Zephyr API Documentation 4.2.0
A Scalable Open Source RTOS
 4.2.0
clock.h
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1/*
2 * Copyright (c) 2014-2015 Wind River Systems, Inc.
3 * Copyright (c) 2025 Tenstorrent AI ULC
4 *
5 * SPDX-License-Identifier: Apache-2.0
6 */
7
17
18#ifndef ZEPHYR_INCLUDE_SYS_CLOCK_H_
19#define ZEPHYR_INCLUDE_SYS_CLOCK_H_
20
21#include <zephyr/sys/dlist.h>
23#include <zephyr/sys/util.h>
24#include <zephyr/toolchain.h>
25#include <zephyr/types.h>
26
27#ifdef __cplusplus
28extern "C" {
29#endif
30
35
45#ifdef CONFIG_TIMEOUT_64BIT
46typedef int64_t k_ticks_t;
47#else
49#endif
50
51#define K_TICKS_FOREVER ((k_ticks_t)(-1))
52
65typedef struct {
68
80#define K_TIMEOUT_EQ(a, b) ((a).ticks == (b).ticks)
81
83#define NSEC_PER_USEC 1000U
84
86#define NSEC_PER_MSEC 1000000U
87
89#define USEC_PER_MSEC 1000U
90
92#define MSEC_PER_SEC 1000U
93
95#define SEC_PER_MIN 60U
96
98#define SEC_PER_HOUR 3600U
99
101#define SEC_PER_DAY 86400U
102
104#define MIN_PER_HOUR 60U
105
107#define HOUR_PER_DAY 24U
108
110#define USEC_PER_SEC ((USEC_PER_MSEC) * (MSEC_PER_SEC))
111
113#define NSEC_PER_SEC ((NSEC_PER_USEC) * (USEC_PER_MSEC) * (MSEC_PER_SEC))
114
116
118#define Z_TIMEOUT_NO_WAIT_INIT {0}
119#define Z_TIMEOUT_NO_WAIT ((k_timeout_t)Z_TIMEOUT_NO_WAIT_INIT)
120#if defined(__cplusplus) && ((__cplusplus - 0) < 202002L)
121#define Z_TIMEOUT_TICKS_INIT(t) {(t)}
122#else
123#define Z_TIMEOUT_TICKS_INIT(t) {.ticks = (t)}
124#endif
125#define Z_TIMEOUT_TICKS(t) ((k_timeout_t)Z_TIMEOUT_TICKS_INIT(t))
126#define Z_FOREVER Z_TIMEOUT_TICKS(K_TICKS_FOREVER)
127
128#ifdef CONFIG_TIMEOUT_64BIT
129#define Z_TIMEOUT_MS(t) Z_TIMEOUT_TICKS((k_ticks_t)k_ms_to_ticks_ceil64(MAX(t, 0)))
130#define Z_TIMEOUT_US(t) Z_TIMEOUT_TICKS((k_ticks_t)k_us_to_ticks_ceil64(MAX(t, 0)))
131#define Z_TIMEOUT_NS(t) Z_TIMEOUT_TICKS((k_ticks_t)k_ns_to_ticks_ceil64(MAX(t, 0)))
132#define Z_TIMEOUT_CYC(t) Z_TIMEOUT_TICKS((k_ticks_t)k_cyc_to_ticks_ceil64(MAX(t, 0)))
133#define Z_TIMEOUT_MS_TICKS(t) ((k_ticks_t)k_ms_to_ticks_ceil64(MAX(t, 0)))
134#else
135#define Z_TIMEOUT_MS(t) Z_TIMEOUT_TICKS((k_ticks_t)k_ms_to_ticks_ceil32(MAX(t, 0)))
136#define Z_TIMEOUT_US(t) Z_TIMEOUT_TICKS((k_ticks_t)k_us_to_ticks_ceil32(MAX(t, 0)))
137#define Z_TIMEOUT_NS(t) Z_TIMEOUT_TICKS((k_ticks_t)k_ns_to_ticks_ceil32(MAX(t, 0)))
138#define Z_TIMEOUT_CYC(t) Z_TIMEOUT_TICKS((k_ticks_t)k_cyc_to_ticks_ceil32(MAX(t, 0)))
139#define Z_TIMEOUT_MS_TICKS(t) ((k_ticks_t)k_ms_to_ticks_ceil32(MAX(t, 0)))
140#endif
141
142/* Converts between absolute timeout expiration values (packed into
143 * the negative space below K_TICKS_FOREVER) and (non-negative) delta
144 * timeout values. If the result of Z_TICK_ABS(t) is >= 0, then the
145 * value was an absolute timeout with the returned expiration time.
