xref: /linux-6.15/include/linux/timekeeping.h (revision 6da2ec56)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_TIMEKEEPING_H
3 #define _LINUX_TIMEKEEPING_H
4 
5 #include <linux/errno.h>
6 
7 /* Included from linux/ktime.h */
8 
9 void timekeeping_init(void);
10 extern int timekeeping_suspended;
11 
12 /* Architecture timer tick functions: */
13 extern void update_process_times(int user);
14 extern void xtime_update(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  * timespec64 based interfaces
25  */
26 extern void ktime_get_raw_ts64(struct timespec64 *ts);
27 extern void ktime_get_ts64(struct timespec64 *ts);
28 extern void ktime_get_real_ts64(struct timespec64 *tv);
29 extern void ktime_get_coarse_ts64(struct timespec64 *ts);
30 extern void ktime_get_coarse_real_ts64(struct timespec64 *ts);
31 
32 void getboottime64(struct timespec64 *ts);
33 
34 /*
35  * time64_t base interfaces
36  */
37 extern time64_t ktime_get_seconds(void);
38 extern time64_t __ktime_get_real_seconds(void);
39 extern time64_t ktime_get_real_seconds(void);
40 
41 /*
42  * ktime_t based interfaces
43  */
44 
45 enum tk_offsets {
46 	TK_OFFS_REAL,
47 	TK_OFFS_BOOT,
48 	TK_OFFS_TAI,
49 	TK_OFFS_MAX,
50 };
51 
52 extern ktime_t ktime_get(void);
53 extern ktime_t ktime_get_with_offset(enum tk_offsets offs);
54 extern ktime_t ktime_get_coarse_with_offset(enum tk_offsets offs);
55 extern ktime_t ktime_mono_to_any(ktime_t tmono, enum tk_offsets offs);
56 extern ktime_t ktime_get_raw(void);
57 extern u32 ktime_get_resolution_ns(void);
58 
59 /**
60  * ktime_get_real - get the real (wall-) time in ktime_t format
61  */
62 static inline ktime_t ktime_get_real(void)
63 {
64 	return ktime_get_with_offset(TK_OFFS_REAL);
65 }
66 
67 static inline ktime_t ktime_get_coarse_real(void)
68 {
69 	return ktime_get_coarse_with_offset(TK_OFFS_REAL);
70 }
71 
72 /**
73  * ktime_get_boottime - Returns monotonic time since boot in ktime_t format
74  *
75  * This is similar to CLOCK_MONTONIC/ktime_get, but also includes the
76  * time spent in suspend.
77  */
78 static inline ktime_t ktime_get_boottime(void)
79 {
80 	return ktime_get_with_offset(TK_OFFS_BOOT);
81 }
82 
83 static inline ktime_t ktime_get_coarse_boottime(void)
84 {
85 	return ktime_get_coarse_with_offset(TK_OFFS_BOOT);
86 }
87 
88 /**
89  * ktime_get_clocktai - Returns the TAI time of day in ktime_t format
90  */
91 static inline ktime_t ktime_get_clocktai(void)
92 {
93 	return ktime_get_with_offset(TK_OFFS_TAI);
94 }
95 
96 static inline ktime_t ktime_get_coarse_clocktai(void)
97 {
98 	return ktime_get_coarse_with_offset(TK_OFFS_TAI);
99 }
100 
101 /**
102  * ktime_mono_to_real - Convert monotonic time to clock realtime
103  */
104 static inline ktime_t ktime_mono_to_real(ktime_t mono)
105 {
106 	return ktime_mono_to_any(mono, TK_OFFS_REAL);
107 }
108 
109 static inline u64 ktime_get_ns(void)
110 {
111 	return ktime_to_ns(ktime_get());
112 }
113 
114 static inline u64 ktime_get_real_ns(void)
115 {
116 	return ktime_to_ns(ktime_get_real());
117 }
118 
119 static inline u64 ktime_get_boot_ns(void)
120 {
121 	return ktime_to_ns(ktime_get_boottime());
122 }
123 
124 static inline u64 ktime_get_tai_ns(void)
125 {
126 	return ktime_to_ns(ktime_get_clocktai());
127 }
128 
129 static inline u64 ktime_get_raw_ns(void)
130 {
131 	return ktime_to_ns(ktime_get_raw());
132 }
133 
134 extern u64 ktime_get_mono_fast_ns(void);
135 extern u64 ktime_get_raw_fast_ns(void);
136 extern u64 ktime_get_boot_fast_ns(void);
137 extern u64 ktime_get_real_fast_ns(void);
138 
139 /*
140  * timespec64/time64_t interfaces utilizing the ktime based ones
141  * for API completeness, these could be implemented more efficiently
142  * if needed.
