clk_mux.c

/*-
 * Copyright 2016 Michal Meloun <[email protected]>
 * 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.
 */

#include <sys/param.h>
#include <sys/conf.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/systm.h>

#include <machine/bus.h>

#include <dev/clk/clk_mux.h>

#include "clkdev_if.h"

#define	WR4(_clk, off, val)						\
	CLKDEV_WRITE_4(clknode_get_device(_clk), off, val)
#define	RD4(_clk, off, val)						\
	CLKDEV_READ_4(clknode_get_device(_clk), off, val)
#define	MD4(_clk, off, clr, set )					\
	CLKDEV_MODIFY_4(clknode_get_device(_clk), off, clr, set)
#define	DEVICE_LOCK(_clk)							\
	CLKDEV_DEVICE_LOCK(clknode_get_device(_clk))
#define	DEVICE_UNLOCK(_clk)						\
	CLKDEV_DEVICE_UNLOCK(clknode_get_device(_clk))

static int clknode_mux_init(struct clknode *clk, device_t dev);
static int clknode_mux_set_mux(struct clknode *clk, int idx);

struct clknode_mux_sc {
	uint32_t	offset;
	uint32_t	shift;
	uint32_t	mask;
	int		mux_flags;
};

static clknode_method_t clknode_mux_methods[] = {
	/* Device interface */
	CLKNODEMETHOD(clknode_init, 	clknode_mux_init),
	CLKNODEMETHOD(clknode_set_mux, 	clknode_mux_set_mux),
	CLKNODEMETHOD_END
};
DEFINE_CLASS_1(clknode_mux, clknode_mux_class, clknode_mux_methods,
   sizeof(struct clknode_mux_sc), clknode_class);


static int
clknode_mux_init(struct clknode *clk, device_t dev)
{
	uint32_t reg;
	struct clknode_mux_sc *sc;
	int rv;

	sc = clknode_get_softc(clk);

	DEVICE_LOCK(clk);
	rv = RD4(clk, sc->offset, &reg);
	DEVICE_UNLOCK(clk);
	if (rv != 0) {
		return (rv);
	}
	reg = (reg >> sc->shift) & sc->mask;
	clknode_init_parent_idx(clk, reg);
	return(0);
}

static int
clknode_mux_set_mux(struct clknode *clk, int idx)
{
	uint32_t reg;
	struct clknode_mux_sc *sc;
	int rv;

	sc = clknode_get_softc(clk);

	DEVICE_LOCK(clk);
	rv = MD4(clk, sc->offset, sc->mask << sc->shift,
	    (idx & sc->mask) << sc->shift);
	if (rv != 0) {
		DEVICE_UNLOCK(clk);
		return (rv);
	}
	RD4(clk, sc->offset, &reg);
	DEVICE_UNLOCK(clk);

	return(0);
}

int
clknode_mux_register(struct clkdom *clkdom, struct clk_mux_def *clkdef)
{
	struct clknode *clk;
	struct clknode_mux_sc *sc;

	clk = clknode_create(clkdom, &clknode_mux_class, &clkdef->clkdef);
	if (clk == NULL)
		return (1);

	sc = clknode_get_softc(clk);
	sc->offset = clkdef->offset;
	sc->shift = clkdef->shift;
	sc->mask =  (1 << clkdef->width) - 1;
	sc->mux_flags = clkdef->mux_flags;

	clknode_register(clkdom, clk);
	return (0);
}