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/*
* Copyright (c) 2014-2015 Wind River Systems, Inc.
*
* SPDX-License-Identifier: Apache-2.0
*/
/**
* @file
* @brief Variables needed for system clock
*
*
* Declare variables used by both system timer device driver and kernel
* components that use timer functionality.
*/
#ifndef ZEPHYR_INCLUDE_SYS_CLOCK_H_
#define ZEPHYR_INCLUDE_SYS_CLOCK_H_
#include <zephyr/sys/util.h>
#include <zephyr/sys/dlist.h>
#include <zephyr/toolchain.h>
#include <zephyr/types.h>
#include <zephyr/sys/time_units.h>
#ifdef __cplusplus
extern "C" {
#endif
/**
* @addtogroup clock_apis
* @{
*/
/**
* @brief Tick precision used in timeout APIs
*
* This type defines the word size of the timeout values used in
* k_timeout_t objects, and thus defines an upper bound on maximum
* timeout length (or equivalently minimum tick duration). Note that
* this does not affect the size of the system uptime counter, which
* is always a 64 bit count of ticks.
*/
#ifdef CONFIG_TIMEOUT_64BIT
typedef int64_t k_ticks_t;
#else
typedef uint32_t k_ticks_t;
#endif
#define K_TICKS_FOREVER ((k_ticks_t) -1)
/**
* @brief Kernel timeout type
*
* Timeout arguments presented to kernel APIs are stored in this
* opaque type, which is capable of representing times in various
* formats and units. It should be constructed from application data
* using one of the macros defined for this purpose (e.g. `K_MSEC()`,
* `K_TIMEOUT_ABS_TICKS()`, etc...), or be one of the two constants
* K_NO_WAIT or K_FOREVER. Applications should not inspect the
* internal data once constructed. Timeout values may be compared for
* equality with the `K_TIMEOUT_EQ()` macro.
*/
typedef struct {
k_ticks_t ticks;
} k_timeout_t;
/**
* @brief Compare timeouts for equality
*
* The k_timeout_t object is an opaque struct that should not be
* inspected by application code. This macro exists so that users can
* test timeout objects for equality with known constants
* (e.g. K_NO_WAIT and K_FOREVER) when implementing their own APIs in
* terms of Zephyr timeout constants.
*
* @return True if the timeout objects are identical
*/
#define K_TIMEOUT_EQ(a, b) ((a).ticks == (b).ticks)
/** number of nanoseconds per micorsecond */
#define NSEC_PER_USEC 1000U
/** number of nanoseconds per millisecond */
#define NSEC_PER_MSEC 1000000U
/** number of microseconds per millisecond */
#define USEC_PER_MSEC 1000U
/** number of milliseconds per second */
#define MSEC_PER_SEC 1000U
/** number of seconds per minute */
#define SEC_PER_MIN 60U
/** number of minutes per hour */
#define MIN_PER_HOUR 60U
/** number of hours per day */
#define HOUR_PER_DAY 24U
/** number of microseconds per second */
#define USEC_PER_SEC ((USEC_PER_MSEC) * (MSEC_PER_SEC))
/** number of nanoseconds per second */
#define NSEC_PER_SEC ((NSEC_PER_USEC) * (USEC_PER_MSEC) * (MSEC_PER_SEC))
/** @} */
/** @cond INTERNAL_HIDDEN */
#define Z_TIMEOUT_NO_WAIT ((k_timeout_t) {0})
#if defined(__cplusplus) && ((__cplusplus - 0) < 202002L)
#define Z_TIMEOUT_TICKS(t) ((k_timeout_t) { (t) })
#else
