time.h
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1/*
2 * Copyright (c) 2020 Raspberry Pi (Trading) Ltd.
3 *
4 * SPDX-License-Identifier: BSD-3-Clause
5 */
6
7#ifndef _PICO_TIME_H
8#define _PICO_TIME_H
9
10#include "pico.h"
11#include "hardware/timer.h"
12
13#ifdef __cplusplus
14extern "C" {
15#endif
16
32// PICO_CONFIG: PARAM_ASSERTIONS_ENABLED_TIME, Enable/disable assertions in the time module, type=bool, default=0, group=pico_time
33#ifndef PARAM_ASSERTIONS_ENABLED_TIME
34#define PARAM_ASSERTIONS_ENABLED_TIME 0
35#endif
36
37// PICO_CONFIG: PICO_TIME_SLEEP_OVERHEAD_ADJUST_US, How many microseconds to wake up early (and then busy_wait) to account for timer overhead when sleeping in low power mode, type=int, default=6, group=pico_time
38#ifndef PICO_TIME_SLEEP_OVERHEAD_ADJUST_US
39#define PICO_TIME_SLEEP_OVERHEAD_ADJUST_US 6
40#endif
64 return t;
65}
66
67static inline uint32_t us_to_ms(uint64_t us) {
68 if (us >> 32u) {
69 return (uint32_t)(us / 1000u);
70 } else {
71 return ((uint32_t)us) / 1000u;
72 }
73}
74
82static inline uint32_t to_ms_since_boot(absolute_time_t t) {
83 uint64_t us = to_us_since_boot(t);
84 return us_to_ms(us);
85}
86
94static inline absolute_time_t delayed_by_us(const absolute_time_t t, uint64_t us) {
96 uint64_t base = to_us_since_boot(t);
97 uint64_t delayed = base + us;
98 if (delayed < base) {
99 delayed = (uint64_t)-1;
100 }
101 update_us_since_boot(&t2, delayed);
102 return t2;
103}
104
112static inline absolute_time_t delayed_by_ms(const absolute_time_t t, uint32_t ms) {
114 uint64_t base = to_us_since_boot(t);
115 uint64_t delayed = base + ms * 1000ull;
116 if (delayed < base) {
117 delayed = (uint64_t)-1;
118 }
119 update_us_since_boot(&t2, delayed);
120 return t2;
121}
122
129static inline absolute_time_t make_timeout_time_us(uint64_t us) {
130 return delayed_by_us(get_absolute_time(), us);
131}
132
139static inline absolute_time_t make_timeout_time_ms(uint32_t ms) {
140 return delayed_by_ms(get_absolute_time(), ms);
141}
142
155 return (int64_t)(to_us_since_boot(to) - to_us_since_boot(from));
156}
157
164
168extern const absolute_time_t nil_time;
169
176static inline bool is_nil_time(absolute_time_t t) {
177 return !to_us_since_boot(t);
178}
179
209void sleep_until(absolute_time_t target);
210
219void sleep_us(uint64_t us);
220
228void sleep_ms(uint32_t ms);
229
263bool best_effort_wfe_or_timeout(absolute_time_t timeout_timestamp);
264
283// PICO_CONFIG: PICO_TIME_DEFAULT_ALARM_POOL_DISABLED, Disable the default alarm pool, type=bool, default=0, advanced=true, group=pico_time
284#ifndef PICO_TIME_DEFAULT_ALARM_POOL_DISABLED
297#define PICO_TIME_DEFAULT_ALARM_POOL_DISABLED 0
298#endif
299
300// PICO_CONFIG: PICO_TIME_DEFAULT_ALARM_POOL_HARDWARE_ALARM_NUM, Select which HW alarm is used for the default alarm pool, min=0, max=3, default=3, advanced=true, group=pico_time
301#ifndef PICO_TIME_DEFAULT_ALARM_POOL_HARDWARE_ALARM_NUM
307#define PICO_TIME_DEFAULT_ALARM_POOL_HARDWARE_ALARM_NUM 3
308#endif
309
310// PICO_CONFIG: PICO_TIME_DEFAULT_ALARM_POOL_MAX_TIMERS, Selects the maximum number of concurrent timers in the default alarm pool, min=0, max=255, default=16, advanced=true, group=pico_time
311#ifndef PICO_TIME_DEFAULT_ALARM_POOL_MAX_TIMERS
320#define PICO_TIME_DEFAULT_ALARM_POOL_MAX_TIMERS 16
321#endif
322
336typedef int32_t alarm_id_t; // note this is signed because we use -1 as a meaningful error value
337
347typedef int64_t (*alarm_callback_t)(alarm_id_t id, void *user_data);
348
349typedef struct alarm_pool alarm_pool_t;
350
355void alarm_pool_init_default(void);
356
357#if !PICO_TIME_DEFAULT_ALARM_POOL_DISABLED
366#endif
367
386alarm_pool_t *alarm_pool_create(uint hardware_alarm_num, uint max_timers);
387
395
403
427alarm_id_t alarm_pool_add_alarm_at(alarm_pool_t *pool, absolute_time_t time, alarm_callback_t callback, void *user_data, bool fire_if_past);
428
