xref: /linux-6.15/include/linux/timekeeping.h (revision 00a62703)
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  * Kernel time accessors
24  */
25 struct timespec64 current_kernel_time64(void);
26 
27 /*
28  * timespec64 based interfaces
29  */
30 struct timespec64 get_monotonic_coarse64(void);
31 extern void getrawmonotonic64(struct timespec64 *ts);
32 extern void ktime_get_ts64(struct timespec64 *ts);
33 extern time64_t ktime_get_seconds(void);
34 extern time64_t __ktime_get_real_seconds(void);
35 extern time64_t ktime_get_real_seconds(void);
36 
37 extern int __getnstimeofday64(struct timespec64 *tv);
38 extern void getnstimeofday64(struct timespec64 *tv);
39 extern void getboottime64(struct timespec64 *ts);
40 
41 #define ktime_get_real_ts64(ts)	getnstimeofday64(ts)
42 
43 /*
44  * ktime_t based interfaces
45  */
46 
47 enum tk_offsets {
48 	TK_OFFS_REAL,
49 	TK_OFFS_BOOT,
50 	TK_OFFS_TAI,
51 	TK_OFFS_MAX,
52 };
53 
54 extern ktime_t ktime_get(void);
55 extern ktime_t ktime_get_with_offset(enum tk_offsets offs);
56 extern ktime_t ktime_mono_to_any(ktime_t tmono, enum tk_offsets offs);
57 extern ktime_t ktime_get_raw(void);
58 extern u32 ktime_get_resolution_ns(void);
59 
60 /**
61  * ktime_get_real - get the real (wall-) time in ktime_t format
62  */
63 static inline ktime_t ktime_get_real(void)
64 {
65 	return ktime_get_with_offset(TK_OFFS_REAL);
66 }
67 
68 /**
69  * ktime_get_boottime - Returns monotonic time since boot in ktime_t format
70  *
71  * This is similar to CLOCK_MONTONIC/ktime_get, but also includes the
72  * time spent in suspend.
73  */
74 static inline ktime_t ktime_get_boottime(void)
75 {
76 	return ktime_get_with_offset(TK_OFFS_BOOT);
77 }
78 
79 /**
80  * ktime_get_clocktai - Returns the TAI time of day in ktime_t format
81  */
82 static inline ktime_t ktime_get_clocktai(void)
83 {
84 	return ktime_get_with_offset(TK_OFFS_TAI);
85 }
86 
87 /**
88  * ktime_mono_to_real - Convert monotonic time to clock realtime
89  */
90 static inline ktime_t ktime_mono_to_real(ktime_t mono)
91 {
92 	return ktime_mono_to_any(mono, TK_OFFS_REAL);
93 }
94 
95 static inline u64 ktime_get_ns(void)
96 {
97 	return ktime_to_ns(ktime_get());
98 }
99 
100 static inline u64 ktime_get_real_ns(void)
101 {
102 	return ktime_to_ns(ktime_get_real());
103 }
104 
105 static inline u64 ktime_get_boot_ns(void)
106 {
107 	return ktime_to_ns(ktime_get_boottime());
108 }
109 
110 static inline u64 ktime_get_tai_ns(void)
111 {
112 	return ktime_to_ns(ktime_get_clocktai());
113 }
114 
115 static inline u64 ktime_get_raw_ns(void)
116 {
117 	return ktime_to_ns(ktime_get_raw());
118 }
119 
120 extern u64 ktime_get_mono_fast_ns(void);
121 extern u64 ktime_get_raw_fast_ns(void);
122 extern u64 ktime_get_boot_fast_ns(void);
123 extern u64 ktime_get_real_fast_ns(void);
124 
125 /*
126  * timespec64 interfaces utilizing the ktime based ones
127  */
128 static inline void get_monotonic_boottime64(struct timespec64 *ts)
129 {
130 	*ts = ktime_to_timespec64(ktime_get_boottime());
131 }
132 
133 static inline void timekeeping_clocktai64(struct timespec64 *ts)
134 {
135 	*ts = ktime_to_timespec64(ktime_get_clocktai());
136 }
137 
138 /*
139  * RTC specific
140  */
141 extern bool timekeeping_rtc_skipsuspend(void);
142 extern bool timekeeping_rtc_skipresume(void);
143 
144 extern void timekeeping_inject_sleeptime64(struct timespec64 *delta);
145 
146 /*
147  * struct system_time_snapshot - simultaneous raw/real time capture with
148  *	counter value
149  * @cycles:	Clocksource counter value to produce the system times
150  * @real:	Realtime system time
151  * @raw:	Monotonic raw system time
152  * @clock_was_set_seq:	The sequence number of clock was set events
153  * @cs_was_changed_seq:	The sequence number of clocksource change events
154  */
155 struct system_time_snapshot {
156 	u64		cycles;
157 	ktime_t		real;
158 	ktime_t		raw;
159 	unsigned int	clock_was_set_seq;
160 	u8		cs_was_changed_seq;
161 };
162 
163 /*
164  * struct system_device_crosststamp - system/device cross-timestamp
165  *	(syncronized capture)
166  * @device:		Device time
167  * @sys_realtime:	Realtime simultaneous with device time
168  * @sys_monoraw:	Monotonic raw simultaneous with device time
169  */
170 struct system_device_crosststamp {
171 	ktime_t device;
172 	ktime_t sys_realtime;
173 	ktime_t sys_monoraw;
174 };
175 
176 /*
177  * struct system_counterval_t - system counter value with the pointer to the
178  *	corresponding clocksource
179  * @cycles:	System counter value
180  * @cs:		Clocksource corresponding to system counter value. Used by
181  *	timekeeping code to verify comparibility of two cycle values
182  */
183 struct system_counterval_t {
184 	u64			cycles;
185 	struct clocksource	*cs;
186 };
187 
188 /*
189  * Get cross timestamp between system clock and device clock
190  */
191 extern int get_device_system_crosststamp(
192 			int (*get_time_fn)(ktime_t *device_time,
193 				struct system_counterval_t *system_counterval,
194 				void *ctx),
195 			void *ctx,
196 			struct system_time_snapshot *history,
197 			struct system_device_crosststamp *xtstamp);
198 
199 /*
200  * Simultaneously snapshot realtime and monotonic raw clocks
201  */
202 extern void ktime_get_snapshot(struct system_time_snapshot *systime_snapshot);
203 
204 /*
205  * Persistent clock related interfaces
206  */
207 extern int persistent_clock_is_local;
208 
209 extern void read_persistent_clock64(struct timespec64 *ts);
210 extern void read_boot_clock64(struct timespec64 *ts);
211 extern int update_persistent_clock64(struct timespec64 now);
212 
213 
214 #endif
215