35
36#include "opt_ntp.h"
37
38#include <sys/param.h>
39#include <sys/systm.h>
40#include <sys/sysproto.h>
41#include <sys/eventhandler.h>
42#include <sys/kernel.h>
43#include <sys/priv.h>
44#include <sys/proc.h>
45#include <sys/lock.h>
46#include <sys/mutex.h>
47#include <sys/time.h>
48#include <sys/timex.h>
49#include <sys/timetc.h>
50#include <sys/timepps.h>
51#include <sys/syscallsubr.h>
52#include <sys/sysctl.h>
53
54#ifdef PPS_SYNC
55FEATURE(pps_sync, "Support usage of external PPS signal by kernel PLL");
56#endif
57
58/*
59 * Single-precision macros for 64-bit machines
60 */
61typedef int64_t l_fp;
62#define L_ADD(v, u) ((v) += (u))
63#define L_SUB(v, u) ((v) -= (u))
64#define L_ADDHI(v, a) ((v) += (int64_t)(a) << 32)
65#define L_NEG(v) ((v) = -(v))
66#define L_RSHIFT(v, n) \
67 do { \
68 if ((v) < 0) \
69 (v) = -(-(v) >> (n)); \
70 else \
71 (v) = (v) >> (n); \
72 } while (0)
73#define L_MPY(v, a) ((v) *= (a))
74#define L_CLR(v) ((v) = 0)
75#define L_ISNEG(v) ((v) < 0)
76#define L_LINT(v, a) ((v) = (int64_t)(a) << 32)
77#define L_GINT(v) ((v) < 0 ? -(-(v) >> 32) : (v) >> 32)
78
79/*
80 * Generic NTP kernel interface
81 *
82 * These routines constitute the Network Time Protocol (NTP) interfaces
83 * for user and daemon application programs. The ntp_gettime() routine
84 * provides the time, maximum error (synch distance) and estimated error
85 * (dispersion) to client user application programs. The ntp_adjtime()
86 * routine is used by the NTP daemon to adjust the system clock to an
87 * externally derived time. The time offset and related variables set by
88 * this routine are used by other routines in this module to adjust the
89 * phase and frequency of the clock discipline loop which controls the
90 * system clock.
91 *
92 * When the kernel time is reckoned directly in nanoseconds (NTP_NANO
93 * defined), the time at each tick interrupt is derived directly from
94 * the kernel time variable. When the kernel time is reckoned in
95 * microseconds, (NTP_NANO undefined), the time is derived from the
96 * kernel time variable together with a variable representing the
97 * leftover nanoseconds at the last tick interrupt. In either case, the
98 * current nanosecond time is reckoned from these values plus an
99 * interpolated value derived by the clock routines in another
100 * architecture-specific module. The interpolation can use either a
101 * dedicated counter or a processor cycle counter (PCC) implemented in
102 * some architectures.
103 *
104 * Note that all routines must run at priority splclock or higher.
105 */
106/*
107 * Phase/frequency-lock loop (PLL/FLL) definitions
108 *
109 * The nanosecond clock discipline uses two variable types, time
110 * variables and frequency variables. Both types are represented as 64-
111 * bit fixed-point quantities with the decimal point between two 32-bit
112 * halves. On a 32-bit machine, each half is represented as a single
113 * word and mathematical operations are done using multiple-precision
114 * arithmetic. On a 64-bit machine, ordinary computer arithmetic is
115 * used.
116 *
117 * A time variable is a signed 64-bit fixed-point number in ns and
118 * fraction. It represents the remaining time offset to be amortized
119 * over succeeding tick interrupts. The maximum time offset is about
120 * 0.5 s and the resolution is about 2.3e-10 ns.
121 *
122 * 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3
123 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
124 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
125 * |s s s| ns |
126 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
127 * | fraction |
128 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
129 *
130 * A frequency variable is a signed 64-bit fixed-point number in ns/s
131 * and fraction. It represents the ns and fraction to be added to the
132 * kernel time variable at each second. The maximum frequency offset is
133 * about +-500000 ns/s and the resolution is about 2.3e-10 ns/s.
134 *
135 * 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3
136 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
137 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
138 * |s s s s s s s s s s s s s| ns/s |
139 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
140 * | fraction |
141 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
142 */
143/*
144 * The following variables establish the state of the PLL/FLL and the
145 * residual time and frequency offset of the local clock.
146 */
147#define SHIFT_PLL 4 /* PLL loop gain (shift) */
148#define SHIFT_FLL 2 /* FLL loop gain (shift) */
149
150static int time_state = TIME_OK; /* clock state */
151static int time_status = STA_UNSYNC; /* clock status bits */
152static long time_tai; /* TAI offset (s) */
153static long time_monitor; /* last time offset scaled (ns) */
154static long time_constant; /* poll interval (shift) (s) */
155static long time_precision = 1; /* clock precision (ns) */
156static long time_maxerror = MAXPHASE / 1000; /* maximum error (us) */
157static long time_esterror = MAXPHASE / 1000; /* estimated error (us) */
158static long time_reftime; /* time at last adjustment (s) */
159static l_fp time_offset; /* time offset (ns) */
160static l_fp time_freq; /* frequency offset (ns/s) */
161static l_fp time_adj; /* tick adjust (ns/s) */
162
163static int64_t time_adjtime; /* correction from adjtime(2) (usec) */
164
165#ifdef PPS_SYNC
166/*
167 * The following variables are used when a pulse-per-second (PPS) signal
168 * is available and connected via a modem control lead. They establish
169 * the engineering parameters of the clock discipline loop when
170 * controlled by the PPS signal.
171 */
172#define PPS_FAVG 2 /* min freq avg interval (s) (shift) */
173#define PPS_FAVGDEF 8 /* default freq avg int (s) (shift) */
174#define PPS_FAVGMAX 15 /* max freq avg interval (s) (shift) */
175#define PPS_PAVG 4 /* phase avg interval (s) (shift) */
176#define PPS_VALID 120 /* PPS signal watchdog max (s) */
177#define PPS_MAXWANDER 100000 /* max PPS wander (ns/s) */
178#define PPS_POPCORN 2 /* popcorn spike threshold (shift) */
179
180static struct timespec pps_tf[3]; /* phase median filter */
181static l_fp pps_freq; /* scaled frequency offset (ns/s) */
182static long pps_fcount; /* frequency accumulator */
183static long pps_jitter; /* nominal jitter (ns) */
184static long pps_stabil; /* nominal stability (scaled ns/s) */
185static long pps_lastsec; /* time at last calibration (s) */
186static int pps_valid; /* signal watchdog counter */
187static int pps_shift = PPS_FAVG; /* interval duration (s) (shift) */
188static int pps_shiftmax = PPS_FAVGDEF; /* max interval duration (s) (shift) */
189static int pps_intcnt; /* wander counter */
190
191/*
192 * PPS signal quality monitors
193 */
194static long pps_calcnt; /* calibration intervals */
195static long pps_jitcnt; /* jitter limit exceeded */
196static long pps_stbcnt; /* stability limit exceeded */
197static long pps_errcnt; /* calibration errors */
198#endif /* PPS_SYNC */
199/*
200 * End of phase/frequency-lock loop (PLL/FLL) definitions
201 */
202
203static void ntp_init(void);
204static void hardupdate(long offset);
205static void ntp_gettime1(struct ntptimeval *ntvp);
206static int ntp_is_time_error(void);
207
208static int
209ntp_is_time_error(void)
210{
211 /*
212 * Status word error decode. If any of these conditions occur,
213 * an error is returned, instead of the status word. Most
214 * applications will care only about the fact the system clock
215 * may not be trusted, not about the details.
216 *
217 * Hardware or software error
218 */
219 if ((time_status & (STA_UNSYNC | STA_CLOCKERR)) ||
220
221 /*
222 * PPS signal lost when either time or frequency synchronization
223 * requested
224 */
225 (time_status & (STA_PPSFREQ | STA_PPSTIME) &&
226 !(time_status & STA_PPSSIGNAL)) ||
227
228 /*
229 * PPS jitter exceeded when time synchronization requested
230 */
231 (time_status & STA_PPSTIME &&
232 time_status & STA_PPSJITTER) ||
233
234 /*
235 * PPS wander exceeded or calibration error when frequency
236 * synchronization requested
237 */
238 (time_status & STA_PPSFREQ &&
239 time_status & (STA_PPSWANDER | STA_PPSERROR)))
240 return (1);
241
242 return (0);
243}
244
245static void
246ntp_gettime1(struct ntptimeval *ntvp)
247{
248 struct timespec atv; /* nanosecond time */
249
250 GIANT_REQUIRED;
251
252 nanotime(&atv);
253 ntvp->time.tv_sec = atv.tv_sec;
254 ntvp->time.tv_nsec = atv.tv_nsec;
255 ntvp->maxerror = time_maxerror;
256 ntvp->esterror = time_esterror;
257 ntvp->tai = time_tai;
258 ntvp->time_state = time_state;
259
260 if (ntp_is_time_error())
261 ntvp->time_state = TIME_ERROR;
262}
263
264/*
265 * ntp_gettime() - NTP user application interface
266 *
267 * See the timex.h header file for synopsis and API description. Note that
268 * the TAI offset is returned in the ntvtimeval.tai structure member.
