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/time.h> 57 58 #include <asm/param.h> 59 60 #define NTP_API 4 /* NTP API version */ 61 62 /* 63 * SHIFT_KG and SHIFT_KF establish the damping of the PLL and are chosen 64 * for a slightly underdamped convergence characteristic. SHIFT_KH 65 * establishes the damping of the FLL and is chosen by wisdom and black 66 * art. 67 * 68 * MAXTC establishes the maximum time constant of the PLL. With the 69 * SHIFT_KG and SHIFT_KF values given and a time constant range from 70 * zero to MAXTC, the PLL will converge in 15 minutes to 16 hours, 71 * respectively. 72 */ 73 #define SHIFT_PLL 4 /* PLL frequency factor (shift) */ 74 #define SHIFT_FLL 2 /* FLL frequency factor (shift) */ 75 #define MAXTC 10 /* maximum time constant (shift) */ 76 77 /* 78 * SHIFT_USEC defines the scaling (shift) of the time_freq and 79 * time_tolerance variables, which represent the current frequency 80 * offset and maximum frequency tolerance. 81 */ 82 #define SHIFT_USEC 16 /* frequency offset scale (shift) */ 83 #define PPM_SCALE (NSEC_PER_USEC << (NTP_SCALE_SHIFT - SHIFT_USEC)) 84 #define PPM_SCALE_INV_SHIFT 20 85 #define PPM_SCALE_INV ((1ll << (PPM_SCALE_INV_SHIFT + NTP_SCALE_SHIFT)) / \ 86 PPM_SCALE + 1) 87 88 #define MAXPHASE 500000000l /* max phase error (ns) */ 89 #define MAXFREQ 500000 /* max frequency error (ns/s) */ 90 #define MAXFREQ_SCALED ((s64)MAXFREQ << NTP_SCALE_SHIFT) 91 #define MINSEC 256 /* min interval between updates (s) */ 92 #define MAXSEC 2048 /* max interval between updates (s) */ 93 #define NTP_PHASE_LIMIT ((MAXPHASE / NSEC_PER_USEC) << 5) /* beyond max. dispersion */ 94 95 /* 96 * syscall interface - used (mainly by NTP daemon) 97 * to discipline kernel clock oscillator 98 */ 99 struct timex { 100 unsigned int modes; /* mode selector */ 101 long offset; /* time offset (usec) */ 102 long freq; /* frequency offset (scaled ppm) */ 103 long maxerror; /* maximum error (usec) */ 104 long esterror; /* estimated error (usec) */ 105 int status; /* clock command/status */ 106 long constant; /* pll time constant */ 107 long precision; /* clock precision (usec) (read only) */ 108 long tolerance; /* clock frequency tolerance (ppm) 109 * (read only) 110 */ 111 struct timeval time; /* (read only) */ 112 long tick; /* (modified) usecs between clock ticks */ 113 114 long ppsfreq; /* pps frequency (scaled ppm) (ro) */ 115 long jitter; /* pps jitter (us) (ro) */ 116 int shift; /* interval duration (s) (shift) (ro) */ 117 long stabil; /* pps stability (scaled ppm) (ro) */ 118 long jitcnt; /* jitter limit exceeded (ro) */ 119 long calcnt; /* calibration intervals (ro) */ 120 long errcnt; /* calibration errors (ro) */ 121 long stbcnt; /* stability limit exceeded (ro) */ 122 123 int tai; /* TAI offset (ro) */ 124 125 int :32; int :32; int :32; int :32; 126 int :32; int :32; int :32; int :32; 127 int :32; int :32; int :32; 128 }; 129 130 /* 131 * Mode codes (timex.mode) 132 */ 133 #define ADJ_OFFSET 0x0001 /* time offset */ 134 #define ADJ_FREQUENCY 0x0002 /* frequency offset */ 135 #define ADJ_MAXERROR 0x0004 /* maximum time error */ 136 #define ADJ_ESTERROR 0x0008 /* estimated time error */ 137 #define ADJ_STATUS 0x0010 /* clock status */ 138 #define ADJ_TIMECONST 0x0020 /* pll time constant */ 139 #define ADJ_TAI 0x0080 /* set TAI offset */ 140 #define ADJ_MICRO 0x1000 /* select microsecond resolution */ 141 #define ADJ_NANO 0x2000 /* select nanosecond resolution */ 142 #define ADJ_TICK 0x4000 /* tick value */ 143 #define ADJ_OFFSET_SINGLESHOT 0x8001 /* old-fashioned adjtime */ 144 #define ADJ_OFFSET_SS_READ 0xa001 /* read-only adjtime */ 145 146 /* xntp 3.4 compatibility names */ 147 #define MOD_OFFSET ADJ_OFFSET 148 #define MOD_FREQUENCY ADJ_FREQUENCY 149 #define MOD_MAXERROR ADJ_MAXERROR 150 #define MOD_ESTERROR ADJ_ESTERROR 151 #define MOD_STATUS ADJ_STATUS 152 #define MOD_TIMECONST ADJ_TIMECONST 153 154 155 /* 156 * Status codes (timex.status) 157 */ 158 #define STA_PLL 0x0001 /* enable PLL updates (rw) */ 159 #define STA_PPSFREQ 0x0002 /* enable PPS freq discipline (rw) */ 160 #define STA_PPSTIME 0x0004 /* enable PPS time discipline (rw) */ 161 #define STA_FLL 0x0008 /* select frequency-lock mode (rw) */ 162 163 #define STA_INS 0x0010 /* insert leap (rw) */ 164 #define STA_DEL 0x0020 /* delete leap (rw) */ 165 #define STA_UNSYNC 0x0040 /* clock unsynchronized (rw) */ 166 #define STA_FREQHOLD 0x0080 /* hold frequency (rw) */ 167 168 #define STA_PPSSIGNAL 0x0100 /* PPS signal present (ro) */ 169 #define STA_PPSJITTER 0x0200 /* PPS signal jitter exceeded (ro) */ 170 #define STA_PPSWANDER 0x0400 /* PPS signal wander exceeded (ro) */ 171 #define STA_PPSERROR 0x0800 /* PPS signal calibration error (ro) */ 172 173 #define STA_CLOCKERR 0x1000 /* clock hardware fault (ro) */ 174 #define STA_NANO 0x2000 /* resolution (0 = us, 1 = ns) (ro) */ 175 #define STA_MODE 0x4000 /* mode (0 = PLL, 1 = FLL) (ro) */ 176 #define STA_CLK 0x8000 /* clock source (0 = A, 1 = B) (ro) */ 177 178 /* read-only bits */ 179 #define STA_RONLY (STA_PPSSIGNAL | STA_PPSJITTER | STA_PPSWANDER | \ 180 STA_PPSERROR | STA_CLOCKERR | STA_NANO | STA_MODE | STA_CLK) 181 182 /* 183 * Clock states (time_state) 184 */ 185 #define TIME_OK 0 /* clock synchronized, no leap second */ 186 #define TIME_INS 1 /* insert leap second */ 187 #define TIME_DEL 2 /* delete leap second */ 188 #define TIME_OOP 3 /* leap second in progress */ 189 #define TIME_WAIT 4 /* leap second has occurred */ 190 #define TIME_ERROR 5 /* clock not synchronized */ 191 #define TIME_BAD TIME_ERROR /* bw compat */ 192 193 194 #endif /* LINUX_TIMEX_H */ 195