/*-
 * SPDX-License-Identifier: BSD-4-Clause
 *
 * Copyright (c) 1997, 1998, 1999
 *      Bill Paul <wpaul@ctr.columbia.edu>.  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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by Bill Paul.
 * 4. Neither the name of the author nor the names of any co-contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY Bill Paul 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 Bill Paul OR THE VOICES IN HIS HEAD
 * 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/cdefs.h>
/*
 * driver for RealTek 8139 internal PHYs
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/socket.h>
#include <sys/bus.h>
#include <sys/taskqueue.h>      /* XXXGL: if_rlreg.h contamination */

#include <net/if.h>
#include <net/if_arp.h>
#include <net/if_media.h>

#include <dev/mii/mii.h>
#include <dev/mii/miivar.h>
#include "miidevs.h"

#include <machine/bus.h>
#include <dev/rl/if_rlreg.h>

#include "miibus_if.h"

static int rlphy_probe(device_t);
static int rlphy_attach(device_t);

static device_method_t rlphy_methods[] = {
        /* device interface */
        DEVMETHOD(device_probe,         rlphy_probe),
        DEVMETHOD(device_attach,        rlphy_attach),
        DEVMETHOD(device_detach,        mii_phy_detach),
        DEVMETHOD(device_shutdown,      bus_generic_shutdown),
        DEVMETHOD_END
};

static driver_t rlphy_driver = {
        "rlphy",
        rlphy_methods,
        sizeof(struct mii_softc)
};

DRIVER_MODULE(rlphy, miibus, rlphy_driver, 0, 0);

static int      rlphy_service(struct mii_softc *, struct mii_data *, int);
static void     rlphy_status(struct mii_softc *);

/*
 * RealTek internal PHYs don't have vendor/device ID registers;
 * re(4) and rl(4) fake up a return value of all zeros.
 */
static const struct mii_phydesc rlintphys[] = {
        { 0, 0, "RealTek internal media interface" },
        MII_PHY_END
};

static const struct mii_phydesc rlphys[] = {
        MII_PHY_DESC(yyREALTEK, RTL8201L),
        MII_PHY_DESC(REALTEK, RTL8201E),
        MII_PHY_DESC(xxICPLUS, IP101),
        MII_PHY_END
};

static const struct mii_phy_funcs rlphy_funcs = {
        rlphy_service,
        rlphy_status,
        mii_phy_reset
};

static int
rlphy_probe(device_t dev)
{
        int rv;

        rv = mii_phy_dev_probe(dev, rlphys, BUS_PROBE_DEFAULT);
#ifndef __HAIKU__
        if (rv <= 0)
                return (rv);
#else /* __HAIKU__ */
        /* our BUS_PROBE_* constants are > 0 since errors are < 0 */
        if (rv > 0)
                return (rv);
#endif

        if (mii_dev_mac_match(dev, "rl") || mii_dev_mac_match(dev, "re"))
                return (mii_phy_dev_probe(dev, rlintphys, BUS_PROBE_DEFAULT));
        return (ENXIO);
}

static int
rlphy_attach(device_t dev)
{

        /*
         * The RealTek PHY can never be isolated.
         */
        mii_phy_dev_attach(dev, MIIF_NOISOLATE | MIIF_NOMANPAUSE,
            &rlphy_funcs, 1);
        return (0);
}

static int
rlphy_service(struct mii_softc *sc, struct mii_data *mii, int cmd)
{

        switch (cmd) {
        case MII_POLLSTAT:
                break;

        case MII_MEDIACHG:
                mii_phy_setmedia(sc);
                break;

        case MII_TICK:
                /*
                 * The RealTek PHY's autonegotiation doesn't need to be
                 * kicked; it continues in the background.
                 */
                break;
        }

        /* Update the media status. */
        PHY_STATUS(sc);

