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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#include <linux/ktime.h>
8
9/* Included from linux/ktime.h */
10
11void timekeeping_init(void);
12extern int timekeeping_suspended;
13
14/* Architecture timer tick functions: */
15extern void legacy_timer_tick(unsigned long ticks);
16
17/*
18 * Get and set timeofday
19 */
20extern int do_settimeofday64(const struct timespec64 *ts);
21extern int do_sys_settimeofday64(const struct timespec64 *tv,
22 const struct timezone *tz);
23
24/*
25 * ktime_get() family: read the current time in a multitude of ways,
26 *
27 * The default time reference is CLOCK_MONOTONIC, starting at
28 * boot time but not counting the time spent in suspend.
29 * For other references, use the functions with "real", "clocktai",
30 * "boottime" and "raw" suffixes.
31 *
32 * To get the time in a different format, use the ones wit
33 * "ns", "ts64" and "seconds" suffix.
34 *
35 * See Documentation/core-api/timekeeping.rst for more details.
36 */
37
38
39/*
40 * timespec64 based interfaces
41 */
42extern void ktime_get_raw_ts64(struct timespec64 *ts);
43extern void ktime_get_ts64(struct timespec64 *ts);
44extern void ktime_get_real_ts64(struct timespec64 *tv);
45extern void ktime_get_coarse_ts64(struct timespec64 *ts);
46extern void ktime_get_coarse_real_ts64(struct timespec64 *ts);
47
48void getboottime64(struct timespec64 *ts);
49
50/*
51 * time64_t base interfaces
52 */
53extern time64_t ktime_get_seconds(void);
54extern time64_t __ktime_get_real_seconds(void);
55extern time64_t ktime_get_real_seconds(void);
56
57/*
58 * ktime_t based interfaces
59 */
60
61enum tk_offsets {
62 TK_OFFS_REAL,
63 TK_OFFS_BOOT,
64 TK_OFFS_TAI,
65 TK_OFFS_MAX,
66};
67
68extern ktime_t ktime_get(void);
69extern ktime_t ktime_get_with_offset(enum tk_offsets offs);
70extern ktime_t ktime_get_coarse_with_offset(enum tk_offsets offs);
71extern ktime_t ktime_mono_to_any(ktime_t tmono, enum tk_offsets offs);
72extern ktime_t ktime_get_raw(void);
73extern u32 ktime_get_resolution_ns(void);
74
75/**
76 * ktime_get_real - get the real (wall-) time in ktime_t format
77 */
78static inline ktime_t ktime_get_real(void)
79{
80 return ktime_get_with_offset(TK_OFFS_REAL);
81}
82
83static inline ktime_t ktime_get_coarse_real(void)
84{
85 return ktime_get_coarse_with_offset(TK_OFFS_REAL);
86}
87
88/**
89 * ktime_get_boottime - Returns monotonic time since boot in ktime_t format
90 *
91 * This is similar to CLOCK_MONTONIC/ktime_get, but also includes the
92 * time spent in suspend.
93 */
94static inline ktime_t ktime_get_boottime(void)
95{
96 return ktime_get_with_offset(TK_OFFS_BOOT);
97}
98
99static inline ktime_t ktime_get_coarse_boottime(void)
100{
101 return ktime_get_coarse_with_offset(TK_OFFS_BOOT);
102}
103
104/**
105 * ktime_get_clocktai - Returns the TAI time of day in ktime_t format
106 */
107static inline ktime_t ktime_get_clocktai(void)
108{
109 return ktime_get_with_offset(TK_OFFS_TAI);
110}
111
112static inline ktime_t ktime_get_coarse_clocktai(void)
113{
114 return ktime_get_coarse_with_offset(TK_OFFS_TAI);
115}
116
117static inline ktime_t ktime_get_coarse(void)
118{
119 struct timespec64 ts;
120
121 ktime_get_coarse_ts64(&ts);
122 return timespec64_to_ktime(ts);
123}
124
125static inline u64 ktime_get_coarse_ns(void)
126{
127 return ktime_to_ns(ktime_get_coarse());
128}
129
130static inline u64 ktime_get_coarse_real_ns(void)
131{
132 return ktime_to_ns(ktime_get_coarse_real());
133}
134
135static inline u64 ktime_get_coarse_boottime_ns(void)
136{
137 return ktime_to_ns(ktime_get_coarse_boottime());
138}
139
140static inline u64 ktime_get_coarse_clocktai_ns(void)
141{
142 return ktime_to_ns(ktime_get_coarse_clocktai());
143}
144
145/**
146 * ktime_mono_to_real - Convert monotonic time to clock realtime
147 */
148static inline ktime_t ktime_mono_to_real(ktime_t mono)
149{
150 return ktime_mono_to_any(mono, TK_OFFS_REAL);
151}
152
153static inline u64 ktime_get_ns(void)
154{
155 return ktime_to_ns(ktime_get());
156}
157
158static inline u64 ktime_get_real_ns(void)
159{
160 return ktime_to_ns(ktime_get_real());
161}
162
163static inline u64 ktime_get_boottime_ns(void)
164{
165 return ktime_to_ns(ktime_get_boottime());
166}
167
168static inline u64 ktime_get_clocktai_ns(void)
169{
170 return ktime_to_ns(ktime_get_clocktai());
171}
172
173static inline u64 ktime_get_raw_ns(void)
174{
175 return ktime_to_ns(ktime_get_raw());
176}
177
178extern u64 ktime_get_mono_fast_ns(void);
179extern u64 ktime_get_raw_fast_ns(void);
180extern u64 ktime_get_boot_fast_ns(void);
181extern u64 ktime_get_tai_fast_ns(void);
182extern u64 ktime_get_real_fast_ns(void);
183
184/*
185 * timespec64/time64_t interfaces utilizing the ktime based ones
186 * for API completeness, these could be implemented more efficiently
187 * if needed.
