/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2013 Luiz Otavio O Souza.
 * Copyright (c) 2011-2012 Stefan Bethke.
 * Copyright (c) 2012 Adrian Chadd.
 * 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.
 */

#include <sys/param.h>
#include <sys/bus.h>
#include <sys/errno.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/sysctl.h>
#include <sys/systm.h>

#include <net/if.h>
#include <net/if_var.h>
#include <net/ethernet.h>
#include <net/if_media.h>
#include <net/if_types.h>

#include <machine/bus.h>
#include <dev/mii/mii.h>
#include <dev/mii/miivar.h>
#include <dev/mdio/mdio.h>

#include <dev/etherswitch/etherswitch.h>

#include "mdio_if.h"
#include "miibus_if.h"
#include "etherswitch_if.h"

MALLOC_DECLARE(M_UKSWITCH);
MALLOC_DEFINE(M_UKSWITCH, "ukswitch", "ukswitch data structures");

struct ukswitch_softc {
        struct mtx      sc_mtx;         /* serialize access to softc */
        device_t        sc_dev;
        int             media;          /* cpu port media */
        int             cpuport;        /* which PHY is connected to the CPU */
        int             phymask;        /* PHYs we manage */
        int             phyoffset;      /* PHYs register offset */
        int             numports;       /* number of ports */
        int             ifpport[MII_NPHY];
        int             *portphy;
        char            **ifname;
        device_t        **miibus;
        if_t *ifp;
        struct callout  callout_tick;
        etherswitch_info_t      info;
};

#define UKSWITCH_LOCK(_sc)                      \
            mtx_lock(&(_sc)->sc_mtx)
#define UKSWITCH_UNLOCK(_sc)                    \
            mtx_unlock(&(_sc)->sc_mtx)
#define UKSWITCH_LOCK_ASSERT(_sc, _what)        \
            mtx_assert(&(_sc)->sc_mtx, (_what))
#define UKSWITCH_TRYLOCK(_sc)                   \
            mtx_trylock(&(_sc)->sc_mtx)

#if defined(DEBUG)
#define DPRINTF(dev, args...) device_printf(dev, args)
#else
#define DPRINTF(dev, args...)
#endif

static inline int ukswitch_portforphy(struct ukswitch_softc *, int);
static void ukswitch_tick(void *);
static int ukswitch_ifmedia_upd(if_t);
static void ukswitch_ifmedia_sts(if_t, struct ifmediareq *);

static int
ukswitch_probe(device_t dev)
{
        struct ukswitch_softc *sc;

        sc = device_get_softc(dev);
        bzero(sc, sizeof(*sc));

        device_set_desc(dev, "Generic MDIO switch driver");
        return (BUS_PROBE_DEFAULT);
}

static int
ukswitch_attach_phys(struct ukswitch_softc *sc)
{
        int phy, port = 0, err = 0;
        char name[IFNAMSIZ];

        /* PHYs need an interface, so we generate a dummy one */
        snprintf(name, IFNAMSIZ, "%sport", device_get_nameunit(sc->sc_dev));
        for (phy = 0; phy < MII_NPHY; phy++) {
                if (((1 << phy) & sc->phymask) == 0)
                        continue;
                sc->ifpport[phy] = port;
                sc->portphy[port] = phy;
                sc->ifp[port] = if_alloc(IFT_ETHER);
                if_setsoftc(sc->ifp[port], sc);
                if_setflags(sc->ifp[port], IFF_UP | IFF_BROADCAST |
                    IFF_DRV_RUNNING | IFF_SIMPLEX);
                sc->ifname[port] = malloc(strlen(name)+1, M_UKSWITCH, M_WAITOK);
                bcopy(name, sc->ifname[port], strlen(name)+1);
                if_initname(sc->ifp[port], sc->ifname[port], port);
                sc->miibus[port] = malloc(sizeof(device_t), M_UKSWITCH,
                    M_WAITOK | M_ZERO);
                err = mii_attach(sc->sc_dev, sc->miibus[port], sc->ifp[port],
                    ukswitch_ifmedia_upd, ukswitch_ifmedia_sts, \
                    BMSR_DEFCAPMASK, phy + sc->phyoffset, MII_OFFSET_ANY, 0);
                DPRINTF(sc->sc_dev, "%s attached to pseudo interface %s\n",
                    device_get_nameunit(*sc->miibus[port]),
                    if_name(sc->ifp[port]));
                if (err != 0) {
                        device_printf(sc->sc_dev,
                            "attaching PHY %d failed\n",
                            phy);
                        break;
                }
                sc->info.es_nports = port + 1;
                if (++port >= sc->numports)
                        break;
        }
        return (err);
}

static int
ukswitch_attach(device_t dev)
{
        struct ukswitch_softc *sc;
        int err = 0;

        sc = device_get_softc(dev);

        sc->sc_dev = dev;
        mtx_init(&sc->sc_mtx, "ukswitch", NULL, MTX_DEF);
        strlcpy(sc->info.es_name, device_get_desc(dev),
            sizeof(sc->info.es_name));