146 * Note that this macro is bidirectional: Z_TICK_ABS(Z_TICK_ABS(t)) ==
147 * t for all inputs, and that the representation of K_TICKS_FOREVER is
148 * the same value in both spaces! Clever, huh?
149 */
150#define Z_TICK_ABS(t) (K_TICKS_FOREVER - 1 - (t))
151
152/* Test for relative timeout */
153#if CONFIG_TIMEOUT_64BIT
154/* Positive values are relative/delta timeouts and negative values are absolute
155 * timeouts, except -1 which is reserved for K_TIMEOUT_FOREVER. 0 is K_NO_WAIT,
156 * which is historically considered a relative timeout.
157 * K_TIMEOUT_FOREVER is not considered a relative timeout and neither is it
158 * considerd an absolute timeouts (so !Z_IS_TIMEOUT_RELATIVE() does not
159 * necessarily mean it is an absolute timeout if ticks == -1);
160 */
161#define Z_IS_TIMEOUT_RELATIVE(timeout) (((timeout).ticks) >= 0)
162#else
163#define Z_IS_TIMEOUT_RELATIVE(timeout) true
164#endif
165
166/* added tick needed to account for tick in progress */
167#define _TICK_ALIGN 1
168
170
171#ifndef CONFIG_TIMER_READS_ITS_FREQUENCY_AT_RUNTIME
172#if defined(CONFIG_SYS_CLOCK_EXISTS)
173#if CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC == 0
174#error "SYS_CLOCK_HW_CYCLES_PER_SEC must be non-zero!"
175#endif /* CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC == 0 */
176#endif /* CONFIG_SYS_CLOCK_EXISTS */
177#endif /* CONFIG_TIMER_READS_ITS_FREQUENCY_AT_RUNTIME */
178
179/* kernel clocks */
180
181/*
182 * We default to using 64-bit intermediates in timescale conversions,
183 * but if the HW timer cycles/sec, ticks/sec and ms/sec are all known
184 * to be nicely related, then we can cheat with 32 bits instead.
185 */
190
191#ifdef CONFIG_SYS_CLOCK_EXISTS
192
193#if defined(CONFIG_TIMER_READS_ITS_FREQUENCY_AT_RUNTIME) || \
194 (MSEC_PER_SEC % CONFIG_SYS_CLOCK_TICKS_PER_SEC) || \
195 (CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC % CONFIG_SYS_CLOCK_TICKS_PER_SEC)
196#define _NEED_PRECISE_TICK_MS_CONVERSION
197#endif
198
199#endif
200
205#define SYS_CLOCK_HW_CYCLES_TO_NS_AVG(X, NCYCLES) (uint32_t)(k_cyc_to_ns_floor64(X) / NCYCLES)
206
215
224
225#ifndef CONFIG_SYS_CLOCK_EXISTS
226#define sys_clock_tick_get() (0)
227#define sys_clock_tick_get_32() (0)
228#endif
229
230#ifdef CONFIG_SYS_CLOCK_EXISTS
231
242typedef struct {
245
263
278
290{
291 if (a.tick == b.tick) {
292 return 0;
293 }
294 return a.tick < b.tick ? -1 : 1;
295}
296
297#else
298
299/*
300 * When timers are configured out, timepoints can't relate to anything.
