clock.h revision 331722
1/*- 2 * Copyright (c) 1996 The NetBSD Foundation, Inc. 3 * All rights reserved. 4 * 5 * This code is derived from software contributed to The NetBSD Foundation 6 * by Gordon W. Ross 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 18 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 19 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 20 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 21 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 22 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 23 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 24 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 25 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 26 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 27 * POSSIBILITY OF SUCH DAMAGE. 28 * 29 * $NetBSD: clock_subr.h,v 1.7 2000/10/03 13:41:07 tsutsui Exp $ 30 * 31 * 32 * This file is the central clearing-house for calendrical issues. 33 * 34 * In general the kernel does not know about minutes, hours, days, timezones, 35 * daylight savings time, leap-years and such. All that is theoretically a 36 * matter for userland only. 37 * 38 * Parts of kernel code does however care: badly designed filesystems store 39 * timestamps in local time and RTC chips sometimes track time in a local 40 * timezone instead of UTC and so on. 41 * 42 * All that code should go here for service. 43 * 44 * $FreeBSD: stable/11/sys/sys/clock.h 331722 2018-03-29 02:50:57Z eadler $ 45 */ 46 47#ifndef _SYS_CLOCK_H_ 48#define _SYS_CLOCK_H_ 49 50#ifdef _KERNEL /* No user serviceable parts */ 51 52/* 53 * Timezone info from settimeofday(2), usually not used 54 */ 55extern int tz_minuteswest; 56extern int tz_dsttime; 57 58int utc_offset(void); 59 60/* 61 * Structure to hold the values typically reported by time-of-day clocks, 62 * expressed as binary integers (see below for a BCD version). This can be 63 * passed to the conversion functions to be converted to/from a struct timespec. 64 * 65 * On input, the year is interpreted as follows: 66 * 0 - 69 = 2000 - 2069 67 * 70 - 99 = 1970 - 1999 68 * 100 - 199 = 2000 - 2099 (Supports hardware "century bit".) 69 * 200 - 1969 = Invalid. 70 * 1970 - 9999 = Full 4-digit century+year. 71 * 72 * The dow field is ignored (not even validated) on input, but is always 73 * populated with day-of-week on output. 74 * 75 * clock_ct_to_ts() returns EINVAL if any values are out of range. The year 76 * field will always be 4-digit on output. 77 */ 78struct clocktime { 79 int year; /* year (4 digit year) */ 80 int mon; /* month (1 - 12) */ 81 int day; /* day (1 - 31) */ 82 int hour; /* hour (0 - 23) */ 83 int min; /* minute (0 - 59) */ 84 int sec; /* second (0 - 59) */ 85 int dow; /* day of week (0 - 6; 0 = Sunday) */ 86 long nsec; /* nano seconds */ 87}; 88 89int clock_ct_to_ts(const struct clocktime *, struct timespec *); 90void clock_ts_to_ct(const struct timespec *, struct clocktime *); 91 92/* 93 * Structure to hold the values typically reported by time-of-day clocks, 94 * expressed as BCD. This can be passed to the conversion functions to be 95 * converted to/from a struct timespec. 96 * 97 * The clock_bcd_to_ts() function interprets the values in the year through sec 98 * fields as BCD numbers, and returns EINVAL if any BCD values are out of range. 99 * After conversion to binary, the values are passed to clock_ct_to_ts() and 100 * undergo further validation as described above. Year may be 2 or 4-digit BCD, 101 * interpreted as described above. The nsec field is binary. If the ampm arg 102 * is true, the incoming hour and ispm values are interpreted as 12-hour am/pm 103 * representation of the hour, otherwise hour is interpreted as 24-hour and ispm 104 * is ignored. 105 * 106 * The clock_ts_to_bcd() function converts the timespec to BCD values stored 107 * into year through sec. The value in year will be 4-digit BCD (e.g., 108 * 0x2017). The mon through sec values will be 2-digit BCD. The nsec field will 109 * be binary, and the range of dow makes its binary and BCD values identical. 