xref: /linux-6.15/include/linux/timekeeping.h (revision e00a844a)
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 
36 extern int __getnstimeofday64(struct timespec64 *tv);
37 extern void getnstimeofday64(struct timespec64 *tv);
38 extern void getboottime64(struct timespec64 *ts);
39 
40 #define ktime_get_real_ts64(ts)	getnstimeofday64(ts)
41 
42 /*
43  * ktime_t based interfaces
44  */
45 
46 enum tk_offsets {
47 	TK_OFFS_REAL,
48 	TK_OFFS_BOOT,
49 	TK_OFFS_TAI,
50 	TK_OFFS_MAX,
51 };
52 
53 extern ktime_t ktime_get(void);
54 extern ktime_t ktime_get_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 /**
68  * ktime_get_boottime - Returns monotonic time since boot in ktime_t format
69  *
70  * This is similar to CLOCK_MONTONIC/ktime_get, but also includes the
71  * time spent in suspend.
72  */
73 static inline ktime_t ktime_get_boottime(void)
74 {
75 	return ktime_get_with_offset(TK_OFFS_BOOT);
76 }
77 
78 /**
79  * ktime_get_clocktai - Returns the TAI time of day in ktime_t format
80  */
81 static inline ktime_t ktime_get_clocktai(void)
82 {
83 	return ktime_get_with_offset(TK_OFFS_TAI);
84 }
85 
86 /**
87  * ktime_mono_to_real - Convert monotonic time to clock realtime
88  */
89 static inline ktime_t ktime_mono_to_real(ktime_t mono)
90 {
91 	return ktime_mono_to_any(mono, TK_OFFS_REAL);
92 }
93 
94 static inline u64 ktime_get_ns(void)
95 {
96 	return ktime_to_ns(ktime_get());
97 }
98 
99 static inline u64 ktime_get_real_ns(void)
100 {
101 	return ktime_to_ns(ktime_get_real());
102 }
103 
104 static inline u64 ktime_get_boot_ns(void)
105 {
106 	return ktime_to_ns(ktime_get_boottime());
107 }
108 
109 static inline u64 ktime_get_tai_ns(void)
110 {
111 	return ktime_to_ns(ktime_get_clocktai());
112 }
113 
114 static inline u64 ktime_get_raw_ns(void)
115 {
116 	return ktime_to_ns(ktime_get_raw());
117 }
118 
119 extern u64 ktime_get_mono_fast_ns(void);
120 extern u64 ktime_get_raw_fast_ns(void);
121 extern u64 ktime_get_boot_fast_ns(void);
122 extern u64 ktime_get_real_fast_ns(void);
123 
124 /*
125  * timespec64 interfaces utilizing the ktime based ones
126  */
127 static inline void get_monotonic_boottime64(struct timespec64 *ts)
128 {
129 	*ts = ktime_to_timespec64(ktime_get_boottime());
130 }
131 
132 static inline void timekeeping_clocktai64(struct timespec64 *ts)
133 {
134 	*ts = ktime_to_timespec64(ktime_get_clocktai());
135 }
136 
137 /*
138  * RTC specific
139  */
140 extern bool timekeeping_rtc_skipsuspend(void);
141 extern bool timekeeping_rtc_skipresume(void);
142 
143 extern void timekeeping_inject_sleeptime64(struct timespec64 *delta);
144 
145 /*
146  * struct system_time_snapshot - simultaneous raw/real time capture with
147  *	counter value
148  * @cycles:	Clocksource counter value to produce the system times
149  * @real:	Realtime system time
150  * @raw:	Monotonic raw system time
151  * @clock_was_set_seq:	The sequence number of clock was set events
152  * @cs_was_changed_seq:	The sequence number of clocksource change events
153  */
154 struct system_time_snapshot {
155 	u64		cycles;
156 	ktime_t		real;
157 	ktime_t		raw;
158 	unsigned int	clock_was_set_seq;
159 	u8		cs_was_changed_seq;
160 };
161 
162 /*
163  * struct system_device_crosststamp - system/device cross-timestamp
164  *	(syncronized capture)
165  * @device:		Device time
166  * @sys_realtime:	Realtime simultaneous with device time
167  * @sys_monoraw:	Monotonic raw simultaneous with device time
168  */
169 struct system_device_crosststamp {
170 	ktime_t device;
171 	ktime_t sys_realtime;
172 	ktime_t sys_monoraw;
173 };
174 
175 /*
176  * struct system_counterval_t - system counter value with the pointer to the
177  *	corresponding clocksource
178  * @cycles:	System counter value
179  * @cs:		Clocksource corresponding to system counter value. Used by
180  *	timekeeping code to verify comparibility of two cycle values
181  */
182 struct system_counterval_t {
183 	u64			cycles;
184 	struct clocksource	*cs;
185 };
186 
187 /*
188  * Get cross timestamp between system clock and device clock
189  */
190 extern int get_device_system_crosststamp(
191 			int (*get_time_fn)(ktime_t *device_time,
192 				struct system_counterval_t *system_counterval,
193 				void *ctx),
194 			void *ctx,
195 			struct system_time_snapshot *history,
196 			struct system_device_crosststamp *xtstamp);
197 
198 /*
199  * Simultaneously snapshot realtime and monotonic raw clocks
200  */
201 extern void ktime_get_snapshot(struct system_time_snapshot *systime_snapshot);
202 
203 /*
204  * Persistent clock related interfaces
205  */
206 extern int persistent_clock_is_local;
207 
208 extern void read_persistent_clock64(struct timespec64 *ts);
209 extern void read_boot_clock64(struct timespec64 *ts);
210 extern int update_persistent_clock64(struct timespec64 now);
211 
212 
213 #endif
214