301 * The best we can do is to preserve whether or not they are derived from
302 * K_NO_WAIT. Anything else will translate back to K_FOREVER.
303 */
304typedef struct {
305 bool wait;
307
308static inline k_timepoint_t sys_timepoint_calc(k_timeout_t timeout)
309{
310 k_timepoint_t timepoint;
311
312 timepoint.wait = !K_TIMEOUT_EQ(timeout, Z_TIMEOUT_NO_WAIT);
313 return timepoint;
314}
315
316static inline k_timeout_t sys_timepoint_timeout(k_timepoint_t timepoint)
317{
318 return timepoint.wait ? Z_FOREVER : Z_TIMEOUT_NO_WAIT;
319}
320
321static inline int sys_timepoint_cmp(k_timepoint_t a, k_timepoint_t b)
322{
323 if (a.wait == b.wait) {
324 return 0;
325 }
326 return b.wait ? -1 : 1;
327}
328
329#endif
330
339static inline bool sys_timepoint_expired(k_timepoint_t timepoint)
340{
341 return K_TIMEOUT_EQ(sys_timepoint_timeout(timepoint), Z_TIMEOUT_NO_WAIT);
342}
343
345
350
360#define SYS_CLOCK_REALTIME 1
361
368#define SYS_CLOCK_MONOTONIC 4
369
376#define SYS_TIMER_ABSTIME 4
377
379/* forward declaration as workaround for time.h */
380struct timespec;
382
399__syscall void sys_clock_getrtoffset(struct timespec *tp);
400
409int sys_clock_gettime(int clock_id, struct timespec *tp);
410
420__syscall int sys_clock_settime(int clock_id, const struct timespec *tp);
421
447__syscall int sys_clock_nanosleep(int clock_id, int flags, const struct timespec *rqtp,
448 struct timespec *rmtp);
449
453
454#ifndef CONFIG_BOARD_UNIT_TESTING
455#include <zephyr/syscalls/clock.h>
456#endif
457
458#ifdef __cplusplus
459}
460#endif
461
462#endif /* ZEPHYR_INCLUDE_SYS_CLOCK_H_ */
int sys_clock_nanosleep(int clock_id, int flags, const struct timespec *rqtp, struct timespec *rmtp)
Sleep for the specified amount of time with respect to the specified clock.
int sys_clock_settime(int clock_id, const struct timespec *tp)
Set the current time for the specified clock.
uint32_t sys_clock_tick_get_32(void)
Return the lower part of the current system tick count.
k_timepoint_t sys_timepoint_calc(k_timeout_t timeout)
Calculate a timepoint value.
int64_t sys_clock_tick_get(void)
Return the current system tick count.
k_timeout_t sys_timepoint_timeout(k_timepoint_t timepoint)
Remaining time to given timepoint.
static bool sys_timepoint_expired(k_timepoint_t timepoint)
Indicates if timepoint is expired.
Definition clock.h:339
int sys_clock_gettime(int clock_id, struct timespec *tp)
Get the current time from the specified clock.
uint32_t k_ticks_t
Tick precision used in timeout APIs.
Definition clock.h:48
#define K_TIMEOUT_EQ(a, b)
Compare timeouts for equality.
Definition clock.h:80
void sys_clock_getrtoffset(struct timespec *tp)
INTERNAL_HIDDEN.
static int sys_timepoint_cmp(k_timepoint_t a, k_timepoint_t b)
Compare two timepoint values.
Definition clock.h:289
flags
Definition parser.h:97
__UINT32_TYPE__ uint32_t
Definition stdint.h:90
__UINT64_TYPE__ uint64_t
Definition stdint.h:91
__INT64_TYPE__ int64_t
Definition stdint.h:75
Kernel timeout type.
Definition clock.h:65
k_ticks_t ticks
Definition clock.h:66
Kernel timepoint type.
Definition clock.h:242
uint64_t tick
Definition clock.h:243
Definition _timespec.h:22
Misc utilities.
Macros to abstract toolchain specific capabilities.