From 2b9936f3f7ab47a89436d4fa3b70e4c09dd2398e Mon Sep 17 00:00:00 2001 From: Thorsten Lockert Date: Mon, 29 Jan 1996 23:05:12 +0000 Subject: Add kernel PLL for system clock Add ntp_adjtime() and ntp_gettime() system calls Mostly stolen from FreeBSD --- sys/kern/kern_ntptime.c | 268 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 268 insertions(+) create mode 100644 sys/kern/kern_ntptime.c (limited to 'sys/kern/kern_ntptime.c') diff --git a/sys/kern/kern_ntptime.c b/sys/kern/kern_ntptime.c new file mode 100644 index 00000000000..3a575000db4 --- /dev/null +++ b/sys/kern/kern_ntptime.c @@ -0,0 +1,268 @@ +/****************************************************************************** + * * + * 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 kern_ntptime.c + * + * 24 Sep 94 David L. Mills + * Tightened code at exits. + * + * 24 Mar 94 David L. Mills + * Revised syscall interface to include new variables for PPS + * time discipline. + * + * 14 Feb 94 David L. Mills + * Added code for external clock + * + * 28 Nov 93 David L. Mills + * Revised frequency scaling to conform with adjusted parameters + * + * 17 Sep 93 David L. Mills + * Created file + */ +/* + * ntp_gettime(), ntp_adjtime() - precision time interface for SunOS + * V4.1.1 and V4.1.3 + * + * These routines consitute the Network Time Protocol (NTP) interfaces + * for user and daemon application programs. The ntp_gettime() routine + * provides the time, maximum error (synch distance) and estimated error + * (dispersion) to client user application programs. The ntp_adjtime() + * routine is used by the NTP daemon to adjust the system clock to an + * externally derived time. The time offset and related variables set by + * this routine are used by hardclock() to adjust the phase and + * frequency of the phase-lock loop which controls the system clock. + */ +#include +#include +#include +#include +#include + +#include +#include + +/* + * The following variables are used by the hardclock() routine in the + * kern_clock.c module and are described in that module. + */ +extern int time_state; /* clock state */ +extern int time_status; /* clock status bits */ +extern long time_offset; /* time adjustment (us) */ +extern long time_freq; /* frequency offset (scaled ppm) */ +extern long time_maxerror; /* maximum error (us) */ +extern long time_esterror; /* estimated error (us) */ +extern long time_constant; /* pll time constant */ +extern long time_precision; /* clock precision (us) */ +extern long time_tolerance; /* frequency tolerance (scaled ppm) */ + +#ifdef PPS_SYNC +/* + * The following variables are used only if the PPS signal discipline + * is configured in the kernel. + */ +extern int pps_shift; /* interval duration (s) (shift) */ +extern long pps_freq; /* pps frequency offset (scaled ppm) */ +extern long pps_jitter; /* pps jitter (us) */ +extern long pps_stabil; /* pps stability (scaled ppm) */ +extern long pps_jitcnt; /* jitter limit exceeded */ +extern long pps_calcnt; /* calibration intervals */ +extern long pps_errcnt; /* calibration errors */ +extern long pps_stbcnt; /* stability limit exceeded */ +#endif /* PPS_SYNC */ + +/* + * ntp_gettime() - NTP user application interface + */ +int +sys_ntp_gettime(p, v, retval) + struct proc *p; + void *v; + register_t *retval; +{ + register struct sys_ntp_gettime_args /* { + syscallarg(struct ntptimeval *) tp; + } */ *uap = v; + struct timeval atv; + struct ntptimeval ntv; + int error, s; + + if (SCARG(uap, tp)) { + s = splclock(); +#ifdef EXT_CLOCK + /* + * The microtime() external clock routine returns a + * status code. If less than zero, we declare an error + * in the clock status word and return the kernel + * (software) time variable. While there are other + * places that call microtime(), this is the only place + * that matters from an application