ntp.c (f43dc23d5ea91fca257be02138a255f02d98e806) | ntp.c (025b40abe715d638e60516a657d354e8560c1a85) |
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1/* 2 * NTP state machine interfaces and logic. 3 * 4 * This code was mainly moved from kernel/timer.c and kernel/time.c 5 * Please see those files for relevant copyright info and historical 6 * changelogs. 7 */ 8#include <linux/capability.h> 9#include <linux/clocksource.h> 10#include <linux/workqueue.h> 11#include <linux/hrtimer.h> 12#include <linux/jiffies.h> 13#include <linux/math64.h> 14#include <linux/timex.h> 15#include <linux/time.h> 16#include <linux/mm.h> | 1/* 2 * NTP state machine interfaces and logic. 3 * 4 * This code was mainly moved from kernel/timer.c and kernel/time.c 5 * Please see those files for relevant copyright info and historical 6 * changelogs. 7 */ 8#include <linux/capability.h> 9#include <linux/clocksource.h> 10#include <linux/workqueue.h> 11#include <linux/hrtimer.h> 12#include <linux/jiffies.h> 13#include <linux/math64.h> 14#include <linux/timex.h> 15#include <linux/time.h> 16#include <linux/mm.h> |
17#include <linux/module.h> |
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17 18/* 19 * NTP timekeeping variables: 20 */ 21 22/* USER_HZ period (usecs): */ 23unsigned long tick_usec = TICK_USEC; 24 --- 44 unchanged lines hidden (view full) --- 69/* time at last adjustment (secs): */ 70static long time_reftime; 71 72static long time_adjust; 73 74/* constant (boot-param configurable) NTP tick adjustment (upscaled) */ 75static s64 ntp_tick_adj; 76 | 18 19/* 20 * NTP timekeeping variables: 21 */ 22 23/* USER_HZ period (usecs): */ 24unsigned long tick_usec = TICK_USEC; 25 --- 44 unchanged lines hidden (view full) --- 70/* time at last adjustment (secs): */ 71static long time_reftime; 72 73static long time_adjust; 74 75/* constant (boot-param configurable) NTP tick adjustment (upscaled) */ 76static s64 ntp_tick_adj; 77 |
78#ifdef CONFIG_NTP_PPS 79 |
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77/* | 80/* |
81 * The following variables are used when a pulse-per-second (PPS) signal 82 * is available. They establish the engineering parameters of the clock 83 * discipline loop when controlled by the PPS signal. 84 */ 85#define PPS_VALID 10 /* PPS signal watchdog max (s) */ 86#define PPS_POPCORN 4 /* popcorn spike threshold (shift) */ 87#define PPS_INTMIN 2 /* min freq interval (s) (shift) */ 88#define PPS_INTMAX 8 /* max freq interval (s) (shift) */ 89#define PPS_INTCOUNT 4 /* number of consecutive good intervals to 90 increase pps_shift or consecutive bad 91 intervals to decrease it */ 92#define PPS_MAXWANDER 100000 /* max PPS freq wander (ns/s) */ 93 94static int pps_valid; /* signal watchdog counter */ 95static long pps_tf[3]; /* phase median filter */ 96static long pps_jitter; /* current jitter (ns) */ 97static struct timespec pps_fbase; /* beginning of the last freq interval */ 98static int pps_shift; /* current interval duration (s) (shift) */ 99static int pps_intcnt; /* interval counter */ 100static s64 pps_freq; /* frequency offset (scaled ns/s) */ 101static long pps_stabil; /* current stability (scaled ns/s) */ 102 103/* 104 * PPS signal quality monitors 105 */ 106static long pps_calcnt; /* calibration intervals */ 107static long pps_jitcnt; /* jitter limit exceeded */ 108static long pps_stbcnt; /* stability limit exceeded */ 109static long pps_errcnt; /* calibration errors */ 110 111 112/* PPS kernel consumer compensates the whole phase error immediately. 