110 * If the ampm arg is true, the hour and ispm fields are set to the 12-hour 111 * time plus a pm flag, otherwise the hour is set to 24-hour time and ispm is 112 * set to false. 113 */ 114struct bcd_clocktime { 115 uint16_t year; /* year (2 or 4 digit year) */ 116 uint8_t mon; /* month (1 - 12) */ 117 uint8_t day; /* day (1 - 31) */ 118 uint8_t hour; /* hour (0 - 23 or 1 - 12) */ 119 uint8_t min; /* minute (0 - 59) */ 120 uint8_t sec; /* second (0 - 59) */ 121 uint8_t dow; /* day of week (0 - 6; 0 = Sunday) */ 122 long nsec; /* nanoseconds */ 123 bool ispm; /* true if hour represents pm time */ 124}; 125 126int clock_bcd_to_ts(const struct bcd_clocktime *, struct timespec *, bool ampm); 127void clock_ts_to_bcd(const struct timespec *, struct bcd_clocktime *, bool ampm); 128 129/* 130 * Time-of-day clock functions and flags. These functions might sleep. 131 * 132 * clock_register and clock_unregister() do what they say. Upon return from 133 * unregister, the clock's methods are not running and will not be called again. 134 * 135 * clock_schedule() requests that a registered clock's clock_settime() calls 136 * happen at the given offset into the second. The default is 0, meaning no 137 * specific scheduling. To schedule the call as soon after top-of-second as 138 * possible, specify 1. Each clock has its own schedule, but taskqueue_thread 139 * is shared by many tasks; the timing of the call is not guaranteed. 140 * 141 * Flags: 142 * 143 * CLOCKF_SETTIME_NO_TS 144 * Do not pass a timespec to clock_settime(), the driver obtains its own time 145 * and applies its own adjustments (this flag implies CLOCKF_SETTIME_NO_ADJ). 146 * 147 * CLOCKF_SETTIME_NO_ADJ 148 * Do not apply utc offset and resolution/accuracy adjustments to the value 149 * passed to clock_settime(), the driver applies them itself. 150 * 151 * CLOCKF_GETTIME_NO_ADJ 152 * Do not apply utc offset and resolution/accuracy adjustments to the value 153 * returned from clock_gettime(), the driver has already applied them. 154 */ 155 156#define CLOCKF_SETTIME_NO_TS 0x00000001 157#define CLOCKF_SETTIME_NO_ADJ 0x00000002 158#define CLOCKF_GETTIME_NO_ADJ 0x00000004 159 160void clock_register(device_t _clockdev, long _resolution_us); 161void clock_register_flags(device_t _clockdev, long _resolution_us, int _flags); 162void clock_schedule(device_t clockdev, u_int _offsetns); 163void clock_unregister(device_t _clockdev); 164 165/* 166 * BCD to decimal and decimal to BCD. 167 */ 168#define FROMBCD(x) bcd2bin(x) 169#define TOBCD(x) bin2bcd(x) 170 171/* Some handy constants. */ 172#define SECDAY (24 * 60 * 60) 173#define SECYR (SECDAY * 365) 174 175/* Traditional POSIX base year */ 176#define POSIX_BASE_YEAR 1970 177 178void timespec2fattime(const struct timespec *tsp, int utc, u_int16_t *ddp, 179 u_int16_t *dtp, u_int8_t *dhp); 180void fattime2timespec(unsigned dd, unsigned dt, unsigned dh, int utc, 181 struct timespec *tsp); 182 183/* 184 * Print a [bcd_]clocktime or timespec, optionally with fractional seconds. The 185 * nsdig argument can range from 0-9, and specifies how many decimal digits to 186 * display for fractional seconds. 187 */ 188void clock_print_bcd(const struct bcd_clocktime *bct, int nsdig); 189void clock_print_ct(const struct clocktime *ct, int nsdig); 190void clock_print_ts(const struct timespec *ts, int nsdig); 191 192/* 193 * Debugging helpers for RTC clock drivers. Print a [bcd_]clocktime or 194 * timespec, only if rtc clock debugging has been enabled. The rw argument is 195 * one of CLOCK_DBG_READ or CLOCK_DBG_WRITE. 196 */ 197#define CLOCK_DBG_READ 0x01 198#define CLOCK_DBG_WRITE 0x02 199void clock_dbgprint_bcd(device_t dev, int rw, const struct bcd_clocktime *bct); 200void clock_dbgprint_ct(device_t dev, int rw, const struct clocktime *ct); 201void clock_dbgprint_err(device_t dev, int rw, int err); 202void clock_dbgprint_ts(device_t dev, int rw, const struct timespec *ts); 203 204#endif /* _KERNEL */ 205 206#endif /* !_SYS_CLOCK_H_ */ 207