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/***********************************************************************
* *
* Copyright (c) David L. Mills 1993-1998 *
* *
* 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
*
* 17 Nov 98 David L. Mills
* Revised for nanosecond kernel and user interface.
*
* 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
*/
/*
* This header file defines the Network Time Protocol (NTP) interfaces
* for user and daemon application programs. These are implemented using
* defined syscalls and data structures and require specific kernel
* support.
*
* The original precision time kernels developed from 1993 have an
* ultimate resolution of one microsecond; however, the most recent
* kernels have an ultimate resolution of one nanosecond. In these
* kernels, a ntp_adjtime() syscalls can be used to determine which
* resolution is in use and to select either one at any time. The
* resolution selected affects the scaling of certain fields in the
* ntp_gettime() and ntp_adjtime() syscalls, as described below.
*
* NAME
* ntp_gettime - NTP user application interface
*
* SYNOPSIS
* #include <sys/timex.h>
*
* int ntp_gettime(struct ntptimeval *ntv);
*
* DESCRIPTION
* The time returned by ntp_gettime() is in a timespec structure,
* but may be in either microsecond (seconds and microseconds) or
* nanosecond (seconds and nanoseconds) format. The particular
* format in use is determined by the STA_NANO bit of the status
* word returned by the ntp_adjtime() syscall.
*
* NAME
* ntp_adjtime - NTP daemon application interface
*
* SYNOPSIS
* #include <sys/timex.h>
* #include <sys/syscall.h>
*
* int syscall(SYS_ntp_adjtime, tptr);
* int SYS_ntp_adjtime;
* struct timex *tptr;
*
* DESCRIPTION
* Certain fields of the timex structure are interpreted in either
* microseconds or nanoseconds according to the state of the
* STA_NANO bit in the status word. See the description below for
* further information.
*/
#ifndef _SYS_TIMEX_H_
#define _SYS_TIMEX_H_ 1
#define NTP_API 3 /* NTP API version */
#ifndef MSDOS /* Microsoft specific */
#include <sys/syscall.h>
#endif /* MSDOS */
/*
* The following defines establish the performance envelope of the
* kernel discipline loop. Phase or frequency errors greater than
* NAXPHASE or MAXFREQ are clamped to these maxima. For update intervals
* less than MINSEC, the loop always operates in PLL mode; while, for
* update intervals greater than MAXSEC, the loop always operates in FLL
* mode. Between these two limits the operating mode is selected by the
* STA_FLL bit in the status word.
*/
#define MAXPHASE 500000000L /* max phase error (ns) */
#define MAXFREQ 500000L /* max freq error (ns/s) */
#define MINSEC 256 /* min FLL update interval (s) */
#define MAXSEC 2048 /* max PLL update interval (s) */
#define NANOSECOND 1000000000L /* nanoseconds in one second */
#define SCALE_PPM (65536 / 1000) /* crude ns/s to scaled PPM */
#define MAXTC 10 /* max time constant in PLL mode */
/*
* The following defines and structures define the user interface for
* the ntp_gettime() and ntp_adjtime() syscalls.
*
* Control mode codes (timex.modes)
*/
#define MOD_OFFSET 0x0001 /* set time offset */
#define MOD_FREQUENCY 0x0002 /* set frequency offset */
#define MOD_MAXERROR 0x0004 /* set maximum time error */
#define MOD_ESTERROR 0x0008 /* set estimated time error */
#define MOD_STATUS 0x0010 /* set clock status bits */
#define MOD_TIMECONST 0x0020 /* set PLL time constant */
#define MOD_PLL 0x0400 /* select default PLL mode */
#define MOD_FLL 0x0800 /* select default FLL mode */
#define MOD_MICRO 0x1000 /* select microsecond resolution */
#define MOD_NANO 0x2000 /* select nanosecond resolution */
#define MOD_CLKB 0x4000 /* select clock B */
#define MOD_CLKA 0x8000 /* select clock A */
/*
* 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 /* enable FLL 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) */
#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 /* no leap second warning */
#define TIME_INS 1 /* insert leap second warning */
#define TIME_DEL 2 /* delete leap second warning */
#define TIME_OOP 3 /* leap second in progress */
#define TIME_WAIT 4 /* leap second has occured */
#define TIME_ERROR 5 /* error (see status word) */
/*
* NTP user interface (ntp_gettime()) - used to read kernel clock values
*
* Note: The time member is in microseconds if STA_NANO is zero and
* nanoseconds if not.
*/
struct ntptimeval {
struct timespec time; /* current time (ns) (ro) */
long maxerror; /* maximum error (us) (ro) */
long esterror; /* estimated error (us) (ro) */
int time_state; /* time status */
};
/*
* NTP daemon interface (ntp_adjtime()) - used to discipline CPU clock
* oscillator and determine status.
*
* Note: The offset, precision and jitter members are in microseconds if
* STA_NANO is zero and nanoseconds if not.
*/
struct timex {
unsigned int modes; /* clock mode bits (wo) */
long offset; /* time offset (ns/us) (rw) */
long freq; /* frequency offset (scaled PPM) (rw) */
long maxerror; /* maximum error (us) (rw) */
long esterror; /* estimated error (us) (rw) */
int status; /* clock status bits (rw) */
long constant; /* poll interval (log2 s) (rw) */
long precision; /* clock precision (ns/us) (ro) */
long tolerance; /* clock frequency tolerance (scaled
* PPM) (ro) */
/*
* The following read-only structure members are implemented
* only if the PPS signal discipline is configured in the
* kernel. They are included in all configurations to insure
* portability.
*/
long ppsfreq; /* PPS frequency (scaled PPM) (ro) */
long jitter; /* PPS jitter (ns/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) */
};
#ifdef __FreeBSD__
#ifdef KERNEL
struct timecounter;
void ntp_update_second __P((struct timecounter *tc));
#else /* !KERNEL */
#include <sys/cdefs.h>
__BEGIN_DECLS
int ntp_adjtime __P((struct timex *));
int ntp_gettime __P((struct ntptimeval *));
__END_DECLS
#endif /* KERNEL */
#endif /* __FreeBSD__ */
#endif /* !_SYS_TIMEX_H_ */