188 */
189static inline void ktime_get_boottime_ts64(struct timespec64 *ts)
190{
191 *ts = ktime_to_timespec64(ktime_get_boottime());
192}
193
194static inline void ktime_get_coarse_boottime_ts64(struct timespec64 *ts)
195{
196 *ts = ktime_to_timespec64(ktime_get_coarse_boottime());
197}
198
199static inline time64_t ktime_get_boottime_seconds(void)
200{
201 return ktime_divns(ktime_get_coarse_boottime(), NSEC_PER_SEC);
202}
203
204static inline void ktime_get_clocktai_ts64(struct timespec64 *ts)
205{
206 *ts = ktime_to_timespec64(ktime_get_clocktai());
207}
208
209static inline void ktime_get_coarse_clocktai_ts64(struct timespec64 *ts)
210{
211 *ts = ktime_to_timespec64(ktime_get_coarse_clocktai());
212}
213
214static inline time64_t ktime_get_clocktai_seconds(void)
215{
216 return ktime_divns(ktime_get_coarse_clocktai(), NSEC_PER_SEC);
217}
218
219/*
220 * RTC specific
221 */
222extern bool timekeeping_rtc_skipsuspend(void);
223extern bool timekeeping_rtc_skipresume(void);
224
225extern void timekeeping_inject_sleeptime64(const struct timespec64 *delta);
226
227/*
228 * struct ktime_timestanps - Simultaneous mono/boot/real timestamps
229 * @mono: Monotonic timestamp
230 * @boot: Boottime timestamp
231 * @real: Realtime timestamp
232 */
233struct ktime_timestamps {
234 u64 mono;
235 u64 boot;
236 u64 real;
237};
238
239/**
240 * struct system_time_snapshot - simultaneous raw/real time capture with
241 * counter value
242 * @cycles: Clocksource counter value to produce the system times
243 * @real: Realtime system time
244 * @raw: Monotonic raw system time
245 * @clock_was_set_seq: The sequence number of clock was set events
246 * @cs_was_changed_seq: The sequence number of clocksource change events
247 */
248struct system_time_snapshot {
249 u64 cycles;
250 ktime_t real;
251 ktime_t raw;
252 enum clocksource_ids cs_id;
253 unsigned int clock_was_set_seq;
254 u8 cs_was_changed_seq;
255};
256
257/**
258 * struct system_device_crosststamp - system/device cross-timestamp
259 * (synchronized capture)
260 * @device: Device time
261 * @sys_realtime: Realtime simultaneous with device time
262 * @sys_monoraw: Monotonic raw simultaneous with device time
263 */
264struct system_device_crosststamp {
265 ktime_t device;
266 ktime_t sys_realtime;
267 ktime_t sys_monoraw;
268};
269
270/**
271 * struct system_counterval_t - system counter value with the pointer to the
272 * corresponding clocksource
273 * @cycles: System counter value
274 * @cs: Clocksource corresponding to system counter value. Used by
275 * timekeeping code to verify comparibility of two cycle values
276 */
277struct system_counterval_t {
278 u64 cycles;
279 struct clocksource *cs;
280};
281
282/*
283 * Get cross timestamp between system clock and device clock
284 */
285extern int get_device_system_crosststamp(
286 int (*get_time_fn)(ktime_t *device_time,
287 struct system_counterval_t *system_counterval,
288 void *ctx),
289 void *ctx,
290 struct system_time_snapshot *history,
291 struct system_device_crosststamp *xtstamp);
292
293/*
294 * Simultaneously snapshot realtime and monotonic raw clocks
295 */
296extern void ktime_get_snapshot(struct system_time_snapshot *systime_snapshot);
297
298/* NMI safe mono/boot/realtime timestamps */
299extern void ktime_get_fast_timestamps(struct ktime_timestamps *snap);
300
301/*
302 * Persistent clock related interfaces
303 */
304extern int persistent_clock_is_local;
305
306extern void read_persistent_clock64(struct timespec64 *ts);
307void read_persistent_wall_and_boot_offset(struct timespec64 *wall_clock,
308 struct timespec64 *boot_offset);
309#ifdef CONFIG_GENERIC_CMOS_UPDATE
310extern int update_persistent_clock64(struct timespec64 now);
311#endif
312
313#endif