1 /********************************************* 1 /*****************************************************************************
2 * 2 * *
3 * Copyright (c) David L. Mills 1993 3 * Copyright (c) David L. Mills 1993 *
4 * 4 * *
5 * Permission to use, copy, modify, and distri 5 * Permission to use, copy, modify, and distribute this software and its *
6 * documentation for any purpose and without f 6 * documentation for any purpose and without fee is hereby granted, provided *
7 * that the above copyright notice appears in 7 * that the above copyright notice appears in all copies and that both the *
8 * copyright notice and this permission notice 8 * copyright notice and this permission notice appear in supporting *
9 * documentation, and that the name University 9 * documentation, and that the name University of Delaware not be used in *
10 * advertising or publicity pertaining to dist 10 * advertising or publicity pertaining to distribution of the software *
11 * without specific, written prior permission. 11 * without specific, written prior permission. The University of Delaware *
12 * makes no representations about the suitabil 12 * makes no representations about the suitability this software for any *
13 * purpose. It is provided "as is" without ex 13 * purpose. It is provided "as is" without express or implied warranty. *
14 * 14 * *
15 ********************************************* 15 *****************************************************************************/
16 16
17 /* 17 /*
18 * Modification history timex.h 18 * Modification history timex.h
19 * 19 *
20 * 29 Dec 97 Russell King 20 * 29 Dec 97 Russell King
21 * Moved CLOCK_TICK_RATE, CLOCK_TICK_FACT 21 * Moved CLOCK_TICK_RATE, CLOCK_TICK_FACTOR and FINETUNE to asm/timex.h
22 * for ARM machines 22 * for ARM machines
23 * 23 *
24 * 9 Jan 97 Adrian Sun 24 * 9 Jan 97 Adrian Sun
25 * Shifted LATCH define to allow access t 25 * Shifted LATCH define to allow access to alpha machines.
26 * 26 *
27 * 26 Sep 94 David L. Mills 27 * 26 Sep 94 David L. Mills
28 * Added defines for hybrid phase/frequen 28 * Added defines for hybrid phase/frequency-lock loop.
29 * 29 *
30 * 19 Mar 94 David L. Mills 30 * 19 Mar 94 David L. Mills
31 * Moved defines from kernel routines to 31 * Moved defines from kernel routines to header file and added new
32 * defines for PPS phase-lock loop. 32 * defines for PPS phase-lock loop.
33 * 33 *
34 * 20 Feb 94 David L. Mills 34 * 20 Feb 94 David L. Mills
35 * Revised status codes and structures fo 35 * Revised status codes and structures for external clock and PPS
36 * signal discipline. 36 * signal discipline.
37 * 37 *
38 * 28 Nov 93 David L. Mills 38 * 28 Nov 93 David L. Mills
39 * Adjusted parameters to improve stabili 39 * Adjusted parameters to improve stability and increase poll
40 * interval. 40 * interval.