269 */
270#ifndef _SYS_SYSPROTO_H_
271struct ntp_gettime_args {
272 struct ntptimeval *ntvp;
273};
274#endif
275/* ARGSUSED */
276int
277sys_ntp_gettime(struct thread *td, struct ntp_gettime_args *uap)
278{
279 struct ntptimeval ntv;
280
281 mtx_lock(&Giant);
282 ntp_gettime1(&ntv);
283 mtx_unlock(&Giant);
284
285 td->td_retval[0] = ntv.time_state;
286 return (copyout(&ntv, uap->ntvp, sizeof(ntv)));
287}
288
289static int
290ntp_sysctl(SYSCTL_HANDLER_ARGS)
291{
292 struct ntptimeval ntv; /* temporary structure */
293
294 ntp_gettime1(&ntv);
295
296 return (sysctl_handle_opaque(oidp, &ntv, sizeof(ntv), req));
297}
298
299SYSCTL_NODE(_kern, OID_AUTO, ntp_pll, CTLFLAG_RW, 0, "");
300SYSCTL_PROC(_kern_ntp_pll, OID_AUTO, gettime, CTLTYPE_OPAQUE|CTLFLAG_RD,
301 0, sizeof(struct ntptimeval) , ntp_sysctl, "S,ntptimeval", "");
302
303#ifdef PPS_SYNC
| 35
36#include "opt_ntp.h"
37
38#include <sys/param.h>
39#include <sys/systm.h>
40#include <sys/sysproto.h>
41#include <sys/eventhandler.h>
42#include <sys/kernel.h>
43#include <sys/priv.h>
44#include <sys/proc.h>
45#include <sys/lock.h>
46#include <sys/mutex.h>
47#include <sys/time.h>
48#include <sys/timex.h>
49#include <sys/timetc.h>
50#include <sys/timepps.h>
51#include <sys/syscallsubr.h>
52#include <sys/sysctl.h>
53
54#ifdef PPS_SYNC
55FEATURE(pps_sync, "Support usage of external PPS signal by kernel PLL");
56#endif
57
58/*
59 * Single-precision macros for 64-bit machines
60 */
61typedef int64_t l_fp;
62#define L_ADD(v, u) ((v) += (u))
63#define L_SUB(v, u) ((v) -= (u))
64#define L_ADDHI(v, a) ((v) += (int64_t)(a) << 32)
65#define L_NEG(v) ((v) = -(v))
66#define L_RSHIFT(v, n) \
67 do { \
68 if ((v) < 0) \
69 (v) = -(-(v) >> (n)); \
70 else \
71 (v) = (v) >> (n); \
72 } while (0)
73#define L_MPY(v, a) ((v) *= (a))
74#define L_CLR(v) ((v) = 0)
75#define L_ISNEG(v) ((v) < 0)
76#define L_LINT(v, a) ((v) = (int64_t)(a) << 32)
77#define L_GINT(v) ((v) < 0 ? -(-(v) >> 32) : (v) >> 32)
78
79/*
80 * Generic NTP kernel interface
81 *
82 * These routines constitute the Network Time Protocol (NTP) interfaces
83 * for user and daemon application programs. The ntp_gettime() routine
84 * provides the time, maximum error (synch distance) and estimated error
85 * (dispersion) to client user application programs. The ntp_adjtime()
86 * routine is used by the NTP daemon to adjust the system clock to an
87 * externally derived time. The time offset and related variables set by
88 * this routine are used by other routines in this module to adjust the
89 * phase and frequency of the clock discipline loop which controls the
90 * system clock.
91 *
92 * When the kernel time is reckoned directly in nanoseconds (NTP_NANO
93 * defined), the time at each tick interrupt is derived directly from
94 * the kernel time variable. When the kernel time is reckoned in
95 * microseconds, (NTP_NANO undefined), the time is derived from the
96 * kernel time variable together with a variable representing the
97 * leftover nanoseconds at the last tick interrupt. In either case, the
98 * current nanosecond time is reckoned from these values plus an
99 * interpolated value derived by the clock routines in another
100 * architecture-specific module. The interpolation can use either a
101 * dedicated counter or a processor cycle counter (PCC) implemented in
102 * some architectures.
103 *
104 * Note that all routines must run at priority splclock or higher.
105 */
106/*
107 * Phase/frequency-lock loop (PLL/FLL) definitions
108 *
109 * The nanosecond clock discipline uses two variable types, time
110 * variables and frequency variables. Both types are represented as 64-
111 * bit fixed-point quantities with the decimal point between two 32-bit
112 * halves. On a 32-bit machine, each half is represented as a single
113 * word and mathematical operations are done using multiple-precision
114 * arithmetic. On a 64-bit machine, ordinary computer arithmetic is
115 * used.
116 *
117 * A time variable is a signed 64-bit fixed-point number in ns and
118 * fraction. It represents the remaining time offset to be amortized
119 * over succeeding tick interrupts. The maximum time offset is about
120 * 0.5 s and the resolution is about 2.3e-10 ns.
121 *
122 * 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3
123 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
124 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
125 * |s s s| ns |
126 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
127 * | fraction |
128 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
129 *
130 * A frequency variable is a signed 64-bit fixed-point number in ns/s
131 * and fraction. It represents the ns and fraction to be added to the
132 * kernel time variable at each second. The maximum frequency offset is
133 * about +-500000 ns/s and the resolution is about 2.3e-10 ns/s.
134 *
135 * 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3
136 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
137 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
138 * |s s s s s s s s s s s s s| ns/s |
139 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
140 * | fraction |
141 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
142 */
143/*
144 * The following variables establish the state of the PLL/FLL and the
145 * residual time and frequency offset of the local clock.
146 */
147#define SHIFT_PLL 4 /* PLL loop gain (shift) */
148#define SHIFT_FLL 2 /* FLL loop gain (shift) */
149
150static int time_state = TIME_OK; /* clock state */
151static int time_status = STA_UNSYNC; /* clock status bits */
152static long time_tai; /* TAI offset (s) */
153static long time_monitor; /* last time offset scaled (ns) */
154static long time_constant; /* poll interval (shift) (s) */
155static long time_precision = 1; /* clock precision (ns) */
156static long time_maxerror = MAXPHASE / 1000; /* maximum error (us) */
157static long time_esterror = MAXPHASE / 1000; /* estimated error (us) */
158static long time_reftime; /* time at last adjustment (s) */
159static l_fp time_offset; /* time offset (ns) */
160static l_fp time_freq; /* frequency offset (ns/s) */
161static l_fp time_adj; /* tick adjust (ns/s) */
162
163static int64_t time_adjtime; /* correction from adjtime(2) (usec) */
164
165#ifdef PPS_SYNC
166/*
167 * The following variables are used when a pulse-per-second (PPS) signal
168 * is available and connected via a modem control lead. They establish
169 * the engineering parameters of the clock discipline loop when
170 * controlled by the PPS signal.
171 */
172#define PPS_FAVG 2 /* min freq avg interval (s) (shift) */
173#define PPS_FAVGDEF 8 /* default freq avg int (s) (shift) */
174#define PPS_FAVGMAX 15 /* max freq avg interval (s) (shift) */
175#define PPS_PAVG 4 /* phase avg interval (s) (shift) */
176#define PPS_VALID 120 /* PPS signal watchdog max (s) */
177#define PPS_MAXWANDER 100000 /* max PPS wander (ns/s) */
178#define PPS_POPCORN 2 /* popcorn spike threshold (shift) */
179
180static struct timespec pps_tf[3]; /* phase median filter */
181static l_fp pps_freq; /* scaled frequency offset (ns/s) */
182static long pps_fcount; /* frequency accumulator */
183static long pps_jitter; /* nominal jitter (ns) */
184static long pps_stabil; /* nominal stability (scaled ns/s) */
185static long pps_lastsec; /* time at last calibration (s) */
186static int pps_valid; /* signal watchdog counter */
187static int pps_shift = PPS_FAVG; /* interval duration (s) (shift) */
188static int pps_shiftmax = PPS_FAVGDEF; /* max interval duration (s) (shift) */
189static int pps_intcnt; /* wander counter */
190
191/*
192 * PPS signal quality monitors
193 */
194static long pps_calcnt; /* calibration intervals */
195static long pps_jitcnt; /* jitter limit exceeded */
196static long pps_stbcnt; /* stability limit exceeded */
197static long pps_errcnt; /* calibration errors */
198#endif /* PPS_SYNC */
199/*
200 * End of phase/frequency-lock loop (PLL/FLL) definitions
201 */
202
203static void ntp_init(void);
204static void hardupdate(long offset);
205static void ntp_gettime1(struct ntptimeval *ntvp);
206static int ntp_is_time_error(void);
207
208static int
209ntp_is_time_error(void)
210{
211 /*
212 * Status word error decode. If any of these conditions occur,
213 * an error is returned, instead of the status word. Most
214 * applications will care only about the fact the system clock
215 * may not be trusted, not about the details.
216 *
217 * Hardware or software error
218 */
219 if ((time_status & (STA_UNSYNC | STA_CLOCKERR)) ||
220
221 /*
222 * PPS signal lost when either time or frequency synchronization
223 * requested
224 */
225 (time_status & (STA_PPSFREQ | STA_PPSTIME) &&
226 !(time_status & STA_PPSSIGNAL)) ||
227
228 /*
229 * PPS jitter exceeded when time synchronization requested
230 */
231 (time_status & STA_PPSTIME &&
232 time_status & STA_PPSJITTER) ||
233
234 /*
235 * PPS wander exceeded or calibration error when frequency
236 * synchronization requested
237 */
238 (time_status & STA_PPSFREQ &&
239 time_status & (STA_PPSWANDER | STA_PPSERROR)))
240 return (1);
241
242 return (0);
243}
244
245static void
246ntp_gettime1(struct ntptimeval *ntvp)
247{
248 struct timespec atv; /* nanosecond time */
249
250 GIANT_REQUIRED;
251
252 nanotime(&atv);
253 ntvp->time.tv_sec = atv.tv_sec;
254 ntvp->time.tv_nsec = atv.tv_nsec;
255 ntvp->maxerror = time_maxerror;
256 ntvp->esterror = time_esterror;
257 ntvp->tai = time_tai;
258 ntvp->time_state = time_state;
259
260 if (ntp_is_time_error())
261 ntvp->time_state = TIME_ERROR;
262}
263
264/*
265 * ntp_gettime() - NTP user application interface
266 *
267 * See the timex.h header file for synopsis and API description. Note that
268 * the TAI offset is returned in the ntvtimeval.tai structure member.
