1  /* SPDX-License-Identifier: GPL-2.0 */
2  #ifndef _LINUX_TIMEKEEPING_H
3  #define _LINUX_TIMEKEEPING_H
4  
5  #include <linux/errno.h>
6  #include <linux/clocksource_ids.h>
7  
8  /* Included from linux/ktime.h */
9  
10  void timekeeping_init(void);
11  extern int timekeeping_suspended;
12  
13  /* Architecture timer tick functions: */
14  extern void legacy_timer_tick(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   */
ktime_get_real(void)77  static inline ktime_t ktime_get_real(void)
78  {
79  	return ktime_get_with_offset(TK_OFFS_REAL);
80  }
81  
ktime_get_coarse_real(void)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   */
ktime_get_boottime(void)93  static inline ktime_t ktime_get_boottime(void)
94  {
95  	return ktime_get_with_offset(TK_OFFS_BOOT);
96  }
97  
ktime_get_coarse_boottime(void)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   */
ktime_get_clocktai(void)106  static inline ktime_t ktime_get_clocktai(void)
107  {
108  	return ktime_get_with_offset(TK_OFFS_TAI);
109  }
110  
ktime_get_coarse_clocktai(void)111  static inline ktime_t ktime_get_coarse_clocktai(void)
112  {
113  	return ktime_get_coarse_with_offset(TK_OFFS_TAI);
114  }
115  
ktime_get_coarse(void)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  
ktime_get_coarse_ns(void)124  static inline u64 ktime_get_coarse_ns(void)
125  {
126  	return ktime_to_ns(ktime_get_coarse());
127  }
128  
ktime_get_coarse_real_ns(void)129  static inline u64 ktime_get_coarse_real_ns(void)
130  {
131  	return ktime_to_ns(ktime_get_coarse_real());
132  }
133  
ktime_get_coarse_boottime_ns(void)134  static inline u64 ktime_get_coarse_boottime_ns(void)
135  {
136  	return ktime_to_ns(ktime_get_coarse_boottime());
137  }
138  
ktime_get_coarse_clocktai_ns(void)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   */
ktime_mono_to_real(ktime_t mono)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  
ktime_get_ns(void)152  static inline u64 ktime_get_ns(void)
153  {
154  	return ktime_to_ns(ktime_get());
155  }
156  
ktime_get_real_ns(void)157  static inline u64 ktime_get_real_ns(void)
158  {
159  	return ktime_to_ns(ktime_get_real());
160  }
161  
ktime_get_boottime_ns(void)162  static inline u64 ktime_get_boottime_ns(void)
163  {
164  	return ktime_to_ns(ktime_get_boottime());
165  }
166  
ktime_get_clocktai_ns(void)167  static inline u64 ktime_get_clocktai_ns(void)
168  {
169  	return ktime_to_ns(ktime_get_clocktai());
170  }
171  
ktime_get_raw_ns(void)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_tai_fast_ns(void);
181  extern u64 ktime_get_real_fast_ns(void);
182  
183  /*
184   * timespec64/time64_t interfaces utilizing the ktime based ones
185   * for API completeness, these could be implemented more efficiently
186   * if needed.
