root/include/linux/timekeeping.h

INCLUDED FROM

DEFINITIONS

1. ktime_get_real
2. ktime_get_coarse_real
3. ktime_get_boottime
4. ktime_get_coarse_boottime
5. ktime_get_clocktai
6. ktime_get_coarse_clocktai
7. ktime_get_coarse
8. ktime_get_coarse_ns
9. ktime_get_coarse_real_ns
10. ktime_get_coarse_boottime_ns
11. ktime_get_coarse_clocktai_ns
12. ktime_mono_to_real
13. ktime_get_ns
14. ktime_get_real_ns
15. ktime_get_boottime_ns
16. ktime_get_clocktai_ns
17. ktime_get_raw_ns
18. ktime_get_boottime_ts64
19. ktime_get_coarse_boottime_ts64
20. ktime_get_boottime_seconds
21. ktime_get_clocktai_ts64
22. ktime_get_coarse_clocktai_ts64
23. ktime_get_clocktai_seconds

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _LINUX_TIMEKEEPING_H
   3 #define _LINUX_TIMEKEEPING_H
   4 
   5 #include <linux/errno.h>
   6 
   7 /* Included from linux/ktime.h */
   8 
   9 void timekeeping_init(void);
  10 extern int timekeeping_suspended;
  11 
  12 /* Architecture timer tick functions: */
  13 extern void update_process_times(int user);
  14 extern void xtime_update(unsigned long ticks);
  15 
  16 /*
  17  * Get and set timeofday
  18  */
  19 extern int do_settimeofday64(const struct timespec64 *ts);
  20 extern int do_sys_settimeofday64(const struct timespec64 *tv,
  21                                  const struct timezone *tz);
  22 
  23 /*
  24  * ktime_get() family: read the current time in a multitude of ways,
  25  *
  26  * The default time reference is CLOCK_MONOTONIC, starting at
  27  * boot time but not counting the time spent in suspend.
  28  * For other references, use the functions with "real", "clocktai",
  29  * "boottime" and "raw" suffixes.
  30  *
  31  * To get the time in a different format, use the ones wit
  32  * "ns", "ts64" and "seconds" suffix.
  33  *
  34  * See Documentation/core-api/timekeeping.rst for more details.
  35  */
  36 
  37 
  38 /*
  39  * timespec64 based interfaces
  40  */
  41 extern void ktime_get_raw_ts64(struct timespec64 *ts);
  42 extern void ktime_get_ts64(struct timespec64 *ts);
  43 extern void ktime_get_real_ts64(struct timespec64 *tv);
  44 extern void ktime_get_coarse_ts64(struct timespec64 *ts);
  45 extern void ktime_get_coarse_real_ts64(struct timespec64 *ts);
  46 
  47 void getboottime64(struct timespec64 *ts);
  48 
  49 /*
  50  * time64_t base interfaces
  51  */
  52 extern time64_t ktime_get_seconds(void);
  53 extern time64_t __ktime_get_real_seconds(void);
  54 extern time64_t ktime_get_real_seconds(void);
  55 
  56 /*
  57  * ktime_t based interfaces
  58  */
  59 
  60 enum tk_offsets {
  61         TK_OFFS_REAL,
  62         TK_OFFS_BOOT,
  63         TK_OFFS_TAI,
  64         TK_OFFS_MAX,
  65 };
  66 
  67 extern ktime_t ktime_get(void);
  68 extern ktime_t ktime_get_with_offset(enum tk_offsets offs);
  69 extern ktime_t ktime_get_coarse_with_offset(enum tk_offsets offs);
  70 extern ktime_t ktime_mono_to_any(ktime_t tmono, enum tk_offsets offs);
  71 extern ktime_t ktime_get_raw(void);
  72 extern u32 ktime_get_resolution_ns(void);
  73 
  74 /**
  75  * ktime_get_real - get the real (wall-) time in ktime_t format
  76  */
  77 static inline ktime_t ktime_get_real(void)
  78 {
  79         return ktime_get_with_offset(TK_OFFS_REAL);
  80 }
  81 
  82 static inline ktime_t ktime_get_coarse_real(void)
  83 {
  84         return ktime_get_coarse_with_offset(TK_OFFS_REAL);
  85 }
  86 
  87 /**
  88  * ktime_get_boottime - Returns monotonic time since boot in ktime_t format
  89  *
  90  * This is similar to CLOCK_MONTONIC/ktime_get, but also includes the
  91  * time spent in suspend.
