume!\n");
- /* The time after the resume must not be earlier than the time
- * before the suspend or some nasty things will happen
- */
- sleep_length = 0;
- ctime = sleep_start;
- }
- if (hpet_address)
- hpet_reenable();
- else
- i8254_timer_resume();
- sec = ctime + clock_cmos_diff;
- write_seqlock_irqsave(&xtime_lock,flags);
- xtime.tv_sec = sec;
- xtime.tv_nsec = 0;
- if (vxtime.mode == VXTIME_HPET) {
- if (hpet_use_timer)
- vxtime.last = hpet_readl(HPET_T0_CMP) - hpet_tick;
- else
- vxtime.last = hpet_readl(HPET_COUNTER);
- #ifdef CONFIG_X86_PM_TIMER
- } else if (vxtime.mode == VXTIME_PMTMR) {
- pmtimer_resume();
- #endif
- } else
- vxtime.last_tsc = get_cycles_sync();
- write_sequnlock_irqrestore(&xtime_lock,flags);
- jiffies += sleep_length;
- monotonic_base += sleep_length * (NSEC_PER_SEC/HZ);
- touch_softlockup_watchdog();
- return 0;
- }
- static struct sysdev_class timer_sysclass = {
- .resume = timer_resume,
- .suspend = timer_suspend,
- set_kset_name("timer"),
- };
- /* XXX this driverfs stuff should probably go elsewhere later -john */
- static struct sys_device device_timer = {
- .id = 0,
- .cls = &timer_sysclass,
- };
- static int time_init_device(void)
- {
- int error = sysdev_class_register(&timer_sysclass);
- if (!error)
- error = sysdev_register(&device_timer);
- return error;
- }
- device_initcall(time_init_device);
|