/*-
 * 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 Port control and interrupts (PORT)
 * Chapter 6, 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_port.h>
#include <arm/freescale/vybrid/vf_common.h>

/* Pin Control Register */
#define PORT_PCR(n)             (0x1000 * (n >> 5) + 0x4 * (n % 32))
#define  PCR_IRQC_S     16
#define  PCR_IRQC_M     0xF
#define  PCR_DMA_RE     0x1
#define  PCR_DMA_FE     0x2
#define  PCR_DMA_EE     0x3
#define  PCR_INT_LZ     0x8
#define  PCR_INT_RE     0x9
#define  PCR_INT_FE     0xA
#define  PCR_INT_EE     0xB
#define  PCR_INT_LO     0xC
#define  PCR_ISF        (1 << 24)
#define PORT0_ISFR      0xA0    /* Interrupt Status Flag Register */
#define PORT0_DFER      0xC0    /* Digital Filter Enable Register */
#define PORT0_DFCR      0xC4    /* Digital Filter Clock Register */
#define PORT0_DFWR      0xC8    /* Digital Filter Width Register */

struct port_event {
        uint32_t        enabled;
        uint32_t        mux_num;
        uint32_t        mux_src;
        uint32_t        mux_chn;
        void            (*ih) (void *);
        void            *ih_user;
        enum ev_type    pevt;
};

static struct port_event event_map[NGPIO];

struct port_softc {
        struct resource         *res[6];
        bus_space_tag_t         bst;
        bus_space_handle_t      bsh;
        void                    *gpio_ih[NGPIO];
};

struct port_softc *port_sc;

static struct resource_spec port_spec[] = {
        { SYS_RES_MEMORY,       0,      RF_ACTIVE },
        { SYS_RES_IRQ,          0,      RF_ACTIVE },
        { SYS_RES_IRQ,          1,      RF_ACTIVE },
        { SYS_RES_IRQ,          2,      RF_ACTIVE },
        { SYS_RES_IRQ,          3,      RF_ACTIVE },
        { SYS_RES_IRQ,          4,      RF_ACTIVE },
        { -1, 0 }
};

static int
port_intr(void *arg)
{
        struct port_event *pev;
        struct port_softc *sc;
        int reg;
        int i;

        sc = arg;

        for (i = 0; i < NGPIO; i++) {
                reg = READ4(sc, PORT_PCR(i));
                if (reg & PCR_ISF) {
                        /* Clear interrupt */
                        WRITE4(sc, PORT_PCR(i), reg);

                        /* Handle event */
                        pev = &event_map[i];
                        if (pev->enabled == 1) {
                                if (pev->ih != NULL) {
                                        pev->ih(pev->ih_user);
                                }
                        }
                }
        }

        return (FILTER_HANDLED);
}

int
port_setup(int pnum, enum ev_type pevt, void (*ih)(void *), void *ih_user)
{
        struct port_event *pev;
        struct port_softc *sc;
        int reg;
        int val;

        sc = port_sc;

        switch (pevt) {
        case DMA_RISING_EDGE:
                val = PCR_DMA_RE;
                break;
        case DMA_FALLING_EDGE:
                val = PCR_DMA_FE;
                break;
        case DMA_EITHER_EDGE:
                val = PCR_DMA_EE;
                break;
        case INT_LOGIC_ZERO:
                val = PCR_INT_LZ;
                break;
        case INT_RISING_EDGE:
                val = PCR_INT_RE;
                break;
        case INT_FALLING_EDGE:
                val = PCR_INT_FE;
                break;
        case INT_EITHER_EDGE:
                val = PCR_INT_EE;
                break;
        case INT_LOGIC_ONE:
                val = PCR_INT_LO;
                break;
        default:
                return (-1);
        }

        reg = READ4(sc, PORT_PCR(pnum));
        reg &= ~(PCR_IRQC_M << PCR_IRQC_S);
        reg |= (val << PCR_IRQC_S);
        WRITE4(sc, PORT_PCR(pnum), reg);

        pev = &event_map[pnum];
        pev->ih = ih;
        pev->ih_user = ih_user;
        pev->pevt = pevt;
        pev->enabled = 1;

        return (0);
}

static int
port_probe(device_t dev)
{

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

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

        device_set_desc(dev, "Vybrid Family Port control and interrupts");
        return (BUS_PROBE_DEFAULT);
}

static int
port_attach(device_t dev)
{
        struct port_softc *sc;
        int irq;

        sc = device_get_softc(dev);

        if (bus_alloc_resources(dev, port_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]);

        port_sc = sc;

        for (irq = 0; irq < NPORTS; irq ++) {
                if ((bus_setup_intr(dev, sc->res[1 + irq], INTR_TYPE_MISC,
                    port_intr, NULL, sc, &sc->gpio_ih[irq]))) {
                        device_printf(dev,
                            "ERROR: Unable to register interrupt handler\n");
                        return (ENXIO);
                }
        }

        return (0);
}

static device_method_t port_methods[] = {
        DEVMETHOD(device_probe,         port_probe),
        DEVMETHOD(device_attach,        port_attach),
        { 0, 0 }
};

static driver_t port_driver = {
        "port",
        port_methods,
        sizeof(struct port_softc),
};

DRIVER_MODULE(port, simplebus, port_driver, 0, 0);