103 lines
3.0 KiB
C
103 lines
3.0 KiB
C
/* Variables needed needed for system clock */
|
|
|
|
/*
|
|
* Copyright (c) 2014-2015 Wind River Systems, Inc.
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*/
|
|
|
|
/*
|
|
* DESCRIPTION
|
|
*
|
|
* Declare variables used by both system timer device driver and kernel
|
|
* components that use timer functionality.
|
|
*/
|
|
|
|
#ifndef _SYS_CLOCK__H_
|
|
#define _SYS_CLOCK__H_
|
|
|
|
#ifndef _ASMLANGUAGE
|
|
#include <stdint.h>
|
|
|
|
#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
|
|
|
|
#define sys_clock_ticks_per_sec CONFIG_SYS_CLOCK_TICKS_PER_SEC
|
|
|
|
#if defined(CONFIG_TIMER_READS_ITS_FREQUENCY_AT_RUNTIME)
|
|
extern int sys_clock_hw_cycles_per_sec;
|
|
#else
|
|
#define sys_clock_hw_cycles_per_sec CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC
|
|
#endif
|
|
|
|
/*
|
|
* sys_clock_us_per_tick global variable represents a number
|
|
* of microseconds in one OS timer tick
|
|
*/
|
|
extern int sys_clock_us_per_tick;
|
|
|
|
/*
|
|
* sys_clock_hw_cycles_per_tick global variable represents a number
|
|
* of platform clock ticks in one OS timer tick.
|
|
* sys_clock_hw_cycles_per_tick often represents a value of divider
|
|
* of the board clock frequency
|
|
*/
|
|
extern int sys_clock_hw_cycles_per_tick;
|
|
|
|
/* number of nsec per usec */
|
|
#define NSEC_PER_USEC 1000
|
|
|
|
/* number of microseconds per millisecond */
|
|
#define USEC_PER_MSEC 1000
|
|
|
|
/* number of milliseconds per second */
|
|
#define MSEC_PER_SEC 1000
|
|
|
|
/* 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))
|
|
|
|
|
|
/* SYS_CLOCK_HW_CYCLES_TO_NS64 converts CPU clock cycles to nanoseconds */
|
|
#define SYS_CLOCK_HW_CYCLES_TO_NS64(X) \
|
|
(((uint64_t)(X) * sys_clock_us_per_tick * NSEC_PER_USEC) / \
|
|
sys_clock_hw_cycles_per_tick)
|
|
|
|
/*
|
|
* 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)(SYS_CLOCK_HW_CYCLES_TO_NS64(X) / NCYCLES)
|
|
|
|
#define SYS_CLOCK_HW_CYCLES_TO_NS(X) (uint32_t)(SYS_CLOCK_HW_CYCLES_TO_NS64(X))
|
|
|
|
extern int64_t _sys_clock_tick_count;
|
|
extern struct nano_timer *_nano_timer_list;
|
|
|
|
/*
|
|
* Number of ticks for x seconds. NOTE: With MSEC(), since it does an integer
|
|
* division, x must be greater or equal to 1000/sys_clock_ticks_per_sec to get
|
|
* a non-zero value.
|
|
*/
|
|
#define SECONDS(x) ((x) * sys_clock_ticks_per_sec)
|
|
#define MSEC(x) (SECONDS(x) / 1000)
|
|
|
|
#endif /* !_ASMLANGUAGE */
|
|
|
|
#endif /* _SYS_CLOCK__H_ */
|