269 */
270#ifndef _SYS_SYSPROTO_H_
271struct ntp_gettime_args {
272 struct ntptimeval *ntvp;
273};
274#endif
275/* ARGSUSED */
276int
277sys_ntp_gettime(struct thread *td, struct ntp_gettime_args *uap)
278{
279 struct ntptimeval ntv;
280
281 mtx_lock(&Giant);
282 ntp_gettime1(&ntv);
283 mtx_unlock(&Giant);
284
285 td->td_retval[0] = ntv.time_state;
286 return (copyout(&ntv, uap->ntvp, sizeof(ntv)));
287}
288
289static int
290ntp_sysctl(SYSCTL_HANDLER_ARGS)
291{
292 struct ntptimeval ntv; /* temporary structure */
293
294 ntp_gettime1(&ntv);
295
296 return (sysctl_handle_opaque(oidp, &ntv, sizeof(ntv), req));
297}
298
299SYSCTL_NODE(_kern, OID_AUTO, ntp_pll, CTLFLAG_RW, 0, "");
300SYSCTL_PROC(_kern_ntp_pll, OID_AUTO, gettime, CTLTYPE_OPAQUE|CTLFLAG_RD,
301 0, sizeof(struct ntptimeval) , ntp_sysctl, "S,ntptimeval", "");
302
303#ifdef PPS_SYNC
|
311#endif
312
313/*
314 * ntp_adjtime() - NTP daemon application interface
315 *
316 * See the timex.h header file for synopsis and API description. Note that
317 * the timex.constant structure member has a dual purpose to set the time
318 * constant and to set the TAI offset.
319 */
320#ifndef _SYS_SYSPROTO_H_
321struct ntp_adjtime_args {
322 struct timex *tp;
323};
324#endif
325
326int
327sys_ntp_adjtime(struct thread *td, struct ntp_adjtime_args *uap)
328{
329 struct timex ntv; /* temporary structure */
330 long freq; /* frequency ns/s) */
331 int modes; /* mode bits from structure */
332 int s; /* caller priority */
333 int error;
334
335 error = copyin((caddr_t)uap->tp, (caddr_t)&ntv, sizeof(ntv));
336 if (error)
337 return(error);
338
339 /*
340 * Update selected clock variables - only the superuser can
341 * change anything. Note that there is no error checking here on
342 * the assumption the superuser should know what it is doing.
343 * Note that either the time constant or TAI offset are loaded
344 * from the ntv.constant member, depending on the mode bits. If
345 * the STA_PLL bit in the status word is cleared, the state and
346 * status words are reset to the initial values at boot.
347 */
348 mtx_lock(&Giant);
349 modes = ntv.modes;
350 if (modes)
351 error = priv_check(td, PRIV_NTP_ADJTIME);
352 if (error)
353 goto done2;
354 s = splclock();
355 if (modes & MOD_MAXERROR)
356 time_maxerror = ntv.maxerror;
357 if (modes & MOD_ESTERROR)
358 time_esterror = ntv.esterror;
359 if (modes & MOD_STATUS) {
360 if (time_status & STA_PLL && !(ntv.status & STA_PLL)) {
361 time_state = TIME_OK;
362 time_status = STA_UNSYNC;
363#ifdef PPS_SYNC
364 pps_shift = PPS_FAVG;
365#endif /* PPS_SYNC */
366 }
367 time_status &= STA_RONLY;
368 time_status |= ntv.status & ~STA_RONLY;
369 }
370 if (modes & MOD_TIMECONST) {
371 if (ntv.constant < 0)
372 time_constant = 0;
373 else if (ntv.constant > MAXTC)
374 time_constant = MAXTC;
375 else
376 time_constant = ntv.constant;
377 }
378 if (modes & MOD_TAI) {
379 if (ntv.constant > 0) /* XXX zero & negative numbers ? */
380 time_tai = ntv.constant;
381 }
382#ifdef PPS_SYNC
383 if (modes & MOD_PPSMAX) {
384 if (ntv.shift < PPS_FAVG)
385 pps_shiftmax = PPS_FAVG;
386 else if (ntv.shift > PPS_FAVGMAX)
387 pps_shiftmax = PPS_FAVGMAX;
388 else
389 pps_shiftmax = ntv.shift;
390 }
391#endif /* PPS_SYNC */
392 if (modes & MOD_NANO)
393 time_status |= STA_NANO;
394 if (modes & MOD_MICRO)
395 time_status &= ~STA_NANO;
396 if (modes & MOD_CLKB)
397 time_status |= STA_CLK;
398 if (modes & MOD_CLKA)
399 time_status &= ~STA_CLK;
400 if (modes & MOD_FREQUENCY) {
401 freq = (ntv.freq * 1000LL) >> 16;
402 if (freq > MAXFREQ)
403 L_LINT(time_freq, MAXFREQ);
404 else if (freq < -MAXFREQ)
405 L_LINT(time_freq, -MAXFREQ);
406 else {
407 /*
408 * ntv.freq is [PPM * 2^16] = [us/s * 2^16]
409 * time_freq is [ns/s * 2^32]
410 */
411 time_freq = ntv.freq * 1000LL * 65536LL;
412 }
413#ifdef PPS_SYNC
414 pps_freq = time_freq;
415#endif /* PPS_SYNC */
416 }
417 if (modes & MOD_OFFSET) {
418 if (time_status & STA_NANO)
419 hardupdate(ntv.offset);
420 else
421 hardupdate(ntv.offset * 1000);
422 }
423
424 /*
425 * Retrieve all clock variables. Note that the TAI offset is
426 * returned only by ntp_gettime();
427 */
428 if (time_status & STA_NANO)
429 ntv.offset = L_GINT(time_offset);
430 else
431 ntv.offset = L_GINT(time_offset) / 1000; /* XXX rounding ? */
432 ntv.freq = L_GINT((time_freq / 1000LL) << 16);
433 ntv.maxerror = time_maxerror;
434 ntv.esterror = time_esterror;
435 ntv.status = time_status;
436 ntv.constant = time_constant;
437 if (time_status & STA_NANO)
438 ntv.precision = time_precision;
439 else
440 ntv.precision = time_precision / 1000;
441 ntv.tolerance = MAXFREQ * SCALE_PPM;
442#ifdef PPS_SYNC
443 ntv.shift = pps_shift;
444 ntv.ppsfreq = L_GINT((pps_freq / 1000LL) << 16);
445 if (time_status & STA_NANO)
446 ntv.jitter = pps_jitter;
447 else
448 ntv.jitter = pps_jitter / 1000;
449 ntv.stabil = pps_stabil;
450 ntv.calcnt = pps_calcnt;
451 ntv.errcnt = pps_errcnt;
452 ntv.jitcnt = pps_jitcnt;
453 ntv.stbcnt = pps_stbcnt;
454#endif /* PPS_SYNC */
455 splx(s);
456
457 error = copyout((caddr_t)&ntv, (caddr_t)uap->tp, sizeof(ntv));
458 if (error)
459 goto done2;
460
461 if (ntp_is_time_error())
462 td->td_retval[0] = TIME_ERROR;
463 else
464 td->td_retval[0] = time_state;
465
466done2:
467 mtx_unlock(&Giant);
468 return (error);
469}
470
471/*
472 * second_overflow() - called after ntp_tick_adjust()
473 *
474 * This routine is ordinarily called immediately following the above
475 * routine ntp_tick_adjust(). While these two routines are normally
476 * combined, they are separated here only for the purposes of
477 * simulation.
478 */
479void
480ntp_update_second(int64_t *adjustment, time_t *newsec)
481{
482 int tickrate;
483 l_fp ftemp; /* 32/64-bit temporary */
484
485 /*
486 * On rollover of the second both the nanosecond and microsecond
487 * clocks are updated and the state machine cranked as
488 * necessary. The phase adjustment to be used for the next
489 * second is calculated and the maximum error is increased by
490 * the tolerance.
491 */
492 time_maxerror += MAXFREQ / 1000;
493
494 /*
495 * Leap second processing. If in leap-insert state at
496 * the end of the day, the system clock is set back one
497 * second; if in leap-delete state, the system clock is
498 * set ahead one second. The nano_time() routine or
499 * external clock driver will insure that reported time
500 * is always monotonic.
501 */
502 switch (time_state) {
503
504 /*
505 * No warning.
506 */
507 case TIME_OK:
508 if (time_status & STA_INS)
509 time_state = TIME_INS;
510 else if (time_status & STA_DEL)
511 time_state = TIME_DEL;
512 break;
513
514 /*
515 * Insert second 23:59:60 following second
516 * 23:59:59.
517 */
518 case TIME_INS:
519 if (!(time_status & STA_INS))
520 time_state = TIME_OK;
521 else if ((*newsec) % 86400 == 0) {
522 (*newsec)--;
523 time_state = TIME_OOP;
524 time_tai++;
525 }
526 break;
527
528 /*
529 * Delete second 23:59:59.
530 */
531 case TIME_DEL:
532 if (!(time_status & STA_DEL))
533 time_state = TIME_OK;
534 else if (((*newsec) + 1) % 86400 == 0) {
535 (*newsec)++;
536 time_tai--;
537 time_state = TIME_WAIT;
538 }
539 break;
540
541 /*
542 * Insert second in progress.
