/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2018 Rubicon Communications, LLC (Netgate)
 *
 * 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/systm.h>
#include <sys/bus.h>

#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/rman.h>
#include <sys/lock.h>
#include <sys/mutex.h>

#include <machine/bus.h>
#include <machine/resource.h>
#include <machine/intr.h>

#include <dev/clk/clk_fixed.h>
#include <dev/syscon/syscon.h>

#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>

#include "syscon_if.h"

static struct clk_fixed_def ap806_clk_cluster_0 = {
        .clkdef.id = 0,
        .clkdef.name = "ap806-cpu-cluster-0",
        .freq = 0,
};

static struct clk_fixed_def ap806_clk_cluster_1 = {
        .clkdef.id = 1,
        .clkdef.name = "ap806-cpu-cluster-1",
        .freq = 0,
};

static struct clk_fixed_def ap806_clk_fixed = {
        .clkdef.id = 2,
        .clkdef.name = "ap806-fixed",
        .freq = 1200000000,
};

/* Thoses are the only exported clocks AFAICT */

static const char *mss_parents[] = {"ap806-fixed"};
static struct clk_fixed_def ap806_clk_mss = {
        .clkdef.id = 3,
        .clkdef.name = "ap806-mss",
        .clkdef.parent_names = mss_parents,
        .clkdef.parent_cnt = 1,
        .mult = 1,
        .div = 6,
};

static const char *sdio_parents[] = {"ap806-fixed"};
static struct clk_fixed_def ap806_clk_sdio = {
        .clkdef.id = 4,
        .clkdef.name = "ap806-sdio",
        .clkdef.parent_names = sdio_parents,
        .clkdef.parent_cnt = 1,
        .mult = 1,
        .div = 3,
};

struct mv_ap806_clock_softc {
        device_t                dev;
        struct syscon           *syscon;
};

static struct ofw_compat_data compat_data[] = {
        {"marvell,ap806-clock", 1},
        {NULL,                  0}
};

#define RD4(sc, reg)            SYSCON_READ_4((sc)->syscon, (reg))
#define WR4(sc, reg, val)       SYSCON_WRITE_4((sc)->syscon, (reg), (val))

static int
mv_ap806_clock_probe(device_t dev)
{

        if (!ofw_bus_status_okay(dev))
                return (ENXIO);

        if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
                return (ENXIO);

        device_set_desc(dev, "Marvell AP806 Clock Controller");
        return (BUS_PROBE_DEFAULT);
}

static int
mv_ap806_clock_attach(device_t dev)
{
        struct mv_ap806_clock_softc *sc;
        struct clkdom *clkdom;
        uint64_t clock_freq;
        uint32_t reg;

        sc = device_get_softc(dev);
        sc->dev = dev;

        if (SYSCON_GET_HANDLE(sc->dev, &sc->syscon) != 0 ||
            sc->syscon == NULL) {
                device_printf(dev, "cannot get syscon for device\n");
                return (ENXIO);
        }

        reg = RD4(sc, 0x400);
        switch (reg & 0x1f) {
        case 0x0:
        case 0x1:
                clock_freq = 2000000000;
                break;
        case 0x4:
                clock_freq = 1600000000;
                break;
        case 0x6:
                clock_freq = 1800000000;
                break;
        case 0x7:
                clock_freq = 1800000000;
                break;
        case 0xb:
                clock_freq = 1600000000;
                break;
        case 0xd:
                clock_freq = 1600000000;
                break;
        case 0x13:
                clock_freq = 1000000000;
                break;
        case 0x14:
                clock_freq = 1333000000;
                break;
        case 0x17:
                clock_freq = 1333000000;
                break;
        case 0x19:
                clock_freq = 1200000000;
                break;
        case 0x1a:
                clock_freq = 1400000000;
                break;
        case 0x1b:
                clock_freq = 600000000;
                break;
        case 0x1c:
                clock_freq = 800000000;
                break;
        case 0x1d:
                clock_freq = 1000000000;
                break;
        default:
                device_printf(dev, "Cannot guess clock freq with reg %x\n",
                     reg & 0x1f);
                return (ENXIO);
                break;
        };

        ap806_clk_cluster_0.freq = clock_freq;
        ap806_clk_cluster_1.freq = clock_freq;
        clkdom = clkdom_create(dev);

        clknode_fixed_register(clkdom, &ap806_clk_cluster_0);
        clknode_fixed_register(clkdom, &ap806_clk_cluster_1);
        clknode_fixed_register(clkdom, &ap806_clk_fixed);
        clknode_fixed_register(clkdom, &ap806_clk_mss);
        clknode_fixed_register(clkdom, &ap806_clk_sdio);

        clkdom_finit(clkdom);

        if (bootverbose)
                clkdom_dump(clkdom);
        return (0);
}

static int
mv_ap806_clock_detach(device_t dev)
{

        return (EBUSY);
}

static device_method_t mv_ap806_clock_methods[] = {
        /* Device interface */
        DEVMETHOD(device_probe,         mv_ap806_clock_probe),
        DEVMETHOD(device_attach,        mv_ap806_clock_attach),
        DEVMETHOD(device_detach,        mv_ap806_clock_detach),

        DEVMETHOD_END
};

static driver_t mv_ap806_clock_driver = {
        "mv_ap806_clock",
        mv_ap806_clock_methods,
        sizeof(struct mv_ap806_clock_softc),
};

EARLY_DRIVER_MODULE(mv_ap806_clock, simplebus, mv_ap806_clock_driver, 0, 0,
    BUS_PASS_RESOURCE + BUS_PASS_ORDER_LATE);