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