1/***************************************************************************** 2 * * 3 * Copyright (c) David L. Mills 1993 * 4 * * 5 * Permission to use, copy, modify, and distribute this software and its * 6 * documentation for any purpose and without fee is hereby granted, provided * 7 * that the above copyright notice appears in all copies and that both the * 8 * copyright notice and this permission notice appear in supporting * 9 * documentation, and that the name University of Delaware not be used in * 10 * advertising or publicity pertaining to distribution of the software * 11 * without specific, written prior permission. The University of Delaware * 12 * makes no representations about the suitability this software for any * 13 * purpose. It is provided "as is" without express or implied warranty. * 14 * * 15 *****************************************************************************/ 16 17/* 18 * Modification history timex.h 19 * 20 * 29 Dec 97 Russell King 21 * Moved CLOCK_TICK_RATE, CLOCK_TICK_FACTOR and FINETUNE to asm/timex.h 22 * for ARM machines 23 * 24 * 9 Jan 97 Adrian Sun 25 * Shifted LATCH define to allow access to alpha machines. 26 * 27 * 26 Sep 94 David L. Mills 28 * Added defines for hybrid phase/frequency-lock loop. 29 * 30 * 19 Mar 94 David L. Mills 31 * Moved defines from kernel routines to header file and added new 32 * defines for PPS phase-lock loop. 33 * 34 * 20 Feb 94 David L. Mills 35 * Revised status codes and structures for external clock and PPS 36 * signal discipline. 37 * 38 * 28 Nov 93 David L. Mills 39 * Adjusted parameters to improve stability and increase poll 40 * interval. 41 * 42 * 17 Sep 93 David L. Mills 43 * Created file $NTP/include/sys/timex.h 44 * 07 Oct 93 Torsten Duwe 45 * Derived linux/timex.h 46 * 1995-08-13 Torsten Duwe 47 * kernel PLL updated to 1994-12-13 specs (rfc-1589) 48 * 1997-08-30 Ulrich Windl 49 * Added new constant NTP_PHASE_LIMIT 50 * 2004-08-12 Christoph Lameter 51 * Reworked time interpolation logic 52 */ 53#ifndef _LINUX_TIMEX_H 54#define _LINUX_TIMEX_H 55 56#include <linux/compiler.h> 57#include <linux/time.h> 58 59#include <asm/param.h> 60 61/* 62 * SHIFT_KG and SHIFT_KF establish the damping of the PLL and are chosen 63 * for a slightly underdamped convergence characteristic. SHIFT_KH 64 * establishes the damping of the FLL and is chosen by wisdom and black 65 * art. 66 * 67 * MAXTC establishes the maximum time constant of the PLL. With the 68 * SHIFT_KG and SHIFT_KF values given and a time constant range from 69 * zero to MAXTC, the PLL will converge in 15 minutes to 16 hours, 70 * respectively. 71 */ 72#define SHIFT_PLL 4 /* PLL frequency factor (shift) */ 73#define SHIFT_FLL 2 /* FLL frequency factor (shift) */ 74#define MAXTC 10 /* maximum time constant (shift) */ 75 76/* 77 * The SHIFT_UPDATE define establishes the decimal point of the 78 * time_offset variable which represents the current offset with 79 * respect to standard time. 80 * 81 * SHIFT_USEC defines the scaling (shift) of the time_freq and 82 * time_tolerance variables, which represent the current frequency 83 * offset and maximum frequency tolerance. 84 */ 85#define SHIFT_UPDATE (SHIFT_HZ + 1) /* time offset scale (shift) */ 86#define SHIFT_USEC 16 /* frequency offset scale (shift) */ 87#define SHIFT_NSEC 12 /* kernel frequency offset scale */ 88 89#define MAXPHASE 512000L /* max phase error (us) */ 90#define MAXFREQ (512L << SHIFT_USEC) /* max frequency error (ppm) */ 91#define MAXFREQ_NSEC (512000L << SHIFT_NSEC) /* max frequency error (ppb) */ 92#define MINSEC 256 /* min interval between updates (s) */ 93#define MAXSEC 2048 /* max interval between updates (s) */ 94#define NTP_PHASE_LIMIT (MAXPHASE << 5) /* beyond max. dispersion */ 95 96/* 97 * syscall interface - used (mainly by NTP daemon) 98 * to discipline kernel clock oscillator 99 */ 100struct timex { 101 unsigned int modes; /* mode selector */ 102 long offset; /* time offset (usec) */ 103 long freq; /* frequency offset (scaled ppm) */ 104 long maxerror; /* maximum error (usec) */ 105 long esterror; /* estimated error (usec) */ 106 int status; /* clock command/status */ 107 long constant; /* pll time constant */ 108 long precision; /* clock precision (usec) (read only) */ 109 long tolerance; /* clock frequency tolerance (ppm) 110 * (read only) 111 */ 112 struct timeval time; /* (read only) */ 113 long tick; /* (modified) usecs between clock ticks */ 114 115 long ppsfreq; /* pps frequency (scaled ppm) (ro) */ 116 long jitter; /* pps jitter (us) (ro) */ 