41 * 41 *
42 * 17 Sep 93 David L. Mills 42 * 17 Sep 93 David L. Mills
43 * Created file $NTP/include/sys/timex.h 43 * Created file $NTP/include/sys/timex.h
44 * 07 Oct 93 Torsten Duwe 44 * 07 Oct 93 Torsten Duwe
45 * Derived linux/timex.h 45 * Derived linux/timex.h
46 * 1995-08-13 Torsten Duwe 46 * 1995-08-13 Torsten Duwe
47 * kernel PLL updated to 1994-12-13 specs 47 * kernel PLL updated to 1994-12-13 specs (rfc-1589)
48 * 1997-08-30 Ulrich Windl 48 * 1997-08-30 Ulrich Windl
49 * Added new constant NTP_PHASE_LIMIT 49 * Added new constant NTP_PHASE_LIMIT
50 * 2004-08-12 Christoph Lameter <<
51 * Reworked time interpolation logic <<
52 */ 50 */
53 #ifndef _LINUX_TIMEX_H 51 #ifndef _LINUX_TIMEX_H
54 #define _LINUX_TIMEX_H 52 #define _LINUX_TIMEX_H
55 53
56 #include <uapi/linux/timex.h> !! 54 #include <linux/config.h>
57 <<
58 #define ADJ_ADJTIME 0x8000 /* swi <<
59 #define ADJ_OFFSET_SINGLESHOT 0x0001 /* old <<
60 #define ADJ_OFFSET_READONLY 0x2000 /* rea <<
61 #include <linux/compiler.h> 55 #include <linux/compiler.h>
62 #include <linux/types.h> <<
63 #include <linux/param.h> <<
64 <<
65 unsigned long random_get_entropy_fallback(void <<
66 56
67 #include <asm/timex.h> !! 57 #include <asm/param.h>
68 58
69 #ifndef random_get_entropy <<
70 /* 59 /*
71 * The random_get_entropy() function is used b !! 60 * The following defines establish the engineering parameters of the PLL
72 * in order to extract entropy via the relativ !! 61 * model. The HZ variable establishes the timer interrupt frequency, 100 Hz
73 * when an interrupt takes places versus a hig !! 62 * for the SunOS kernel, 256 Hz for the Ultrix kernel and 1024 Hz for the
74 * timing source or cycle counter. Since it w !! 63 * OSF/1 kernel. The SHIFT_HZ define expresses the same value as the
75 * single interrupt, it must have a very low c !! 64 * nearest power of two in order to avoid hardware multiply operations.
76 * <<
77 * By default we use get_cycles() for this pur <<
78 * architectures may override this in their as <<
79 * If a given arch does not have get_cycles(), <<
80 * using random_get_entropy_fallback(). <<
81 */ 65 */
82 #ifdef get_cycles !! 66 #if HZ >= 12 && HZ < 24
83 #define random_get_entropy() ((unsigned lon !! 67 # define SHIFT_HZ 4
>> 68 #elif HZ >= 24 && HZ < 48
>> 69 # define SHIFT_HZ 5
>> 70 #elif HZ >= 48 && HZ < 96
>> 71 # define SHIFT_HZ 6
>> 72 #elif HZ >= 96 && HZ < 192
>> 73 # define SHIFT_HZ 7
>> 74 #elif HZ >= 192 && HZ < 384
>> 75 # define SHIFT_HZ 8
>> 76 #elif HZ >= 384 && HZ < 768
>> 77 # define SHIFT_HZ 9
>> 78 #elif HZ >= 768 && HZ < 1536
>> 79 # define SHIFT_HZ 10
84 #else 80 #else
85 #define random_get_entropy() random_get_ent !! 81 # error You lose.
86 #endif <<
87 #endif 82 #endif
88 83
89 /* 84 /*
90 * SHIFT_PLL is used as a dampening factor to !! 85 * SHIFT_KG and SHIFT_KF establish the damping of the PLL and are chosen
91 * adjust the frequency correction for a given !! 86 * for a slightly underdamped convergence characteristic. SHIFT_KH
92 * It also used in dampening the offset correc !! 87 * establishes the damping of the FLL and is chosen by wisdom and black
93 * much of the current value in time_offset we !! 88 * art.
94 * second. Changing this value changes the sti !! 89 *
95 * adjustment code. A lower value makes it mor !! 90 * MAXTC establishes the maximum time constant of the PLL. With the
96 * NTP convergence time. A higher value makes !! 91 * SHIFT_KG and SHIFT_KF values given and a time constant range from
97 * convergence time, but making the clock more !! 92 * zero to MAXTC, the PLL will converge in 15 minutes to 16 hours,
98 * !! 93 * respectively.