#define Z_TIMEOUT_TICKS(t) ((k_timeout_t) { .ticks = (t) })
#endif
#define Z_FOREVER Z_TIMEOUT_TICKS(K_TICKS_FOREVER)
#ifdef CONFIG_TIMEOUT_64BIT
# define Z_TIMEOUT_MS(t) Z_TIMEOUT_TICKS((k_ticks_t)k_ms_to_ticks_ceil64(MAX(t, 0)))
# define Z_TIMEOUT_US(t) Z_TIMEOUT_TICKS((k_ticks_t)k_us_to_ticks_ceil64(MAX(t, 0)))
# define Z_TIMEOUT_NS(t) Z_TIMEOUT_TICKS((k_ticks_t)k_ns_to_ticks_ceil64(MAX(t, 0)))
# define Z_TIMEOUT_CYC(t) Z_TIMEOUT_TICKS((k_ticks_t)k_cyc_to_ticks_ceil64(MAX(t, 0)))
# define Z_TIMEOUT_MS_TICKS(t) ((k_ticks_t)k_ms_to_ticks_ceil64(MAX(t, 0)))
#else
# define Z_TIMEOUT_MS(t) Z_TIMEOUT_TICKS((k_ticks_t)k_ms_to_ticks_ceil32(MAX(t, 0)))
# define Z_TIMEOUT_US(t) Z_TIMEOUT_TICKS((k_ticks_t)k_us_to_ticks_ceil32(MAX(t, 0)))
# define Z_TIMEOUT_NS(t) Z_TIMEOUT_TICKS((k_ticks_t)k_ns_to_ticks_ceil32(MAX(t, 0)))
# define Z_TIMEOUT_CYC(t) Z_TIMEOUT_TICKS((k_ticks_t)k_cyc_to_ticks_ceil32(MAX(t, 0)))
# define Z_TIMEOUT_MS_TICKS(t) ((k_ticks_t)k_ms_to_ticks_ceil32(MAX(t, 0)))
#endif
/* Converts between absolute timeout expiration values (packed into
* the negative space below K_TICKS_FOREVER) and (non-negative) delta
* timeout values. If the result of Z_TICK_ABS(t) is >= 0, then the
* value was an absolute timeout with the returned expiration time.
* Note that this macro is bidirectional: Z_TICK_ABS(Z_TICK_ABS(t)) ==
* t for all inputs, and that the representation of K_TICKS_FOREVER is
* the same value in both spaces! Clever, huh?
*/
#define Z_TICK_ABS(t) (K_TICKS_FOREVER - 1 - (t))
/* added tick needed to account for tick in progress */
#define _TICK_ALIGN 1
/** @endcond */
#if defined(CONFIG_SYS_CLOCK_EXISTS) && \
(CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC == 0)
#error "SYS_CLOCK_HW_CYCLES_PER_SEC must be non-zero!"
#endif
/* kernel clocks */
/*
* We default to using 64-bit intermediates in timescale conversions,
* but if the HW timer cycles/sec, ticks/sec and ms/sec are all known
* to be nicely related, then we can cheat with 32 bits instead.
*/
/**
* @addtogroup clock_apis
* @{
*/
#ifdef CONFIG_SYS_CLOCK_EXISTS
#if defined(CONFIG_TIMER_READS_ITS_FREQUENCY_AT_RUNTIME) || \
(MSEC_PER_SEC % CONFIG_SYS_CLOCK_TICKS_PER_SEC) || \
(CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC % CONFIG_SYS_CLOCK_TICKS_PER_SEC)
#define _NEED_PRECISE_TICK_MS_CONVERSION
#endif
#endif
/**
* SYS_CLOCK_HW_CYCLES_TO_NS_AVG converts CPU clock cycles to nanoseconds
* and calculates the average cycle time
*/
#define SYS_CLOCK_HW_CYCLES_TO_NS_AVG(X, NCYCLES) \
(uint32_t)(k_cyc_to_ns_floor64(X) / NCYCLES)
/**
*
* @brief Return the lower part of the current system tick count
*
* @return the current system tick count
*
*/
uint32_t sys_clock_tick_get_32(void);
/**
*
* @brief Return the current system tick count
*
* @return the current system tick count
*
*/
int64_t sys_clock_tick_get(void);
#ifndef CONFIG_SYS_CLOCK_EXISTS
#define sys_clock_tick_get() (0)
#define sys_clock_tick_get_32() (0)
#endif
#ifdef CONFIG_SYS_CLOCK_EXISTS
/**
* @brief Kernel timepoint type
*
* Absolute timepoints are stored in this opaque type.
