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