/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2023 Beckhoff Automation GmbH & Co. KG
 *
 * 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/cdefs.h>

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

#include <dev/clk/clk.h>

#include <dev/clk/xilinx/zynqmp_clk_div.h>

#include "clkdev_if.h"
#include "zynqmp_firmware_if.h"

#define DIV_ROUND_CLOSEST(n, d) (((n) + (d) / 2) / (d))

struct zynqmp_clk_div_softc {
        device_t                        firmware;
        enum zynqmp_clk_div_type        type;
        uint32_t                        id;
};

static int
zynqmp_clk_div_init(struct clknode *clk, device_t dev)
{

        clknode_init_parent_idx(clk, 0);
        return (0);
}

static int
zynqmp_clk_div_recalc(struct clknode *clk, uint64_t *freq)
{
        struct zynqmp_clk_div_softc *sc;
        uint32_t div;
        int rv;

        sc = clknode_get_softc(clk);
        rv = ZYNQMP_FIRMWARE_CLOCK_GETDIVIDER(sc->firmware, sc->id, &div);
        if (rv != 0) {
                printf("%s: Error while getting divider for %s\n",
                    __func__,
                    clknode_get_name(clk));
                return (EINVAL);
        }

        if (sc->type == CLK_DIV_TYPE_DIV0)
                div &= 0xFFFF;
        else
                div = div >> 16;
        *freq = howmany((unsigned long long)*freq, div + 1);
        return (0);
}

static int
zynqmp_clk_div_set_freq(struct clknode *clk, uint64_t fparent, uint64_t *fout,
    int flags, int *stop)
{
        struct zynqmp_clk_div_softc *sc;
        uint32_t div;
        int rv;

        sc = clknode_get_softc(clk);

        div = DIV_ROUND_CLOSEST(fparent, *fout);
        if (sc->type == CLK_DIV_TYPE_DIV0) {
                div &= 0xFFFF;
                div |= 0xFFFF << 16;
        } else {
                div <<= 16;
                div |= 0xFFFF;
        }

        rv = ZYNQMP_FIRMWARE_CLOCK_SETDIVIDER(sc->firmware, sc->id, div);
        if (rv != 0) {
                printf("%s: Error while setting divider for %s\n",
                    __func__,
                    clknode_get_name(clk));
                return (EINVAL);
        }

        return (rv);
}

static clknode_method_t zynqmp_clk_div_clknode_methods[] = {
        /* Device interface */
        CLKNODEMETHOD(clknode_init,             zynqmp_clk_div_init),
        CLKNODEMETHOD(clknode_recalc_freq,      zynqmp_clk_div_recalc),
        CLKNODEMETHOD(clknode_set_freq,         zynqmp_clk_div_set_freq),
        CLKNODEMETHOD_END
};

DEFINE_CLASS_1(zynqmp_clk_div_clknode, zynqmp_clk_div_clknode_class,
    zynqmp_clk_div_clknode_methods, sizeof(struct zynqmp_clk_div_softc), clknode_class);

int
zynqmp_clk_div_register(struct clkdom *clkdom, device_t fw, struct clknode_init_def *clkdef, enum zynqmp_clk_div_type type)
{
        struct clknode *clk;
        struct zynqmp_clk_div_softc *sc;
        uint32_t fw_clk_id;

        fw_clk_id = clkdef->id - 1;
        clkdef->id = 0;
        clk = clknode_create(clkdom, &zynqmp_clk_div_clknode_class, clkdef);
        if (clk == NULL)
                return (1);
        sc = clknode_get_softc(clk);
        sc->id = fw_clk_id;
        sc->firmware = fw;
        sc->type = type;
        clknode_register(clkdom, clk);
        return (0);
}