312 lines
12 KiB
C
312 lines
12 KiB
C
/* $NetBSD: timex.h,v 1.1.1.1 2000/03/29 12:38:49 simonb Exp $ */
|
|
|
|
/******************************************************************************
|
|
* *
|
|
* Copyright (c) David L. Mills 1993, 1994 *
|
|
* *
|
|
* 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
|
|
*
|
|
* 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
|
|
* private syscalls and data structures and require specific kernel
|
|
* support.
|
|
*
|
|
* NAME
|
|
* ntp_gettime - NTP user application interface
|
|
*
|
|
* SYNOPSIS
|
|
* #include <sys/timex.h>
|
|
*
|
|
* int syscall(SYS_ntp_gettime, tptr)
|
|
*
|
|
* int SYS_ntp_gettime defined in syscall.h header file
|
|
* struct ntptimeval *tptr pointer to ntptimeval structure
|
|
*
|
|
* NAME
|
|
* ntp_adjtime - NTP daemon application interface
|
|
*
|
|
* SYNOPSIS
|
|
* #include <sys/timex.h>
|
|
*
|
|
* int syscall(SYS_ntp_adjtime, mode, tptr)
|
|
*
|
|
* int SYS_ntp_adjtime defined in syscall.h header file
|
|
* struct timex *tptr pointer to timex structure
|
|
*
|
|
*/
|
|
#ifndef _SYS_TIMEX_H_
|
|
#define _SYS_TIMEX_H_ 1
|
|
|
|
#ifndef MSDOS /* Microsoft specific */
|
|
#include <sys/syscall.h>
|
|
#endif /* MSDOS */
|
|
|
|
/*
|
|
* The following defines establish the engineering parameters of the
|
|
* phase-lock loop (PLL) model used in the kernel implementation. These
|
|
* parameters have been carefully chosen by analysis for good stability
|
|
* and wide dynamic range.
|
|
*
|
|
* The hz variable is defined in the kernel build environment. It
|
|
* establishes the timer interrupt frequency, 100 Hz for the SunOS
|
|
* kernel, 256 Hz for the Ultrix kernel and 1024 Hz for the OSF/1
|
|
* kernel. SHIFT_HZ expresses the same value as the nearest power of two
|
|
* in order to avoid hardware multiply operations.
|
|
*
|
|
* SHIFT_KG and SHIFT_KF establish the damping of the PLL and are chosen
|
|
* for a slightly underdamped convergence characteristic. SHIFT_KH
|
|
* establishes the damping of the FLL and is chosen by wisdom and black
|
|
* art.
|
|
*
|
|
* MAXTC establishes the maximum time constant of the PLL. With the
|
|
* SHIFT_KG and SHIFT_KF values given and a time constant range from
|
|
* zero to MAXTC, the PLL will converge in 15 minutes to 16 hours,
|
|
* respectively.
|
|
*/
|
|
#define SHIFT_HZ 7 /* log2(hz) */
|
|
#define SHIFT_KG 6 /* phase factor (shift) */
|
|
#define SHIFT_KF 16 /* PLL frequency factor (shift) */
|
|
#define SHIFT_KH 2 /* FLL frequency factor (shift) */
|
|
#define MAXTC 6 /* maximum time constant (shift) */
|
|
|
|
/*
|
|
* The following defines establish the scaling of the various variables
|
|
* used by the PLL. They are chosen to allow the greatest precision
|
|
* possible without overflow of a 32-bit word.
|
|
*
|
|
* SHIFT_SCALE defines the scaling (shift) of the time_phase variable,
|
|
* which serves as a an extension to the low-order bits of the system
|
|
* clock variable time.tv_usec.
|
|
*
|
|
* SHIFT_UPDATE defines the scaling (shift) of the time_offset variable,
|
|
* which represents the current time offset with respect to standard
|
|
* time.
|
|
*
|
|
* SHIFT_USEC defines the scaling (shift) of the time_freq and
|
|
* time_tolerance variables, which represent the current frequency
|
|
* offset and maximum frequency tolerance.
|
|
*
|
|
* FINEUSEC is 1 us in SHIFT_UPDATE units of the time_phase variable.
|
|
*/
|
|
#define SHIFT_SCALE 22 /* phase scale (shift) */
|
|
#define SHIFT_UPDATE (SHIFT_KG + MAXTC) /* time offset scale (shift) */
|
|
#define SHIFT_USEC 16 /* frequency offset scale (shift) */
|
|
#define FINEUSEC (1L << SHIFT_SCALE) /* 1 us in phase units */
|
|
|
|
/*
|
|
* The following defines establish the performance envelope of the PLL.
|
|
* They insure it operates within predefined limits, in order to satisfy
|
|
* correctness assertions. An excursion which exceeds these bounds is
|
|
* clamped to the bound and operation proceeds accordingly. In practice,
|
|
* this can occur only if something has failed or is operating out of
|
|
* tolerance, but otherwise the PLL continues to operate in a stable
|
|
* mode.
|
|
*
|
|
* MAXPHASE must be set greater than or equal to CLOCK.MAX (128 ms), as
|
|
* defined in the NTP specification. CLOCK.MAX establishes the maximum
|
|
* time offset allowed before the system time is reset, rather than
|
|
* incrementally adjusted. Here, the maximum offset is clamped to
|
|
* MAXPHASE only in order to prevent overflow errors due to defective
|
|
* protocol implementations.