543 */
544 case TIME_OOP:
545 time_state = TIME_WAIT;
546 break;
547
548 /*
549 * Wait for status bits to clear.
550 */
551 case TIME_WAIT:
552 if (!(time_status & (STA_INS | STA_DEL)))
553 time_state = TIME_OK;
554 }
555
556 /*
557 * Compute the total time adjustment for the next second
558 * in ns. The offset is reduced by a factor depending on
559 * whether the PPS signal is operating. Note that the
560 * value is in effect scaled by the clock frequency,
561 * since the adjustment is added at each tick interrupt.
562 */
563 ftemp = time_offset;
564#ifdef PPS_SYNC
565 /* XXX even if PPS signal dies we should finish adjustment ? */
566 if (time_status & STA_PPSTIME && time_status &
567 STA_PPSSIGNAL)
568 L_RSHIFT(ftemp, pps_shift);
569 else
570 L_RSHIFT(ftemp, SHIFT_PLL + time_constant);
571#else
572 L_RSHIFT(ftemp, SHIFT_PLL + time_constant);
573#endif /* PPS_SYNC */
574 time_adj = ftemp;
575 L_SUB(time_offset, ftemp);
576 L_ADD(time_adj, time_freq);
577
578 /*
579 * Apply any correction from adjtime(2). If more than one second
580 * off we slew at a rate of 5ms/s (5000 PPM) else 500us/s (500PPM)
581 * until the last second is slewed the final < 500 usecs.
582 */
583 if (time_adjtime != 0) {
584 if (time_adjtime > 1000000)
585 tickrate = 5000;
586 else if (time_adjtime < -1000000)
587 tickrate = -5000;
588 else if (time_adjtime > 500)
589 tickrate = 500;
590 else if (time_adjtime < -500)
591 tickrate = -500;
592 else
593 tickrate = time_adjtime;
594 time_adjtime -= tickrate;
595 L_LINT(ftemp, tickrate * 1000);
596 L_ADD(time_adj, ftemp);
597 }
598 *adjustment = time_adj;
599
600#ifdef PPS_SYNC
601 if (pps_valid > 0)
602 pps_valid--;
603 else
604 time_status &= ~STA_PPSSIGNAL;
605#endif /* PPS_SYNC */
606}
607
608/*
609 * ntp_init() - initialize variables and structures
610 *
611 * This routine must be called after the kernel variables hz and tick
612 * are set or changed and before the next tick interrupt. In this
613 * particular implementation, these values are assumed set elsewhere in
614 * the kernel. The design allows the clock frequency and tick interval
615 * to be changed while the system is running. So, this routine should
616 * probably be integrated with the code that does that.
617 */
618static void
619ntp_init()
620{
621
622 /*
623 * The following variables are initialized only at startup. Only
624 * those structures not cleared by the compiler need to be
625 * initialized, and these only in the simulator. In the actual
626 * kernel, any nonzero values here will quickly evaporate.
627 */
628 L_CLR(time_offset);
629 L_CLR(time_freq);
630#ifdef PPS_SYNC
631 pps_tf[0].tv_sec = pps_tf[0].tv_nsec = 0;
632 pps_tf[1].tv_sec = pps_tf[1].tv_nsec = 0;
633 pps_tf[2].tv_sec = pps_tf[2].tv_nsec = 0;
634 pps_fcount = 0;
635 L_CLR(pps_freq);
636#endif /* PPS_SYNC */
637}
638
639SYSINIT(ntpclocks, SI_SUB_CLOCKS, SI_ORDER_MIDDLE, ntp_init, NULL);
640
641/*
642 * hardupdate() - local clock update
643 *
644 * This routine is called by ntp_adjtime() to update the local clock
645 * phase and frequency. The implementation is of an adaptive-parameter,
646 * hybrid phase/frequency-lock loop (PLL/FLL). The routine computes new
647 * time and frequency offset estimates for each call. If the kernel PPS
648 * discipline code is configured (PPS_SYNC), the PPS signal itself
649 * determines the new time offset, instead of the calling argument.
650 * Presumably, calls to ntp_adjtime() occur only when the caller
651 * believes the local clock is valid within some bound (+-128 ms with
652 * NTP). If the caller's time is far different than the PPS time, an
653 * argument will ensue, and it's not clear who will lose.
654 *
655 * For uncompensated quartz crystal oscillators and nominal update
656 * intervals less than 256 s, operation should be in phase-lock mode,
657 * where the loop is disciplined to phase. For update intervals greater
658 * than 1024 s, operation should be in frequency-lock mode, where the
659 * loop is disciplined to frequency. Between 256 s and 1024 s, the mode
660 * is selected by the STA_MODE status bit.
661 */
662static void
663hardupdate(offset)
664 long offset; /* clock offset (ns) */
665{
666 long mtemp;
667 l_fp ftemp;
668
669 /*
670 * Select how the phase is to be controlled and from which
671 * source. If the PPS signal is present and enabled to
672 * discipline the time, the PPS offset is used; otherwise, the
673 * argument offset is used.
674 */
675 if (!(time_status & STA_PLL))
676 return;
677 if (!(time_status & STA_PPSTIME && time_status &
678 STA_PPSSIGNAL)) {
679 if (offset > MAXPHASE)
680 time_monitor = MAXPHASE;
681 else if (offset < -MAXPHASE)
682 time_monitor = -MAXPHASE;
683 else
684 time_monitor = offset;
685 L_LINT(time_offset, time_monitor);
686 }
687
688 /*
689 * Select how the frequency is to be controlled and in which
690 * mode (PLL or FLL). If the PPS signal is present and enabled
691 * to discipline the frequency, the PPS frequency is used;
692 * otherwise, the argument offset is used to compute it.
693 */
694 if (time_status & STA_PPSFREQ && time_status & STA_PPSSIGNAL) {
695 time_reftime = time_second;
696 return;
697 }
698 if (time_status & STA_FREQHOLD || time_reftime == 0)
699 time_reftime = time_second;
700 mtemp = time_second - time_reftime;
701 L_LINT(ftemp, time_monitor);
702 L_RSHIFT(ftemp, (SHIFT_PLL + 2 + time_constant) << 1);
703 L_MPY(ftemp, mtemp);
704 L_ADD(time_freq, ftemp);
705 time_status &= ~STA_MODE;
706 if (mtemp >= MINSEC && (time_status & STA_FLL || mtemp >
707 MAXSEC)) {
708 L_LINT(ftemp, (time_monitor << 4) / mtemp);
709 L_RSHIFT(ftemp, SHIFT_FLL + 4);
710 L_ADD(time_freq, ftemp);
711 time_status |= STA_MODE;
712 }
713 time_reftime = time_second;
714 if (L_GINT(time_freq) > MAXFREQ)
715 L_LINT(time_freq, MAXFREQ);
716 else if (L_GINT(time_freq) < -MAXFREQ)
717 L_LINT(time_freq, -MAXFREQ);
718}
719
720#ifdef PPS_SYNC
721/*
722 * hardpps() - discipline CPU clock oscillator to external PPS signal
723 *
724 * This routine is called at each PPS interrupt in order to discipline
725 * the CPU clock oscillator to the PPS signal. There are two independent
726 * first-order feedback loops, one for the phase, the other for the
727 * frequency. The phase loop measures and grooms the PPS phase offset
728 * and leaves it in a handy spot for the seconds overflow routine. The
729 * frequency loop averages successive PPS phase differences and
730 * calculates the PPS frequency offset, which is also processed by the
731 * seconds overflow routine. The code requires the caller to capture the
732 * time and architecture-dependent hardware counter values in
733 * nanoseconds at the on-time PPS signal transition.
734 *
735 * Note that, on some Unix systems this routine runs at an interrupt
736 * priority level higher than the timer interrupt routine hardclock().
737 * Therefore, the variables used are distinct from the hardclock()
738 * variables, except for the actual time and frequency variables, which
739 * are determined by this routine and updated atomically.
740 */
741void
742hardpps(tsp, nsec)
743 struct timespec *tsp; /* time at PPS */
744 long nsec; /* hardware counter at PPS */
745{
746 long u_sec, u_nsec, v_nsec; /* temps */
747 l_fp ftemp;
748
749 /*
750 * The signal is first processed by a range gate and frequency
751 * discriminator. The range gate rejects noise spikes outside
752 * the range +-500 us. The frequency discriminator rejects input
753 * signals with apparent frequency outside the range 1 +-500
754 * PPM. If two hits occur in the same second, we ignore the
755 * later hit; if not and a hit occurs outside the range gate,
756 * keep the later hit for later comparison, but do not process
757 * it.
758 */
759 time_status |= STA_PPSSIGNAL | STA_PPSJITTER;
760 time_status &= ~(STA_PPSWANDER | STA_PPSERROR);
761 pps_valid = PPS_VALID;
762 u_sec = tsp->tv_sec;
763 u_nsec = tsp->tv_nsec;
764 if (u_nsec >= (NANOSECOND >> 1)) {
765 u_nsec -= NANOSECOND;
766 u_sec++;
767 }
768 v_nsec = u_nsec - pps_tf[0].tv_nsec;
769 if (u_sec == pps_tf[0].tv_sec && v_nsec < NANOSECOND -
770 MAXFREQ)
771 return;
772 pps_tf[2] = pps_tf[1];
773 pps_tf[1] = pps_tf[0];
774 pps_tf[0].tv_sec = u_sec;
775 pps_tf[0].tv_nsec = u_nsec;
776
777 /*
778 * Compute the difference between the current and previous
779 * counter values. If the difference exceeds 0.5 s, assume it
780 * has wrapped around, so correct 1.0 s. If the result exceeds
781 * the tick interval, the sample point has crossed a tick
782 * boundary during the last second, so correct the tick. Very
783 * intricate.