        /* XXX Defaults */
        sc->numports = 6;
        sc->phymask = 0x0f;
        sc->phyoffset = 0;
        sc->cpuport = -1;
        sc->media = 100;

        (void) resource_int_value(device_get_name(dev), device_get_unit(dev),
            "numports", &sc->numports);
        (void) resource_int_value(device_get_name(dev), device_get_unit(dev),
            "phymask", &sc->phymask);
        (void) resource_int_value(device_get_name(dev), device_get_unit(dev),
            "phyoffset", &sc->phyoffset);
        (void) resource_int_value(device_get_name(dev), device_get_unit(dev),
            "cpuport", &sc->cpuport);
        (void) resource_int_value(device_get_name(dev), device_get_unit(dev),
            "media", &sc->media);

        /* Support only fast and giga ethernet. */
        if (sc->media != 100 && sc->media != 1000)
                sc->media = 100;

        if (sc->cpuport != -1)
                /* Always attach the cpu port. */
                sc->phymask |= (1 << sc->cpuport);

        /* We do not support any vlan groups. */
        sc->info.es_nvlangroups = 0;

        sc->ifp = malloc(sizeof(if_t) * sc->numports, M_UKSWITCH,
            M_WAITOK | M_ZERO);
        sc->ifname = malloc(sizeof(char *) * sc->numports, M_UKSWITCH,
            M_WAITOK | M_ZERO);
        sc->miibus = malloc(sizeof(device_t *) * sc->numports, M_UKSWITCH,
            M_WAITOK | M_ZERO);
        sc->portphy = malloc(sizeof(int) * sc->numports, M_UKSWITCH,
            M_WAITOK | M_ZERO);

        /*
         * Attach the PHYs and complete the bus enumeration.
         */
        err = ukswitch_attach_phys(sc);
        if (err != 0)
                return (err);

        bus_identify_children(dev);
        bus_enumerate_hinted_children(dev);
        bus_attach_children(dev);
        
        callout_init(&sc->callout_tick, 0);

        ukswitch_tick(sc);
        
        return (err);
}

static int
ukswitch_detach(device_t dev)
{
        struct ukswitch_softc *sc = device_get_softc(dev);
        int error, i, port;

        error = bus_generic_detach(dev);
        if (error != 0)
                return (error);

        callout_drain(&sc->callout_tick);

        for (i=0; i < MII_NPHY; i++) {
                if (((1 << i) & sc->phymask) == 0)
                        continue;
                port = ukswitch_portforphy(sc, i);
                if (sc->ifp[port] != NULL)
                        if_free(sc->ifp[port]);
                free(sc->ifname[port], M_UKSWITCH);
                free(sc->miibus[port], M_UKSWITCH);
        }

        free(sc->portphy, M_UKSWITCH);
        free(sc->miibus, M_UKSWITCH);
        free(sc->ifname, M_UKSWITCH);
        free(sc->ifp, M_UKSWITCH);

        mtx_destroy(&sc->sc_mtx);

        return (0);
}

/*
 * Convert PHY number to port number.
 */
static inline int
ukswitch_portforphy(struct ukswitch_softc *sc, int phy)
{

        return (sc->ifpport[phy]);
}

static inline struct mii_data *
ukswitch_miiforport(struct ukswitch_softc *sc, int port)
{

        if (port < 0 || port > sc->numports)
                return (NULL);
        return (device_get_softc(*sc->miibus[port]));
}

static inline if_t 
ukswitch_ifpforport(struct ukswitch_softc *sc, int port)
{

        if (port < 0 || port > sc->numports)
                return (NULL);
        return (sc->ifp[port]);
}

/*
 * Poll the status for all PHYs.
 */
static void
ukswitch_miipollstat(struct ukswitch_softc *sc)
{
        int i, port;
        struct mii_data *mii;
        struct mii_softc *miisc;