|
|
*
|
|
* MAXFREQ is the maximum frequency tolerance of the CPU clock
|
|
* oscillator plus the maximum slew rate allowed by the protocol. It
|
|
* should be set to at least the frequency tolerance of the oscillator
|
|
* plus 100 ppm for vernier frequency adjustments. If the kernel
|
|
* PPS discipline code is configured (PPS_SYNC), the oscillator time and
|
|
* frequency are disciplined to an external source, presumably with
|
|
* negligible time and frequency error relative to UTC, and MAXFREQ can
|
|
* be reduced.
|
|
*
|
|
* MAXTIME is the maximum jitter tolerance of the PPS signal if the
|
|
* kernel PPS discipline code is configured (PPS_SYNC).
|
|
*
|
|
* MINSEC and MAXSEC define the lower and upper bounds on the interval
|
|
* between protocol updates.
|
|
*/
|
|
#define MAXPHASE 512000L /* max phase error (us) */
|
|
#ifdef PPS_SYNC
|
|
#define MAXFREQ (512L << SHIFT_USEC) /* max freq error (100 ppm) */
|
|
#define MAXTIME (200L << PPS_AVG) /* max PPS error (jitter) (200 us) */
|
|
#else
|
|
#define MAXFREQ (512L << SHIFT_USEC) /* max freq error (200 ppm) */
|
|
#endif /* PPS_SYNC */
|
|
#define MINSEC 16L /* min interval between updates (s) */
|
|
#define MAXSEC 1200L /* max interval between updates (s) */
|
|
|
|
#ifdef PPS_SYNC
|
|
/*
|
|
* The following defines are used only if a pulse-per-second (PPS)
|
|
* signal is available and connected via a modem control lead, such as
|
|
* produced by the optional ppsclock feature incorporated in the Sun
|
|
* asynch driver. They establish the design parameters of the frequency-
|
|
* lock loop used to discipline the CPU clock oscillator to the PPS
|
|
* signal.
|
|
*
|
|
* PPS_AVG is the averaging factor for the frequency loop, as well as
|
|
* the time and frequency dispersion.
|
|
*
|
|
* PPS_SHIFT and PPS_SHIFTMAX specify the minimum and maximum
|
|
* calibration intervals, respectively, in seconds as a power of two.
|
|
*
|
|
* PPS_VALID is the maximum interval before the PPS signal is considered
|
|
* invalid and protocol updates used directly instead.
|
|
*
|
|
* MAXGLITCH is the maximum interval before a time offset of more than
|
|
* MAXTIME is believed.
|
|
*/
|
|
#define PPS_AVG 2 /* pps averaging constant (shift) */
|
|
#define PPS_SHIFT 2 /* min interval duration (s) (shift) */
|
|
#define PPS_SHIFTMAX 8 /* max interval duration (s) (shift) */
|
|
#define PPS_VALID 120 /* pps signal watchdog max (s) */
|
|
#define MAXGLITCH 30 /* pps signal glitch max (s) */
|
|
#endif /* PPS_SYNC */
|
|
|
|
/*
|
|
* The following defines and structures define the user interface for
|
|
* the ntp_gettime() and ntp_adjtime() system calls.
|
|
*
|
|
* 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_CANSCALE 0x0040 /* kernel can scale offset field */
|
|
#define MOD_DOSCALE 0x0080 /* userland wants to scale offset field */
|
|
|
|
/*
|
|
* 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_RONLY (STA_PPSSIGNAL | STA_PPSJITTER | STA_PPSWANDER | \
|
|
STA_PPSERROR | STA_CLOCKERR) /* read-only bits */
|
|
|
|
/*
|
|
* 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 occurred */
|
|
#define TIME_ERROR 5 /* clock not synchronized */
|
|
|
|
/*
|
|
* NTP user interface (ntp_gettime()) - used to read kernel clock values
|
|
*
|
|
* Note: maximum error = NTP synch distance = dispersion + delay / 2;
|
|
* estimated error = NTP dispersion.
|
|
*/
|
|
struct ntptimeval {
|
|
struct timeval time; /* current time (ro) */
|
|
long maxerror; /* maximum error (us) (ro) */
|
|
long esterror; /* estimated error (us) (ro) */
|
|
};
|
|
|
|
/*
|
|
* NTP daemon interface - (ntp_adjtime()) used to discipline CPU clock
|
|
* oscillator
|
|
*/
|
|
struct timex {
|
|
unsigned int modes; /* clock mode bits (wo) */
|
|
long offset; /* time offset (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; /* pll time constant (rw) */
|
|
long precision; /* clock precision (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.
|
|
*/
|
|
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) */
|
|
|
|
};
|
|
#ifdef __FreeBSD__
|
|
|
|
/*
|
|
* sysctl identifiers underneath kern.ntp_pll
|
|
*/
|
|
#define NTP_PLL_GETTIME 1 /* used by ntp_gettime() */
|
|
#define NTP_PLL_MAXID 2 /* number of valid ids */
|
|
|
|
#define NTP_PLL_NAMES { \
|
|
{ 0, 0 }, \
|
|
{ "gettime", CTLTYPE_STRUCT }, \
|
|
}
|
|
|
|
#ifndef KERNEL
|
|
#include <sys/cdefs.h>
|
|
|
|
__BEGIN_DECLS
|
|
extern int ntp_gettime __P((struct ntptimeval *));
|
|
extern int ntp_adjtime __P((struct timex *));
|
|
__END_DECLS
|
|
|
|
#endif /* not KERNEL */
|
|
|
|
#endif /* __FreeBSD__ */
|
|
#endif /* _SYS_TIMEX_H_ */
|