/*      $NetBSD: mii.c,v 1.40 2005/12/11 12:22:42 christos Exp $        */

/*-
 * Copyright (c) 1998, 2000 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
 * NASA Ames Research Center.
 *
 * 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 the NetBSD
 *      Foundation, Inc. and its contributors.
 * 4. Neither the name of The NetBSD Foundation nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
 *
 * $FreeBSD: src/sys/dev/mii/mii.c,v 1.6.2.2 2002/08/19 16:56:33 ambrisko Exp $
 */

/*
 * MII bus layer, glues MII-capable network interface drivers to sharable
 * PHY drivers.  This exports an interface compatible with BSD/OS 3.0's,
 * plus some NetBSD extensions.
 */

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

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

#include "mii.h"
#include "miivar.h"

#include "miibus_if.h"

static int      miibus_probe(device_t);
static int      miibus_attach(device_t);
static int      miibus_detach(device_t);
static int      miibus_readreg(device_t, int, int);
static int      miibus_writereg(device_t, int, int, int);
static void     miibus_statchg(device_t);
static void     miibus_mediainit(device_t);

static device_method_t miibus_methods[] = {
        /* device interface */
        DEVMETHOD(device_probe,         miibus_probe),
        DEVMETHOD(device_attach,        miibus_attach),
        DEVMETHOD(device_detach,        miibus_detach),
        DEVMETHOD(device_shutdown,      bus_generic_shutdown),

        /* bus interface */
        DEVMETHOD(bus_print_child,      bus_generic_print_child),
        DEVMETHOD(bus_driver_added,     bus_generic_driver_added),

        /* MII interface */
        DEVMETHOD(miibus_readreg,       miibus_readreg),
        DEVMETHOD(miibus_writereg,      miibus_writereg),
        DEVMETHOD(miibus_statchg,       miibus_statchg),    
        DEVMETHOD(miibus_mediainit,     miibus_mediainit),    

        DEVMETHOD_END
};

devclass_t miibus_devclass;

driver_t miibus_driver = {
        "miibus",
        miibus_methods,
        sizeof(struct mii_data)
};

/*
 * Check to see if there is a PHY at this address.  Note,
 * many braindead PHYs report 0/0 in their ID registers,
 * so we test for media in the BMSR.
 */
static __inline int
miibus_no_phy(device_t dev, const struct mii_probe_args *args, int phyno)
{
        int bmsr;

        if ((args->mii_probemask & (1 << phyno)) == 0)
                return 1;

        bmsr = MIIBUS_READREG(dev, phyno, MII_BMSR);
        return (bmsr == 0 || bmsr == 0xffff ||
                (bmsr & (BMSR_MEDIAMASK | BMSR_EXTSTAT)) == 0);
}

/*
 * Helper function used by network interface drivers, attaches PHYs
 * to the network interface driver parent.
 */

static int
miibus_probe(device_t dev)
{
        struct mii_attach_args ma, *args;
        const struct mii_probe_args *probe_args;
        struct mii_data *mii;
        device_t child = NULL, parent;

        probe_args = device_get_ivars(dev);

        mii = device_get_softc(dev);
        parent = device_get_parent(dev);
        LIST_INIT(&mii->mii_phys);
        bzero(&ma, sizeof(ma));

        for (ma.mii_phyno = 0; ma.mii_phyno < MII_NPHY; ma.mii_phyno++) {
                if (miibus_no_phy(parent, probe_args, ma.mii_phyno))
                        continue;

                /*
                 * Extract the IDs. Braindead PHYs will be handled by
                 * the `ukphy' driver, as we have no ID information to
                 * match on.
                 */
                ma.mii_id1 = MIIBUS_READREG(parent, ma.mii_phyno,
                    MII_PHYIDR1);
                ma.mii_id2 = MIIBUS_READREG(parent, ma.mii_phyno,
                    MII_PHYIDR2);

                ma.mii_data = mii;
                ma.mii_capmask = probe_args->mii_capmask;
                ma.mii_privtag = probe_args->mii_privtag;
                ma.mii_priv = probe_args->mii_priv;

                args = kmalloc(sizeof(struct mii_attach_args), M_DEVBUF,
                    M_WAITOK);
                *args = ma;
                child = device_add_child(dev, NULL, -1);
                device_set_ivars(child, args);
        }
        if (child == NULL)
                return ENXIO;

