summaryrefslogtreecommitdiff
path: root/include/linux/timekeeping.h
blob: fc12a9ba2c884271a75608211a72173b7ebaa24c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_TIMEKEEPING_H
#define _LINUX_TIMEKEEPING_H

#include <linux/errno.h>
#include <linux/clocksource_ids.h>
#include <linux/ktime.h>

/* Included from linux/ktime.h */

void timekeeping_init(void);
extern int timekeeping_suspended;

/* Architecture timer tick functions: */
extern void legacy_timer_tick(unsigned long ticks);

/*
 * Get and set timeofday
 */
extern int do_settimeofday64(const struct timespec64 *ts);
extern int do_sys_settimeofday64(const struct timespec64 *tv,
				 const struct timezone *tz);

/*
 * ktime_get() family - read the current time in a multitude of ways.
 *
 * The default time reference is CLOCK_MONOTONIC, starting at
 * boot time but not counting the time spent in suspend.
 * For other references, use the functions with "real", "clocktai",
 * "boottime" and "raw" suffixes.
 *
 * To get the time in a different format, use the ones with
 * "ns", "ts64" and "seconds" suffix.
 *
 * See Documentation/core-api/timekeeping.rst for more details.
 */


/*
 * timespec64 based interfaces
 */
extern void ktime_get_raw_ts64(struct timespec64 *ts);
extern void ktime_get_ts64(struct timespec64 *ts);
extern void ktime_get_real_ts64(struct timespec64 *tv);
extern void ktime_get_coarse_ts64(struct timespec64 *ts);
extern void ktime_get_coarse_real_ts64(struct timespec64 *ts);

void getboottime64(struct timespec64 *ts);

/*
 * time64_t base interfaces
 */
extern time64_t ktime_get_seconds(void);
extern time64_t __ktime_get_real_seconds(void);
extern time64_t ktime_get_real_seconds(void);

/*
 * ktime_t based interfaces
 */

enum tk_offsets {
	TK_OFFS_REAL,
	TK_OFFS_BOOT,
	TK_OFFS_TAI,
	TK_OFFS_MAX,
};

extern ktime_t ktime_get(void);
extern ktime_t ktime_get_with_offset(enum tk_offsets offs);
extern ktime_t ktime_get_coarse_with_offset(enum tk_offsets offs);
extern ktime_t ktime_mono_to_any(ktime_t tmono, enum tk_offsets offs);
extern ktime_t ktime_get_raw(void);
extern u32 ktime_get_resolution_ns(void);

/**
 * ktime_get_real - get the real (wall-) time in ktime_t format
 *
 * Returns: real (wall) time in ktime_t format
 */
static inline ktime_t ktime_get_real(void)
{
	return ktime_get_with_offset(TK_OFFS_REAL);
}

static inline ktime_t ktime_get_coarse_real(void)
{
	return ktime_get_coarse_with_offset(TK_OFFS_REAL);
}

/**
 * ktime_get_boottime - Get monotonic time since boot in ktime_t format
 *
 * This is similar to CLOCK_MONTONIC/ktime_get, but also includes the
 * time spent in suspend.
 *
 * Returns: monotonic time since boot in ktime_t format
 */
static inline ktime_t ktime_get_boottime(void)
{
	return ktime_get_with_offset(TK_OFFS_BOOT);
}

static inline ktime_t ktime_get_coarse_boottime(void)
{
	return ktime_get_coarse_with_offset(TK_OFFS_BOOT);
}

/**
 * ktime_get_clocktai - Get the TAI time of day in ktime_t format
 *
 * Returns: the TAI time of day in ktime_t format
 */
static inline ktime_t ktime_get_clocktai(void)
{
	return ktime_get_with_offset(TK_OFFS_TAI);
}

static inline ktime_t ktime_get_coarse_clocktai(void)
{
	return ktime_get_coarse_with_offset(TK_OFFS_TAI);
}

static inline ktime_t ktime_get_coarse(void)
{
	struct timespec64 ts;

	ktime_get_coarse_ts64(&ts);
	return timespec64_to_ktime(ts);
}

static inline u64 ktime_get_coarse_ns(void)
{
	return ktime_to_ns(ktime_get_coarse());
}

static inline u64 ktime_get_coarse_real_ns(void)
{
	return ktime_to_ns(ktime_get_coarse_real());
}

static inline u64 ktime_get_coarse_boottime_ns(void)
{
	return ktime_to_ns(ktime_get_coarse_boottime());
}

static inline u64 ktime_get_coarse_clocktai_ns(void)
{
	return ktime_to_ns(ktime_get_coarse_clocktai());
}

/**
 * ktime_mono_to_real - Convert monotonic time to clock realtime
 * @mono: monotonic time to convert
 *
 * Returns: time converted to realtime clock
 */
static inline ktime_t ktime_mono_to_real(ktime_t mono)
{
	return ktime_mono_to_any(mono, TK_OFFS_REAL);
}

/**
 * ktime_get_ns - Get the current time in nanoseconds
 *
 * Returns: current time converted to nanoseconds
 */
static inline u64 ktime_get_ns(void)
{
	return ktime_to_ns(ktime_get());
}

/**
 * ktime_get_real_ns - Get the current real/wall time in nanoseconds
 *
 * Returns: current real time converted to nanoseconds
 */
static inline u64 ktime_get_real_ns(void)
{
	return ktime_to_ns(ktime_get_real());
}

