/*      $NetBSD: rlphy.c,v 1.39 2020/03/15 23:04:50 thorpej Exp $       */
/*      $OpenBSD: rlphy.c,v 1.20 2005/07/31 05:27:30 pvalchev Exp $     */

/*
 * Copyright (c) 1998, 1999 Jason L. Wright (jason@thought.net)
 * 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 ``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.
 */

/*
 * Driver for the internal PHY found on RTL8139 based nics, based
 * on drivers for the 'exphy' (Internal 3Com phys) and 'nsphy'
 * (National Semiconductor DP83840).
 */

/*
 * Ported to NetBSD by Juan Romero Pardines <xtraeme@NetBSD.org>
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: rlphy.c,v 1.39 2020/03/15 23:04:50 thorpej Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/device.h>
#include <sys/socket.h>
#include <sys/errno.h>

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

#include <dev/mii/mii.h>
#include <dev/mii/miivar.h>
#include <dev/mii/miidevs.h>
#include <sys/bus.h>
#include <dev/ic/rtl81x9reg.h>

struct rlphy_softc {
        struct mii_softc sc_mii;
        int sc_rtl8201;
};

static int      rlphymatch(device_t, cfdata_t, void *);
static void     rlphyattach(device_t, device_t, void *);

CFATTACH_DECL_NEW(rlphy, sizeof(struct rlphy_softc),
    rlphymatch, rlphyattach, mii_phy_detach, mii_phy_activate);

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

const struct mii_phy_funcs rlphy_funcs = {
        rlphy_service, rlphy_status, rlphy_reset,
};

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 int
rlphymatch(device_t parent, cfdata_t match, void *aux)
{
        struct mii_attach_args *ma = aux;
        struct mii_data *mii = ma->mii_data;

        if (mii->mii_instance != 0)
                return 0;

        if (mii_phy_match(ma, rlphys) != NULL)
                return 10;

        if (MII_OUI(ma->mii_id1, ma->mii_id2) != 0 ||
            MII_MODEL(ma->mii_id2) != 0)
                return 0;

        if (!device_is_a(parent, "rtk") && !device_is_a(parent, "re"))
                return 0;

        /*
         * A "real" phy should get preference, but on the 8139 there
         * is no phyid register.
         */
        return 5;
}

static void
rlphyattach(device_t parent, device_t self, void *aux)
{
        struct rlphy_softc *rsc = device_private(self);
        struct mii_softc *sc = &rsc->sc_mii;
        struct mii_attach_args *ma = aux;
        struct mii_data *mii = ma->mii_data;

        aprint_naive("\n");
        if (MII_MODEL(ma->mii_id2) == MII_MODEL_yyREALTEK_RTL8201L) {
                rsc->sc_rtl8201 = 1;
                aprint_normal(": %s, rev. %d\n", MII_STR_yyREALTEK_RTL8201L,
                    MII_REV(ma->mii_id2));
        } else if (MII_MODEL(ma->mii_id2) == MII_MODEL_REALTEK_RTL8201E) {
                rsc->sc_rtl8201 = 1;
                aprint_normal(": %s, rev. %d\n", MII_STR_REALTEK_RTL8201E,
                    MII_REV(ma->mii_id2));
        } else if (MII_MODEL(ma->mii_id2) == MII_MODEL_xxICPLUS_IP101) {
                aprint_normal(": %s, rev. %d\n", MII_STR_xxICPLUS_IP101,
                    MII_REV(ma->mii_id2));
        } else
                aprint_normal(": Realtek internal PHY\n");

        sc->mii_dev = self;
        sc->mii_inst = mii->mii_instance;
        sc->mii_phy = ma->mii_phyno;
        sc->mii_funcs = &rlphy_funcs;
        sc->mii_pdata = mii;
        sc->mii_flags = ma->mii_flags;

        sc->mii_flags |= MIIF_NOISOLATE;

        mii_lock(mii);

        PHY_RESET(sc);

        PHY_READ(sc, MII_BMSR, &sc->mii_capabilities);
        sc->mii_capabilities &= ma->mii_capmask;

        mii_unlock(mii);

        mii_phy_add_media(sc);
}

static int
rlphy_service(struct mii_softc *sc, struct mii_data *mii, int cmd)
{
        struct ifmedia_entry *ife = mii->mii_media.ifm_cur;

        /* Can't isolate the RTL8139 phy, so it has to be the only one. */
        if (IFM_INST(ife->ifm_media) != sc->mii_inst)
                panic("rlphy_service: attempt to isolate phy");

        KASSERT(mii_locked(mii));

        switch (cmd) {
        case MII_POLLSTAT:
                break;

        case MII_MEDIACHG:
                /* If the interface is not up, don't do anything. */
                if ((mii->mii_ifp->if_flags & IFF_UP) == 0)
                        break;

                mii_phy_setmedia(sc);
                break;

        case MII_TICK:
                /* Is the interface even up? */
                if ((mii->mii_ifp->if_flags & IFF_UP) == 0)
                        return 0;

                /* Only used for autonegotiation. */
                if (IFM_SUBTYPE(ife->ifm_media) != IFM_AUTO)
                        break;

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

        case MII_DOWN:
                mii_phy_down(sc);
                return 0;
        }

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

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

static void
rlphy_status(struct mii_softc *sc)
{
        struct rlphy_softc *rsc = (void *)sc;
        struct mii_data *mii = sc->mii_pdata;
        struct ifmedia_entry *ife = mii->mii_media.ifm_cur;
        uint16_t bmsr, bmcr, anar, anlpar, result, reg;

        KASSERT(mii_locked(mii));

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

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

        PHY_READ(sc, MII_BMCR, &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;
                }

                PHY_READ(sc, MII_ANAR, &anar);
                PHY_READ(sc, MII_ANLPAR, &anlpar);
                result = anar & anlpar;
                if (result != 0) {
                        if (result & ANLPAR_TX_FD)
                                mii->mii_media_active |= IFM_100_TX | IFM_FDX;
                        else if (result & ANLPAR_T4)
                                mii->mii_media_active |= IFM_100_T4 | IFM_HDX;
                        else if (result & ANLPAR_TX)
                                mii->mii_media_active |= IFM_100_TX | IFM_HDX;
                        else if (result & ANLPAR_10_FD)
                                mii->mii_media_active |= IFM_10_T | IFM_FDX;
                        else if (result & ANLPAR_10)
                                mii->mii_media_active |= IFM_10_T | IFM_HDX;
                        else
                                mii->mii_media_active |= IFM_NONE;
                        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 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 (rsc->sc_rtl8201) {
                        PHY_READ(sc, 0x0019, &reg);
                        if (reg & 0x01)
                                mii->mii_media_active |= IFM_100_TX;
                        else
                                mii->mii_media_active |= IFM_10_T;
                } else {
                        PHY_READ(sc, RTK_MEDIASTAT, &reg);
                        if (reg & RTK_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;
}

static void
rlphy_reset(struct mii_softc *sc)
{

        KASSERT(mii_locked(sc->mii_pdata));

        mii_phy_reset(sc);

        /*
         * XXX RealTek PHY doesn't set the BMCR properly after
         * XXX reset, which breaks autonegotiation.
         */
        PHY_WRITE(sc, MII_BMCR, BMCR_AUTOEN);
}