nuttx/sched/clock_internal.h
patacongo aca030153f Add support for custom system timer frequency
git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@274 42af7a65-404d-4744-a932-0658087f49c3
2007-06-09 15:49:44 +00:00

118 lines
4.8 KiB
C

/********************************************************************************
* clock_internal.h
*
* Copyright (C) 2007 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name Gregory Nutt nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
********************************************************************************/
#ifndef __CLOCK_INTERNAL_H
#define __CLOCK_INTERNAL_H
/********************************************************************************
* Included Files
********************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <nuttx/compiler.h>
/********************************************************************************
* Definitions
********************************************************************************/
/* Timing constants */
#define NSEC_PER_SEC 1000000000
#define USEC_PER_SEC 1000000
#define MSEC_PER_SEC 1000
#define NSEC_PER_MSEC 1000000
#define USEC_PER_MSEC 1000
#define NSEC_PER_USEC 1000
/* The interrupt interval of the system timer is given by MSEC_PER_TICK. This
* is the expected number of milliseconds between calls from the processor-
* specific logic to sched_process_timer(). The default value of MSEC_PER_TICK
* is 10 milliseconds (100KHz). However, this default setting can be overridden
* by defining the interval in milliseconds as CONFIG_MSEC_PER_TICK in the board
* configuration file.
*/
#ifdef CONFIG_MSEC_PER_TICK
# define MSEC_PER_TICK (CONFIG_MSEC_PER_TICK)
#else
# define MSEC_PER_TICK (10)
#endif
#define USEC_PER_TICK (MSEC_PER_TICK * USEC_PER_MSEC)
#define NSEC_PER_TICK (MSEC_PER_TICK * NSEC_PER_MSEC)
#define TICK_PER_SEC (MSEC_PER_SEC / MSEC_PER_TICK)
#define MSEC2TICK(msec) (((msec)+(MSEC_PER_TICK/2))/MSEC_PER_TICK)
#define USEC2TICK(usec) (((usec)+(USEC_PER_TICK/2))/USEC_PER_TICK)
#define JD_OF_EPOCH 2440588 /* Julian Date of noon, J1970 */
#ifdef CONFIG_JULIAN_TIME
# define GREG_DUTC -141427 /* Default is October 15, 1582 */
# define GREG_YEAR 1582
# define GREG_MONTH 10
# define GREG_DAY 15
#endif /* CONFIG_JULIAN_TIME */
/********************************************************************************
* Public Type Definitions
********************************************************************************/
/********************************************************************************
* Global Variables
********************************************************************************/
extern volatile uint32 g_system_timer;
extern struct timespec g_basetime;
extern uint32 g_tickbias;
/********************************************************************************
* Public Function Prototypes
********************************************************************************/
extern void weak_function clock_initialize(void);
extern void weak_function clock_timer(void);
extern time_t clock_calendar2utc(int year, int month, int day);
extern int clock_abstime2ticks(clockid_t clockid, const struct timespec *abstime,
int *ticks);
extern int clock_time2ticks(const struct timespec *reltime, int *ticks);
extern int clock_ticks2time(int ticks, struct timespec *reltime);
#endif /* __CLOCK_INTERNAL_H */