  92  */
  93 static inline ktime_t ktime_get_boottime(void)
  94 {
  95         return ktime_get_with_offset(TK_OFFS_BOOT);
  96 }
  97 
  98 static inline ktime_t ktime_get_coarse_boottime(void)
  99 {
 100         return ktime_get_coarse_with_offset(TK_OFFS_BOOT);
 101 }
 102 
 103 /**
 104  * ktime_get_clocktai - Returns the TAI time of day in ktime_t format
 105  */
 106 static inline ktime_t ktime_get_clocktai(void)
 107 {
 108         return ktime_get_with_offset(TK_OFFS_TAI);
 109 }
 110 
 111 static inline ktime_t ktime_get_coarse_clocktai(void)
 112 {
 113         return ktime_get_coarse_with_offset(TK_OFFS_TAI);
 114 }
 115 
 116 static inline ktime_t ktime_get_coarse(void)
 117 {
 118         struct timespec64 ts;
 119 
 120         ktime_get_coarse_ts64(&ts);
 121         return timespec64_to_ktime(ts);
 122 }
 123 
 124 static inline u64 ktime_get_coarse_ns(void)
 125 {
 126         return ktime_to_ns(ktime_get_coarse());
 127 }
 128 
 129 static inline u64 ktime_get_coarse_real_ns(void)
 130 {
 131         return ktime_to_ns(ktime_get_coarse_real());
 132 }
 133 
 134 static inline u64 ktime_get_coarse_boottime_ns(void)
 135 {
 136         return ktime_to_ns(ktime_get_coarse_boottime());
 137 }
 138 
 139 static inline u64 ktime_get_coarse_clocktai_ns(void)
 140 {
 141         return ktime_to_ns(ktime_get_coarse_clocktai());
 142 }
 143 
 144 /**
 145  * ktime_mono_to_real - Convert monotonic time to clock realtime
 146  */
 147 static inline ktime_t ktime_mono_to_real(ktime_t mono)
 148 {
 149         return ktime_mono_to_any(mono, TK_OFFS_REAL);
 150 }
 151 
 152 static inline u64 ktime_get_ns(void)
 153 {
 154         return ktime_to_ns(ktime_get());
 155 }
 156 
 157 static inline u64 ktime_get_real_ns(void)
 158 {
 159         return ktime_to_ns(ktime_get_real());
 160 }
 161 
 162 static inline u64 ktime_get_boottime_ns(void)
 163 {
 164         return ktime_to_ns(ktime_get_boottime());
 165 }
 166 
 167 static inline u64 ktime_get_clocktai_ns(void)
 168 {
 169         return ktime_to_ns(ktime_get_clocktai());
 170 }
 171 
 172 static inline u64 ktime_get_raw_ns(void)
 173 {
 174         return ktime_to_ns(ktime_get_raw());
 175 }
 176 
 177 extern u64 ktime_get_mono_fast_ns(void);
 178 extern u64 ktime_get_raw_fast_ns(void);
 179 extern u64 ktime_get_boot_fast_ns(void);
 180 extern u64 ktime_get_real_fast_ns(void);
 181 
 182 /*
 183  * timespec64/time64_t interfaces utilizing the ktime based ones
 184  * for API completeness, these could be implemented more efficiently
 185  * if needed.