/**
 * ktime_get_boottime_ns - Get the monotonic time since boot in nanoseconds
 *
 * Returns: current boottime converted to nanoseconds
 */
static inline u64 ktime_get_boottime_ns(void)
{
	return ktime_to_ns(ktime_get_boottime());
}

/**
 * ktime_get_clocktai_ns - Get the current TAI time of day in nanoseconds
 *
 * Returns: current TAI time converted to nanoseconds
 */
static inline u64 ktime_get_clocktai_ns(void)
{
	return ktime_to_ns(ktime_get_clocktai());
}

/**
 * ktime_get_raw_ns - Get the raw monotonic time in nanoseconds
 *
 * Returns: current raw monotonic time converted to nanoseconds
 */
static inline u64 ktime_get_raw_ns(void)
{
	return ktime_to_ns(ktime_get_raw());
}

extern u64 ktime_get_mono_fast_ns(void);
extern u64 ktime_get_raw_fast_ns(void);
extern u64 ktime_get_boot_fast_ns(void);
extern u64 ktime_get_tai_fast_ns(void);
extern u64 ktime_get_real_fast_ns(void);

/*
 * timespec64/time64_t interfaces utilizing the ktime based ones
 * for API completeness, these could be implemented more efficiently
 * if needed.
 */
static inline void ktime_get_boottime_ts64(struct timespec64 *ts)
{
	*ts = ktime_to_timespec64(ktime_get_boottime());
}

static inline void ktime_get_coarse_boottime_ts64(struct timespec64 *ts)
{
	*ts = ktime_to_timespec64(ktime_get_coarse_boottime());
}

static inline time64_t ktime_get_boottime_seconds(void)
{
	return ktime_divns(ktime_get_coarse_boottime(), NSEC_PER_SEC);
}

static inline void ktime_get_clocktai_ts64(struct timespec64 *ts)
{
	*ts = ktime_to_timespec64(ktime_get_clocktai());
}

static inline void ktime_get_coarse_clocktai_ts64(struct timespec64 *ts)
{
	*ts = ktime_to_timespec64(ktime_get_coarse_clocktai());
}

static inline time64_t ktime_get_clocktai_seconds(void)
{
	return ktime_divns(ktime_get_coarse_clocktai(), NSEC_PER_SEC);
}

/*
 * RTC specific
 */
extern bool timekeeping_rtc_skipsuspend(void);
extern bool timekeeping_rtc_skipresume(void);

extern void timekeeping_inject_sleeptime64(const struct timespec64 *delta);

/**
 * struct ktime_timestamps - Simultaneous mono/boot/real timestamps
 * @mono:	Monotonic timestamp
 * @boot:	Boottime timestamp
 * @real:	Realtime timestamp
 */
struct ktime_timestamps {
	u64		mono;
	u64		boot;
	u64		real;
};

/**
 * struct system_time_snapshot - simultaneous raw/real time capture with
 *				 counter value
 * @cycles:	Clocksource counter value to produce the system times
 * @real:	Realtime system time
 * @raw:	Monotonic raw system time
 * @cs_id:	Clocksource ID
 * @clock_was_set_seq:	The sequence number of clock-was-set events
 * @cs_was_changed_seq:	The sequence number of clocksource change events
 */
struct system_time_snapshot {
	u64			cycles;
	ktime_t			real;
	ktime_t			raw;
	enum clocksource_ids	cs_id;
	unsigned int		clock_was_set_seq;
	u8			cs_was_changed_seq;
};

/**
 * struct system_device_crosststamp - system/device cross-timestamp
 *				      (synchronized capture)
 * @device:		Device time
 * @sys_realtime:	Realtime simultaneous with device time
 * @sys_monoraw:	Monotonic raw simultaneous with device time
 */
struct system_device_crosststamp {
	ktime_t device;
	ktime_t sys_realtime;
	ktime_t sys_monoraw;
};

/**
 * struct system_counterval_t - system counter value with the ID of the
 *				corresponding clocksource
 * @cycles:	System counter value
 * @cs_id:	Clocksource ID corresponding to system counter value. Used by
 *		timekeeping code to verify comparability of two cycle values.
 *		The default ID, CSID_GENERIC, does not identify a specific
 *		clocksource.
 * @use_nsecs:	@cycles is in nanoseconds.
 */
struct system_counterval_t {
	u64			cycles;
	enum clocksource_ids	cs_id;
	bool			use_nsecs;
};

extern bool ktime_real_to_base_clock(ktime_t treal,
				     enum clocksource_ids base_id, u64 *cycles);
extern bool timekeeping_clocksource_has_base(enum clocksource_ids id);

/*
 * Get cross timestamp between system clock and device clock
 */
extern int get_device_system_crosststamp(
			int (*get_time_fn)(ktime_t *device_time,
				struct system_counterval_t *system_counterval,
				void *ctx),
			void *ctx,
			struct system_time_snapshot *history,
			struct system_device_crosststamp *xtstamp);

/*
 * Simultaneously snapshot realtime and monotonic raw clocks
 */
extern void ktime_get_snapshot(struct system_time_snapshot *systime_snapshot);

/* NMI safe mono/boot/realtime timestamps */
extern void ktime_get_fast_timestamps(struct ktime_timestamps *snap);

/*
 * Persistent clock related interfaces
 */
extern int persistent_clock_is_local;

extern void read_persistent_clock64(struct timespec64 *ts);
void read_persistent_wall_and_boot_offset(struct timespec64 *wall_clock,
					  struct timespec64 *boot_offset);
#ifdef CONFIG_GENERIC_CMOS_UPDATE
extern int update_persistent_clock64(struct timespec64 now);
#endif

#endif