113 * Otherwise, reduce the offset by a fixed factor times the time constant. 114 */ 115static inline s64 ntp_offset_chunk(s64 offset) 116{ 117 if (time_status & STA_PPSTIME && time_status & STA_PPSSIGNAL) 118 return offset; 119 else 120 return shift_right(offset, SHIFT_PLL + time_constant); 121} 122 123static inline void pps_reset_freq_interval(void) 124{ 125 /* the PPS calibration interval may end 126 surprisingly early */ 127 pps_shift = PPS_INTMIN; 128 pps_intcnt = 0; 129} 130 131/** 132 * pps_clear - Clears the PPS state variables 133 * 134 * Must be called while holding a write on the xtime_lock 135 */ 136static inline void pps_clear(void) 137{ 138 pps_reset_freq_interval(); 139 pps_tf[0] = 0; 140 pps_tf[1] = 0; 141 pps_tf[2] = 0; 142 pps_fbase.tv_sec = pps_fbase.tv_nsec = 0; 143 pps_freq = 0; 144} 145 146/* Decrease pps_valid to indicate that another second has passed since 147 * the last PPS signal. When it reaches 0, indicate that PPS signal is 148 * missing. 149 * 150 * Must be called while holding a write on the xtime_lock 151 */ 152static inline void pps_dec_valid(void) 153{ 154 if (pps_valid > 0) 155 pps_valid--; 156 else { 157 time_status &= ~(STA_PPSSIGNAL | STA_PPSJITTER | 158 STA_PPSWANDER | STA_PPSERROR); 159 pps_clear(); 160 } 161} 162 163static inline void pps_set_freq(s64 freq) 164{ 165 pps_freq = freq; 166} 167 168static inline int is_error_status(int status) 169{ 170 return (time_status & (STA_UNSYNC|STA_CLOCKERR)) 171 /* PPS signal lost when either PPS time or 172 * PPS frequency synchronization requested 173 */ 174 || ((time_status & (STA_PPSFREQ|STA_PPSTIME)) 175 && !(time_status & STA_PPSSIGNAL)) 176 /* PPS jitter exceeded when 177 * PPS time synchronization requested */ 178 || ((time_status & (STA_PPSTIME|STA_PPSJITTER)) 179 == (STA_PPSTIME|STA_PPSJITTER)) 180 /* PPS wander exceeded or calibration error when 181 * PPS frequency synchronization requested 182 */ 183 || ((time_status & STA_PPSFREQ) 184 && (time_status & (STA_PPSWANDER|STA_PPSERROR))); 185} 186 187static inline void pps_fill_timex(struct timex *txc) 188{ 189 txc->ppsfreq = shift_right((pps_freq >> PPM_SCALE_INV_SHIFT) * 190 PPM_SCALE_INV, NTP_SCALE_SHIFT); 191 txc->jitter = pps_jitter; 192 if (!(time_status & STA_NANO)) 193 txc->jitter /= NSEC_PER_USEC; 194 txc->shift = pps_shift; 195 txc->stabil = pps_stabil; 196 txc->jitcnt = pps_jitcnt; 197 txc->calcnt = pps_calcnt; 198 txc->errcnt = pps_errcnt; 199 txc->stbcnt = pps_stbcnt; 200} 201 202#else /* !CONFIG_NTP_PPS */ 203 204static inline s64 ntp_offset_chunk(s64 offset) 205{ 206 return shift_right(offset, SHIFT_PLL + time_constant); 207} 208 209static inline void pps_reset_freq_interval(void) {} 210static inline void pps_clear(void) {} 211static inline void pps_dec_valid(void) {} 212static inline void pps_set_freq(s64 freq) {} 213 214static inline int is_error_status(int status) 215{ 216 return status & (STA_UNSYNC|STA_CLOCKERR); 217} 218 219static inline void pps_fill_timex(struct timex *txc) 220{ 221 /* PPS is not implemented, so these are zero */ 222 txc->ppsfreq = 0; 223 txc->jitter = 0; 224 txc->shift = 0; 225 txc->stabil = 0; 226 txc->jitcnt = 0; 227 txc->calcnt = 0; 228 txc->errcnt = 0; 229 txc->stbcnt = 0; 230} 231 232#endif /* CONFIG_NTP_PPS */ 233 234/* |