 186  */
 187 static inline void ktime_get_boottime_ts64(struct timespec64 *ts)
 188 {
 189         *ts = ktime_to_timespec64(ktime_get_boottime());
 190 }
 191 
 192 static inline void ktime_get_coarse_boottime_ts64(struct timespec64 *ts)
 193 {
 194         *ts = ktime_to_timespec64(ktime_get_coarse_boottime());
 195 }
 196 
 197 static inline time64_t ktime_get_boottime_seconds(void)
 198 {
 199         return ktime_divns(ktime_get_coarse_boottime(), NSEC_PER_SEC);
 200 }
 201 
 202 static inline void ktime_get_clocktai_ts64(struct timespec64 *ts)
 203 {
 204         *ts = ktime_to_timespec64(ktime_get_clocktai());
 205 }
 206 
 207 static inline void ktime_get_coarse_clocktai_ts64(struct timespec64 *ts)
 208 {
 209         *ts = ktime_to_timespec64(ktime_get_coarse_clocktai());
 210 }
 211 
 212 static inline time64_t ktime_get_clocktai_seconds(void)
 213 {
 214         return ktime_divns(ktime_get_coarse_clocktai(), NSEC_PER_SEC);
 215 }
 216 
 217 /*
 218  * RTC specific
 219  */
 220 extern bool timekeeping_rtc_skipsuspend(void);
 221 extern bool timekeeping_rtc_skipresume(void);
 222 
 223 extern void timekeeping_inject_sleeptime64(const struct timespec64 *delta);
 224 
 225 /*
 226  * struct system_time_snapshot - simultaneous raw/real time capture with
 227  *      counter value
 228  * @cycles:     Clocksource counter value to produce the system times
 229  * @real:       Realtime system time
 230  * @raw:        Monotonic raw system time
 231  * @clock_was_set_seq:  The sequence number of clock was set events
 232  * @cs_was_changed_seq: The sequence number of clocksource change events
 233  */
 234 struct system_time_snapshot {
 235         u64             cycles;
 236         ktime_t         real;
 237         ktime_t         raw;
 238         unsigned int    clock_was_set_seq;
 239         u8              cs_was_changed_seq;
 240 };
 241 
 242 /*
 243  * struct system_device_crosststamp - system/device cross-timestamp
 244  *      (syncronized capture)
 245  * @device:             Device time
 246  * @sys_realtime:       Realtime simultaneous with device time
 247  * @sys_monoraw:        Monotonic raw simultaneous with device time
 248  */
 249 struct system_device_crosststamp {
 250         ktime_t device;
 251         ktime_t sys_realtime;
 252         ktime_t sys_monoraw;
 253 };
 254 
 255 /*
 256  * struct system_counterval_t - system counter value with the pointer to the
 257  *      corresponding clocksource
 258  * @cycles:     System counter value
 259  * @cs:         Clocksource corresponding to system counter value. Used by
 260  *      timekeeping code to verify comparibility of two cycle values
 261  */
 262 struct system_counterval_t {
 263         u64                     cycles;
 264         struct clocksource      *cs;
 265 };
 266 
 267 /*
 268  * Get cross timestamp between system clock and device clock
 269  */
 270 extern int get_device_system_crosststamp(
 271                         int (*get_time_fn)(ktime_t *device_time,
 272                                 struct system_counterval_t *system_counterval,
 273                                 void *ctx),
 274                         void *ctx,
 275                         struct system_time_snapshot *history,
 276                         struct system_device_crosststamp *xtstamp);
 277 
 278 /*
 279  * Simultaneously snapshot realtime and monotonic raw clocks
 280  */
 281 extern void ktime_get_snapshot(struct system_time_snapshot *systime_snapshot);
 282 
 283 /*
 284  * Persistent clock related interfaces
 285  */
 286 extern int persistent_clock_is_local;
 287 
 288 extern void read_persistent_clock64(struct timespec64 *ts);
 289 void read_persistent_wall_and_boot_offset(struct timespec64 *wall_clock,
 290                                           struct timespec64 *boot_offset);
 291 extern int update_persistent_clock64(struct timespec64 now);
 292 
 293 #endif