452static inline alarm_id_t alarm_pool_add_alarm_in_us(alarm_pool_t *pool, uint64_t us, alarm_callback_t callback, void *user_data, bool fire_if_past) {
453 return alarm_pool_add_alarm_at(pool, delayed_by_us(get_absolute_time(), us), callback, user_data, fire_if_past);
454}
455
479static inline alarm_id_t alarm_pool_add_alarm_in_ms(alarm_pool_t *pool, uint32_t ms, alarm_callback_t callback, void *user_data, bool fire_if_past) {
480 return alarm_pool_add_alarm_at(pool, delayed_by_ms(get_absolute_time(), ms), callback, user_data, fire_if_past);
481}
482
492
493#if !PICO_TIME_DEFAULT_ALARM_POOL_DISABLED
516static inline alarm_id_t add_alarm_at(absolute_time_t time, alarm_callback_t callback, void *user_data, bool fire_if_past) {
517 return alarm_pool_add_alarm_at(alarm_pool_get_default(), time, callback, user_data, fire_if_past);
518}
519
542static inline alarm_id_t add_alarm_in_us(uint64_t us, alarm_callback_t callback, void *user_data, bool fire_if_past) {
543 return alarm_pool_add_alarm_in_us(alarm_pool_get_default(), us, callback, user_data, fire_if_past);
544}
545
568static inline alarm_id_t add_alarm_in_ms(uint32_t ms, alarm_callback_t callback, void *user_data, bool fire_if_past) {
569 return alarm_pool_add_alarm_in_ms(alarm_pool_get_default(), ms, callback, user_data, fire_if_past);
570}
578static inline bool cancel_alarm(alarm_id_t alarm_id) {
580}
581
582#endif
583
595
603
610 int64_t delay_us;
611 alarm_pool_t *pool;
612 alarm_id_t alarm_id;
614 void *user_data;
615};
616
635bool alarm_pool_add_repeating_timer_us(alarm_pool_t *pool, int64_t delay_us, repeating_timer_callback_t callback, void *user_data, repeating_timer_t *out);
636
655static inline bool alarm_pool_add_repeating_timer_ms(alarm_pool_t *pool, int32_t delay_ms, repeating_timer_callback_t callback, void *user_data, repeating_timer_t *out) {
656 return alarm_pool_add_repeating_timer_us(pool, delay_ms * (int64_t)1000, callback, user_data, out);
657}
658
659#if !PICO_TIME_DEFAULT_ALARM_POOL_DISABLED
677static inline bool add_repeating_timer_us(int64_t delay_us, repeating_timer_callback_t callback, void *user_data, repeating_timer_t *out) {
678 return alarm_pool_add_repeating_timer_us(alarm_pool_get_default(), delay_us, callback, user_data, out);
679}
680
698static inline bool add_repeating_timer_ms(int32_t delay_ms, repeating_timer_callback_t callback, void *user_data, repeating_timer_t *out) {
699 return alarm_pool_add_repeating_timer_us(alarm_pool_get_default(), delay_ms * (int64_t)1000, callback, user_data, out);
700}
701#endif
702
711
712#ifdef __cplusplus
713}
714#endif
715
716#endif
bool alarm_pool_cancel_alarm(alarm_pool_t *pool, alarm_id_t alarm_id)
Cancel an alarm.
Definition: time.c:261
static alarm_id_t alarm_pool_add_alarm_in_us(alarm_pool_t *pool, uint64_t us, alarm_callback_t callback, void *user_data, bool fire_if_past)
Add an alarm callback to be called after a delay specified in microseconds.
Definition: time.h:452
alarm_pool_t * alarm_pool_create(uint hardware_alarm_num, uint max_timers)
Create an alarm pool.
Definition: time.c:178
uint alarm_pool_hardware_alarm_num(alarm_pool_t *pool)
Return the hardware alarm used by an alarm pool.
Definition: time.c:285
alarm_pool_t * alarm_pool_get_default(void)
The default alarm pool used when alarms are added without specifying an alarm pool,...
Definition: time.c:91
static alarm_id_t add_alarm_in_us(uint64_t us, alarm_callback_t callback, void *user_data, bool fire_if_past)
Add an alarm callback to be called after a delay specified in microseconds.
Definition: time.h:542
static alarm_id_t alarm_pool_add_alarm_in_ms(alarm_pool_t *pool, uint32_t ms, alarm_callback_t callback, void *user_data, bool fire_if_past)
Add an alarm callback to be called after a delay specified in milliseconds.
Definition: time.h:479
static alarm_id_t add_alarm_in_ms(uint32_t ms, alarm_callback_t callback, void *user_data, bool fire_if_past)
Add an alarm callback to be called after a delay specified in milliseconds.
