* arch/arm/src/arm_m/systick.h
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you 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.
*
****************************************************************************/
#ifndef __ARCH_ARM_SRC_ARM_M_SYSTICK_H
#define __ARCH_ARM_SRC_ARM_M_SYSTICK_H
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <nuttx/timers/timer.h>
* Public Function Prototypes
****************************************************************************/
#ifdef __cplusplus
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif
* Name: systick_initialize
*
* Description:
* This function initialize SYSTICK hardware module which is part of NVIC
* and return an instance of a "lower half" timer interface.
*
* Input parameters:
* coreclk - false if SYSTICK working clock come from the external
* reference clock, otherwise true.
* freq - The clock frequency in Hz. If freq is zero, calculate the value
* from NVIC_SYSTICK_CALIB register.
* minor - The timer driver minor number, skip the registration if minor
* < 0.
*
* Returned Value:
* On success, a non-NULL timer_lowerhalf_s is returned to the caller.
* In the event of any failure, a NULL value is returned.
*
****************************************************************************/
#ifdef CONFIG_ARM_SYSTICK
struct timer_lowerhalf_s *systick_initialize(bool coreclk, unsigned int freq,
int minor);
#else
# define systick_initialize(coreclk, freq, minor) NULL
#endif
#undef EXTERN
#ifdef __cplusplus
}
#endif
#endif