187   */
ktime_get_boottime_ts64(struct timespec64 * ts)188  static inline void ktime_get_boottime_ts64(struct timespec64 *ts)
189  {
190  	*ts = ktime_to_timespec64(ktime_get_boottime());
191  }
192  
ktime_get_coarse_boottime_ts64(struct timespec64 * ts)193  static inline void ktime_get_coarse_boottime_ts64(struct timespec64 *ts)
194  {
195  	*ts = ktime_to_timespec64(ktime_get_coarse_boottime());
196  }
197  
ktime_get_boottime_seconds(void)198  static inline time64_t ktime_get_boottime_seconds(void)
199  {
200  	return ktime_divns(ktime_get_coarse_boottime(), NSEC_PER_SEC);
201  }
202  
ktime_get_clocktai_ts64(struct timespec64 * ts)203  static inline void ktime_get_clocktai_ts64(struct timespec64 *ts)
204  {
205  	*ts = ktime_to_timespec64(ktime_get_clocktai());
206  }
207  
ktime_get_coarse_clocktai_ts64(struct timespec64 * ts)208  static inline void ktime_get_coarse_clocktai_ts64(struct timespec64 *ts)
209  {
210  	*ts = ktime_to_timespec64(ktime_get_coarse_clocktai());
211  }
212  
ktime_get_clocktai_seconds(void)213  static inline time64_t ktime_get_clocktai_seconds(void)
214  {
215  	return ktime_divns(ktime_get_coarse_clocktai(), NSEC_PER_SEC);
216  }
217  
218  /*
219   * RTC specific
220   */
221  extern bool timekeeping_rtc_skipsuspend(void);
222  extern bool timekeeping_rtc_skipresume(void);
223  
224  extern void timekeeping_inject_sleeptime64(const struct timespec64 *delta);
225  
226  /*
227   * struct ktime_timestanps - Simultaneous mono/boot/real timestamps
228   * @mono:	Monotonic timestamp
229   * @boot:	Boottime timestamp
230   * @real:	Realtime timestamp
231   */
232  struct ktime_timestamps {
233  	u64		mono;
234  	u64		boot;
235  	u64		real;
236  };
237  
238  /**
239   * struct system_time_snapshot - simultaneous raw/real time capture with
240   *				 counter value
241   * @cycles:	Clocksource counter value to produce the system times
242   * @real:	Realtime system time
243   * @raw:	Monotonic raw system time
244   * @clock_was_set_seq:	The sequence number of clock was set events
245   * @cs_was_changed_seq:	The sequence number of clocksource change events
246   */
247  struct system_time_snapshot {
248  	u64			cycles;
249  	ktime_t			real;
250  	ktime_t			raw;
251  	enum clocksource_ids	cs_id;
252  	unsigned int		clock_was_set_seq;
253  	u8			cs_was_changed_seq;
254  };
255  
256  /**
257   * struct system_device_crosststamp - system/device cross-timestamp
258   *				      (synchronized capture)
259   * @device:		Device time
260   * @sys_realtime:	Realtime simultaneous with device time
261   * @sys_monoraw:	Monotonic raw simultaneous with device time
262   */
263  struct system_device_crosststamp {
264  	ktime_t device;
265  	ktime_t sys_realtime;
266  	ktime_t sys_monoraw;
267  };
268  
269  /**
270   * struct system_counterval_t - system counter value with the pointer to the
271   *				corresponding clocksource
272   * @cycles:	System counter value
273   * @cs:		Clocksource corresponding to system counter value. Used by
274   *		timekeeping code to verify comparibility of two cycle values
275   */
276  struct system_counterval_t {
277  	u64			cycles;
278  	struct clocksource	*cs;
279  };
280  
281  /*
282   * Get cross timestamp between system clock and device clock
283   */
284  extern int get_device_system_crosststamp(
285  			int (*get_time_fn)(ktime_t *device_time,
286  				struct system_counterval_t *system_counterval,
287  				void *ctx),
288  			void *ctx,
289  			struct system_time_snapshot *history,
290  			struct system_device_crosststamp *xtstamp);
291  
292  /*
293   * Simultaneously snapshot realtime and monotonic raw clocks
294   */
295  extern void ktime_get_snapshot(struct system_time_snapshot *systime_snapshot);
296  
297  /* NMI safe mono/boot/realtime timestamps */
298  extern void ktime_get_fast_timestamps(struct ktime_timestamps *snap);
299  
300  /*
301   * Persistent clock related interfaces
302   */
303  extern int persistent_clock_is_local;
304  
305  extern void read_persistent_clock64(struct timespec64 *ts);
306  void read_persistent_wall_and_boot_offset(struct timespec64 *wall_clock,
307  					  struct timespec64 *boot_offset);
308  #ifdef CONFIG_GENERIC_CMOS_UPDATE
309  extern int update_persistent_clock64(struct timespec64 now);
310  #endif
311  
312  #endif
313