timex.h

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/*****************************************************************************
 *                                                                           *
 * Copyright (c) David L. Mills 1993                                         *
 *                                                                           *
 * Permission to use, copy, modify, and distribute this software and its     *
 * documentation for any purpose and without fee is hereby granted, provided *
 * that the above copyright notice appears in all copies and that both the   *
 * copyright notice and this permission notice appear in supporting          *
 * documentation, and that the name University of Delaware not be used in    *
 * advertising or publicity pertaining to distribution of the software       *
 * without specific, written prior permission.  The University of Delaware   *
 * makes no representations about the suitability this software for any      *
 * purpose.  It is provided "as is" without express or implied warranty.     *
 *                                                                           *
 *****************************************************************************/

/*
 * Modification history timex.h
 *
 * 29 Dec 97    Russell King
 *  Moved CLOCK_TICK_RATE, CLOCK_TICK_FACTOR and FINETUNE to asm/timex.h
 *  for ARM machines
 *
 *  9 Jan 97    Adrian Sun
 *      Shifted LATCH define to allow access to alpha machines.
 *
 * 26 Sep 94    David L. Mills
 *  Added defines for hybrid phase/frequency-lock loop.
 *
 * 19 Mar 94    David L. Mills
 *  Moved defines from kernel routines to header file and added new
 *  defines for PPS phase-lock loop.
 *
 * 20 Feb 94    David L. Mills
 *  Revised status codes and structures for external clock and PPS
 *  signal discipline.
 *
 * 28 Nov 93    David L. Mills
 *  Adjusted parameters to improve stability and increase poll
 *  interval.
 *
 * 17 Sep 93    David L. Mills
 *      Created file $NTP/include/sys/timex.h
 * 07 Oct 93    Torsten Duwe
 *      Derived linux/timex.h
 * 1995-08-13    Torsten Duwe
 *      kernel PLL updated to 1994-12-13 specs (rfc-1589)
 * 1997-08-30    Ulrich Windl
 *      Added new constant NTP_PHASE_LIMIT
 * 2004-08-12    Christoph Lameter
 *      Reworked time interpolation logic
 */
#ifndef _UAPI_LINUX_TIMEX_H
#define _UAPI_LINUX_TIMEX_H

#include <linux/time.h>

#define NTP_API     4   /* NTP API version */

/*
 * syscall interface - used (mainly by NTP daemon)
 * to discipline kernel clock oscillator
 */
struct timex {
    unsigned int modes; /* mode selector */
    long offset;        /* time offset (usec) */
    long freq;      /* frequency offset (scaled ppm) */
    long maxerror;      /* maximum error (usec) */
    long esterror;      /* estimated error (usec) */
    int status;     /* clock command/status */
    long constant;      /* pll time constant */
    long precision;     /* clock precision (usec) (read only) */
    long tolerance;     /* clock frequency tolerance (ppm)
                 * (read only)
                 */
    struct timeval time;    /* (read only, except for ADJ_SETOFFSET) */
    long tick;      /* (modified) usecs between clock ticks */

    long ppsfreq;           /* pps frequency (scaled ppm) (ro) */
    long jitter;            /* pps jitter (us) (ro) */
    int shift;              /* interval duration (s) (shift) (ro) */
    long stabil;            /* pps stability (scaled ppm) (ro) */
    long jitcnt;            /* jitter limit exceeded (ro) */
    long calcnt;            /* calibration intervals (ro) */
    long errcnt;            /* calibration errors (ro) */
    long stbcnt;            /* stability limit exceeded (ro) */

    int tai;        /* TAI offset (ro) */

    int  :32; int  :32; int  :32; int  :32;
    int  :32; int  :32; int  :32; int  :32;
    int  :32; int  :32; int  :32;
};

/*
 * Mode codes (timex.mode)
 */
#define ADJ_OFFSET      0x0001  /* time offset */
#define ADJ_FREQUENCY       0x0002  /* frequency offset */
#define ADJ_MAXERROR        0x0004  /* maximum time error */
#define ADJ_ESTERROR        0x0008  /* estimated time error */
#define ADJ_STATUS      0x0010  /* clock status */
#define ADJ_TIMECONST       0x0020  /* pll time constant */
#define ADJ_TAI         0x0080  /* set TAI offset */
#define ADJ_SETOFFSET       0x0100  /* add 'time' to current time */
#define ADJ_MICRO       0x1000  /* select microsecond resolution */
#define ADJ_NANO        0x2000  /* select nanosecond resolution */
#define ADJ_TICK        0x4000  /* tick value */

#ifndef __KERNEL__
#define ADJ_OFFSET_SINGLESHOT   0x8001  /* old-fashioned adjtime */
#define ADJ_OFFSET_SS_READ  0xa001  /* read-only adjtime */
#endif

/* NTP userland likes the MOD_ prefix better */
#define MOD_OFFSET  ADJ_OFFSET
#define MOD_FREQUENCY   ADJ_FREQUENCY
#define MOD_MAXERROR    ADJ_MAXERROR
#define MOD_ESTERROR    ADJ_ESTERROR
#define MOD_STATUS  ADJ_STATUS
#define MOD_TIMECONST   ADJ_TIMECONST
#define MOD_TAI ADJ_TAI
#define MOD_MICRO   ADJ_MICRO
#define MOD_NANO    ADJ_NANO


/*
 * Status codes (timex.status)
 */
#define STA_PLL     0x0001  /* enable PLL updates (rw) */
#define STA_PPSFREQ 0x0002  /* enable PPS freq discipline (rw) */
#define STA_PPSTIME 0x0004  /* enable PPS time discipline (rw) */
#define STA_FLL     0x0008  /* select frequency-lock mode (rw) */

#define STA_INS     0x0010  /* insert leap (rw) */
#define STA_DEL     0x0020  /* delete leap (rw) */
#define STA_UNSYNC  0x0040  /* clock unsynchronized (rw) */
#define STA_FREQHOLD    0x0080  /* hold frequency (rw) */

#define STA_PPSSIGNAL   0x0100  /* PPS signal present (ro) */
#define STA_PPSJITTER   0x0200  /* PPS signal jitter exceeded (ro) */
#define STA_PPSWANDER   0x0400  /* PPS signal wander exceeded (ro) */
#define STA_PPSERROR    0x0800  /* PPS signal calibration error (ro) */

#define STA_CLOCKERR    0x1000  /* clock hardware fault (ro) */
#define STA_NANO    0x2000  /* resolution (0 = us, 1 = ns) (ro) */
#define STA_MODE    0x4000  /* mode (0 = PLL, 1 = FLL) (ro) */
#define STA_CLK     0x8000  /* clock source (0 = A, 1 = B) (ro) */

/* read-only bits */
#define STA_RONLY (STA_PPSSIGNAL | STA_PPSJITTER | STA_PPSWANDER | \
    STA_PPSERROR | STA_CLOCKERR | STA_NANO | STA_MODE | STA_CLK)

/*
 * Clock states (time_state)
 */
#define TIME_OK     0   /* clock synchronized, no leap second */
#define TIME_INS    1   /* insert leap second */
#define TIME_DEL    2   /* delete leap second */
#define TIME_OOP    3   /* leap second in progress */
#define TIME_WAIT   4   /* leap second has occurred */
#define TIME_ERROR  5   /* clock not synchronized */
#define TIME_BAD    TIME_ERROR /* bw compat */


#endif /* _UAPI_LINUX_TIMEX_H */