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78 * NTP methods: 79 */ 80 81/* 82 * Update (tick_length, tick_length_base, tick_nsec), based 83 * on (tick_usec, ntp_tick_adj, time_freq): 84 */ 85static void ntp_update_frequency(void) --- 94 unchanged lines hidden (view full) --- 180 time_status |= STA_UNSYNC; 181 time_maxerror = NTP_PHASE_LIMIT; 182 time_esterror = NTP_PHASE_LIMIT; 183 184 ntp_update_frequency(); 185 186 tick_length = tick_length_base; 187 time_offset = 0; | 235 * NTP methods: 236 */ 237 238/* 239 * Update (tick_length, tick_length_base, tick_nsec), based 240 * on (tick_usec, ntp_tick_adj, time_freq): 241 */ 242static void ntp_update_frequency(void) --- 94 unchanged lines hidden (view full) --- 337 time_status |= STA_UNSYNC; 338 time_maxerror = NTP_PHASE_LIMIT; 339 time_esterror = NTP_PHASE_LIMIT; 340 341 ntp_update_frequency(); 342 343 tick_length = tick_length_base; 344 time_offset = 0; |
345 346 /* Clear PPS state variables */ 347 pps_clear(); |
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188} 189 190/* 191 * Leap second processing. If in leap-insert state at the end of the 192 * day, the system clock is set back one second; if in leap-delete 193 * state, the system clock is set ahead one second. 194 */ 195static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer) --- 49 unchanged lines hidden (view full) --- 245 246 /* Bump the maxerror field */ 247 time_maxerror += MAXFREQ / NSEC_PER_USEC; 248 if (time_maxerror > NTP_PHASE_LIMIT) { 249 time_maxerror = NTP_PHASE_LIMIT; 250 time_status |= STA_UNSYNC; 251 } 252 | 348} 349 350/* 351 * Leap second processing. If in leap-insert state at the end of the 352 * day, the system clock is set back one second; if in leap-delete 353 * state, the system clock is set ahead one second. 354 */ 355static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer) --- 49 unchanged lines hidden (view full) --- 405 406 /* Bump the maxerror field */ 407 time_maxerror += MAXFREQ / NSEC_PER_USEC; 408 if (time_maxerror > NTP_PHASE_LIMIT) { 409 time_maxerror = NTP_PHASE_LIMIT; 410 time_status |= STA_UNSYNC; 411 } 412 |
253 /* 254 * Compute the phase adjustment for the next second. The offset is 255 * reduced by a fixed factor times the time constant. 256 */ | 413 /* Compute the phase adjustment for the next second */ |
257 tick_length = tick_length_base; 258 | 414 tick_length = tick_length_base; 415 |
259 delta = shift_right(time_offset, SHIFT_PLL + time_constant); | 416 delta = ntp_offset_chunk(time_offset); |
260 time_offset -= delta; 261 tick_length += delta; 262 | 417 time_offset -= delta; 418 tick_length += delta; 419 |
420 /* Check PPS signal */ 421 pps_dec_valid(); 422 |