784 */
785 u_nsec = nsec;
786 if (u_nsec > (NANOSECOND >> 1))
787 u_nsec -= NANOSECOND;
788 else if (u_nsec < -(NANOSECOND >> 1))
789 u_nsec += NANOSECOND;
790 pps_fcount += u_nsec;
791 if (v_nsec > MAXFREQ || v_nsec < -MAXFREQ)
792 return;
793 time_status &= ~STA_PPSJITTER;
794
795 /*
796 * A three-stage median filter is used to help denoise the PPS
797 * time. The median sample becomes the time offset estimate; the
798 * difference between the other two samples becomes the time
799 * dispersion (jitter) estimate.
800 */
801 if (pps_tf[0].tv_nsec > pps_tf[1].tv_nsec) {
802 if (pps_tf[1].tv_nsec > pps_tf[2].tv_nsec) {
803 v_nsec = pps_tf[1].tv_nsec; /* 0 1 2 */
804 u_nsec = pps_tf[0].tv_nsec - pps_tf[2].tv_nsec;
805 } else if (pps_tf[2].tv_nsec > pps_tf[0].tv_nsec) {
806 v_nsec = pps_tf[0].tv_nsec; /* 2 0 1 */
807 u_nsec = pps_tf[2].tv_nsec - pps_tf[1].tv_nsec;
808 } else {
809 v_nsec = pps_tf[2].tv_nsec; /* 0 2 1 */
810 u_nsec = pps_tf[0].tv_nsec - pps_tf[1].tv_nsec;
811 }
812 } else {
813 if (pps_tf[1].tv_nsec < pps_tf[2].tv_nsec) {
814 v_nsec = pps_tf[1].tv_nsec; /* 2 1 0 */
815 u_nsec = pps_tf[2].tv_nsec - pps_tf[0].tv_nsec;
816 } else if (pps_tf[2].tv_nsec < pps_tf[0].tv_nsec) {
817 v_nsec = pps_tf[0].tv_nsec; /* 1 0 2 */
818 u_nsec = pps_tf[1].tv_nsec - pps_tf[2].tv_nsec;
819 } else {
820 v_nsec = pps_tf[2].tv_nsec; /* 1 2 0 */
821 u_nsec = pps_tf[1].tv_nsec - pps_tf[0].tv_nsec;
822 }
823 }
824
825 /*
826 * Nominal jitter is due to PPS signal noise and interrupt
827 * latency. If it exceeds the popcorn threshold, the sample is
828 * discarded. otherwise, if so enabled, the time offset is
829 * updated. We can tolerate a modest loss of data here without
830 * much degrading time accuracy.
831 */
832 if (u_nsec > (pps_jitter << PPS_POPCORN)) {
833 time_status |= STA_PPSJITTER;
834 pps_jitcnt++;
835 } else if (time_status & STA_PPSTIME) {
836 time_monitor = -v_nsec;
837 L_LINT(time_offset, time_monitor);
838 }
839 pps_jitter += (u_nsec - pps_jitter) >> PPS_FAVG;
840 u_sec = pps_tf[0].tv_sec - pps_lastsec;
841 if (u_sec < (1 << pps_shift))
842 return;
843
844 /*
845 * At the end of the calibration interval the difference between
846 * the first and last counter values becomes the scaled
847 * frequency. It will later be divided by the length of the
848 * interval to determine the frequency update. If the frequency
849 * exceeds a sanity threshold, or if the actual calibration
850 * interval is not equal to the expected length, the data are
851 * discarded. We can tolerate a modest loss of data here without
852 * much degrading frequency accuracy.
853 */
854 pps_calcnt++;
855 v_nsec = -pps_fcount;
856 pps_lastsec = pps_tf[0].tv_sec;
857 pps_fcount = 0;
858 u_nsec = MAXFREQ << pps_shift;
859 if (v_nsec > u_nsec || v_nsec < -u_nsec || u_sec != (1 <<
860 pps_shift)) {
861 time_status |= STA_PPSERROR;
862 pps_errcnt++;
863 return;
864 }
865
866 /*
867 * Here the raw frequency offset and wander (stability) is
868 * calculated. If the wander is less than the wander threshold
869 * for four consecutive averaging intervals, the interval is
870 * doubled; if it is greater than the threshold for four
871 * consecutive intervals, the interval is halved. The scaled
872 * frequency offset is converted to frequency offset. The
873 * stability metric is calculated as the average of recent
874 * frequency changes, but is used only for performance
875 * monitoring.
876 */
877 L_LINT(ftemp, v_nsec);
878 L_RSHIFT(ftemp, pps_shift);
879 L_SUB(ftemp, pps_freq);
880 u_nsec = L_GINT(ftemp);
881 if (u_nsec > PPS_MAXWANDER) {
882 L_LINT(ftemp, PPS_MAXWANDER);
883 pps_intcnt--;
884 time_status |= STA_PPSWANDER;
885 pps_stbcnt++;
886 } else if (u_nsec < -PPS_MAXWANDER) {
887 L_LINT(ftemp, -PPS_MAXWANDER);
888 pps_intcnt--;
889 time_status |= STA_PPSWANDER;
890 pps_stbcnt++;
891 } else {
892 pps_intcnt++;
893 }
894 if (pps_intcnt >= 4) {
895 pps_intcnt = 4;
896 if (pps_shift < pps_shiftmax) {
897 pps_shift++;
898 pps_intcnt = 0;
899 }
900 } else if (pps_intcnt <= -4 || pps_shift > pps_shiftmax) {
901 pps_intcnt = -4;
902 if (pps_shift > PPS_FAVG) {
903 pps_shift--;
904 pps_intcnt = 0;
905 }
906 }
907 if (u_nsec < 0)
908 u_nsec = -u_nsec;
909 pps_stabil += (u_nsec * SCALE_PPM - pps_stabil) >> PPS_FAVG;
910
911 /*
912 * The PPS frequency is recalculated and clamped to the maximum
913 * MAXFREQ. If enabled, the system clock frequency is updated as
914 * well.
915 */
916 L_ADD(pps_freq, ftemp);
917 u_nsec = L_GINT(pps_freq);
918 if (u_nsec > MAXFREQ)
919 L_LINT(pps_freq, MAXFREQ);
920 else if (u_nsec < -MAXFREQ)
921 L_LINT(pps_freq, -MAXFREQ);
922 if (time_status & STA_PPSFREQ)
923 time_freq = pps_freq;
924}
925#endif /* PPS_SYNC */
926
927#ifndef _SYS_SYSPROTO_H_
928struct adjtime_args {
929 struct timeval *delta;
930 struct timeval *olddelta;
931};
932#endif
933/* ARGSUSED */
934int
935sys_adjtime(struct thread *td, struct adjtime_args *uap)
936{
937 struct timeval delta, olddelta, *deltap;
938 int error;
939
940 if (uap->delta) {
941 error = copyin(uap->delta, &delta, sizeof(delta));
942 if (error)
943 return (error);
944 deltap = δ
945 } else
946 deltap = NULL;
947 error = kern_adjtime(td, deltap, &olddelta);
948 if (uap->olddelta && error == 0)
949 error = copyout(&olddelta, uap->olddelta, sizeof(olddelta));
950 return (error);
951}
952
953int
954kern_adjtime(struct thread *td, struct timeval *delta, struct timeval *olddelta)
955{
956 struct timeval atv;
957 int error;
958
959 mtx_lock(&Giant);
960 if (olddelta) {
961 atv.tv_sec = time_adjtime / 1000000;
962 atv.tv_usec = time_adjtime % 1000000;
963 if (atv.tv_usec < 0) {
964 atv.tv_usec += 1000000;
965 atv.tv_sec--;
966 }
967 *olddelta = atv;
968 }
969 if (delta) {
970 if ((error = priv_check(td, PRIV_ADJTIME))) {
971 mtx_unlock(&Giant);
972 return (error);
973 }
974 time_adjtime = (int64_t)delta->tv_sec * 1000000 +
975 delta->tv_usec;
976 }
977 mtx_unlock(&Giant);
978 return (0);
979}
980
981static struct callout resettodr_callout;
982static int resettodr_period = 1800;
983
984static void
985periodic_resettodr(void *arg __unused)
986{
987
988 if (!ntp_is_time_error()) {
989 mtx_lock(&Giant);
990 resettodr();
991 mtx_unlock(&Giant);
992 }
993 if (resettodr_period > 0)
994 callout_schedule(&resettodr_callout, resettodr_period * hz);
995}
996
997static void
998shutdown_resettodr(void *arg __unused, int howto __unused)
999{
1000
1001 callout_drain(&resettodr_callout);
1002 if (resettodr_period > 0 && !ntp_is_time_error()) {
1003 mtx_lock(&Giant);
1004 resettodr();
1005 mtx_unlock(&Giant);
1006 }
1007}
1008
1009static int
1010sysctl_resettodr_period(SYSCTL_HANDLER_ARGS)
1011{
1012 int error;
1013
1014 error = sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2, req);
1015 if (error || !req->newptr)
1016 return (error);
1017 if (resettodr_period == 0)
1018 callout_stop(&resettodr_callout);
1019 else
1020 callout_reset(&resettodr_callout, resettodr_period * hz,
1021 periodic_resettodr, NULL);
1022 return (0);
1023}
1024
1025SYSCTL_PROC(_machdep, OID_AUTO, rtc_save_period, CTLTYPE_INT|CTLFLAG_RW,
1026 &resettodr_period, 1800, sysctl_resettodr_period, "I",
1027 "Save system time to RTC with this period (in seconds)");
1028TUNABLE_INT("machdep.rtc_save_period", &resettodr_period);
1029
1030static void
1031start_periodic_resettodr(void *arg __unused)
1032{
1033
1034 EVENTHANDLER_REGISTER(shutdown_pre_sync, shutdown_resettodr, NULL,
1035 SHUTDOWN_PRI_FIRST);
1036 callout_init(&resettodr_callout, 1);
1037 if (resettodr_period == 0)
1038 return;
1039 callout_reset(&resettodr_callout, resettodr_period * hz,
1040 periodic_resettodr, NULL);
1041}
1042
1043SYSINIT(periodic_resettodr, SI_SUB_RUN_SCHEDULER, SI_ORDER_MIDDLE,
1044 start_periodic_resettodr, NULL);
| 315#endif
316
317/*
318 * ntp_adjtime() - NTP daemon application interface
319 *
320 * See the timex.h header file for synopsis and API description. Note that
321 * the timex.constant structure member has a dual purpose to set the time
322 * constant and to set the TAI offset.