99 * In David Mills' nanokernel reference implem !! 94 */
100 * However this seems to increase convergence !! 95 #define SHIFT_KG 6 /* phase factor (shift) */
101 * !! 96 #define SHIFT_KF 16 /* PLL frequency factor (shift) */
102 * https://lists.ntp.org/pipermail/hackers/200 !! 97 #define SHIFT_KH 2 /* FLL frequency factor (shift) */
103 * !! 98 #define MAXTC 6 /* maximum time constant (shift) */
104 * In the above mailing list discussion, it se <<
105 * was appropriate for other Unix systems with <<
106 * SHIFT_PLL should be decreased as HZ increas <<
107 * clock steering implementation is HZ indepen <<
108 * <<
109 * Through experimentation, a SHIFT_PLL value <<
110 * for fast convergence (very similar to the N <<
111 * v2.6.19), with good clock stability. <<
112 * <<
113 * <<
114 * SHIFT_FLL is used as a dampening factor to <<
115 * adjust the frequency correction for a given <<
116 * In David Mills' nanokernel reference implem <<
117 * <<
118 * MAXTC establishes the maximum time constant <<
119 */ <<
120 #define SHIFT_PLL 2 /* PLL frequen <<
121 #define SHIFT_FLL 2 /* FLL frequen <<
122 #define MAXTC 10 /* maximum tim <<
123 99
124 /* 100 /*
>> 101 * The SHIFT_SCALE define establishes the decimal point of the time_phase
>> 102 * variable which serves as an extension to the low-order bits of the
>> 103 * system clock variable. The SHIFT_UPDATE define establishes the decimal
>> 104 * point of the time_offset variable which represents the current offset
>> 105 * with respect to standard time. The FINENSEC define represents 1 nsec in
>> 106 * scaled units.
>> 107 *
125 * SHIFT_USEC defines the scaling (shift) of t 108 * SHIFT_USEC defines the scaling (shift) of the time_freq and
126 * time_tolerance variables, which represent t 109 * time_tolerance variables, which represent the current frequency
127 * offset and maximum frequency tolerance. 110 * offset and maximum frequency tolerance.
>> 111 *
>> 112 * FINENSEC is 1 ns in SHIFT_UPDATE units of the time_phase variable.
128 */ 113 */
>> 114 #define SHIFT_SCALE 22 /* phase scale (shift) */
>> 115 #define SHIFT_UPDATE (SHIFT_KG + MAXTC) /* time offset scale (shift) */
129 #define SHIFT_USEC 16 /* frequency o 116 #define SHIFT_USEC 16 /* frequency offset scale (shift) */
130 #define PPM_SCALE ((s64)NSEC_PER_USEC << (NTP_ !! 117 #define FINENSEC (1L << (SHIFT_SCALE - 10)) /* ~1 ns in phase units */
131 #define PPM_SCALE_INV_SHIFT 19 !! 118
132 #define PPM_SCALE_INV ((1LL << (PPM_SCALE_INV_ !! 119 #define MAXPHASE 512000L /* max phase error (us) */
133 PPM_SCALE + 1) !! 120 #define MAXFREQ (512L << SHIFT_USEC) /* max frequency error (ppm) */
134 !! 121 #define MAXTIME (200L << PPS_AVG) /* max PPS error (jitter) (200 us) */
135 #define MAXPHASE 500000000L /* max phase e !! 122 #define MINSEC 16L /* min interval between updates (s) */
136 #define MAXFREQ 500000 /* max frequen !! 123 #define MAXSEC 1200L /* max interval between updates (s) */
137 #define MAXFREQ_SCALED ((s64)MAXFREQ << NTP_SC !! 124 #define NTP_PHASE_LIMIT (MAXPHASE << 5) /* beyond max. dispersion */
138 #define MINSEC 256 /* min interva <<
139 #define MAXSEC 2048 /* max interva <<
140 #define NTP_PHASE_LIMIT ((MAXPHASE / NSEC_PER_ <<
141 125
142 /* 126 /*
>> 127 * The following defines are used only if a pulse-per-second (PPS)
>> 128 * signal is available and connected via a modem control lead, such as
>> 129 * produced by the optional ppsclock feature incorporated in the Sun
>> 130 * asynch driver. They establish the design parameters of the frequency-
>> 131 * lock loop used to discipline the CPU clock oscillator to the PPS
>> 132 * signal.
