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/* SPDX-License-Identifier: BSD-2-Clause */
/*
* This file provides a template for the clock device driver initialization.
*
* If possible, please use the dev/clock/clockimpl.h method for instantiating
* a clock driver.
*/
/*
* COPYRIGHT (c) 1989-2014.
* On-Line Applications Research Corporation (OAR).
*
* 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.
*
* 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.
*/
#include <stdlib.h>
#include <rtems.h>
#include <bsp.h>
void Clock_exit( void );
rtems_isr Clock_isr( rtems_vector_number vector );
/*
* The interrupt vector number associated with the clock tick device
* driver.
*/
#define CLOCK_VECTOR 4
/*
* Clock_driver_ticks is a monotonically increasing counter of the
* number of clock ticks since the driver was initialized.
*/
volatile uint32_t Clock_driver_ticks;
/*
* Clock_isrs is the number of clock ISRs until the next invocation of
* the RTEMS clock tick routine. The clock tick device driver
* gets an interrupt once a millisecond and counts down until the
* length of time between the user configured microseconds per tick
* has passed.
*/
uint32_t Clock_isrs; /* ISRs until next tick */
/*
* The previous ISR on this clock tick interrupt vector.
*/
rtems_isr_entry Old_ticker;
static void Clock_exit( void );
/*
* Isr Handler
*/
static rtems_isr Clock_isr(
rtems_vector_number vector
)
{
/*
* bump the number of clock driver ticks since initialization
*
* determine if it is time to announce the passing of tick as configured
* to RTEMS through the rtems_clock_tick directive
*
* perform any timer dependent tasks
*/
}
/*
* Install_clock
*
* Install a clock tick handler and reprograms the chip. This
* is used to initially establish the clock tick.
*/
void Install_clock(
rtems_isr_entry clock_isr
)
{
/*
* Initialize the clock tick device driver variables
*/
Clock_driver_ticks = 0;
Clock_isrs = rtems_configuration_get_microseconds_per_tick() / 1000;
Old_ticker = (rtems_isr_entry) set_vector( clock_isr, CLOCK_VECTOR, 1 );
/*
* Hardware specific initialize goes here
*/
/* XXX */
/*
* Schedule the clock cleanup routine to execute if the application exits.
*/
atexit( Clock_exit );
}
/*
* Clean up before the application exits
*/
void Clock_exit( void )
{
/* XXX: turn off the timer interrupts */
/* XXX: If necessary, restore the old vector */
}
void _Clock_Initialize( void )
{
Install_clock( Clock_isr );
}
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