        UKSWITCH_LOCK_ASSERT(sc, MA_NOTOWNED);

        for (i = 0; i < MII_NPHY; i++) {
                if (((1 << i) & sc->phymask) == 0)
                        continue;
                port = ukswitch_portforphy(sc, i);
                if ((*sc->miibus[port]) == NULL)
                        continue;
                mii = device_get_softc(*sc->miibus[port]);
                LIST_FOREACH(miisc, &mii->mii_phys, mii_list) {
                        if (IFM_INST(mii->mii_media.ifm_cur->ifm_media) !=
                            miisc->mii_inst)
                                continue;
                        ukphy_status(miisc);
                        mii_phy_update(miisc, MII_POLLSTAT);
                }
        }
}

static void
ukswitch_tick(void *arg)
{
        struct ukswitch_softc *sc = arg;

        ukswitch_miipollstat(sc);
        callout_reset(&sc->callout_tick, hz, ukswitch_tick, sc);
}

static void
ukswitch_lock(device_t dev)
{
        struct ukswitch_softc *sc = device_get_softc(dev);

        UKSWITCH_LOCK_ASSERT(sc, MA_NOTOWNED);
        UKSWITCH_LOCK(sc);
}

static void
ukswitch_unlock(device_t dev)
{
        struct ukswitch_softc *sc = device_get_softc(dev);

        UKSWITCH_LOCK_ASSERT(sc, MA_OWNED);
        UKSWITCH_UNLOCK(sc);
}

static etherswitch_info_t *
ukswitch_getinfo(device_t dev)
{
        struct ukswitch_softc *sc = device_get_softc(dev);
        
        return (&sc->info);
}

static int
ukswitch_getport(device_t dev, etherswitch_port_t *p)
{
        struct ukswitch_softc *sc = device_get_softc(dev);
        struct mii_data *mii;
        struct ifmediareq *ifmr = &p->es_ifmr;
        int err, phy;

        if (p->es_port < 0 || p->es_port >= sc->numports)
                return (ENXIO);
        p->es_pvid = 0;

        phy = sc->portphy[p->es_port];
        mii = ukswitch_miiforport(sc, p->es_port);
        if (sc->cpuport != -1 && phy == sc->cpuport) {
                /* fill in fixed values for CPU port */
                p->es_flags |= ETHERSWITCH_PORT_CPU;
                ifmr->ifm_count = 0;
                if (sc->media == 100)
                        ifmr->ifm_current = ifmr->ifm_active =
                            IFM_ETHER | IFM_100_TX | IFM_FDX;
                else
                        ifmr->ifm_current = ifmr->ifm_active =
                            IFM_ETHER | IFM_1000_T | IFM_FDX;
                ifmr->ifm_mask = 0;
                ifmr->ifm_status = IFM_ACTIVE | IFM_AVALID;
        } else if (mii != NULL) {
                err = ifmedia_ioctl(mii->mii_ifp, &p->es_ifr,
                    &mii->mii_media, SIOCGIFMEDIA);
                if (err)
                        return (err);
        } else {
                return (ENXIO);
        }
        return (0);
}

static int
ukswitch_setport(device_t dev, etherswitch_port_t *p)
{
        struct ukswitch_softc *sc = device_get_softc(dev);
        struct ifmedia *ifm;
        struct mii_data *mii;
        if_t ifp;
        int err;

        if (p->es_port < 0 || p->es_port >= sc->numports)
                return (ENXIO);

        if (sc->portphy[p->es_port] == sc->cpuport)
                return (ENXIO);

        mii = ukswitch_miiforport(sc, p->es_port);
        if (mii == NULL)
                return (ENXIO);

        ifp = ukswitch_ifpforport(sc, p->es_port);

        ifm = &mii->mii_media;
        err = ifmedia_ioctl(ifp, &p->es_ifr, ifm, SIOCSIFMEDIA);
        return (err);
}

static int
ukswitch_getvgroup(device_t dev, etherswitch_vlangroup_t *vg)
{

        /* Not supported. */
        vg->es_vid = 0;
        vg->es_member_ports = 0;
        vg->es_untagged_ports = 0;
        vg->es_fid = 0;
        return (0);
}

static int
ukswitch_setvgroup(device_t dev, etherswitch_vlangroup_t *vg)
{

        /* Not supported. */
        return (0);
}

static void
ukswitch_statchg(device_t dev)
{

        DPRINTF(dev, "%s\n", __func__);
}

static int
ukswitch_ifmedia_upd(if_t ifp)
{
        struct ukswitch_softc *sc = if_getsoftc(ifp);
        struct mii_data *mii = ukswitch_miiforport(sc, if_getdunit(ifp));

        DPRINTF(sc->sc_dev, "%s\n", __func__);
        if (mii == NULL)
                return (ENXIO);
        mii_mediachg(mii);
        return (0);
}

static void
ukswitch_ifmedia_sts(if_t ifp, struct ifmediareq *ifmr)
{
        struct ukswitch_softc *sc = if_getsoftc(ifp);
        struct mii_data *mii = ukswitch_miiforport(sc, if_getdunit(ifp));