>> 133 *
>> 134 * PPS_AVG is the averaging factor for the frequency loop, as well as
>> 135 * the time and frequency dispersion.
>> 136 *
>> 137 * PPS_SHIFT and PPS_SHIFTMAX specify the minimum and maximum
>> 138 * calibration intervals, respectively, in seconds as a power of two.
>> 139 *
>> 140 * PPS_VALID is the maximum interval before the PPS signal is considered
>> 141 * invalid and protocol updates used directly instead.
>> 142 *
>> 143 * MAXGLITCH is the maximum interval before a time offset of more than
>> 144 * MAXTIME is believed.
>> 145 */
>> 146 #define PPS_AVG 2 /* pps averaging constant (shift) */
>> 147 #define PPS_SHIFT 2 /* min interval duration (s) (shift) */
>> 148 #define PPS_SHIFTMAX 8 /* max interval duration (s) (shift) */
>> 149 #define PPS_VALID 120 /* pps signal watchdog max (s) */
>> 150 #define MAXGLITCH 30 /* pps signal glitch max (s) */
>> 151
>> 152 /*
>> 153 * Pick up the architecture specific timex specifications
>> 154 */
>> 155 #include <asm/timex.h>
>> 156
>> 157 /* LATCH is used in the interval timer and ftape setup. */
>> 158 #define LATCH ((CLOCK_TICK_RATE + HZ/2) / HZ) /* For divider */
>> 159
>> 160 /* Suppose we want to devide two numbers NOM and DEN: NOM/DEN, the we can
>> 161 * improve accuracy by shifting LSH bits, hence calculating:
>> 162 * (NOM << LSH) / DEN
>> 163 * This however means trouble for large NOM, because (NOM << LSH) may no
>> 164 * longer fit in 32 bits. The following way of calculating this gives us
>> 165 * some slack, under the following conditions:
>> 166 * - (NOM / DEN) fits in (32 - LSH) bits.
>> 167 * - (NOM % DEN) fits in (32 - LSH) bits.
>> 168 */
>> 169 #define SH_DIV(NOM,DEN,LSH) ( ((NOM / DEN) << LSH) \
>> 170 + (((NOM % DEN) << LSH) + DEN / 2) / DEN)
>> 171
>> 172 /* HZ is the requested value. ACTHZ is actual HZ ("<< 8" is for accuracy) */
>> 173 #define ACTHZ (SH_DIV (CLOCK_TICK_RATE, LATCH, 8))
>> 174
>> 175 /* TICK_NSEC is the time between ticks in nsec assuming real ACTHZ */
>> 176 #define TICK_NSEC (SH_DIV (1000000UL * 1000, ACTHZ, 8))
>> 177
>> 178 /* TICK_USEC is the time between ticks in usec assuming fake USER_HZ */
>> 179 #define TICK_USEC ((1000000UL + USER_HZ/2) / USER_HZ)
>> 180
>> 181 /* TICK_USEC_TO_NSEC is the time between ticks in nsec assuming real ACTHZ and */
>> 182 /* a value TUSEC for TICK_USEC (can be set bij adjtimex) */
>> 183 #define TICK_USEC_TO_NSEC(TUSEC) (SH_DIV (TUSEC * USER_HZ * 1000, ACTHZ, 8))
>> 184
>> 185
>> 186 #include <linux/time.h>
>> 187 /*
>> 188 * syscall interface - used (mainly by NTP daemon)
>> 189 * to discipline kernel clock oscillator
>> 190 */
>> 191 struct timex {
>> 192 unsigned int modes; /* mode selector */
>> 193 long offset; /* time offset (usec) */
>> 194 long freq; /* frequency offset (scaled ppm) */
>> 195 long maxerror; /* maximum error (usec) */
>> 196 long esterror; /* estimated error (usec) */
>> 197 int status; /* clock command/status */
>> 198 long constant; /* pll time constant */
>> 199 long precision; /* clock precision (usec) (read only) */
>> 200 long tolerance; /* clock frequency tolerance (ppm)
>> 201 * (read only)
>> 202 */
>> 203 struct timeval time; /* (read only) */
>> 204 long tick; /* (modified) usecs between clock ticks */
>> 205
>> 206 long ppsfreq; /* pps frequency (scaled ppm) (ro) */
