/*
* Copyright (C) 2005 Jakub Jermar
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - 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.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*/
/** Interval Timer driver. */
#include <arch/drivers/it.h>
#include <arch/interrupt.h>
#include <arch/register.h>
#include <arch/asm.h>
#include <arch/barrier.h>
#include <time/clock.h>
/** Initialize Interval Timer. */
void it_init(void)
{
cr_itv_t itv;
/* initialize Interval Timer external interrupt vector */
itv.value = itv_read();
itv.vector = INTERRUPT_TIMER;
itv.m = 0;
itv_write(itv.value);
/* set Interval Timer Counter to zero */
itc_write(0);
/* generate first Interval Timer interrupt in IT_DELTA ticks */
itm_write(IT_DELTA);
/* propagate changes */
srlz_d();
}
/** Process Interval Timer interrupt. */
void it_interrupt(void)
{
eoi_write(EOI);
itm_write(itc_read() + IT_DELTA); /* program next interruption */
srlz_d(); /* propagate changes */
}