323 */
324#ifndef _SYS_SYSPROTO_H_
325struct ntp_adjtime_args {
326 struct timex *tp;
327};
328#endif
329
330int
331sys_ntp_adjtime(struct thread *td, struct ntp_adjtime_args *uap)
332{
333 struct timex ntv; /* temporary structure */
334 long freq; /* frequency ns/s) */
335 int modes; /* mode bits from structure */
336 int s; /* caller priority */
337 int error;
338
339 error = copyin((caddr_t)uap->tp, (caddr_t)&ntv, sizeof(ntv));
340 if (error)
341 return(error);
342
343 /*
344 * Update selected clock variables - only the superuser can
345 * change anything. Note that there is no error checking here on
346 * the assumption the superuser should know what it is doing.
347 * Note that either the time constant or TAI offset are loaded
348 * from the ntv.constant member, depending on the mode bits. If
349 * the STA_PLL bit in the status word is cleared, the state and
350 * status words are reset to the initial values at boot.
351 */
352 mtx_lock(&Giant);
353 modes = ntv.modes;
354 if (modes)
355 error = priv_check(td, PRIV_NTP_ADJTIME);
356 if (error)
357 goto done2;
358 s = splclock();
359 if (modes & MOD_MAXERROR)
360 time_maxerror = ntv.maxerror;
361 if (modes & MOD_ESTERROR)
362 time_esterror = ntv.esterror;
363 if (modes & MOD_STATUS) {
364 if (time_status & STA_PLL && !(ntv.status & STA_PLL)) {
365 time_state = TIME_OK;
366 time_status = STA_UNSYNC;
367#ifdef PPS_SYNC
368 pps_shift = PPS_FAVG;
369#endif /* PPS_SYNC */
370 }
371 time_status &= STA_RONLY;
372 time_status |= ntv.status & ~STA_RONLY;
373 }
374 if (modes & MOD_TIMECONST) {
375 if (ntv.constant < 0)
376 time_constant = 0;
377 else if (ntv.constant > MAXTC)
378 time_constant = MAXTC;
379 else
380 time_constant = ntv.constant;
381 }
382 if (modes & MOD_TAI) {
383 if (ntv.constant > 0) /* XXX zero & negative numbers ? */
384 time_tai = ntv.constant;
385 }
386#ifdef PPS_SYNC
387 if (modes & MOD_PPSMAX) {
388 if (ntv.shift < PPS_FAVG)
389 pps_shiftmax = PPS_FAVG;
390 else if (ntv.shift > PPS_FAVGMAX)
391 pps_shiftmax = PPS_FAVGMAX;
392 else
393 pps_shiftmax = ntv.shift;
394 }
395#endif /* PPS_SYNC */
396 if (modes & MOD_NANO)
397 time_status |= STA_NANO;
398 if (modes & MOD_MICRO)
399 time_status &= ~STA_NANO;
400 if (modes & MOD_CLKB)
401 time_status |= STA_CLK;
402 if (modes & MOD_CLKA)
403 time_status &= ~STA_CLK;
404 if (modes & MOD_FREQUENCY) {
405 freq = (ntv.freq * 1000LL) >> 16;
406 if (freq > MAXFREQ)
407 L_LINT(time_freq, MAXFREQ);
408 else if (freq < -MAXFREQ)
409 L_LINT(time_freq, -MAXFREQ);
410 else {
411 /*
412 * ntv.freq is [PPM * 2^16] = [us/s * 2^16]
413 * time_freq is [ns/s * 2^32]
414 */
415 time_freq = ntv.freq * 1000LL * 65536LL;
416 }
417#ifdef PPS_SYNC
418 pps_freq = time_freq;
419#endif /* PPS_SYNC */
420 }
421 if (modes & MOD_OFFSET) {
422 if (time_status & STA_NANO)
423 hardupdate(ntv.offset);
424 else
425 hardupdate(ntv.offset * 1000);
426 }
427
428 /*
429 * Retrieve all clock variables. Note that the TAI offset is
430 * returned only by ntp_gettime();
431 */
432 if (time_status & STA_NANO)
433 ntv.offset = L_GINT(time_offset);
434 else
435 ntv.offset = L_GINT(time_offset) / 1000; /* XXX rounding ? */
436 ntv.freq = L_GINT((time_freq / 1000LL) << 16);
437 ntv.maxerror = time_maxerror;
438 ntv.esterror = time_esterror;
439 ntv.status = time_status;
440 ntv.constant = time_constant;
441 if (time_status & STA_NANO)
442 ntv.precision = time_precision;
443 else
444 ntv.precision = time_precision / 1000;
445 ntv.tolerance = MAXFREQ * SCALE_PPM;
446#ifdef PPS_SYNC
447 ntv.shift = pps_shift;
448 ntv.ppsfreq = L_GINT((pps_freq / 1000LL) << 16);
449 if (time_status & STA_NANO)
450 ntv.jitter = pps_jitter;
451 else
452 ntv.jitter = pps_jitter / 1000;
453 ntv.stabil = pps_stabil;
454 ntv.calcnt = pps_calcnt;
455 ntv.errcnt = pps_errcnt;
456 ntv.jitcnt = pps_jitcnt;
457 ntv.stbcnt = pps_stbcnt;
458#endif /* PPS_SYNC */
459 splx(s);
460
461 error = copyout((caddr_t)&ntv, (caddr_t)uap->tp, sizeof(ntv));
462 if (error)
463 goto done2;
464
465 if (ntp_is_time_error())
466 td->td_retval[0] = TIME_ERROR;
467 else
468 td->td_retval[0] = time_state;
469
470done2:
471 mtx_unlock(&Giant);
472 return (error);
473}
474
475/*
476 * second_overflow() - called after ntp_tick_adjust()
477 *
478 * This routine is ordinarily called immediately following the above
479 * routine ntp_tick_adjust(). While these two routines are normally
480 * combined, they are separated here only for the purposes of
481 * simulation.
482 */
483void
484ntp_update_second(int64_t *adjustment, time_t *newsec)
485{
486 int tickrate;
487 l_fp ftemp; /* 32/64-bit temporary */
488
489 /*
490 * On rollover of the second both the nanosecond and microsecond
491 * clocks are updated and the state machine cranked as
492 * necessary. The phase adjustment to be used for the next
493 * second is calculated and the maximum error is increased by
494 * the tolerance.
495 */
496 time_maxerror += MAXFREQ / 1000;
497
498 /*
499 * Leap second processing. If in leap-insert state at
500 * the end of the day, the system clock is set back one
501 * second; if in leap-delete state, the system clock is
502 * set ahead one second. The nano_time() routine or
503 * external clock driver will insure that reported time
504 * is always monotonic.
505 */
506 switch (time_state) {
507
508 /*
509 * No warning.
510 */
511 case TIME_OK:
512 if (time_status & STA_INS)
513 time_state = TIME_INS;
514 else if (time_status & STA_DEL)
515 time_state = TIME_DEL;
516 break;
517
518 /*
519 * Insert second 23:59:60 following second
520 * 23:59:59.
521 */
522 case TIME_INS:
523 if (!(time_status & STA_INS))
524 time_state = TIME_OK;
525 else if ((*newsec) % 86400 == 0) {
526 (*newsec)--;
527 time_state = TIME_OOP;
528 time_tai++;
529 }
530 break;
531
532 /*
533 * Delete second 23:59:59.
534 */
535 case TIME_DEL:
536 if (!(time_status & STA_DEL))
537 time_state = TIME_OK;
538 else if (((*newsec) + 1) % 86400 == 0) {
539 (*newsec)++;
540 time_tai--;
541 time_state = TIME_WAIT;
542 }
543 break;
544
545 /*
546 * Insert second in progress.
547 */
548 case TIME_OOP:
549 time_state = TIME_WAIT;
550 break;
551
552 /*
553 * Wait for status bits to clear.
554 */
555 case TIME_WAIT:
556 if (!(time_status & (STA_INS | STA_DEL)))
557 time_state = TIME_OK;
558 }
559
560 /*
561 * Compute the total time adjustment for the next second
562 * in ns. The offset is reduced by a factor depending on
563 * whether the PPS signal is operating. Note that the
564 * value is in effect scaled by the clock frequency,
565 * since the adjustment is added at each tick interrupt.
