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/*
* 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.
*/
/*
* Copyright 1996-1997, 2002 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#ifndef _SYS_TIMEX_H
#define _SYS_TIMEX_H
#pragma ident "%Z%%M% %I% %E% SMI"
#ifdef __cplusplus
extern "C" {
#endif
#include <sys/types.h>
#include <sys/time.h>
#include <sys/syscall.h>
#include <sys/inttypes.h>
/*
* 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.
*
* SCALE_KG and SCALE_KF establish the damping of the PLL and are chosen
* for a slightly underdamped convergence characteristic. SCALE_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
* SCALE_KG and SCALE_KF values given and a time constant range from
* zero to MAXTC, the PLL will converge in 15 minutes to 16 hours,
* respectively.
*/
#define SCALE_KG (1<<6) /* phase factor (multiplier) */
#define SCALE_KF (1<<16) /* PLL frequency factor (multiplier) */
#define SCALE_KH (1<<2) /* FLL frequency factor (multiplier) */
#define MAXTC (1<<6) /* maximum time constant */
/*
* 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.
*
* SCALE_PHASE defines the scaling (multiplier) of the time_phase variable,
* which serves as a an extension to the low-order bits of the system
* clock variable time.tv_usec.
*
* SCALE_UPDATE defines the scaling (multiplier) of the time_offset variable,
* which represents the current time offset with respect to standard
* time.
*
* SCALE_USEC defines the scaling (multiplier) of the time_freq and
* time_tolerance variables, which represent the current frequency
* offset and maximum frequency tolerance.
*
* FINEUSEC is 1 us in SCALE_UPDATE units of the time_phase variable.
*/
#define SCALE_PHASE (1<<22) /* phase scale */
#define SCALE_USEC (1<<16)
#define SCALE_UPDATE (SCALE_KG * MAXTC) /* */
#define FINEUSEC (1<<22) /* 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. 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.
*
* MINSEC and MAXSEC define the lower and upper bounds on the interval
* between protocol updates.
*/
#define MAXPHASE 512000 /* max phase error (us) */
#define MAXFREQ (512 * SCALE_USEC) /* max freq error (100 ppm) */
#define MAXTIME (200 << PPS_AVG) /* max PPS error (jitter) (200 us) */
#define MINSEC 16 /* min interval between updates (s) */
#define MAXSEC 1200 /* max interval between updates (s) */
/*
* 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) */
/*
* 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_CLKB 0x4000 /* set clock B */
#define MOD_CLKA 0x8000 /* set 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 /* 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 occured */
#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) */
int32_t maxerror; /* maximum error (us) (ro) */
int32_t esterror; /* estimated error (us) (ro) */
};
#if defined(_SYSCALL32)
/* Kernel's view of _ILP32 application's ntptimeval struct */
struct ntptimeval32 {
struct timeval32 time;
int32_t maxerror;
int32_t esterror;
};
#endif /* _SYSCALL32 */
/*
* NTP daemon interface - (ntp_adjtime()) used to discipline CPU clock
* oscillator
*/
struct timex {
uint32_t modes; /* clock mode bits (wo) */
int32_t offset; /* time offset (us) (rw) */
int32_t freq; /* frequency offset (scaled ppm) (rw) */
int32_t maxerror; /* maximum error (us) (rw) */
int32_t esterror; /* estimated error (us) (rw) */
int32_t status; /* clock status bits (rw) */
int32_t constant; /* pll time constant (rw) */
int32_t precision; /* clock precision (us) (ro) */
int32_t tolerance; /* clock freq tolerance (scaled ppm) (ro) */
int32_t ppsfreq; /* pps frequency (scaled ppm) (ro) */
int32_t jitter; /* pps jitter (us) (ro) */
int32_t shift; /* interval duration (s) (shift) (ro) */
int32_t stabil; /* pps stability (scaled ppm) (ro) */
int32_t jitcnt; /* jitter limit exceeded (ro) */
int32_t calcnt; /* calibration intervals (ro) */
int32_t errcnt; /* calibration errors (ro) */
int32_t stbcnt; /* stability limit exceeded (ro) */
};
#if defined(__STDC__)
/*
* NTP syscalls
*/
int ntp_gettime(struct ntptimeval *);
int ntp_adjtime(struct timex *);
#else
int ntp_gettime();
int ntp_adjtime();
#endif /* __STDC__ */
#ifdef _KERNEL
extern int32_t time_state; /* clock state */
extern int32_t time_status; /* clock status bits */
extern int32_t time_offset; /* time adjustment (us) */
extern int32_t time_freq; /* frequency offset (scaled ppm) */
extern int32_t time_maxerror; /* maximum error (us) */
extern int32_t time_esterror; /* estimated error (us) */
extern int32_t time_constant; /* pll time constant */
extern int32_t time_precision; /* clock precision (us) */
extern int32_t time_tolerance; /* frequency tolerance (scaled ppm) */
extern int32_t pps_shift; /* interval duration (s) (shift) */
extern int32_t pps_freq; /* pps frequency offset (scaled ppm) */
extern int32_t pps_jitter; /* pps jitter (us) */
extern int32_t pps_stabil; /* pps stability (scaled ppm) */
extern int32_t pps_jitcnt; /* jitter limit exceeded */
extern int32_t pps_calcnt; /* calibration intervals */
extern int32_t pps_errcnt; /* calibration errors */
extern int32_t pps_stbcnt; /* stability limit exceeded */
extern void clock_update(int);
extern void ddi_hardpps(struct timeval *, int);
#endif /* _KERNEL */
#ifdef __cplusplus
}
#endif
#endif /* _SYS_TIMEX_H */
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