Definition: time.h:568
int32_t alarm_id_t
The identifier for an alarm.
Definition: time.h:336
void alarm_pool_init_default(void)
Create the default alarm pool (if not already created or disabled)
Definition: time.c:77
alarm_id_t alarm_pool_add_alarm_at(alarm_pool_t *pool, absolute_time_t time, alarm_callback_t callback, void *user_data, bool fire_if_past)
Add an alarm callback to be called at a specific time.
Definition: time.c:214
int64_t(* alarm_callback_t)(alarm_id_t id, void *user_data)
User alarm callback.
Definition: time.h:347
void alarm_pool_destroy(alarm_pool_t *pool)
Destroy the alarm pool, cancelling all alarms and freeing up the underlying hardware alarm.
Definition: time.c:196
static alarm_id_t add_alarm_at(absolute_time_t time, alarm_callback_t callback, void *user_data, bool fire_if_past)
Add an alarm callback to be called at a specific time.
Definition: time.h:516
static bool cancel_alarm(alarm_id_t alarm_id)
Cancel an alarm from the default alarm pool.
Definition: time.h:578
uint64_t PICO_WEAK_FUNCTION_IMPL_NAME() time_us_64()
Return the current 64 bit timestamp value in microseconds.
Definition: timer.c:33
static bool add_repeating_timer_ms(int32_t delay_ms, repeating_timer_callback_t callback, void *user_data, repeating_timer_t *out)
Add a repeating timer that is called repeatedly at the specified interval in milliseconds.
Definition: time.h:698
bool(* repeating_timer_callback_t)(repeating_timer_t *rt)
Callback for a repeating timer.
Definition: time.h:602
bool alarm_pool_add_repeating_timer_us(alarm_pool_t *pool, int64_t delay_us, repeating_timer_callback_t callback, void *user_data, repeating_timer_t *out)
Add a repeating timer that is called repeatedly at the specified interval in microseconds.
Definition: time.c:309
static bool add_repeating_timer_us(int64_t delay_us, repeating_timer_callback_t callback, void *user_data, repeating_timer_t *out)
Add a repeating timer that is called repeatedly at the specified interval in microseconds.
Definition: time.h:677
bool cancel_repeating_timer(repeating_timer_t *timer)
Cancel a repeating timer.
Definition: time.c:322
static bool alarm_pool_add_repeating_timer_ms(alarm_pool_t *pool, int32_t delay_ms, repeating_timer_callback_t callback, void *user_data, repeating_timer_t *out)
Add a repeating timer that is called repeatedly at the specified interval in milliseconds.
Definition: time.h:655
void sleep_until(absolute_time_t target)
Wait until after the given timestamp to return.
Definition: time.c:345
void sleep_ms(uint32_t ms)
Wait for the given number of milliseconds before returning.
Definition: time.c:392
bool best_effort_wfe_or_timeout(absolute_time_t timeout_timestamp)
Helper method for blocking on a timeout.
Definition: time.c:396
void sleep_us(uint64_t us)
Wait for the given number of microseconds before returning.
Definition: time.c:375
static bool is_nil_time(absolute_time_t t)
Determine if the given timestamp is nil.
Definition: time.h:176
static uint64_t to_us_since_boot(absolute_time_t t)
convert an absolute_time_t into a number of microseconds since boot.
Definition: types.h:44
static int64_t absolute_time_diff_us(absolute_time_t from, absolute_time_t to)
Return the difference in microseconds between two timestamps.
Definition: time.h:154
static absolute_time_t get_absolute_time(void)
Return a representation of the current time.
Definition: time.h:61
static absolute_time_t make_timeout_time_us(uint64_t us)
Convenience method to get the timestamp a number of microseconds from the current time.
Definition: time.h:129
static absolute_time_t delayed_by_us(const absolute_time_t t, uint64_t us)
Return a timestamp value obtained by adding a number of microseconds to another timestamp.
Definition: time.h:94
static absolute_time_t delayed_by_ms(const absolute_time_t t, uint32_t ms)
Return a timestamp value obtained by adding a number of milliseconds to another timestamp.
Definition: time.h:112
const absolute_time_t nil_time
The timestamp representing a null timestamp.
static absolute_time_t make_timeout_time_ms(uint32_t ms)
Convenience method to get the timestamp a number of milliseconds from the current time.
Definition: time.h:139
static uint32_t to_ms_since_boot(absolute_time_t t)
Convert a timestamp into a number of milliseconds since boot.
Definition: time.h:82
const absolute_time_t at_the_end_of_time
The timestamp representing the end of time; this is actually not the maximum possible timestamp,...
static void update_us_since_boot(absolute_time_t *t, uint64_t us_since_boot)
update an absolute_time_t value to represent a given number of microseconds since boot
Definition: types.h:59
Definition: types.h:33
Definition: time.c:25
Information about a repeating timer.
Definition: time.h:609