566 */
567 ftemp = time_offset;
568#ifdef PPS_SYNC
569 /* XXX even if PPS signal dies we should finish adjustment ? */
570 if (time_status & STA_PPSTIME && time_status &
571 STA_PPSSIGNAL)
572 L_RSHIFT(ftemp, pps_shift);
573 else
574 L_RSHIFT(ftemp, SHIFT_PLL + time_constant);
575#else
576 L_RSHIFT(ftemp, SHIFT_PLL + time_constant);
577#endif /* PPS_SYNC */
578 time_adj = ftemp;
579 L_SUB(time_offset, ftemp);
580 L_ADD(time_adj, time_freq);
581
582 /*
583 * Apply any correction from adjtime(2). If more than one second
584 * off we slew at a rate of 5ms/s (5000 PPM) else 500us/s (500PPM)
585 * until the last second is slewed the final < 500 usecs.
586 */
587 if (time_adjtime != 0) {
588 if (time_adjtime > 1000000)
589 tickrate = 5000;
590 else if (time_adjtime < -1000000)
591 tickrate = -5000;
592 else if (time_adjtime > 500)
593 tickrate = 500;
594 else if (time_adjtime < -500)
595 tickrate = -500;
596 else
597 tickrate = time_adjtime;
598 time_adjtime -= tickrate;
599 L_LINT(ftemp, tickrate * 1000);
600 L_ADD(time_adj, ftemp);
601 }
602 *adjustment = time_adj;
603
604#ifdef PPS_SYNC
605 if (pps_valid > 0)
606 pps_valid--;
607 else
608 time_status &= ~STA_PPSSIGNAL;
609#endif /* PPS_SYNC */
610}
611
612/*
613 * ntp_init() - initialize variables and structures
614 *
615 * This routine must be called after the kernel variables hz and tick
616 * are set or changed and before the next tick interrupt. In this
617 * particular implementation, these values are assumed set elsewhere in
618 * the kernel. The design allows the clock frequency and tick interval
619 * to be changed while the system is running. So, this routine should
620 * probably be integrated with the code that does that.
621 */
622static void
623ntp_init()
624{
625
626 /*
627 * The following variables are initialized only at startup. Only
628 * those structures not cleared by the compiler need to be
629 * initialized, and these only in the simulator. In the actual
630 * kernel, any nonzero values here will quickly evaporate.
631 */
632 L_CLR(time_offset);
633 L_CLR(time_freq);
634#ifdef PPS_SYNC
635 pps_tf[0].tv_sec = pps_tf[0].tv_nsec = 0;
636 pps_tf[1].tv_sec = pps_tf[1].tv_nsec = 0;
637 pps_tf[2].tv_sec = pps_tf[2].tv_nsec = 0;
638 pps_fcount = 0;
639 L_CLR(pps_freq);
640#endif /* PPS_SYNC */
641}
642
643SYSINIT(ntpclocks, SI_SUB_CLOCKS, SI_ORDER_MIDDLE, ntp_init, NULL);
644
645/*
646 * hardupdate() - local clock update
647 *
648 * This routine is called by ntp_adjtime() to update the local clock
649 * phase and frequency. The implementation is of an adaptive-parameter,
650 * hybrid phase/frequency-lock loop (PLL/FLL). The routine computes new
651 * time and frequency offset estimates for each call. If the kernel PPS
652 * discipline code is configured (PPS_SYNC), the PPS signal itself
653 * determines the new time offset, instead of the calling argument.
654 * Presumably, calls to ntp_adjtime() occur only when the caller
655 * believes the local clock is valid within some bound (+-128 ms with
656 * NTP). If the caller's time is far different than the PPS time, an
657 * argument will ensue, and it's not clear who will lose.
658 *
659 * For uncompensated quartz crystal oscillators and nominal update
660 * intervals less than 256 s, operation should be in phase-lock mode,
661 * where the loop is disciplined to phase. For update intervals greater
662 * than 1024 s, operation should be in frequency-lock mode, where the
663 * loop is disciplined to frequency. Between 256 s and 1024 s, the mode
664 * is selected by the STA_MODE status bit.
665 */
666static void
667hardupdate(offset)
668 long offset; /* clock offset (ns) */
669{
670 long mtemp;
671 l_fp ftemp;
672
673 /*
674 * Select how the phase is to be controlled and from which
675 * source. If the PPS signal is present and enabled to
676 * discipline the time, the PPS offset is used; otherwise, the
677 * argument offset is used.
678 */
679 if (!(time_status & STA_PLL))
680 return;
681 if (!(time_status & STA_PPSTIME && time_status &
682 STA_PPSSIGNAL)) {
683 if (offset > MAXPHASE)
684 time_monitor = MAXPHASE;
685 else if (offset < -MAXPHASE)
686 time_monitor = -MAXPHASE;
687 else
688 time_monitor = offset;
689 L_LINT(time_offset, time_monitor);
690 }
691
692 /*
693 * Select how the frequency is to be controlled and in which
694 * mode (PLL or FLL). If the PPS signal is present and enabled
695 * to discipline the frequency, the PPS frequency is used;
696 * otherwise, the argument offset is used to compute it.
697 */
698 if (time_status & STA_PPSFREQ && time_status & STA_PPSSIGNAL) {
699 time_reftime = time_second;
700 return;
701 }
702 if (time_status & STA_FREQHOLD || time_reftime == 0)
703 time_reftime = time_second;
704 mtemp = time_second - time_reftime;
705 L_LINT(ftemp, time_monitor);
706 L_RSHIFT(ftemp, (SHIFT_PLL + 2 + time_constant) << 1);
707 L_MPY(ftemp, mtemp);
708 L_ADD(time_freq, ftemp);
709 time_status &= ~STA_MODE;
710 if (mtemp >= MINSEC && (time_status & STA_FLL || mtemp >
711 MAXSEC)) {
712 L_LINT(ftemp, (time_monitor << 4) / mtemp);
713 L_RSHIFT(ftemp, SHIFT_FLL + 4);
714 L_ADD(time_freq, ftemp);
715 time_status |= STA_MODE;
716 }
717 time_reftime = time_second;
718 if (L_GINT(time_freq) > MAXFREQ)
719 L_LINT(time_freq, MAXFREQ);
720 else if (L_GINT(time_freq) < -MAXFREQ)
721 L_LINT(time_freq, -MAXFREQ);
722}
723
724#ifdef PPS_SYNC
725/*
726 * hardpps() - discipline CPU clock oscillator to external PPS signal
727 *
728 * This routine is called at each PPS interrupt in order to discipline
729 * the CPU clock oscillator to the PPS signal. There are two independent
730 * first-order feedback loops, one for the phase, the other for the
731 * frequency. The phase loop measures and grooms the PPS phase offset
732 * and leaves it in a handy spot for the seconds overflow routine. The
733 * frequency loop averages successive PPS phase differences and
734 * calculates the PPS frequency offset, which is also processed by the
735 * seconds overflow routine. The code requires the caller to capture the
736 * time and architecture-dependent hardware counter values in
737 * nanoseconds at the on-time PPS signal transition.
738 *
739 * Note that, on some Unix systems this routine runs at an interrupt
740 * priority level higher than the timer interrupt routine hardclock().
741 * Therefore, the variables used are distinct from the hardclock()
742 * variables, except for the actual time and frequency variables, which
743 * are determined by this routine and updated atomically.
744 */
745void
746hardpps(tsp, nsec)
747 struct timespec *tsp; /* time at PPS */
748 long nsec; /* hardware counter at PPS */
749{
750 long u_sec, u_nsec, v_nsec; /* temps */
751 l_fp ftemp;
752
753 /*
754 * The signal is first processed by a range gate and frequency
755 * discriminator. The range gate rejects noise spikes outside
756 * the range +-500 us. The frequency discriminator rejects input
757 * signals with apparent frequency outside the range 1 +-500
758 * PPM. If two hits occur in the same second, we ignore the
759 * later hit; if not and a hit occurs outside the range gate,
760 * keep the later hit for later comparison, but do not process
761 * it.
762 */
763 time_status |= STA_PPSSIGNAL | STA_PPSJITTER;
764 time_status &= ~(STA_PPSWANDER | STA_PPSERROR);
765 pps_valid = PPS_VALID;
766 u_sec = tsp->tv_sec;
767 u_nsec = tsp->tv_nsec;
768 if (u_nsec >= (NANOSECOND >> 1)) {
769 u_nsec -= NANOSECOND;
770 u_sec++;
771 }
772 v_nsec = u_nsec - pps_tf[0].tv_nsec;
773 if (u_sec == pps_tf[0].tv_sec && v_nsec < NANOSECOND -
774 MAXFREQ)
775 return;
776 pps_tf[2] = pps_tf[1];
777 pps_tf[1] = pps_tf[0];
778 pps_tf[0].tv_sec = u_sec;
779 pps_tf[0].tv_nsec = u_nsec;
780
781 /*
782 * Compute the difference between the current and previous
783 * counter values. If the difference exceeds 0.5 s, assume it
784 * has wrapped around, so correct 1.0 s. If the result exceeds
785 * the tick interval, the sample point has crossed a tick
786 * boundary during the last second, so correct the tick. Very
787 * intricate.
788 */
789 u_nsec = nsec;
790 if (u_nsec > (NANOSECOND >> 1))
791 u_nsec -= NANOSECOND;
792 else if (u_nsec < -(NANOSECOND >> 1))
793 u_nsec += NANOSECOND;
794 pps_fcount += u_nsec;
795 if (v_nsec > MAXFREQ || v_nsec < -MAXFREQ)
796 return;
797 time_status &= ~STA_PPSJITTER;
798
799 /*
800 * A three-stage median filter is used to help denoise the PPS
801 * time. The median sample becomes the time offset estimate; the
802 * difference between the other two samples becomes the time
803 * dispersion (jitter) estimate.
