root/sys/arm/freescale/vybrid/vf_tcon.c
/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2014 Ruslan Bukin <br@bsdpad.com>
 * 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.
 */

/*
 * Vybrid Family Timing Controller (TCON)
 * Chapter 58, Vybrid Reference Manual, Rev. 5, 07/2013
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/malloc.h>
#include <sys/rman.h>
#include <sys/timeet.h>
#include <sys/timetc.h>
#include <sys/watchdog.h>

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

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

#include <arm/freescale/vybrid/vf_common.h>

#define TCON0_CTRL1     0x00
#define TCON_BYPASS     (1 << 29)

struct tcon_softc {
        struct resource         *res[1];
        bus_space_tag_t         bst;
        bus_space_handle_t      bsh;
};

struct tcon_softc *tcon_sc;

static struct resource_spec tcon_spec[] = {
        { SYS_RES_MEMORY,       0,      RF_ACTIVE },
        { -1, 0 }
};

uint32_t
tcon_bypass(void)
{

        if (tcon_sc == NULL)
                return (1);

        WRITE4(tcon_sc, TCON0_CTRL1, TCON_BYPASS);

        return (0);
}

static int
tcon_probe(device_t dev)
{

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

        if (!ofw_bus_is_compatible(dev, "fsl,mvf600-tcon"))
                return (ENXIO);

        device_set_desc(dev, "Vybrid Family Timing Controller (TCON)");
        return (BUS_PROBE_DEFAULT);
}

static int
tcon_attach(device_t dev)
{
        struct tcon_softc *sc;

        sc = device_get_softc(dev);

        if (bus_alloc_resources(dev, tcon_spec, sc->res)) {
                device_printf(dev, "could not allocate resources\n");
                return (ENXIO);
        }

        /* Memory interface */
        sc->bst = rman_get_bustag(sc->res[0]);
        sc->bsh = rman_get_bushandle(sc->res[0]);

        tcon_sc = sc;

        return (0);
}

static device_method_t tcon_methods[] = {
        DEVMETHOD(device_probe,         tcon_probe),
        DEVMETHOD(device_attach,        tcon_attach),
        { 0, 0 }
};

static driver_t tcon_driver = {
        "tcon",
        tcon_methods,
        sizeof(struct tcon_softc),
};

DRIVER_MODULE(tcon, simplebus, tcon_driver, 0, 0);