xref: /linux-6.15/include/linux/timekeeping.h (revision 5ecd9d40)
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 void ktime_get_active_ts64(struct timespec64 *ts);
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 /* Clock BOOTTIME compatibility wrappers */
44 static inline void get_monotonic_boottime64(struct timespec64 *ts)
45 {
46 	ktime_get_ts64(ts);
47 }
48 
49 /*
50  * ktime_t based interfaces
51  */
52 enum tk_offsets {
53 	TK_OFFS_REAL,
54 	TK_OFFS_TAI,
55 	TK_OFFS_MAX,
56 };
57 
58 extern ktime_t ktime_get(void);
59 extern ktime_t ktime_get_with_offset(enum tk_offsets offs);
60 extern ktime_t ktime_mono_to_any(ktime_t tmono, enum tk_offsets offs);
61 extern ktime_t ktime_get_raw(void);
62 extern u32 ktime_get_resolution_ns(void);
63 
64 /* Clock BOOTTIME compatibility wrappers */
65 static inline ktime_t ktime_get_boottime(void) { return ktime_get(); }
66 static inline u64 ktime_get_boot_ns(void) { return ktime_get(); }
67 
68 /**
69  * ktime_get_real - get the real (wall-) time in ktime_t format
70  */
71 static inline ktime_t ktime_get_real(void)
72 {
73 	return ktime_get_with_offset(TK_OFFS_REAL);
74 }
75 
76 /**
77  * ktime_get_clocktai - Returns the TAI time of day in ktime_t format
78  */
79 static inline ktime_t ktime_get_clocktai(void)
80 {
81 	return ktime_get_with_offset(TK_OFFS_TAI);
82 }
83 
84 /**
85  * ktime_mono_to_real - Convert monotonic time to clock realtime
86  */
87 static inline ktime_t ktime_mono_to_real(ktime_t mono)
88 {
89 	return ktime_mono_to_any(mono, TK_OFFS_REAL);
90 }
91 
92 static inline u64 ktime_get_ns(void)
93 {
94 	return ktime_to_ns(ktime_get());
95 }
96 
97 static inline u64 ktime_get_real_ns(void)
98 {
99 	return ktime_to_ns(ktime_get_real());
100 }
101 
102 static inline u64 ktime_get_tai_ns(void)
103 {
104 	return ktime_to_ns(ktime_get_clocktai());
105 }
106 
107 static inline u64 ktime_get_raw_ns(void)
108 {
109 	return ktime_to_ns(ktime_get_raw());
110 }
111 
112 extern u64 ktime_get_mono_fast_ns(void);
113 extern u64 ktime_get_raw_fast_ns(void);
114 extern u64 ktime_get_real_fast_ns(void);
115 
116 /*
117  * timespec64 interfaces utilizing the ktime based ones
118  */
119 static inline void timekeeping_clocktai64(struct timespec64 *ts)
120 {
121 	*ts = ktime_to_timespec64(ktime_get_clocktai());
122 }
123 
124 /*
125  * RTC specific
126  */
127 extern bool timekeeping_rtc_skipsuspend(void);
128 extern bool timekeeping_rtc_skipresume(void);
129 
130 extern void timekeeping_inject_sleeptime64(struct timespec64 *delta);
131 
132 /*
133  * struct system_time_snapshot - simultaneous raw/real time capture with
134  *	counter value
135  * @cycles:	Clocksource counter value to produce the system times
136  * @real:	Realtime system time
137  * @raw:	Monotonic raw system time
138  * @clock_was_set_seq:	The sequence number of clock was set events
139  * @cs_was_changed_seq:	The sequence number of clocksource change events
140  */
141 struct system_time_snapshot {
142 	u64		cycles;
143 	ktime_t		real;
144 	ktime_t		raw;
145 	unsigned int	clock_was_set_seq;
146 	u8		cs_was_changed_seq;
147 };
148 
149 /*
150  * struct system_device_crosststamp - system/device cross-timestamp
151  *	(syncronized capture)
152  * @device:		Device time
153  * @sys_realtime:	Realtime simultaneous with device time
154  * @sys_monoraw:	Monotonic raw simultaneous with device time
155  */
156 struct system_device_crosststamp {
157 	ktime_t device;
158 	ktime_t sys_realtime;
159 	ktime_t sys_monoraw;
160 };
161 
162 /*
163  * struct system_counterval_t - system counter value with the pointer to the
164  *	corresponding clocksource
165  * @cycles:	System counter value
166  * @cs:		Clocksource corresponding to system counter value. Used by
167  *	timekeeping code to verify comparibility of two cycle values
168  */
169 struct system_counterval_t {
170 	u64			cycles;
171 	struct clocksource	*cs;
172 };
173 
174 /*
175  * Get cross timestamp between system clock and device clock
176  */
177 extern int get_device_system_crosststamp(
178 			int (*get_time_fn)(ktime_t *device_time,
179 				struct system_counterval_t *system_counterval,
180 				void *ctx),
181 			void *ctx,
182 			struct system_time_snapshot *history,
183 			struct system_device_crosststamp *xtstamp);
184 
185 /*
186  * Simultaneously snapshot realtime and monotonic raw clocks
187  */
188 extern void ktime_get_snapshot(struct system_time_snapshot *systime_snapshot);
189 
190 /*
191  * Persistent clock related interfaces
192  */
193 extern int persistent_clock_is_local;
194 
195 extern void read_persistent_clock64(struct timespec64 *ts);
196 extern void read_boot_clock64(struct timespec64 *ts);
197 extern int update_persistent_clock64(struct timespec64 now);
198 
199 
200 #endif
201