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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 with
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
48/* Multigrain timestamp interfaces */
49extern void ktime_get_coarse_real_ts64_mg(struct timespec64 *ts);
50extern void ktime_get_real_ts64_mg(struct timespec64 *ts);
51extern unsigned long timekeeping_get_mg_floor_swaps(void);
52
53void getboottime64(struct timespec64 *ts);
54
55/*
56 * time64_t base interfaces
57 */
58extern time64_t ktime_get_seconds(void);
59extern time64_t __ktime_get_real_seconds(void);
60extern time64_t ktime_get_real_seconds(void);
61
62/*
63 * ktime_t based interfaces
64 */
65
66enum tk_offsets {
67 TK_OFFS_REAL,
68 TK_OFFS_BOOT,
69 TK_OFFS_TAI,
70 TK_OFFS_MAX,
71};
72
73extern ktime_t ktime_get(void);
74extern ktime_t ktime_get_with_offset(enum tk_offsets offs);
75extern ktime_t ktime_get_coarse_with_offset(enum tk_offsets offs);
76extern ktime_t ktime_mono_to_any(ktime_t tmono, enum tk_offsets offs);
77extern ktime_t ktime_get_raw(void);
78extern u32 ktime_get_resolution_ns(void);
79
80/**
81 * ktime_get_real - get the real (wall-) time in ktime_t format
82 *
83 * Returns: real (wall) time in ktime_t format
84 */
85static inline ktime_t ktime_get_real(void)
86{
87 return ktime_get_with_offset(TK_OFFS_REAL);
88}
89
90static inline ktime_t ktime_get_coarse_real(void)
91{
92 return ktime_get_coarse_with_offset(TK_OFFS_REAL);
93}
94
95/**
96 * ktime_get_boottime - Get monotonic time since boot in ktime_t format
97 *
98 * This is similar to CLOCK_MONTONIC/ktime_get, but also includes the
99 * time spent in suspend.
100 *
101 * Returns: monotonic time since boot in ktime_t format
102 */
103static inline ktime_t ktime_get_boottime(void)
104{
105 return ktime_get_with_offset(TK_OFFS_BOOT);
106}
107
108static inline ktime_t ktime_get_coarse_boottime(void)
109{
110 return ktime_get_coarse_with_offset(TK_OFFS_BOOT);
111}
112
113/**
114 * ktime_get_clocktai - Get the TAI time of day in ktime_t format
115 *
116 * Returns: the TAI time of day in ktime_t format
117 */
118static inline ktime_t ktime_get_clocktai(void)
119{
120 return ktime_get_with_offset(TK_OFFS_TAI);
121}
122
123static inline ktime_t ktime_get_coarse_clocktai(void)
124{
125 return ktime_get_coarse_with_offset(TK_OFFS_TAI);
126}
127
128static inline ktime_t ktime_get_coarse(void)
129{
130 struct timespec64 ts;
131
132 ktime_get_coarse_ts64(&ts);
133 return timespec64_to_ktime(ts);
134}
135
136static inline u64 ktime_get_coarse_ns(void)
137{
138 return ktime_to_ns(ktime_get_coarse());
139}
140
141static inline u64 ktime_get_coarse_real_ns(void)
142{
143 return ktime_to_ns(ktime_get_coarse_real());
144}
145
146static inline u64 ktime_get_coarse_boottime_ns(void)
147{
148 return ktime_to_ns(ktime_get_coarse_boottime());
149}
150
151static inline u64 ktime_get_coarse_clocktai_ns(void)
152{
153 return ktime_to_ns(ktime_get_coarse_clocktai());
154}
155
156/**
157 * ktime_mono_to_real - Convert monotonic time to clock realtime
158 * @mono: monotonic time to convert
159 *
160 * Returns: time converted to realtime clock
161 */
162static inline ktime_t ktime_mono_to_real(ktime_t mono)
163{
164 return ktime_mono_to_any(mono, TK_OFFS_REAL);
165}
166
167/**
168 * ktime_get_ns - Get the current time in nanoseconds
169 *
170 * Returns: current time converted to nanoseconds
171 */
172static inline u64 ktime_get_ns(void)
173{
174 return ktime_to_ns(ktime_get());
175}
176
177/**
178 * ktime_get_real_ns - Get the current real/wall time in nanoseconds
179 *
180 * Returns: current real time converted to nanoseconds
181 */
182static inline u64 ktime_get_real_ns(void)
183{
184 return ktime_to_ns(ktime_get_real());
185}
186
187/**
188 * ktime_get_boottime_ns - Get the monotonic time since boot in nanoseconds
189 *
190 * Returns: current boottime converted to nanoseconds
191 */
192static inline u64 ktime_get_boottime_ns(void)
193{
194 return ktime_to_ns(ktime_get_boottime());
195}
196
197/**
198 * ktime_get_clocktai_ns - Get the current TAI time of day in nanoseconds
199 *
200 * Returns: current TAI time converted to nanoseconds
201 */
202static inline u64 ktime_get_clocktai_ns(void)
203{
204 return ktime_to_ns(ktime_get_clocktai());
205}
206
207/**
208 * ktime_get_raw_ns - Get the raw monotonic time in nanoseconds
209 *
210 * Returns: current raw monotonic time converted to nanoseconds
211 */
212static inline u64 ktime_get_raw_ns(void)
213{
214 return ktime_to_ns(ktime_get_raw());
215}
216
217extern u64 ktime_get_mono_fast_ns(void);
218extern u64 ktime_get_raw_fast_ns(void);
219extern u64 ktime_get_boot_fast_ns(void);
220extern u64 ktime_get_tai_fast_ns(void);
221extern u64 ktime_get_real_fast_ns(void);
222
223/*
224 * timespec64/time64_t interfaces utilizing the ktime based ones
225 * for API completeness, these could be implemented more efficiently
226 * if needed.