point of view. + */ + if (microtime(&atv) < 0) { + time_status |= STA_CLOCKERR; + ntv.time = time; + } else + time_status &= ~STA_CLOCKERR; +#else /* EXT_CLOCK */ + microtime(&atv); +#endif /* EXT_CLOCK */ + ntv.time = atv; + ntv.maxerror = time_maxerror; + ntv.esterror = time_esterror; + (void) splx(s); + + error = copyout((caddr_t)&ntv, (caddr_t)SCARG(uap, tp), + sizeof (ntv)); + } + if (!error) { + + /* + * Status word error decode. If any of these conditions + * occur, an error is returned, instead of the status + * word. Most applications will care only about the fact + * the system clock may not be trusted, not about the + * details. + * + * Hardware or software error + */ + if ((time_status & (STA_UNSYNC | STA_CLOCKERR)) || + + /* + * PPS signal lost when either time or frequency + * synchronization requested + */ + (time_status & (STA_PPSFREQ | STA_PPSTIME) && + !(time_status & STA_PPSSIGNAL)) || + + /* + * PPS jitter exceeded when time synchronization + * requested + */ + (time_status & STA_PPSTIME && + time_status & STA_PPSJITTER) || + + /* + * PPS wander exceeded or calibration error when + * frequency synchronization requested + */ + (time_status & STA_PPSFREQ && + time_status & (STA_PPSWANDER | STA_PPSERROR))) + *retval = TIME_ERROR; + else + *retval = time_state; + } + return (error); +} + +/* + * ntp_adjtime() - NTP daemon application interface + */ +int +sys_ntp_adjtime(p, v, retval) + struct proc *p; + void *v; + register_t *retval; +{ + register struct sys_ntp_adjtime_args /* { + syscallarg(struct timex *) tp; + } */ *uap = v; + struct timex ntv; + int modes; + int error, s; + + error = copyin((caddr_t)SCARG(uap, tp), (caddr_t)&ntv, sizeof(ntv)); + if (error) + return (error); + + /* + * Update selected clock variables - only the superuser can + * change anything. Note that there is no error checking here on + * the assumption the superuser should know what it is doing. + */ + modes = ntv.modes; + if (!suser(p->p_ucred, &p->p_acflag) && modes != 0) + return; + s = splclock(); + if (modes & MOD_FREQUENCY) +#ifdef PPS_SYNC + time_freq = ntv.freq - pps_freq; +#else /* PPS_SYNC */ + time_freq = ntv.freq; +#endif /* PPS_SYNC */ + if (modes & MOD_MAXERROR) + time_maxerror = ntv.maxerror; + if (modes & MOD_ESTERROR) + time_esterror = ntv.esterror; + if (modes & MOD_STATUS) { + time_status &= STA_RONLY; + time_status |= ntv.status & ~STA_RONLY; + } + if (modes & MOD_TIMECONST) + time_constant = ntv.constant; + if (modes & MOD_OFFSET) + hardupdate(ntv.offset); + + /* + * Retrieve all clock variables + */ + if (time_offset < 0) + ntv.offset = -(-time_offset >> SHIFT_UPDATE); + else + ntv.offset = time_offset >> SHIFT_UPDATE; +#ifdef PPS_SYNC + ntv.freq = time_freq + pps_freq; +#else /* PPS_SYNC */ + ntv.freq = time_freq; +#endif /* PPS_SYNC */ + ntv.maxerror = time_maxerror; + ntv.esterror = time_esterror; + ntv.status = time_status; + ntv.constant = time_constant; + ntv.precision = time_precision; + ntv.tolerance = time_tolerance; +#ifdef PPS_SYNC + ntv.shift = pps_shift; + ntv.ppsfreq = pps_freq; + ntv.jitter = pps_jitter >> PPS_AVG; + ntv.stabil = pps_stabil; + ntv.calcnt = pps_calcnt; + ntv.errcnt = pps_errcnt; + ntv.jitcnt = pps_jitcnt; + ntv.stbcnt = pps_stbcnt; +#endif /* PPS_SYNC */ + (void)splx(s); + + error = copyout((caddr_t)&ntv, (caddr_t)SCARG(uap, tp), + sizeof(ntv)); + if (!error) { + + /* + * Status word error decode. See comments in + * ntp_gettime() routine. + */ + if ((time_status & (STA_UNSYNC | STA_CLOCKERR)) || + (time_status & (STA_PPSFREQ | STA_PPSTIME) && + !(time_status & STA_PPSSIGNAL)) || + (time_status & STA_PPSTIME && + time_status & STA_PPSJITTER) || + (time_status & STA_PPSFREQ && + time_status & (STA_PPSWANDER | STA_PPSERROR))) + *retval = TIME_ERROR; + else + *retval = time_state; + } + return (error); +} -- cgit v1.2.3