/*-
 * Copyright (c) 2020 Oskar Holmlund <oskar.holmlund@ohdata.se>
 *
 * 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.
 */
/*
 * Power management - simple driver to handle reset and give access to
 * memory space region for other drivers through prcm driver.
 * Documentation/devicetree/binding/arm/omap/prm-inst.txt
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/module.h>

#include <dev/fdt/simplebus.h>

#include <dev/ofw/ofw_bus_subr.h>

#include <arm/ti/ti_prcm.h>
#include <arm/ti/ti_prm.h>

#if 0
#define DPRINTF(dev, msg...) device_printf(dev, msg)
#else
#define DPRINTF(dev, msg...)
#endif

/* relative to prcm address range */
#define TI_PRM_PER_RSTCTRL      0xC00

struct ti_prm_softc {
        device_t                dev;
        uint8_t                 type;
        bool                    has_reset;
};

/* Device */
#define TI_OMAP_PRM_INST        10

#define TI_AM3_PRM_INST         5
#define TI_AM4_PRM_INST         4
#define TI_OMAP4_PRM_INST       3
#define TI_OMAP5_PRM_INST       2
#define TI_DRA7_PRM_INST        1
#define TI_END                  0

static struct ofw_compat_data compat_data[] = {
        { "ti,am3-prm-inst",    TI_AM3_PRM_INST },
        { "ti,am4-prm-inst",    TI_AM4_PRM_INST },
        { "ti,omap4-prm-inst",  TI_OMAP4_PRM_INST },
        { "ti,omap5-prm-inst",  TI_OMAP5_PRM_INST },
        { "ti,dra7-prm-inst",   TI_DRA7_PRM_INST },
        { NULL,         TI_END }
};

static struct ofw_compat_data required_data[] = {
        { "ti,omap-prm-inst", TI_OMAP_PRM_INST },
        { NULL, TI_END }
};

/* device interface */
static int
ti_prm_probe(device_t dev)
{
        if (!ofw_bus_status_okay(dev))
                return (ENXIO);

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

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

        device_set_desc(dev, "TI OMAP Power Management");
        return(BUS_PROBE_DEFAULT);
}

static int
ti_prm_attach(device_t dev)
{
        struct ti_prm_softc *sc;
        phandle_t node;

        sc = device_get_softc(dev);
        sc->dev = dev;
        sc->type = ofw_bus_search_compatible(dev, compat_data)->ocd_data;

        node = ofw_bus_get_node(sc->dev);

        if (OF_hasprop(node, "#reset-cells")) {
                sc->has_reset = true;
        } else
                sc->has_reset = false;

        /* Make device visible for other drivers */
        OF_device_register_xref(OF_xref_from_node(node), sc->dev);

        return (0);
}

static int
ti_prm_detach(device_t dev) {
        return (EBUSY);
}

int
ti_prm_reset(device_t dev)
{
        struct ti_prm_softc *sc;
        int err;

        sc = device_get_softc(dev);
        if (sc->has_reset == false)
                return 1;

        err = ti_prm_modify_4(dev, TI_PRM_PER_RSTCTRL, 0x2, 0x00);
        return (err);
}

int
ti_prm_write_4(device_t dev, bus_addr_t addr, uint32_t val)
{
        device_t parent;

        parent = device_get_parent(dev);
        DPRINTF(dev, "offset=%lx write %x\n", addr, val);
        ti_prcm_device_lock(parent);
        ti_prcm_write_4(parent, addr, val);
        ti_prcm_device_unlock(parent);
        return (0);
}

int
ti_prm_read_4(device_t dev, bus_addr_t addr, uint32_t *val)
{
        device_t parent;

        parent = device_get_parent(dev);

        ti_prcm_device_lock(parent);
        ti_prcm_read_4(parent, addr, val);
        ti_prcm_device_unlock(parent);
        DPRINTF(dev, "offset=%lx Read %x\n", addr, *val);
        return (0);
}

int
ti_prm_modify_4(device_t dev, bus_addr_t addr, uint32_t clr, uint32_t set)
{
        device_t parent;

        parent = device_get_parent(dev);

        ti_prcm_device_lock(parent);
        ti_prcm_modify_4(parent, addr, clr, set);
        ti_prcm_device_unlock(parent);
        DPRINTF(dev, "offset=%lx (clr %x set %x)\n", addr, clr, set);

        return (0);
}

static device_method_t ti_prm_methods[] = {
        DEVMETHOD(device_probe,         ti_prm_probe),
        DEVMETHOD(device_attach,        ti_prm_attach),
        DEVMETHOD(device_detach,        ti_prm_detach),

        DEVMETHOD_END
};

DEFINE_CLASS_1(ti_prm, ti_prm_driver, ti_prm_methods,
    sizeof(struct ti_prm_softc), simplebus_driver);

EARLY_DRIVER_MODULE(ti_prm, simplebus, ti_prm_driver, 0, 0,
    BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
MODULE_VERSION(ti_prm, 1);
MODULE_DEPEND(ti_prm, ti_sysc, 1, 1, 1);