227 */
228static inline void ktime_get_boottime_ts64(struct timespec64 *ts)
229{
230 *ts = ktime_to_timespec64(ktime_get_boottime());
231}
232
233static inline void ktime_get_coarse_boottime_ts64(struct timespec64 *ts)
234{
235 *ts = ktime_to_timespec64(ktime_get_coarse_boottime());
236}
237
238static inline time64_t ktime_get_boottime_seconds(void)
239{
240 return ktime_divns(ktime_get_coarse_boottime(), NSEC_PER_SEC);
241}
242
243static inline void ktime_get_clocktai_ts64(struct timespec64 *ts)
244{
245 *ts = ktime_to_timespec64(ktime_get_clocktai());
246}
247
248static inline void ktime_get_coarse_clocktai_ts64(struct timespec64 *ts)
249{
250 *ts = ktime_to_timespec64(ktime_get_coarse_clocktai());
251}
252
253static inline time64_t ktime_get_clocktai_seconds(void)
254{
255 return ktime_divns(ktime_get_coarse_clocktai(), NSEC_PER_SEC);
256}
257
258/*
259 * RTC specific
260 */
261extern bool timekeeping_rtc_skipsuspend(void);
262extern bool timekeeping_rtc_skipresume(void);
263
264extern void timekeeping_inject_sleeptime64(const struct timespec64 *delta);
265
266/**
267 * struct ktime_timestamps - Simultaneous mono/boot/real timestamps
268 * @mono: Monotonic timestamp
269 * @boot: Boottime timestamp
270 * @real: Realtime timestamp
271 */
272struct ktime_timestamps {
273 u64 mono;
274 u64 boot;
275 u64 real;
276};
277
278/**
279 * struct system_time_snapshot - simultaneous raw/real time capture with
280 * counter value
281 * @cycles: Clocksource counter value to produce the system times
282 * @real: Realtime system time
283 * @boot: Boot time
284 * @raw: Monotonic raw system time
285 * @cs_id: Clocksource ID
286 * @clock_was_set_seq: The sequence number of clock-was-set events
287 * @cs_was_changed_seq: The sequence number of clocksource change events
288 */
289struct system_time_snapshot {
290 u64 cycles;
291 ktime_t real;
292 ktime_t boot;
293 ktime_t raw;
294 enum clocksource_ids cs_id;
295 unsigned int clock_was_set_seq;
296 u8 cs_was_changed_seq;
297};
298
299/**
300 * struct system_device_crosststamp - system/device cross-timestamp
301 * (synchronized capture)
302 * @device: Device time
303 * @sys_realtime: Realtime simultaneous with device time
304 * @sys_monoraw: Monotonic raw simultaneous with device time
305 */
306struct system_device_crosststamp {
307 ktime_t device;
308 ktime_t sys_realtime;
309 ktime_t sys_monoraw;
310};
311
312/**
313 * struct system_counterval_t - system counter value with the ID of the
314 * corresponding clocksource
315 * @cycles: System counter value
316 * @cs_id: Clocksource ID corresponding to system counter value. Used by
317 * timekeeping code to verify comparability of two cycle values.
318 * The default ID, CSID_GENERIC, does not identify a specific
319 * clocksource.
320 * @use_nsecs: @cycles is in nanoseconds.
321 */
322struct system_counterval_t {
323 u64 cycles;
324 enum clocksource_ids cs_id;
325 bool use_nsecs;
326};
327
328extern bool ktime_real_to_base_clock(ktime_t treal,
329 enum clocksource_ids base_id, u64 *cycles);
330extern bool timekeeping_clocksource_has_base(enum clocksource_ids id);
331
332/*
333 * Get cross timestamp between system clock and device clock
334 */
335extern int get_device_system_crosststamp(
336 int (*get_time_fn)(ktime_t *device_time,
337 struct system_counterval_t *system_counterval,
338 void *ctx),
339 void *ctx,
340 struct system_time_snapshot *history,
341 struct system_device_crosststamp *xtstamp);
342
343/*
344 * Simultaneously snapshot realtime and monotonic raw clocks
345 */
346extern void ktime_get_snapshot(struct system_time_snapshot *systime_snapshot);
347
348/* NMI safe mono/boot/realtime timestamps */
349extern void ktime_get_fast_timestamps(struct ktime_timestamps *snap);
350
351/*
352 * Persistent clock related interfaces
353 */
354extern int persistent_clock_is_local;
355
356extern void read_persistent_clock64(struct timespec64 *ts);
357void read_persistent_wall_and_boot_offset(struct timespec64 *wall_clock,
358 struct timespec64 *boot_offset);
359#ifdef CONFIG_GENERIC_CMOS_UPDATE
360extern int update_persistent_clock64(struct timespec64 now);
361#endif
362
363#endif