143  */
144 static inline void ktime_get_boottime_ts64(struct timespec64 *ts)
145 {
146 	*ts = ktime_to_timespec64(ktime_get_boottime());
147 }
148 
149 static inline void ktime_get_coarse_boottime_ts64(struct timespec64 *ts)
150 {
151 	*ts = ktime_to_timespec64(ktime_get_coarse_boottime());
152 }
153 
154 static inline time64_t ktime_get_boottime_seconds(void)
155 {
156 	return ktime_divns(ktime_get_coarse_boottime(), NSEC_PER_SEC);
157 }
158 
159 static inline void ktime_get_clocktai_ts64(struct timespec64 *ts)
160 {
161 	*ts = ktime_to_timespec64(ktime_get_clocktai());
162 }
163 
164 static inline void ktime_get_coarse_clocktai_ts64(struct timespec64 *ts)
165 {
166 	*ts = ktime_to_timespec64(ktime_get_coarse_clocktai());
167 }
168 
169 static inline time64_t ktime_get_clocktai_seconds(void)
170 {
171 	return ktime_divns(ktime_get_coarse_clocktai(), NSEC_PER_SEC);
172 }
173 
174 /*
175  * RTC specific
176  */
177 extern bool timekeeping_rtc_skipsuspend(void);
178 extern bool timekeeping_rtc_skipresume(void);
179 
180 extern void timekeeping_inject_sleeptime64(struct timespec64 *delta);
181 
182 /*
183  * struct system_time_snapshot - simultaneous raw/real time capture with
184  *	counter value
185  * @cycles:	Clocksource counter value to produce the system times
186  * @real:	Realtime system time
187  * @raw:	Monotonic raw system time
188  * @clock_was_set_seq:	The sequence number of clock was set events
189  * @cs_was_changed_seq:	The sequence number of clocksource change events
190  */
191 struct system_time_snapshot {
192 	u64		cycles;
193 	ktime_t		real;
194 	ktime_t		raw;
195 	unsigned int	clock_was_set_seq;
196 	u8		cs_was_changed_seq;
197 };
198 
199 /*
200  * struct system_device_crosststamp - system/device cross-timestamp
201  *	(syncronized capture)
202  * @device:		Device time
203  * @sys_realtime:	Realtime simultaneous with device time
204  * @sys_monoraw:	Monotonic raw simultaneous with device time
205  */
206 struct system_device_crosststamp {
207 	ktime_t device;
208 	ktime_t sys_realtime;
209 	ktime_t sys_monoraw;
210 };
211 
212 /*
213  * struct system_counterval_t - system counter value with the pointer to the
214  *	corresponding clocksource
215  * @cycles:	System counter value
216  * @cs:		Clocksource corresponding to system counter value. Used by
217  *	timekeeping code to verify comparibility of two cycle values
218  */
219 struct system_counterval_t {
220 	u64			cycles;
221 	struct clocksource	*cs;
222 };
223 
224 /*
225  * Get cross timestamp between system clock and device clock
226  */
227 extern int get_device_system_crosststamp(
228 			int (*get_time_fn)(ktime_t *device_time,
229 				struct system_counterval_t *system_counterval,
230 				void *ctx),
231 			void *ctx,
232 			struct system_time_snapshot *history,
233 			struct system_device_crosststamp *xtstamp);
234 
235 /*
236  * Simultaneously snapshot realtime and monotonic raw clocks
237  */
238 extern void ktime_get_snapshot(struct system_time_snapshot *systime_snapshot);
239 
240 /*
241  * Persistent clock related interfaces
242  */
243 extern int persistent_clock_is_local;
244 
245 extern void read_persistent_clock64(struct timespec64 *ts);
246 extern void read_boot_clock64(struct timespec64 *ts);
247 extern int update_persistent_clock64(struct timespec64 now);
248 
249 /*
250  * deprecated aliases, don't use in new code
251  */
252 #define getnstimeofday64(ts)		ktime_get_real_ts64(ts)
253 #define get_monotonic_boottime64(ts)	ktime_get_boottime_ts64(ts)
254 #define getrawmonotonic64(ts)		ktime_get_raw_ts64(ts)
255 #define timekeeping_clocktai64(ts)	ktime_get_clocktai_ts64(ts)
256 
257 static inline struct timespec64 current_kernel_time64(void)
258 {
259 	struct timespec64 ts;
260 
261 	ktime_get_coarse_real_ts64(&ts);
262 
263 	return ts;
264 }
265 
266 static inline struct timespec64 get_monotonic_coarse64(void)
267 {
268 	struct timespec64 ts;
269 
270 	ktime_get_coarse_ts64(&ts);
271 
272 	return ts;
273 }
274 
275 #endif
276