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263 if (!time_adjust) 264 return; 265 266 if (time_adjust > MAX_TICKADJ) { 267 time_adjust -= MAX_TICKADJ; 268 tick_length += MAX_TICKADJ_SCALED; 269 return; 270 } --- 93 unchanged lines hidden (view full) --- 364/* 365 * Propagate a new txc->status value into the NTP state: 366 */ 367static inline void process_adj_status(struct timex *txc, struct timespec *ts) 368{ 369 if ((time_status & STA_PLL) && !(txc->status & STA_PLL)) { 370 time_state = TIME_OK; 371 time_status = STA_UNSYNC; | 423 if (!time_adjust) 424 return; 425 426 if (time_adjust > MAX_TICKADJ) { 427 time_adjust -= MAX_TICKADJ; 428 tick_length += MAX_TICKADJ_SCALED; 429 return; 430 } --- 93 unchanged lines hidden (view full) --- 524/* 525 * Propagate a new txc->status value into the NTP state: 526 */ 527static inline void process_adj_status(struct timex *txc, struct timespec *ts) 528{ 529 if ((time_status & STA_PLL) && !(txc->status & STA_PLL)) { 530 time_state = TIME_OK; 531 time_status = STA_UNSYNC; |
532 /* restart PPS frequency calibration */ 533 pps_reset_freq_interval(); |
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372 } 373 374 /* 375 * If we turn on PLL adjustments then reset the 376 * reference time to current time. 377 */ 378 if (!(time_status & STA_PLL) && (txc->status & STA_PLL)) 379 time_reftime = get_seconds(); --- 33 unchanged lines hidden (view full) --- 413 414 if (txc->modes & ADJ_MICRO) 415 time_status &= ~STA_NANO; 416 417 if (txc->modes & ADJ_FREQUENCY) { 418 time_freq = txc->freq * PPM_SCALE; 419 time_freq = min(time_freq, MAXFREQ_SCALED); 420 time_freq = max(time_freq, -MAXFREQ_SCALED); | 534 } 535 536 /* 537 * If we turn on PLL adjustments then reset the 538 * reference time to current time. 539 */ 540 if (!(time_status & STA_PLL) && (txc->status & STA_PLL)) 541 time_reftime = get_seconds(); --- 33 unchanged lines hidden (view full) --- 575 576 if (txc->modes & ADJ_MICRO) 577 time_status &= ~STA_NANO; 578 579 if (txc->modes & ADJ_FREQUENCY) { 580 time_freq = txc->freq * PPM_SCALE; 581 time_freq = min(time_freq, MAXFREQ_SCALED); 582 time_freq = max(time_freq, -MAXFREQ_SCALED); |
583 /* update pps_freq */ 584 pps_set_freq(time_freq); |
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421 } 422 423 if (txc->modes & ADJ_MAXERROR) 424 time_maxerror = txc->maxerror; 425 426 if (txc->modes & ADJ_ESTERROR) 427 time_esterror = txc->esterror; 428 --- 74 unchanged lines hidden (view full) --- 503 504 txc->offset = shift_right(time_offset * NTP_INTERVAL_FREQ, 505 NTP_SCALE_SHIFT); 506 if (!(time_status & STA_NANO)) 507 txc->offset /= NSEC_PER_USEC; 508 } 509 510 result = time_state; /* mostly `TIME_OK' */ | 585 } 586 587 if (txc->modes & ADJ_MAXERROR) 588 time_maxerror = txc->maxerror; 589 590 if (txc->modes & ADJ_ESTERROR) 591 time_esterror = txc->esterror; 592 --- 74 unchanged lines hidden (view full) --- 667 668 txc->offset = shift_right(time_offset * NTP_INTERVAL_FREQ, 669 NTP_SCALE_SHIFT); 670 if (!(time_status & STA_NANO)) 671 txc->offset /= NSEC_PER_USEC; 672 } 673 674 result = time_state; /* mostly `TIME_OK' */ |
511 if (time_status & (STA_UNSYNC|STA_CLOCKERR)) | 675 /* check for errors */ 676 if (is_error_status(time_status)) |
