xref: /freebsd-11-stable/sys/dev/extres/clk/clk_fixed.h

/*-
 * Copyright 2016 Michal Meloun <mmel@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.
 *
 * $FreeBSD$
 */

#ifndef _DEV_EXTRES_CLK_FIXED_H_
#define _DEV_EXTRES_CLK_FIXED_H_

#include <dev/extres/clk/clk.h>

/*
 * A fixed clock can represent several different real-world objects, including
 * an oscillator with a fixed output frequency, a fixed divider (multiplier and
 * divisor must both be > 0), or a phase-fractional divider within a PLL
 * (however the code currently divides first, then multiplies, potentially
 * leading to different roundoff errors than the hardware PLL).
 */

struct clk_fixed_def {
	struct clknode_init_def clkdef;
	uint64_t		freq;
	uint32_t		mult;
	uint32_t		div;
	int			fixed_flags;
};

int clknode_fixed_register(struct clkdom *clkdom, struct clk_fixed_def *clkdef);

#endif /*_DEV_EXTRES_CLK_FIXED_H_*/