        /* Callback if something changed. */
        mii_phy_update(sc, cmd);
        return (0);
}

static void
rlphy_status(struct mii_softc *phy)
{
        struct mii_data *mii = phy->mii_pdata;
        struct ifmedia_entry *ife = mii->mii_media.ifm_cur;
        int bmsr, bmcr, anlpar;

        mii->mii_media_status = IFM_AVALID;
        mii->mii_media_active = IFM_ETHER;

        bmsr = PHY_READ(phy, MII_BMSR) | PHY_READ(phy, MII_BMSR);
        if (bmsr & BMSR_LINK)
                mii->mii_media_status |= IFM_ACTIVE;

        bmcr = PHY_READ(phy, MII_BMCR);
        if (bmcr & BMCR_ISO) {
                mii->mii_media_active |= IFM_NONE;
                mii->mii_media_status = 0;
                return;
        }

        if (bmcr & BMCR_LOOP)
                mii->mii_media_active |= IFM_LOOP;

        if (bmcr & BMCR_AUTOEN) {
                /*
                 * NWay autonegotiation takes the highest-order common
                 * bit of the ANAR and ANLPAR (i.e. best media advertised
                 * both by us and our link partner).
                 */
                if ((bmsr & BMSR_ACOMP) == 0) {
                        /* Erg, still trying, I guess... */
                        mii->mii_media_active |= IFM_NONE;
                        return;
                }

                if ((anlpar = PHY_READ(phy, MII_ANAR) &
                    PHY_READ(phy, MII_ANLPAR))) {
                        if (anlpar & ANLPAR_TX_FD)
                                mii->mii_media_active |= IFM_100_TX|IFM_FDX;
                        else if (anlpar & ANLPAR_T4)
                                mii->mii_media_active |= IFM_100_T4|IFM_HDX;
                        else if (anlpar & ANLPAR_TX)
                                mii->mii_media_active |= IFM_100_TX|IFM_HDX;
                        else if (anlpar & ANLPAR_10_FD)
                                mii->mii_media_active |= IFM_10_T|IFM_FDX;
                        else if (anlpar & ANLPAR_10)
                                mii->mii_media_active |= IFM_10_T|IFM_HDX;
                        else
                                mii->mii_media_active |= IFM_NONE;
                        if ((mii->mii_media_active & IFM_FDX) != 0)
                                mii->mii_media_active |=
                                    mii_phy_flowstatus(phy);
                        return;
                }
                /*
                 * If the other side doesn't support NWAY, then the
                 * best we can do is determine if we have a 10Mbps or
                 * 100Mbps link. There's no way to know if the link
                 * is full or half duplex, so we default to half duplex
                 * and hope that the user is clever enough to manually
                 * change the media settings if we're wrong.
                 */

                /*
                 * The RealTek PHY supports non-NWAY link speed
                 * detection, however it does not report the link
                 * detection results via the ANLPAR or BMSR registers.
                 * (What? RealTek doesn't do things the way everyone
                 * else does? I'm just shocked, shocked I tell you.)
                 * To determine the link speed, we have to do one
                 * of two things:
                 *
                 * - If this is a standalone RealTek RTL8201(L) or
                 *   workalike PHY, we can determine the link speed by
                 *   testing bit 0 in the magic, vendor-specific register
                 *   at offset 0x19.
                 *
                 * - If this is a RealTek MAC with integrated PHY, we
                 *   can test the 'SPEED10' bit of the MAC's media status
                 *   register.
                 */
                if (!(phy->mii_mpd_model == 0 && phy->mii_mpd_rev == 0)) {
                        if (PHY_READ(phy, 0x0019) & 0x01)
                                mii->mii_media_active |= IFM_100_TX;
                        else
                                mii->mii_media_active |= IFM_10_T;
                } else {
                        if (PHY_READ(phy, RL_MEDIASTAT) &
                            RL_MEDIASTAT_SPEED10)
                                mii->mii_media_active |= IFM_10_T;
                        else
                                mii->mii_media_active |= IFM_100_TX;
                }
                mii->mii_media_active |= IFM_HDX;
        } else
                mii->mii_media_active = ife->ifm_media;
}