512 result = TIME_ERROR; 513 514 txc->freq = shift_right((time_freq >> PPM_SCALE_INV_SHIFT) * 515 PPM_SCALE_INV, NTP_SCALE_SHIFT); 516 txc->maxerror = time_maxerror; 517 txc->esterror = time_esterror; 518 txc->status = time_status; 519 txc->constant = time_constant; 520 txc->precision = 1; 521 txc->tolerance = MAXFREQ_SCALED / PPM_SCALE; 522 txc->tick = tick_usec; 523 txc->tai = time_tai; 524 | 677 result = TIME_ERROR; 678 679 txc->freq = shift_right((time_freq >> PPM_SCALE_INV_SHIFT) * 680 PPM_SCALE_INV, NTP_SCALE_SHIFT); 681 txc->maxerror = time_maxerror; 682 txc->esterror = time_esterror; 683 txc->status = time_status; 684 txc->constant = time_constant; 685 txc->precision = 1; 686 txc->tolerance = MAXFREQ_SCALED / PPM_SCALE; 687 txc->tick = tick_usec; 688 txc->tai = time_tai; 689 |
525 /* PPS is not implemented, so these are zero */ 526 txc->ppsfreq = 0; 527 txc->jitter = 0; 528 txc->shift = 0; 529 txc->stabil = 0; 530 txc->jitcnt = 0; 531 txc->calcnt = 0; 532 txc->errcnt = 0; 533 txc->stbcnt = 0; | 690 /* fill PPS status fields */ 691 pps_fill_timex(txc); |
534 535 write_sequnlock_irq(&xtime_lock); 536 537 txc->time.tv_sec = ts.tv_sec; 538 txc->time.tv_usec = ts.tv_nsec; 539 if (!(time_status & STA_NANO)) 540 txc->time.tv_usec /= NSEC_PER_USEC; 541 542 notify_cmos_timer(); 543 544 return result; 545} 546 | 692 693 write_sequnlock_irq(&xtime_lock); 694 695 txc->time.tv_sec = ts.tv_sec; 696 txc->time.tv_usec = ts.tv_nsec; 697 if (!(time_status & STA_NANO)) 698 txc->time.tv_usec /= NSEC_PER_USEC; 699 700 notify_cmos_timer(); 701 702 return result; 703} 704 |
705#ifdef CONFIG_NTP_PPS 706 707/* actually struct pps_normtime is good old struct timespec, but it is 708 * semantically different (and it is the reason why it was invented): 709 * pps_normtime.nsec has a range of ( -NSEC_PER_SEC / 2, NSEC_PER_SEC / 2 ] 710 * while timespec.tv_nsec has a range of [0, NSEC_PER_SEC) */ 711struct pps_normtime { 712 __kernel_time_t sec; /* seconds */ 713 long nsec; /* nanoseconds */ 714}; 715 716/* normalize the timestamp so that nsec is in the 717 ( -NSEC_PER_SEC / 2, NSEC_PER_SEC / 2 ] interval */ 718static inline struct pps_normtime pps_normalize_ts(struct timespec ts) 719{ 720 struct pps_normtime norm = { 721 .sec = ts.tv_sec, 722 .nsec = ts.tv_nsec 723 }; 724 725 if (norm.nsec > (NSEC_PER_SEC >> 1)) { 726 norm.nsec -= NSEC_PER_SEC; 727 norm.sec++; 728 } 729 730 return norm; 731} 732 733/* get current phase correction and jitter */ 734static inline long pps_phase_filter_get(long *jitter) 735{ 736 *jitter = pps_tf[0] - pps_tf[1]; 737 if (*jitter < 0) 738 *jitter = -*jitter; 739 740 /* TODO: test various filters */ 741 return pps_tf[0]; 742} 743 744/* add the sample to the phase filter */ 745static inline void pps_phase_filter_add(long err) 746{ 747 pps_tf[2] = pps_tf[1]; 748 pps_tf[1] = pps_tf[0]; 749 pps_tf[0] = err; 750} 751 752/* decrease frequency calibration interval length. 753 * It is halved after four consecutive unstable intervals. 754 */ 755static inline void pps_dec_freq_interval(void) 756{ 757 if (--pps_intcnt <= -PPS_INTCOUNT) { 758 pps_intcnt = -PPS_INTCOUNT; 759 if (pps_shift > PPS_INTMIN) { 760 pps_shift--; 761 pps_intcnt = 0; 762 } 763 } 764} 765 766/* increase frequency calibration interval length. 767 * It is doubled after four consecutive stable intervals. 