117 int shift; /* interval duration (s) (shift) (ro) */ 118 long stabil; /* pps stability (scaled ppm) (ro) */ 119 long jitcnt; /* jitter limit exceeded (ro) */ 120 long calcnt; /* calibration intervals (ro) */ 121 long errcnt; /* calibration errors (ro) */ 122 long stbcnt; /* stability limit exceeded (ro) */ 123 124 int :32; int :32; int :32; int :32; 125 int :32; int :32; int :32; int :32; 126 int :32; int :32; int :32; int :32; 127}; 128 129/* 130 * Mode codes (timex.mode) 131 */ 132#define ADJ_OFFSET 0x0001 /* time offset */ 133#define ADJ_FREQUENCY 0x0002 /* frequency offset */ 134#define ADJ_MAXERROR 0x0004 /* maximum time error */ 135#define ADJ_ESTERROR 0x0008 /* estimated time error */ 136#define ADJ_STATUS 0x0010 /* clock status */ 137#define ADJ_TIMECONST 0x0020 /* pll time constant */ 138#define ADJ_TICK 0x4000 /* tick value */ 139#define ADJ_OFFSET_SINGLESHOT 0x8001 /* old-fashioned adjtime */ 140#define ADJ_OFFSET_SS_READ 0xa001 /* read-only adjtime */ 141 142/* xntp 3.4 compatibility names */ 143#define MOD_OFFSET ADJ_OFFSET 144#define MOD_FREQUENCY ADJ_FREQUENCY 145#define MOD_MAXERROR ADJ_MAXERROR 146#define MOD_ESTERROR ADJ_ESTERROR 147#define MOD_STATUS ADJ_STATUS 148#define MOD_TIMECONST ADJ_TIMECONST 149#define MOD_CLKB ADJ_TICK 150#define MOD_CLKA ADJ_OFFSET_SINGLESHOT /* 0x8000 in original */ 151 152 153/* 154 * Status codes (timex.status) 155 */ 156#define STA_PLL 0x0001 /* enable PLL updates (rw) */ 157#define STA_PPSFREQ 0x0002 /* enable PPS freq discipline (rw) */ 158#define STA_PPSTIME 0x0004 /* enable PPS time discipline (rw) */ 159#define STA_FLL 0x0008 /* select frequency-lock mode (rw) */ 160 161#define STA_INS 0x0010 /* insert leap (rw) */ 162#define STA_DEL 0x0020 /* delete leap (rw) */ 163#define STA_UNSYNC 0x0040 /* clock unsynchronized (rw) */ 164#define STA_FREQHOLD 0x0080 /* hold frequency (rw) */ 165 166#define STA_PPSSIGNAL 0x0100 /* PPS signal present (ro) */ 167#define STA_PPSJITTER 0x0200 /* PPS signal jitter exceeded (ro) */ 168#define STA_PPSWANDER 0x0400 /* PPS signal wander exceeded (ro) */ 169#define STA_PPSERROR 0x0800 /* PPS signal calibration error (ro) */ 170 171#define STA_CLOCKERR 0x1000 /* clock hardware fault (ro) */ 172 173#define STA_RONLY (STA_PPSSIGNAL | STA_PPSJITTER | STA_PPSWANDER | \ 174 STA_PPSERROR | STA_CLOCKERR) /* read-only bits */ 175 176/* 177 * Clock states (time_state) 178 */ 179#define TIME_OK 0 /* clock synchronized, no leap second */ 180#define TIME_INS 1 /* insert leap second */ 181#define TIME_DEL 2 /* delete leap second */ 182#define TIME_OOP 3 /* leap second in progress */ 183#define TIME_WAIT 4 /* leap second has occurred */ 184#define TIME_ERROR 5 /* clock not synchronized */ 185#define TIME_BAD TIME_ERROR /* bw compat */ 186 187#ifdef __KERNEL__ 188#include <asm/timex.h> 189 190/* 191 * kernel variables 192 * Note: maximum error = NTP synch distance = dispersion + delay / 2; 193 * estimated error = NTP dispersion. 194 */ 195extern unsigned long tick_usec; /* USER_HZ period (usec) */ 196extern unsigned long tick_nsec; /* ACTHZ period (nsec) */ 197extern int tickadj; /* amount of adjustment per tick */ 198 199/* 200 * phase-lock loop variables 201 */ 202extern int time_status; /* clock synchronization status bits */ 203extern long time_maxerror; /* maximum error */ 204extern long time_esterror; /* estimated error */ 205 206extern long time_freq; /* frequency offset (scaled ppm) */ 207 208extern long time_adjust; /* The amount of adjtime left */ 209 210extern void ntp_clear(void); 211 212/** 213 * ntp_synced - Returns 1 if the NTP status is not UNSYNC 214 * 215 */ 216static inline int ntp_synced(void) 217{ 218 return !(time_status & STA_UNSYNC); 219} 220 221/* Required to safely shift negative values */ 222#define shift_right(x, s) ({ \ 223 __typeof__(x) __x = (x); \ 224 __typeof__(s) __s = (s); \ 225 __x < 0 ? -(-__x >> __s) : __x >> __s; \ 226}) 227 228#define TICK_LENGTH_SHIFT 32 229 230#ifdef CONFIG_NO_HZ 231#define NTP_INTERVAL_FREQ (2) 232#else 233#define NTP_INTERVAL_FREQ (HZ) 234#endif 235#define NTP_INTERVAL_LENGTH (NSEC_PER_SEC/NTP_INTERVAL_FREQ) 236 237/* Returns how long ticks are at present, in ns / 2^(SHIFT_SCALE-10). */ 238extern u64 current_tick_length(void); 239 240extern void second_overflow(void); 241extern void update_ntp_one_tick(void); 242extern int do_adjtimex(struct timex *); 243 244/* Don't use! Compatibility define for existing users. */ 245#define tickadj (500/HZ ? : 1) 246 247#endif /* KERNEL */ 248 249#endif /* LINUX_TIMEX_H */ 250