/* $NetBSD: rk_cru_mux.c,v 1.2 2018/06/30 17:54:07 jmcneill Exp $ */

/*-
 * Copyright (c) 2018 Jared McNeill <jmcneill@invisible.ca>
 * 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 ``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.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: rk_cru_mux.c,v 1.2 2018/06/30 17:54:07 jmcneill Exp $");

#include <sys/param.h>
#include <sys/bus.h>

#include <dev/clk/clk_backend.h>

#include <arm/rockchip/rk_cru.h>

const char *
rk_cru_mux_get_parent(struct rk_cru_softc *sc,
    struct rk_cru_clk *clk)
{
        struct rk_cru_mux *mux = &clk->u.mux;
        const bool mux_grf = (mux->flags & RK_MUX_GRF) != 0;
        uint32_t val;

        KASSERT(clk->type == RK_CRU_MUX);

        if (mux_grf) {
                if (!HAS_GRF(sc))
                        return NULL;
                syscon_lock(sc->sc_grf);
                val = syscon_read_4(sc->sc_grf, mux->reg);
                syscon_unlock(sc->sc_grf);
        } else {
                val = CRU_READ(sc, mux->reg);
        }
        const u_int index = __SHIFTOUT(val, mux->mask);

        return mux->parents[index];
}

int
rk_cru_mux_set_parent(struct rk_cru_softc *sc,
    struct rk_cru_clk *clk, const char *parent)
{
        struct rk_cru_mux *mux = &clk->u.mux;
        const bool mux_grf = (mux->flags & RK_MUX_GRF) != 0;

        KASSERT(clk->type == RK_CRU_MUX);

        if (mux_grf && !HAS_GRF(sc))
                return ENXIO;

        for (u_int index = 0; index < mux->nparents; index++) {
                if (strcmp(mux->parents[index], parent) == 0) {
                        const uint32_t write_mask = mux->mask << 16;
                        const uint32_t write_val = __SHIFTIN(index, mux->mask);

                        if (mux_grf) {
                                syscon_lock(sc->sc_grf);
                                syscon_write_4(sc->sc_grf, mux->reg, write_mask | write_val);
                                syscon_unlock(sc->sc_grf);
                        } else
                                CRU_WRITE(sc, mux->reg, write_mask | write_val);

                        return 0;
                }
        }

        return EINVAL;
}