804 */
805 if (pps_tf[0].tv_nsec > pps_tf[1].tv_nsec) {
806 if (pps_tf[1].tv_nsec > pps_tf[2].tv_nsec) {
807 v_nsec = pps_tf[1].tv_nsec; /* 0 1 2 */
808 u_nsec = pps_tf[0].tv_nsec - pps_tf[2].tv_nsec;
809 } else if (pps_tf[2].tv_nsec > pps_tf[0].tv_nsec) {
810 v_nsec = pps_tf[0].tv_nsec; /* 2 0 1 */
811 u_nsec = pps_tf[2].tv_nsec - pps_tf[1].tv_nsec;
812 } else {
813 v_nsec = pps_tf[2].tv_nsec; /* 0 2 1 */
814 u_nsec = pps_tf[0].tv_nsec - pps_tf[1].tv_nsec;
815 }
816 } else {
817 if (pps_tf[1].tv_nsec < pps_tf[2].tv_nsec) {
818 v_nsec = pps_tf[1].tv_nsec; /* 2 1 0 */
819 u_nsec = pps_tf[2].tv_nsec - pps_tf[0].tv_nsec;
820 } else if (pps_tf[2].tv_nsec < pps_tf[0].tv_nsec) {
821 v_nsec = pps_tf[0].tv_nsec; /* 1 0 2 */
822 u_nsec = pps_tf[1].tv_nsec - pps_tf[2].tv_nsec;
823 } else {
824 v_nsec = pps_tf[2].tv_nsec; /* 1 2 0 */
825 u_nsec = pps_tf[1].tv_nsec - pps_tf[0].tv_nsec;
826 }
827 }
828
829 /*
830 * Nominal jitter is due to PPS signal noise and interrupt
831 * latency. If it exceeds the popcorn threshold, the sample is
832 * discarded. otherwise, if so enabled, the time offset is
833 * updated. We can tolerate a modest loss of data here without
834 * much degrading time accuracy.
835 */
836 if (u_nsec > (pps_jitter << PPS_POPCORN)) {
837 time_status |= STA_PPSJITTER;
838 pps_jitcnt++;
839 } else if (time_status & STA_PPSTIME) {
840 time_monitor = -v_nsec;
841 L_LINT(time_offset, time_monitor);
842 }
843 pps_jitter += (u_nsec - pps_jitter) >> PPS_FAVG;
844 u_sec = pps_tf[0].tv_sec - pps_lastsec;
845 if (u_sec < (1 << pps_shift))
846 return;
847
848 /*
849 * At the end of the calibration interval the difference between
850 * the first and last counter values becomes the scaled
851 * frequency. It will later be divided by the length of the
852 * interval to determine the frequency update. If the frequency
853 * exceeds a sanity threshold, or if the actual calibration
854 * interval is not equal to the expected length, the data are
855 * discarded. We can tolerate a modest loss of data here without
856 * much degrading frequency accuracy.
857 */
858 pps_calcnt++;
859 v_nsec = -pps_fcount;
860 pps_lastsec = pps_tf[0].tv_sec;
861 pps_fcount = 0;
862 u_nsec = MAXFREQ << pps_shift;
863 if (v_nsec > u_nsec || v_nsec < -u_nsec || u_sec != (1 <<
864 pps_shift)) {
865 time_status |= STA_PPSERROR;
866 pps_errcnt++;
867 return;
868 }
869
870 /*
871 * Here the raw frequency offset and wander (stability) is
872 * calculated. If the wander is less than the wander threshold
873 * for four consecutive averaging intervals, the interval is
874 * doubled; if it is greater than the threshold for four
875 * consecutive intervals, the interval is halved. The scaled
876 * frequency offset is converted to frequency offset. The
877 * stability metric is calculated as the average of recent
878 * frequency changes, but is used only for performance
879 * monitoring.
880 */
881 L_LINT(ftemp, v_nsec);
882 L_RSHIFT(ftemp, pps_shift);
883 L_SUB(ftemp, pps_freq);
884 u_nsec = L_GINT(ftemp);
885 if (u_nsec > PPS_MAXWANDER) {
886 L_LINT(ftemp, PPS_MAXWANDER);
887 pps_intcnt--;
888 time_status |= STA_PPSWANDER;
889 pps_stbcnt++;
890 } else if (u_nsec < -PPS_MAXWANDER) {
891 L_LINT(ftemp, -PPS_MAXWANDER);
892 pps_intcnt--;
893 time_status |= STA_PPSWANDER;
894 pps_stbcnt++;
895 } else {
896 pps_intcnt++;
897 }
898 if (pps_intcnt >= 4) {
899 pps_intcnt = 4;
900 if (pps_shift < pps_shiftmax) {
901 pps_shift++;
902 pps_intcnt = 0;
903 }
904 } else if (pps_intcnt <= -4 || pps_shift > pps_shiftmax) {
905 pps_intcnt = -4;
906 if (pps_shift > PPS_FAVG) {
907 pps_shift--;
908 pps_intcnt = 0;
909 }
910 }
911 if (u_nsec < 0)
912 u_nsec = -u_nsec;
913 pps_stabil += (u_nsec * SCALE_PPM - pps_stabil) >> PPS_FAVG;
914
915 /*
916 * The PPS frequency is recalculated and clamped to the maximum
917 * MAXFREQ. If enabled, the system clock frequency is updated as
918 * well.
919 */
920 L_ADD(pps_freq, ftemp);
921 u_nsec = L_GINT(pps_freq);
922 if (u_nsec > MAXFREQ)
923 L_LINT(pps_freq, MAXFREQ);
924 else if (u_nsec < -MAXFREQ)
925 L_LINT(pps_freq, -MAXFREQ);
926 if (time_status & STA_PPSFREQ)
927 time_freq = pps_freq;
928}
929#endif /* PPS_SYNC */
930
931#ifndef _SYS_SYSPROTO_H_
932struct adjtime_args {
933 struct timeval *delta;
934 struct timeval *olddelta;
935};
936#endif
937/* ARGSUSED */
938int
939sys_adjtime(struct thread *td, struct adjtime_args *uap)
940{
941 struct timeval delta, olddelta, *deltap;
942 int error;
943
944 if (uap->delta) {
945 error = copyin(uap->delta, &delta, sizeof(delta));
946 if (error)
947 return (error);
948 deltap = δ
949 } else
950 deltap = NULL;
951 error = kern_adjtime(td, deltap, &olddelta);
952 if (uap->olddelta && error == 0)
953 error = copyout(&olddelta, uap->olddelta, sizeof(olddelta));
954 return (error);
955}
956
957int
958kern_adjtime(struct thread *td, struct timeval *delta, struct timeval *olddelta)
959{
960 struct timeval atv;
961 int error;
962
963 mtx_lock(&Giant);
964 if (olddelta) {
965 atv.tv_sec = time_adjtime / 1000000;
966 atv.tv_usec = time_adjtime % 1000000;
967 if (atv.tv_usec < 0) {
968 atv.tv_usec += 1000000;
969 atv.tv_sec--;
970 }
971 *olddelta = atv;
972 }
973 if (delta) {
974 if ((error = priv_check(td, PRIV_ADJTIME))) {
975 mtx_unlock(&Giant);
976 return (error);
977 }
978 time_adjtime = (int64_t)delta->tv_sec * 1000000 +
979 delta->tv_usec;
980 }
981 mtx_unlock(&Giant);
982 return (0);
983}
984
985static struct callout resettodr_callout;
986static int resettodr_period = 1800;
987
988static void
989periodic_resettodr(void *arg __unused)
990{
991
992 if (!ntp_is_time_error()) {
993 mtx_lock(&Giant);
994 resettodr();
995 mtx_unlock(&Giant);
996 }
997 if (resettodr_period > 0)
998 callout_schedule(&resettodr_callout, resettodr_period * hz);
999}
1000
1001static void
1002shutdown_resettodr(void *arg __unused, int howto __unused)
1003{
1004
1005 callout_drain(&resettodr_callout);
1006 if (resettodr_period > 0 && !ntp_is_time_error()) {
1007 mtx_lock(&Giant);
1008 resettodr();
1009 mtx_unlock(&Giant);
1010 }
1011}
1012
1013static int
1014sysctl_resettodr_period(SYSCTL_HANDLER_ARGS)
1015{
1016 int error;
1017
1018 error = sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2, req);
1019 if (error || !req->newptr)
1020 return (error);
1021 if (resettodr_period == 0)
1022 callout_stop(&resettodr_callout);
1023 else
1024 callout_reset(&resettodr_callout, resettodr_period * hz,
1025 periodic_resettodr, NULL);
1026 return (0);
1027}
1028
1029SYSCTL_PROC(_machdep, OID_AUTO, rtc_save_period, CTLTYPE_INT|CTLFLAG_RW,
1030 &resettodr_period, 1800, sysctl_resettodr_period, "I",
1031 "Save system time to RTC with this period (in seconds)");
1032TUNABLE_INT("machdep.rtc_save_period", &resettodr_period);
1033
1034static void
1035start_periodic_resettodr(void *arg __unused)
1036{
1037
1038 EVENTHANDLER_REGISTER(shutdown_pre_sync, shutdown_resettodr, NULL,
1039 SHUTDOWN_PRI_FIRST);
1040 callout_init(&resettodr_callout, 1);
1041 if (resettodr_period == 0)
1042 return;
1043 callout_reset(&resettodr_callout, resettodr_period * hz,
1044 periodic_resettodr, NULL);
1045}
1046
1047SYSINIT(periodic_resettodr, SI_SUB_RUN_SCHEDULER, SI_ORDER_MIDDLE,
1048 start_periodic_resettodr, NULL);
|