        DPRINTF(sc->sc_dev, "%s\n", __func__);

        if (mii == NULL)
                return;
        mii_pollstat(mii);
        ifmr->ifm_active = mii->mii_media_active;
        ifmr->ifm_status = mii->mii_media_status;
}

static int
ukswitch_readphy(device_t dev, int phy, int reg)
{
        struct ukswitch_softc *sc;
        int data;

        sc = device_get_softc(dev);
        UKSWITCH_LOCK_ASSERT(sc, MA_NOTOWNED);

        if (phy < 0 || phy >= 32)
                return (ENXIO);
        if (reg < 0 || reg >= 32)
                return (ENXIO);

        UKSWITCH_LOCK(sc);
        data = MDIO_READREG(device_get_parent(dev), phy, reg);
        UKSWITCH_UNLOCK(sc);

        return (data);
}

static int
ukswitch_writephy(device_t dev, int phy, int reg, int data)
{
        struct ukswitch_softc *sc;
        int err;

        sc = device_get_softc(dev);
        UKSWITCH_LOCK_ASSERT(sc, MA_NOTOWNED);

        if (phy < 0 || phy >= 32)
                return (ENXIO);
        if (reg < 0 || reg >= 32)
                return (ENXIO);

        UKSWITCH_LOCK(sc);
        err = MDIO_WRITEREG(device_get_parent(dev), phy, reg, data);
        UKSWITCH_UNLOCK(sc);

        return (err);
}

static int
ukswitch_readreg(device_t dev, int addr)
{
        struct ukswitch_softc *sc __diagused;

        sc = device_get_softc(dev);
        UKSWITCH_LOCK_ASSERT(sc, MA_OWNED);

        /* Not supported. */
        return (0);
}

static int
ukswitch_writereg(device_t dev, int addr, int value)
{
        struct ukswitch_softc *sc __diagused;

        sc = device_get_softc(dev);
        UKSWITCH_LOCK_ASSERT(sc, MA_OWNED);

        /* Not supported. */
        return (0);
}

static device_method_t ukswitch_methods[] = {
        /* Device interface */
        DEVMETHOD(device_probe,         ukswitch_probe),
        DEVMETHOD(device_attach,        ukswitch_attach),
        DEVMETHOD(device_detach,        ukswitch_detach),
        
        /* bus interface */
        DEVMETHOD(bus_add_child,        device_add_child_ordered),
        
        /* MII interface */
        DEVMETHOD(miibus_readreg,       ukswitch_readphy),
        DEVMETHOD(miibus_writereg,      ukswitch_writephy),
        DEVMETHOD(miibus_statchg,       ukswitch_statchg),

        /* MDIO interface */
        DEVMETHOD(mdio_readreg,         ukswitch_readphy),
        DEVMETHOD(mdio_writereg,        ukswitch_writephy),

        /* etherswitch interface */
        DEVMETHOD(etherswitch_lock,     ukswitch_lock),
        DEVMETHOD(etherswitch_unlock,   ukswitch_unlock),
        DEVMETHOD(etherswitch_getinfo,  ukswitch_getinfo),
        DEVMETHOD(etherswitch_readreg,  ukswitch_readreg),
        DEVMETHOD(etherswitch_writereg, ukswitch_writereg),
        DEVMETHOD(etherswitch_readphyreg,       ukswitch_readphy),
        DEVMETHOD(etherswitch_writephyreg,      ukswitch_writephy),
        DEVMETHOD(etherswitch_getport,  ukswitch_getport),
        DEVMETHOD(etherswitch_setport,  ukswitch_setport),
        DEVMETHOD(etherswitch_getvgroup,        ukswitch_getvgroup),
        DEVMETHOD(etherswitch_setvgroup,        ukswitch_setvgroup),

        DEVMETHOD_END
};

DEFINE_CLASS_0(ukswitch, ukswitch_driver, ukswitch_methods,
    sizeof(struct ukswitch_softc));

DRIVER_MODULE(ukswitch, mdio, ukswitch_driver, 0, 0);
DRIVER_MODULE(miibus, ukswitch, miibus_driver, 0, 0);
DRIVER_MODULE(mdio, ukswitch, mdio_driver, 0, 0);
DRIVER_MODULE(etherswitch, ukswitch, etherswitch_driver, 0, 0);
MODULE_VERSION(ukswitch, 1);
MODULE_DEPEND(ukswitch, miibus, 1, 1, 1); /* XXX which versions? */
MODULE_DEPEND(ukswitch, etherswitch, 1, 1, 1); /* XXX which versions? */