/*-
 * Copyright (c) 2014 Ian Lepore <ian@freebsd.org>
 * All rights reserved.
 *
 * 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 AUTHOR 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 AUTHOR 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.
 *
 * $FreeBSD: releng/12.0/sys/arm/arm/mpcore_timervar.h 264051 2014-04-02 18:49:50Z ian $
 */

#ifndef	_ARM_MPCORE_TIMERVAR_H_
#define	_ARM_MPCORE_TIMERVAR_H_

/*
 * This value, passed to arm_tmr_change_frequency() any time before the mpcore
 * timer device attaches, informs the driver that the mpcore clock frequency can
 * change on the fly, and thus can't be used as a timecounter.  The hardware can
 * still be used as an eventtimer, as long as each frequency change is
 * communicated to it with calls to arm_tmr_change_frequency().
 */
#define	ARM_TMR_FREQUENCY_VARIES	-1ULL

/*
 * Inform the mpcore timer driver of a new clock frequency.  This can be called
 * both before and after the mpcore timer driver attaches.
 */
void arm_tmr_change_frequency(uint64_t newfreq);

#endif