>> 207 long jitter; /* pps jitter (us) (ro) */
>> 208 int shift; /* interval duration (s) (shift) (ro) */
>> 209 long stabil; /* pps stability (scaled ppm) (ro) */
>> 210 long jitcnt; /* jitter limit exceeded (ro) */
>> 211 long calcnt; /* calibration intervals (ro) */
>> 212 long errcnt; /* calibration errors (ro) */
>> 213 long stbcnt; /* stability limit exceeded (ro) */
>> 214
>> 215 int :32; int :32; int :32; int :32;
>> 216 int :32; int :32; int :32; int :32;
>> 217 int :32; int :32; int :32; int :32;
>> 218 };
>> 219
>> 220 /*
>> 221 * Mode codes (timex.mode)
>> 222 */
>> 223 #define ADJ_OFFSET 0x0001 /* time offset */
>> 224 #define ADJ_FREQUENCY 0x0002 /* frequency offset */
>> 225 #define ADJ_MAXERROR 0x0004 /* maximum time error */
>> 226 #define ADJ_ESTERROR 0x0008 /* estimated time error */
>> 227 #define ADJ_STATUS 0x0010 /* clock status */
>> 228 #define ADJ_TIMECONST 0x0020 /* pll time constant */
>> 229 #define ADJ_TICK 0x4000 /* tick value */
>> 230 #define ADJ_OFFSET_SINGLESHOT 0x8001 /* old-fashioned adjtime */
>> 231
>> 232 /* xntp 3.4 compatibility names */
>> 233 #define MOD_OFFSET ADJ_OFFSET
>> 234 #define MOD_FREQUENCY ADJ_FREQUENCY
>> 235 #define MOD_MAXERROR ADJ_MAXERROR
>> 236 #define MOD_ESTERROR ADJ_ESTERROR
>> 237 #define MOD_STATUS ADJ_STATUS
>> 238 #define MOD_TIMECONST ADJ_TIMECONST
>> 239 #define MOD_CLKB ADJ_TICK
>> 240 #define MOD_CLKA ADJ_OFFSET_SINGLESHOT /* 0x8000 in original */
>> 241
>> 242
>> 243 /*
>> 244 * Status codes (timex.status)
>> 245 */
>> 246 #define STA_PLL 0x0001 /* enable PLL updates (rw) */
>> 247 #define STA_PPSFREQ 0x0002 /* enable PPS freq discipline (rw) */
>> 248 #define STA_PPSTIME 0x0004 /* enable PPS time discipline (rw) */
>> 249 #define STA_FLL 0x0008 /* select frequency-lock mode (rw) */
>> 250
>> 251 #define STA_INS 0x0010 /* insert leap (rw) */
>> 252 #define STA_DEL 0x0020 /* delete leap (rw) */
>> 253 #define STA_UNSYNC 0x0040 /* clock unsynchronized (rw) */
>> 254 #define STA_FREQHOLD 0x0080 /* hold frequency (rw) */
>> 255
>> 256 #define STA_PPSSIGNAL 0x0100 /* PPS signal present (ro) */
>> 257 #define STA_PPSJITTER 0x0200 /* PPS signal jitter exceeded (ro) */
>> 258 #define STA_PPSWANDER 0x0400 /* PPS signal wander exceeded (ro) */
>> 259 #define STA_PPSERROR 0x0800 /* PPS signal calibration error (ro) */
>> 260
>> 261 #define STA_CLOCKERR 0x1000 /* clock hardware fault (ro) */
>> 262
>> 263 #define STA_RONLY (STA_PPSSIGNAL | STA_PPSJITTER | STA_PPSWANDER | \
>> 264 STA_PPSERROR | STA_CLOCKERR) /* read-only bits */
>> 265
>> 266 /*
>> 267 * Clock states (time_state)
>> 268 */
>> 269 #define TIME_OK 0 /* clock synchronized, no leap second */
>> 270 #define TIME_INS 1 /* insert leap second */
>> 271 #define TIME_DEL 2 /* delete leap second */
>> 272 #define TIME_OOP 3 /* leap second in progress */
>> 273 #define TIME_WAIT 4 /* leap second has occurred */
>> 274 #define TIME_ERROR 5 /* clock not synchronized */
>> 275 #define TIME_BAD TIME_ERROR /* bw compat */
>> 276
>> 277 #ifdef __KERNEL__
>> 278 /*
143 * kernel variables 279 * kernel variables
144 * Note: maximum error = NTP sync distance = d !! 280 * Note: maximum error = NTP synch distance = dispersion + delay / 2;
145 * estimated error = NTP dispersion. 281 * estimated error = NTP dispersion.
