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/*
* Copyright (c) 1996-1999 University of Utah and the Flux Group.
* All rights reserved.
*
* This file is part of the Flux OSKit. The OSKit is free software, also known
* as "open source;" you can redistribute it and/or modify it under the terms
* of the GNU General Public License (GPL), version 2, as published by the Free
* Software Foundation (FSF). To explore alternate licensing terms, contact
* the University of Utah at csl-dist@cs.utah.edu or +1-801-585-3271.
*
* The OSKit is distributed in the hope that it will be useful, but WITHOUT ANY
* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the GPL for more details. You should have
* received a copy of the GPL along with the OSKit; see the file COPYING. If
* not, write to the FSF, 59 Temple Place #330, Boston, MA 02111-1307, USA.
*/
/*
* Timer interrupt support.
* This contains helper functions for the fdev_timer interface.
* This is in a separate file for the convenience of the Unix code
* so it only has to override half the fdev_timer support.
*/
#include <oskit/dev/dev.h>
#include <oskit/debug.h>
#include <oskit/arm32/pio.h>
#include <oskit/arm32/proc_reg.h>
#include <oskit/arm32/shark/pit.h>
static void(*handler)();
int
osenv_timer_pit_init(int freq, void (*timer_intr)())
{
/*
* Initialize timer to interrupt at TIMER_FREQ Hz.
*/
pit_init(freq);
/*
* Install interrupt handler.
*/
if (osenv_irq_alloc(0, timer_intr, 0, 0))
osenv_panic(__FUNCTION__": couldn't install intr handler");
handler = timer_intr;
return freq;
}
void
osenv_timer_pit_shutdown()
{
osenv_irq_free(0, handler, 0);
}
int
osenv_timer_pit_read()
{
int enb = osenv_intr_enabled();
int value;
osenv_intr_disable();
value = pit_read(0);
if (enb)
osenv_intr_enable();
return value;
}
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