* It is best not to inspect its content directly.
*
* @see sys_timepoint_calc()
* @see sys_timepoint_timeout()
* @see sys_timepoint_expired()
*/
typedef struct { uint64_t tick; } k_timepoint_t;
/**
* @brief Calculate a timepoint value
*
* Returns a timepoint corresponding to the expiration (relative to an
* unlocked "now"!) of a timeout object. When used correctly, this should
* be called once, synchronously with the user passing a new timeout value.
* It should not be used iteratively to adjust a timeout (see
* `sys_timepoint_timeout()` for that purpose).
*
* @param timeout Timeout value relative to current time (may also be
* `K_FOREVER` or `K_NO_WAIT`).
* @retval Timepoint value corresponding to given timeout
*
* @see sys_timepoint_timeout()
* @see sys_timepoint_expired()
*/
k_timepoint_t sys_timepoint_calc(k_timeout_t timeout);
/**
* @brief Remaining time to given timepoint
*
* Returns the timeout interval between current time and provided timepoint.
* If the timepoint is now in the past or if it was created with `K_NO_WAIT`
* then `K_NO_WAIT` is returned. If it was created with `K_FOREVER` then
* `K_FOREVER` is returned.
*
* @param timepoint Timepoint for which a timeout value is wanted.
* @retval Corresponding timeout value.
*
* @see sys_timepoint_calc()
*/
k_timeout_t sys_timepoint_timeout(k_timepoint_t timepoint);
/**
* @brief Provided for backward compatibility.
*
* This is deprecated. Consider `sys_timepoint_calc()` instead.
*
* @see sys_timepoint_calc()
*/
__deprecated
static inline uint64_t sys_clock_timeout_end_calc(k_timeout_t timeout)
{
k_timepoint_t tp = sys_timepoint_calc(timeout);
return tp.tick;
}
/**
* @brief Compare two timepoint values.
*
* This function is used to compare two timepoint values.
*
* @param a Timepoint to compare
* @param b Timepoint to compare against.
* @return zero if both timepoints are the same. Negative value if timepoint @a a is before
* timepoint @a b, positive otherwise.
*/
static inline int sys_timepoint_cmp(k_timepoint_t a, k_timepoint_t b)
{
if (a.tick == b.tick) {
return 0;
}
return a.tick < b.tick ? -1 : 1;
}
#else
/*
* When timers are configured out, timepoints can't relate to anything.
* The best we can do is to preserve whether or not they are derived from
* K_NO_WAIT. Anything else will translate back to K_FOREVER.
*/
typedef struct { bool wait; } k_timepoint_t;
static inline k_timepoint_t sys_timepoint_calc(k_timeout_t timeout)
{
k_timepoint_t timepoint;
timepoint.wait = !K_TIMEOUT_EQ(timeout, Z_TIMEOUT_NO_WAIT);
return timepoint;
}
static inline k_timeout_t sys_timepoint_timeout(k_timepoint_t timepoint)
{
return timepoint.wait ? Z_FOREVER : Z_TIMEOUT_NO_WAIT;
}
static inline int sys_timepoint_cmp(k_timepoint_t a, k_timepoint_t b)
{
if (a.wait == b.wait) {
return 0;
}
return b.wait ? -1 : 1;
}
#endif
/**
* @brief Indicates if timepoint is expired
*
* @param timepoint Timepoint to evaluate
* @retval true if the timepoint is in the past, false otherwise
*
* @see sys_timepoint_calc()
*/
static inline bool sys_timepoint_expired(k_timepoint_t timepoint)
{
return K_TIMEOUT_EQ(sys_timepoint_timeout(timepoint), Z_TIMEOUT_NO_WAIT);
}
/** @} */
#ifdef __cplusplus
}
#endif
#endif /* ZEPHYR_INCLUDE_SYS_CLOCK_H_ */