146 */ 282 */
147 extern unsigned long tick_usec; /* USE 283 extern unsigned long tick_usec; /* USER_HZ period (usec) */
148 extern unsigned long tick_nsec; /* SHI !! 284 extern unsigned long tick_nsec; /* ACTHZ period (nsec) */
>> 285 extern int tickadj; /* amount of adjustment per tick */
149 286
150 /* Required to safely shift negative values */ !! 287 /*
151 #define shift_right(x, s) ({ \ !! 288 * phase-lock loop variables
152 __typeof__(x) __x = (x); \ !! 289 */
153 __typeof__(s) __s = (s); \ !! 290 extern int time_state; /* clock status */
154 __x < 0 ? -(-__x >> __s) : __x >> __s; !! 291 extern int time_status; /* clock synchronization status bits */
155 }) !! 292 extern long time_offset; /* time adjustment (us) */
156 !! 293 extern long time_constant; /* pll time constant */
157 #define NTP_SCALE_SHIFT 32 !! 294 extern long time_tolerance; /* frequency tolerance (ppm) */
>> 295 extern long time_precision; /* clock precision (us) */
>> 296 extern long time_maxerror; /* maximum error */
>> 297 extern long time_esterror; /* estimated error */
>> 298
>> 299 extern long time_phase; /* phase offset (scaled us) */
>> 300 extern long time_freq; /* frequency offset (scaled ppm) */
>> 301 extern long time_adj; /* tick adjust (scaled 1 / HZ) */
>> 302 extern long time_reftime; /* time at last adjustment (s) */
>> 303
>> 304 extern long time_adjust; /* The amount of adjtime left */
>> 305 extern long time_next_adjust; /* Value for time_adjust at next tick */
>> 306
>> 307 /* interface variables pps->timer interrupt */
>> 308 extern long pps_offset; /* pps time offset (us) */
>> 309 extern long pps_jitter; /* time dispersion (jitter) (us) */
>> 310 extern long pps_freq; /* frequency offset (scaled ppm) */
>> 311 extern long pps_stabil; /* frequency dispersion (scaled ppm) */
>> 312 extern long pps_valid; /* pps signal watchdog counter */
>> 313
>> 314 /* interface variables pps->adjtimex */
>> 315 extern int pps_shift; /* interval duration (s) (shift) */
>> 316 extern long pps_jitcnt; /* jitter limit exceeded */
>> 317 extern long pps_calcnt; /* calibration intervals */
>> 318 extern long pps_errcnt; /* calibration errors */
>> 319 extern long pps_stbcnt; /* stability limit exceeded */
>> 320
>> 321 #ifdef CONFIG_TIME_INTERPOLATION
>> 322
>> 323 struct time_interpolator {
>> 324 /* cache-hot stuff first: */
>> 325 unsigned long (*get_offset) (void);
>> 326 void (*update) (long);
>> 327 void (*reset) (void);
>> 328
>> 329 /* cache-cold stuff follows here: */
>> 330 struct time_interpolator *next;
>> 331 unsigned long frequency; /* frequency in counts/second */
>> 332 long drift; /* drift in parts-per-million (or -1) */
>> 333 };
>> 334
>> 335 extern volatile unsigned long last_nsec_offset;
>> 336 #ifndef __HAVE_ARCH_CMPXCHG
