zephyr/include/sys_clock.h

224 lines
6.0 KiB
C

/*
* Copyright (c) 2014-2015 Wind River Systems, Inc.
*
* SPDX-License-Identifier: Apache-2.0
*/
/**
* @file
* @brief Variables needed 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 <sys/util.h>
#include <sys/dlist.h>
#include <toolchain.h>
#include <zephyr/types.h>
#include <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)
#ifndef CONFIG_LEGACY_TIMEOUT_API
/**
* @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)
#define Z_TIMEOUT_NO_WAIT ((k_timeout_t) {})
#define Z_TIMEOUT_TICKS(t) ((k_timeout_t) { .ticks = (t) })
#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)))
#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)))
#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 returend 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))
#else
/* Legacy timeout API */
typedef int32_t k_timeout_t;
#define K_TIMEOUT_EQ(a, b) ((a) == (b))
#define Z_TIMEOUT_NO_WAIT 0
#define Z_TIMEOUT_TICKS(t) k_ticks_to_ms_ceil32(t)
#define Z_FOREVER K_TICKS_FOREVER
#define Z_TIMEOUT_MS(t) (t)
#define Z_TIMEOUT_US(t) ((999 + (t)) / 1000)
#define Z_TIMEOUT_NS(t) ((999999 + (t)) / 1000000)
#define Z_TIMEOUT_CYC(t) k_cyc_to_ms_ceil32(MAX((t), 0))
#endif
/** @} */
#ifdef CONFIG_TICKLESS_KERNEL
extern int _sys_clock_always_on;
extern void z_enable_sys_clock(void);
#endif
#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
/* number of nsec per usec */
#define NSEC_PER_USEC 1000U
/* number of microseconds per millisecond */
#define USEC_PER_MSEC 1000U
/* number of milliseconds per second */
#define MSEC_PER_SEC 1000U
/* 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))
/* 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.
*/
#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
#define z_ms_to_ticks(t) \
((int32_t)k_ms_to_ticks_ceil32((uint32_t)(t)))
/* added tick needed to account for tick in progress */
#define _TICK_ALIGN 1
/*
* 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)
/**
* @defgroup clock_apis Kernel Clock APIs
* @ingroup kernel_apis
* @{
*/
/**
* @} end defgroup clock_apis
*/
/**
*
* @brief Return the lower part of the current system tick count
*
* @return the current system tick count
*
*/
uint32_t z_tick_get_32(void);
/**
*
* @brief Return the current system tick count
*
* @return the current system tick count
*
*/
int64_t z_tick_get(void);
#ifndef CONFIG_SYS_CLOCK_EXISTS
#define z_tick_get() (0)
#define z_tick_get_32() (0)
#endif
uint64_t z_timeout_end_calc(k_timeout_t timeout);
#ifdef __cplusplus
}
#endif
#endif /* ZEPHYR_INCLUDE_SYS_CLOCK_H_ */