X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=kernel%2Ftime%2Fntp.c;h=e64efaf957e8485b4d233412a69fdf45a1225691;hb=cc584b213f252bf698849cf4be2377cd3ec7501a;hp=438c6b723ee202bd3a22607f2ebf7d4b031d1f6b;hpb=e245befce7af0a1e1347079ed62695b059594bd4;p=linux-2.6-omap-h63xx.git diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c index 438c6b723ee..4c8d85421d2 100644 --- a/kernel/time/ntp.c +++ b/kernel/time/ntp.c @@ -10,11 +10,13 @@ #include #include +#include #include #include #include #include -#include +#include +#include #include /* @@ -22,11 +24,14 @@ */ unsigned long tick_usec = TICK_USEC; /* USER_HZ period (usec) */ unsigned long tick_nsec; /* ACTHZ period (nsec) */ -static u64 tick_length, tick_length_base; +u64 tick_length; +static u64 tick_length_base; + +static struct hrtimer leap_timer; #define MAX_TICKADJ 500 /* microsecs */ #define MAX_TICKADJ_SCALED (((u64)(MAX_TICKADJ * NSEC_PER_USEC) << \ - TICK_LENGTH_SHIFT) / NTP_INTERVAL_FREQ) + NTP_SCALE_SHIFT) / NTP_INTERVAL_FREQ) /* * phase-lock loop variables @@ -34,31 +39,69 @@ static u64 tick_length, tick_length_base; /* TIME_ERROR prevents overwriting the CMOS clock */ static int time_state = TIME_OK; /* clock synchronization status */ int time_status = STA_UNSYNC; /* clock status bits */ -static s64 time_offset; /* time adjustment (ns) */ +static long time_tai; /* TAI offset (s) */ +static s64 time_offset; /* time adjustment (ns) */ static long time_constant = 2; /* pll time constant */ long time_maxerror = NTP_PHASE_LIMIT; /* maximum error (us) */ long time_esterror = NTP_PHASE_LIMIT; /* estimated error (us) */ -long time_freq; /* frequency offset (scaled ppm)*/ +static s64 time_freq; /* frequency offset (scaled ns/s)*/ static long time_reftime; /* time at last adjustment (s) */ long time_adjust; - -#define CLOCK_TICK_OVERFLOW (LATCH * HZ - CLOCK_TICK_RATE) -#define CLOCK_TICK_ADJUST (((s64)CLOCK_TICK_OVERFLOW * NSEC_PER_SEC) / \ - (s64)CLOCK_TICK_RATE) +static long ntp_tick_adj; static void ntp_update_frequency(void) { u64 second_length = (u64)(tick_usec * NSEC_PER_USEC * USER_HZ) - << TICK_LENGTH_SHIFT; - second_length += (s64)CLOCK_TICK_ADJUST << TICK_LENGTH_SHIFT; - second_length += (s64)time_freq << (TICK_LENGTH_SHIFT - SHIFT_NSEC); + << NTP_SCALE_SHIFT; + second_length += (s64)ntp_tick_adj << NTP_SCALE_SHIFT; + second_length += time_freq; tick_length_base = second_length; - do_div(second_length, HZ); - tick_nsec = second_length >> TICK_LENGTH_SHIFT; + tick_nsec = div_u64(second_length, HZ) >> NTP_SCALE_SHIFT; + tick_length_base = div_u64(tick_length_base, NTP_INTERVAL_FREQ); +} + +static void ntp_update_offset(long offset) +{ + long mtemp; + s64 freq_adj; + + if (!(time_status & STA_PLL)) + return; + + if (!(time_status & STA_NANO)) + offset *= NSEC_PER_USEC; - do_div(tick_length_base, NTP_INTERVAL_FREQ); + /* + * Scale the phase adjustment and + * clamp to the operating range. + */ + offset = min(offset, MAXPHASE); + offset = max(offset, -MAXPHASE); + + /* + * Select how the frequency is to be controlled + * and in which mode (PLL or FLL). + */ + if (time_status & STA_FREQHOLD || time_reftime == 0) + time_reftime = xtime.tv_sec; + mtemp = xtime.tv_sec - time_reftime; + time_reftime = xtime.tv_sec; + + freq_adj = (s64)offset * mtemp; + freq_adj <<= NTP_SCALE_SHIFT - 2 * (SHIFT_PLL + 2 + time_constant); + time_status &= ~STA_MODE; + if (mtemp >= MINSEC && (time_status & STA_FLL || mtemp > MAXSEC)) { + freq_adj += div_s64((s64)offset << (NTP_SCALE_SHIFT - SHIFT_FLL), + mtemp); + time_status |= STA_MODE; + } + freq_adj += time_freq; + freq_adj = min(freq_adj, MAXFREQ_SCALED); + time_freq = max(freq_adj, -MAXFREQ_SCALED); + + time_offset = div_s64((s64)offset << NTP_SCALE_SHIFT, NTP_INTERVAL_FREQ); } /** @@ -80,72 +123,69 @@ void ntp_clear(void) } /* - * this routine handles the overflow of the microsecond field - * - * The tricky bits of code to handle the accurate clock support - * were provided by Dave Mills (Mills@UDEL.EDU) of NTP fame. - * They were originally developed for SUN and DEC kernels. - * All the kudos should go to Dave for this stuff. + * Leap second processing. If in leap-insert state at the end of the + * day, the system clock is set back one second; if in leap-delete + * state, the system clock is set ahead one second. */ -void second_overflow(void) +static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer) { - long time_adj; + enum hrtimer_restart res = HRTIMER_NORESTART; - /* Bump the maxerror field */ - time_maxerror += MAXFREQ >> SHIFT_USEC; - if (time_maxerror > NTP_PHASE_LIMIT) { - time_maxerror = NTP_PHASE_LIMIT; - time_status |= STA_UNSYNC; - } + write_seqlock_irq(&xtime_lock); - /* - * Leap second processing. If in leap-insert state at the end of the - * day, the system clock is set back one second; if in leap-delete - * state, the system clock is set ahead one second. The microtime() - * routine or external clock driver will insure that reported time is - * always monotonic. The ugly divides should be replaced. - */ switch (time_state) { case TIME_OK: - if (time_status & STA_INS) - time_state = TIME_INS; - else if (time_status & STA_DEL) - time_state = TIME_DEL; break; case TIME_INS: - if (xtime.tv_sec % 86400 == 0) { - xtime.tv_sec--; - wall_to_monotonic.tv_sec++; - /* - * The timer interpolator will make time change - * gradually instead of an immediate jump by one second - */ - time_interpolator_update(-NSEC_PER_SEC); - time_state = TIME_OOP; - printk(KERN_NOTICE "Clock: inserting leap second " - "23:59:60 UTC\n"); - } + xtime.tv_sec--; + wall_to_monotonic.tv_sec++; + time_state = TIME_OOP; + printk(KERN_NOTICE "Clock: " + "inserting leap second 23:59:60 UTC\n"); + hrtimer_add_expires_ns(&leap_timer, NSEC_PER_SEC); + res = HRTIMER_RESTART; break; case TIME_DEL: - if ((xtime.tv_sec + 1) % 86400 == 0) { - xtime.tv_sec++; - wall_to_monotonic.tv_sec--; - /* - * Use of time interpolator for a gradual change of - * time - */ - time_interpolator_update(NSEC_PER_SEC); - time_state = TIME_WAIT; - printk(KERN_NOTICE "Clock: deleting leap second " - "23:59:59 UTC\n"); - } + xtime.tv_sec++; + time_tai--; + wall_to_monotonic.tv_sec--; + time_state = TIME_WAIT; + printk(KERN_NOTICE "Clock: " + "deleting leap second 23:59:59 UTC\n"); break; case TIME_OOP: + time_tai++; time_state = TIME_WAIT; - break; + /* fall through */ case TIME_WAIT: if (!(time_status & (STA_INS | STA_DEL))) - time_state = TIME_OK; + time_state = TIME_OK; + break; + } + update_vsyscall(&xtime, clock); + + write_sequnlock_irq(&xtime_lock); + + return res; +} + +/* + * this routine handles the overflow of the microsecond field + * + * The tricky bits of code to handle the accurate clock support + * were provided by Dave Mills (Mills@UDEL.EDU) of NTP fame. + * They were originally developed for SUN and DEC kernels. + * All the kudos should go to Dave for this stuff. + */ +void second_overflow(void) +{ + s64 time_adj; + + /* Bump the maxerror field */ + time_maxerror += MAXFREQ / NSEC_PER_USEC; + if (time_maxerror > NTP_PHASE_LIMIT) { + time_maxerror = NTP_PHASE_LIMIT; + time_status |= STA_UNSYNC; } /* @@ -155,7 +195,7 @@ void second_overflow(void) tick_length = tick_length_base; time_adj = shift_right(time_offset, SHIFT_PLL + time_constant); time_offset -= time_adj; - tick_length += (s64)time_adj << (TICK_LENGTH_SHIFT - SHIFT_UPDATE); + tick_length += time_adj; if (unlikely(time_adjust)) { if (time_adjust > MAX_TICKADJ) { @@ -166,38 +206,77 @@ void second_overflow(void) tick_length -= MAX_TICKADJ_SCALED; } else { tick_length += (s64)(time_adjust * NSEC_PER_USEC / - NTP_INTERVAL_FREQ) << TICK_LENGTH_SHIFT; + NTP_INTERVAL_FREQ) << NTP_SCALE_SHIFT; time_adjust = 0; } } } -/* - * Return how long ticks are at the moment, that is, how much time - * update_wall_time_one_tick will add to xtime next time we call it - * (assuming no calls to do_adjtimex in the meantime). - * The return value is in fixed-point nanoseconds shifted by the - * specified number of bits to the right of the binary point. - * This function has no side-effects. - */ -u64 current_tick_length(void) +#ifdef CONFIG_GENERIC_CMOS_UPDATE + +/* Disable the cmos update - used by virtualization and embedded */ +int no_sync_cmos_clock __read_mostly; + +static void sync_cmos_clock(unsigned long dummy); + +static DEFINE_TIMER(sync_cmos_timer, sync_cmos_clock, 0, 0); + +static void sync_cmos_clock(unsigned long dummy) { - return tick_length; -} + struct timespec now, next; + int fail = 1; + /* + * If we have an externally synchronized Linux clock, then update + * CMOS clock accordingly every ~11 minutes. Set_rtc_mmss() has to be + * called as close as possible to 500 ms before the new second starts. + * This code is run on a timer. If the clock is set, that timer + * may not expire at the correct time. Thus, we adjust... + */ + if (!ntp_synced()) + /* + * Not synced, exit, do not restart a timer (if one is + * running, let it run out). + */ + return; + + getnstimeofday(&now); + if (abs(now.tv_nsec - (NSEC_PER_SEC / 2)) <= tick_nsec / 2) + fail = update_persistent_clock(now); + + next.tv_nsec = (NSEC_PER_SEC / 2) - now.tv_nsec; + if (next.tv_nsec <= 0) + next.tv_nsec += NSEC_PER_SEC; + + if (!fail) + next.tv_sec = 659; + else + next.tv_sec = 0; + + if (next.tv_nsec >= NSEC_PER_SEC) { + next.tv_sec++; + next.tv_nsec -= NSEC_PER_SEC; + } + mod_timer(&sync_cmos_timer, jiffies + timespec_to_jiffies(&next)); +} -void __attribute__ ((weak)) notify_arch_cmos_timer(void) +static void notify_cmos_timer(void) { - return; + if (!no_sync_cmos_clock) + mod_timer(&sync_cmos_timer, jiffies + 1); } +#else +static inline void notify_cmos_timer(void) { } +#endif + /* adjtimex mainly allows reading (and writing, if superuser) of * kernel time-keeping variables. used by xntpd. */ int do_adjtimex(struct timex *txc) { - long mtemp, save_adjust, rem; - s64 freq_adj, temp64; + struct timespec ts; + long save_adjust, sec; int result; /* In order to modify anything, you gotta be super-user! */ @@ -206,15 +285,11 @@ int do_adjtimex(struct timex *txc) /* Now we validate the data before disabling interrupts */ - if ((txc->modes & ADJ_OFFSET_SINGLESHOT) == ADJ_OFFSET_SINGLESHOT) - /* singleshot must not be used with any other mode bits */ - if (txc->modes != ADJ_OFFSET_SINGLESHOT) - return -EINVAL; - - if (txc->modes != ADJ_OFFSET_SINGLESHOT && (txc->modes & ADJ_OFFSET)) - /* adjustment Offset limited to +- .512 seconds */ - if (txc->offset <= - MAXPHASE || txc->offset >= MAXPHASE ) + if ((txc->modes & ADJ_OFFSET_SINGLESHOT) == ADJ_OFFSET_SINGLESHOT) { + /* singleshot must not be used with any other mode bits */ + if (txc->modes & ~ADJ_OFFSET_SS_READ) return -EINVAL; + } /* if the quartz is off by more than 10% something is VERY wrong ! */ if (txc->modes & ADJ_TICK) @@ -222,127 +297,121 @@ int do_adjtimex(struct timex *txc) txc->tick > 1100000/USER_HZ) return -EINVAL; + if (time_state != TIME_OK && txc->modes & ADJ_STATUS) + hrtimer_cancel(&leap_timer); + getnstimeofday(&ts); + write_seqlock_irq(&xtime_lock); - result = time_state; /* mostly `TIME_OK' */ /* Save for later - semantics of adjtime is to return old value */ save_adjust = time_adjust; -#if 0 /* STA_CLOCKERR is never set yet */ - time_status &= ~STA_CLOCKERR; /* reset STA_CLOCKERR */ -#endif /* If there are input parameters, then process them */ - if (txc->modes) - { - if (txc->modes & ADJ_STATUS) /* only set allowed bits */ - time_status = (txc->status & ~STA_RONLY) | - (time_status & STA_RONLY); - - if (txc->modes & ADJ_FREQUENCY) { /* p. 22 */ - if (txc->freq > MAXFREQ || txc->freq < -MAXFREQ) { - result = -EINVAL; - goto leave; - } - time_freq = ((s64)txc->freq * NSEC_PER_USEC) - >> (SHIFT_USEC - SHIFT_NSEC); - } - - if (txc->modes & ADJ_MAXERROR) { - if (txc->maxerror < 0 || txc->maxerror >= NTP_PHASE_LIMIT) { - result = -EINVAL; - goto leave; + if (txc->modes) { + if (txc->modes & ADJ_STATUS) { + if ((time_status & STA_PLL) && + !(txc->status & STA_PLL)) { + time_state = TIME_OK; + time_status = STA_UNSYNC; + } + /* only set allowed bits */ + time_status &= STA_RONLY; + time_status |= txc->status & ~STA_RONLY; + + switch (time_state) { + case TIME_OK: + start_timer: + sec = ts.tv_sec; + if (time_status & STA_INS) { + time_state = TIME_INS; + sec += 86400 - sec % 86400; + hrtimer_start(&leap_timer, ktime_set(sec, 0), HRTIMER_MODE_ABS); + } else if (time_status & STA_DEL) { + time_state = TIME_DEL; + sec += 86400 - (sec + 1) % 86400; + hrtimer_start(&leap_timer, ktime_set(sec, 0), HRTIMER_MODE_ABS); + } + break; + case TIME_INS: + case TIME_DEL: + time_state = TIME_OK; + goto start_timer; + break; + case TIME_WAIT: + if (!(time_status & (STA_INS | STA_DEL))) + time_state = TIME_OK; + break; + case TIME_OOP: + hrtimer_restart(&leap_timer); + break; + } } - time_maxerror = txc->maxerror; - } - if (txc->modes & ADJ_ESTERROR) { - if (txc->esterror < 0 || txc->esterror >= NTP_PHASE_LIMIT) { - result = -EINVAL; - goto leave; + if (txc->modes & ADJ_NANO) + time_status |= STA_NANO; + if (txc->modes & ADJ_MICRO) + time_status &= ~STA_NANO; + + if (txc->modes & ADJ_FREQUENCY) { + time_freq = (s64)txc->freq * PPM_SCALE; + time_freq = min(time_freq, MAXFREQ_SCALED); + time_freq = max(time_freq, -MAXFREQ_SCALED); } - time_esterror = txc->esterror; - } - if (txc->modes & ADJ_TIMECONST) { /* p. 24 */ - if (txc->constant < 0) { /* NTP v4 uses values > 6 */ - result = -EINVAL; - goto leave; + if (txc->modes & ADJ_MAXERROR) + time_maxerror = txc->maxerror; + if (txc->modes & ADJ_ESTERROR) + time_esterror = txc->esterror; + + if (txc->modes & ADJ_TIMECONST) { + time_constant = txc->constant; + if (!(time_status & STA_NANO)) + time_constant += 4; + time_constant = min(time_constant, (long)MAXTC); + time_constant = max(time_constant, 0l); } - time_constant = min(txc->constant + 4, (long)MAXTC); - } - if (txc->modes & ADJ_OFFSET) { /* values checked earlier */ - if (txc->modes == ADJ_OFFSET_SINGLESHOT) { - /* adjtime() is independent from ntp_adjtime() */ - time_adjust = txc->offset; + if (txc->modes & ADJ_TAI && txc->constant > 0) + time_tai = txc->constant; + + if (txc->modes & ADJ_OFFSET) { + if (txc->modes == ADJ_OFFSET_SINGLESHOT) + /* adjtime() is independent from ntp_adjtime() */ + time_adjust = txc->offset; + else + ntp_update_offset(txc->offset); } - else if (time_status & STA_PLL) { - time_offset = txc->offset * NSEC_PER_USEC; - - /* - * Scale the phase adjustment and - * clamp to the operating range. - */ - time_offset = min(time_offset, (s64)MAXPHASE * NSEC_PER_USEC); - time_offset = max(time_offset, (s64)-MAXPHASE * NSEC_PER_USEC); - - /* - * Select whether the frequency is to be controlled - * and in which mode (PLL or FLL). Clamp to the operating - * range. Ugly multiply/divide should be replaced someday. - */ - - if (time_status & STA_FREQHOLD || time_reftime == 0) - time_reftime = xtime.tv_sec; - mtemp = xtime.tv_sec - time_reftime; - time_reftime = xtime.tv_sec; - - freq_adj = time_offset * mtemp; - freq_adj = shift_right(freq_adj, time_constant * 2 + - (SHIFT_PLL + 2) * 2 - SHIFT_NSEC); - if (mtemp >= MINSEC && (time_status & STA_FLL || mtemp > MAXSEC)) { - temp64 = time_offset << (SHIFT_NSEC - SHIFT_FLL); - if (time_offset < 0) { - temp64 = -temp64; - do_div(temp64, mtemp); - freq_adj -= temp64; - } else { - do_div(temp64, mtemp); - freq_adj += temp64; - } - } - freq_adj += time_freq; - freq_adj = min(freq_adj, (s64)MAXFREQ_NSEC); - time_freq = max(freq_adj, (s64)-MAXFREQ_NSEC); - time_offset = div_long_long_rem_signed(time_offset, - NTP_INTERVAL_FREQ, - &rem); - time_offset <<= SHIFT_UPDATE; - } /* STA_PLL */ - } /* txc->modes & ADJ_OFFSET */ - if (txc->modes & ADJ_TICK) - tick_usec = txc->tick; - - if (txc->modes & (ADJ_TICK|ADJ_FREQUENCY|ADJ_OFFSET)) - ntp_update_frequency(); - } /* txc->modes */ -leave: if ((time_status & (STA_UNSYNC|STA_CLOCKERR)) != 0) + if (txc->modes & ADJ_TICK) + tick_usec = txc->tick; + + if (txc->modes & (ADJ_TICK|ADJ_FREQUENCY|ADJ_OFFSET)) + ntp_update_frequency(); + } + + result = time_state; /* mostly `TIME_OK' */ + if (time_status & (STA_UNSYNC|STA_CLOCKERR)) result = TIME_ERROR; - if ((txc->modes & ADJ_OFFSET_SINGLESHOT) == ADJ_OFFSET_SINGLESHOT) + if ((txc->modes == ADJ_OFFSET_SINGLESHOT) || + (txc->modes == ADJ_OFFSET_SS_READ)) txc->offset = save_adjust; - else - txc->offset = ((long)shift_right(time_offset, SHIFT_UPDATE)) * - NTP_INTERVAL_FREQ / 1000; - txc->freq = (time_freq / NSEC_PER_USEC) << - (SHIFT_USEC - SHIFT_NSEC); + else { + txc->offset = shift_right(time_offset * NTP_INTERVAL_FREQ, + NTP_SCALE_SHIFT); + if (!(time_status & STA_NANO)) + txc->offset /= NSEC_PER_USEC; + } + txc->freq = shift_right((s32)(time_freq >> PPM_SCALE_INV_SHIFT) * + (s64)PPM_SCALE_INV, + NTP_SCALE_SHIFT); txc->maxerror = time_maxerror; txc->esterror = time_esterror; txc->status = time_status; txc->constant = time_constant; txc->precision = 1; - txc->tolerance = MAXFREQ; + txc->tolerance = MAXFREQ_SCALED / PPM_SCALE; txc->tick = tick_usec; + txc->tai = time_tai; /* PPS is not implemented, so these are zero */ txc->ppsfreq = 0; @@ -354,7 +423,28 @@ leave: if ((time_status & (STA_UNSYNC|STA_CLOCKERR)) != 0) txc->errcnt = 0; txc->stbcnt = 0; write_sequnlock_irq(&xtime_lock); - do_gettimeofday(&txc->time); - notify_arch_cmos_timer(); - return(result); + + txc->time.tv_sec = ts.tv_sec; + txc->time.tv_usec = ts.tv_nsec; + if (!(time_status & STA_NANO)) + txc->time.tv_usec /= NSEC_PER_USEC; + + notify_cmos_timer(); + + return result; +} + +static int __init ntp_tick_adj_setup(char *str) +{ + ntp_tick_adj = simple_strtol(str, NULL, 0); + return 1; +} + +__setup("ntp_tick_adj=", ntp_tick_adj_setup); + +void __init ntp_init(void) +{ + ntp_clear(); + hrtimer_init(&leap_timer, CLOCK_REALTIME, HRTIMER_MODE_ABS); + leap_timer.function = ntp_leap_second; }