>> 337 extern spin_lock_t last_nsec_offset_lock;
>> 338 #endif
>> 339 extern struct time_interpolator *time_interpolator;
158 340
159 #define NTP_INTERVAL_FREQ (HZ) !! 341 extern void register_time_interpolator(struct time_interpolator *);
160 #define NTP_INTERVAL_LENGTH (NSEC_PER_SEC/NTP_ !! 342 extern void unregister_time_interpolator(struct time_interpolator *);
161 343
162 extern int do_adjtimex(struct __kernel_timex * !! 344 /* Called with xtime WRITE-lock acquired. */
163 extern int do_clock_adjtime(const clockid_t wh !! 345 static inline void
>> 346 time_interpolator_update(long delta_nsec)
>> 347 {
>> 348 struct time_interpolator *ti = time_interpolator;
>> 349
>> 350 if (last_nsec_offset > 0) {
>> 351 #ifdef __HAVE_ARCH_CMPXCHG
>> 352 unsigned long new, old;
>> 353
>> 354 do {
>> 355 old = last_nsec_offset;
>> 356 if (old > delta_nsec)
>> 357 new = old - delta_nsec;
>> 358 else
>> 359 new = 0;
>> 360 } while (cmpxchg(&last_nsec_offset, old, new) != old);
>> 361 #else
>> 362 /*
>> 363 * This really hurts, because it serializes gettimeofday(), but without an
>> 364 * atomic single-word compare-and-exchange, there isn't all that much else
>> 365 * we can do.
>> 366 */
>> 367 spin_lock(&last_nsec_offset_lock);
>> 368 {
>> 369 last_nsec_offset -= min(last_nsec_offset, delta_nsec);
>> 370 }
>> 371 spin_unlock(&last_nsec_offset_lock);
>> 372 #endif
>> 373 }
164 374
165 extern void hardpps(const struct timespec64 *, !! 375 if (ti)
>> 376 (*ti->update)(delta_nsec);
>> 377 }
>> 378
>> 379 /* Called with xtime WRITE-lock acquired. */
>> 380 static inline void
>> 381 time_interpolator_reset(void)
>> 382 {
>> 383 struct time_interpolator *ti = time_interpolator;
>> 384
>> 385 last_nsec_offset = 0;
>> 386 if (ti)
>> 387 (*ti->reset)();
>> 388 }
>> 389
>> 390 /* Called with xtime READ-lock acquired. */
>> 391 static inline unsigned long
>> 392 time_interpolator_get_offset(void)
>> 393 {
>> 394 struct time_interpolator *ti = time_interpolator;
>> 395 if (ti)
>> 396 return (*ti->get_offset)();
>> 397 return last_nsec_offset;
>> 398 }
>> 399
>> 400 #else /* !CONFIG_TIME_INTERPOLATION */
>> 401
>> 402 static inline void
>> 403 time_interpolator_update(long delta_nsec)
>> 404 {
>> 405 }
>> 406
>> 407 static inline void
>> 408 time_interpolator_reset(void)
>> 409 {
>> 410 }
>> 411
>> 412 static inline unsigned long
>> 413 time_interpolator_get_offset(void)
>> 414 {
>> 415 return 0;
>> 416 }
166 417
167 int read_current_timer(unsigned long *timer_va !! 418 #endif /* !CONFIG_TIME_INTERPOLATION */
168 419
169 /* The clock frequency of the i8253/i8254 PIT !! 420 #endif /* KERNEL */
170 #define PIT_TICK_RATE 1193182ul <<
171 421
172 #endif /* LINUX_TIMEX_H */ 422 #endif /* LINUX_TIMEX_H */
173 423
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