768 */ 769static inline void pps_inc_freq_interval(void) 770{ 771 if (++pps_intcnt >= PPS_INTCOUNT) { 772 pps_intcnt = PPS_INTCOUNT; 773 if (pps_shift < PPS_INTMAX) { 774 pps_shift++; 775 pps_intcnt = 0; 776 } 777 } 778} 779 780/* update clock frequency based on MONOTONIC_RAW clock PPS signal 781 * timestamps 782 * 783 * At the end of the calibration interval the difference between the 784 * first and last MONOTONIC_RAW clock timestamps divided by the length 785 * of the interval becomes the frequency update. If the interval was 786 * too long, the data are discarded. 787 * Returns the difference between old and new frequency values. 788 */ 789static long hardpps_update_freq(struct pps_normtime freq_norm) 790{ 791 long delta, delta_mod; 792 s64 ftemp; 793 794 /* check if the frequency interval was too long */ 795 if (freq_norm.sec > (2 << pps_shift)) { 796 time_status |= STA_PPSERROR; 797 pps_errcnt++; 798 pps_dec_freq_interval(); 799 pr_err("hardpps: PPSERROR: interval too long - %ld s\n", 800 freq_norm.sec); 801 return 0; 802 } 803 804 /* here the raw frequency offset and wander (stability) is 805 * calculated. If the wander is less than the wander threshold 806 * the interval is increased; otherwise it is decreased. 807 */ 808 ftemp = div_s64(((s64)(-freq_norm.nsec)) << NTP_SCALE_SHIFT, 809 freq_norm.sec); 810 delta = shift_right(ftemp - pps_freq, NTP_SCALE_SHIFT); 811 pps_freq = ftemp; 812 if (delta > PPS_MAXWANDER || delta < -PPS_MAXWANDER) { 813 pr_warning("hardpps: PPSWANDER: change=%ld\n", delta); 814 time_status |= STA_PPSWANDER; 815 pps_stbcnt++; 816 pps_dec_freq_interval(); 817 } else { /* good sample */ 818 pps_inc_freq_interval(); 819 } 820 821 /* the stability metric is calculated as the average of recent 822 * frequency changes, but is used only for performance 823 * monitoring 824 */ 825 delta_mod = delta; 826 if (delta_mod < 0) 827 delta_mod = -delta_mod; 828 pps_stabil += (div_s64(((s64)delta_mod) << 829 (NTP_SCALE_SHIFT - SHIFT_USEC), 830 NSEC_PER_USEC) - pps_stabil) >> PPS_INTMIN; 831 832 /* if enabled, the system clock frequency is updated */ 833 if ((time_status & STA_PPSFREQ) != 0 && 834 (time_status & STA_FREQHOLD) == 0) { 835 time_freq = pps_freq; 836 ntp_update_frequency(); 837 } 838 839 return delta; 840} 841 842/* correct REALTIME clock phase error against PPS signal */ 843static void hardpps_update_phase(long error) 844{ 845 long correction = -error; 846 long jitter; 847 848 /* add the sample to the median filter */ 849 pps_phase_filter_add(correction); 850 correction = pps_phase_filter_get(&jitter); 851 852 /* Nominal jitter is due to PPS signal noise. If it exceeds the 853 * threshold, the sample is discarded; otherwise, if so enabled, 854 * the time offset is updated. 855 */ 856 if (jitter > (pps_jitter << PPS_POPCORN)) { 857 pr_warning("hardpps: PPSJITTER: jitter=%ld, limit=%ld\n", 858 jitter, (pps_jitter << PPS_POPCORN)); 859 time_status |= STA_PPSJITTER; 860 pps_jitcnt++; 861 } else if (time_status & STA_PPSTIME) { 862 /* correct the time using the phase offset */ 863 time_offset = div_s64(((s64)correction) << NTP_SCALE_SHIFT, 864 NTP_INTERVAL_FREQ); 865 /* cancel running adjtime() */ 866 time_adjust = 0; 867 } 868 /* update jitter */ 869 pps_jitter += (jitter - pps_jitter) >> PPS_INTMIN; 870} 871 872/* 873 * hardpps() - discipline CPU clock oscillator to external PPS signal 874 * 875 * This routine is called at each PPS signal arrival in order to 876 * discipline the CPU clock oscillator to the PPS signal. It takes two 877 * parameters: REALTIME and MONOTONIC_RAW clock timestamps. The former 878 * is used to correct clock phase error and the latter is used to 879 * correct the frequency. 880 * 881 * This code is based on David Mills's reference nanokernel 882 * implementation. It was mostly rewritten but keeps the same idea. 883 */ 884void hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts) 885{ 886 struct pps_normtime pts_norm, freq_norm; 887 unsigned long flags; 888 889 pts_norm = pps_normalize_ts(*phase_ts); 890 891 write_seqlock_irqsave(&xtime_lock, flags); 892 893 /* clear the error bits, they will be set again if needed */ 894 time_status &= ~(STA_PPSJITTER | STA_PPSWANDER | STA_PPSERROR); 895 896 /* indicate signal presence */ 897 time_status |= STA_PPSSIGNAL; 898 pps_valid = PPS_VALID; 899 900 /* when called for the first time, 901 * just start the frequency interval */ 902 if (unlikely(pps_fbase.tv_sec == 0)) { 903 pps_fbase = *raw_ts; 904 write_sequnlock_irqrestore(&xtime_lock, flags); 905 return; 906 } 907 908 /* ok, now we have a base for frequency calculation */ 909 freq_norm = pps_normalize_ts(timespec_sub(*raw_ts, pps_fbase)); 910 911 /* check that the signal is in the range 912 * [1s - MAXFREQ us, 1s + MAXFREQ us], otherwise reject it */ 913 if ((freq_norm.sec == 0) || 914 (freq_norm.nsec > MAXFREQ * freq_norm.sec) || 915 (freq_norm.nsec < -MAXFREQ * freq_norm.sec)) { 916 time_status |= STA_PPSJITTER; 917 /* restart the frequency calibration interval */ 918 pps_fbase = *raw_ts; 919 write_sequnlock_irqrestore(&xtime_lock, flags); 920 pr_err("hardpps: PPSJITTER: bad pulse\n"); 921 return; 922 } 923 924 /* signal is ok */ 925 926 /* check if the current frequency interval is finished */ 927 if (freq_norm.sec >= (1 << pps_shift)) { 928 pps_calcnt++; 929 /* restart the frequency calibration interval */ 930 pps_fbase = *raw_ts; 931 hardpps_update_freq(freq_norm); 932 } 933 934 hardpps_update_phase(pts_norm.nsec); 935 936 write_sequnlock_irqrestore(&xtime_lock, flags); 937} 938EXPORT_SYMBOL(hardpps); 939 940#endif /* CONFIG_NTP_PPS */ 941 |
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547static int __init ntp_tick_adj_setup(char *str) 548{ 549 ntp_tick_adj = simple_strtol(str, NULL, 0); 550 ntp_tick_adj <<= NTP_SCALE_SHIFT; 551 552 return 1; 553} 554 555__setup("ntp_tick_adj=", ntp_tick_adj_setup); 556 557void __init ntp_init(void) 558{ 559 ntp_clear(); 560 hrtimer_init(&leap_timer, CLOCK_REALTIME, HRTIMER_MODE_ABS); 561 leap_timer.function = ntp_leap_second; 562} | 942static int __init ntp_tick_adj_setup(char *str) 943{ 944 ntp_tick_adj = simple_strtol(str, NULL, 0); 945 ntp_tick_adj <<= NTP_SCALE_SHIFT; 946 947 return 1; 948} 949 950__setup("ntp_tick_adj=", ntp_tick_adj_setup); 951 952void __init ntp_init(void) 953{ 954 ntp_clear(); 955 hrtimer_init(&leap_timer, CLOCK_REALTIME, HRTIMER_MODE_ABS); 956 leap_timer.function = ntp_leap_second; 957} |