        device_set_desc(dev, "MII bus");
        return 0;
}

static int
miibus_attach(device_t dev)
{
        const struct mii_probe_args *probe_args;
        struct mii_data *mii;

        mii = device_get_softc(dev);
        mii->mii_ifp = device_get_softc(device_get_parent(dev));

        probe_args = device_get_ivars(dev);
        ifmedia_init(&mii->mii_media, IFM_IMASK,
            probe_args->mii_ifmedia_upd, probe_args->mii_ifmedia_sts);

        bus_generic_attach(dev);
        return 0;
}

static int
miibus_detach(device_t dev)
{
        struct mii_data *mii;

        bus_generic_detach(dev);
        mii = device_get_softc(dev);
        ifmedia_removeall(&mii->mii_media);
        mii->mii_ifp = NULL;

        return 0;
}

static int
miibus_readreg(device_t dev, int phy, int reg)
{
        device_t parent;

        parent = device_get_parent(dev);
        return MIIBUS_READREG(parent, phy, reg);
}

static int
miibus_writereg(device_t dev, int phy, int reg, int data)
{
        device_t parent;

        parent = device_get_parent(dev);
        return MIIBUS_WRITEREG(parent, phy, reg, data);
}

static void
miibus_statchg(device_t dev)
{
        device_t parent;

        parent = device_get_parent(dev);
        MIIBUS_STATCHG(parent);
}

static void
miibus_mediainit(device_t dev)
{
        struct mii_data *mii;
        struct ifmedia_entry *m;
        int media = 0;

        /* Poke the parent in case it has any media of its own to add. */
        MIIBUS_MEDIAINIT(device_get_parent(dev));

        mii = device_get_softc(dev);
        for (m = LIST_FIRST(&mii->mii_media.ifm_list); m != NULL;
             m = LIST_NEXT(m, ifm_list)) {
                media = m->ifm_media;
                if (media == (IFM_ETHER|IFM_AUTO))
                        break;
        }
        ifmedia_set(&mii->mii_media, media);
}

int
mii_phy_probe(device_t dev, device_t *child,
    ifm_change_cb_t ifmedia_upd, ifm_stat_cb_t ifmedia_sts)
{
        struct mii_probe_args args;

        mii_probe_args_init(&args, ifmedia_upd, ifmedia_sts);
        return mii_probe(dev, child, &args);
}

int
mii_probe(device_t dev, device_t *child, const struct mii_probe_args *args0)
{
        struct mii_probe_args *args;
        int i;

        args = kmalloc(sizeof(*args), M_DEVBUF, M_WAITOK);
        *args = *args0;

        *child = device_add_child(dev, "miibus", -1);
        device_set_ivars(*child, args);

        for (i = 0; i < MII_NPHY; i++) {
                if (!miibus_no_phy(dev, args0, i))
                        break;
        }

        if (i == MII_NPHY) {
                device_delete_child(dev, *child);
                *child = NULL;
                return ENXIO;
        }

        bus_generic_attach(dev);
        return 0;
}

void
mii_probe_args_init(struct mii_probe_args *args,
    ifm_change_cb_t ifmedia_upd, ifm_stat_cb_t ifmedia_sts)
{
        memset(args, 0, sizeof(*args));

        args->mii_ifmedia_upd = ifmedia_upd;
        args->mii_ifmedia_sts = ifmedia_sts;
        args->mii_probemask = MII_PROBEMASK_DEFAULT;
        args->mii_capmask = MII_CAPMASK_DEFAULT;
        args->mii_privtag = MII_PRIVTAG_NONE;
}

/*
 * Media changed; notify all PHYs.
 */
int
mii_mediachg(struct mii_data *mii)
{
        struct mii_softc *child;
        int rv;

        mii->mii_media_status = 0;
        mii->mii_media_active = IFM_NONE;

        for (child = LIST_FIRST(&mii->mii_phys); child != NULL;
             child = LIST_NEXT(child, mii_list)) {
                rv = (*child->mii_service)(child, mii, MII_MEDIACHG);
                if (rv) {
                        return rv;
                } else {
                        /* Reset autonegotiation timer. */
                        child->mii_ticks = 0;
                }
        }
        return 0;
}

/*
 * Call the PHY tick routines, used during autonegotiation.
 */
void
mii_tick(struct mii_data *mii)
{
        struct mii_softc *child;

        for (child = LIST_FIRST(&mii->mii_phys); child != NULL;
             child = LIST_NEXT(child, mii_list))
                (*child->mii_service)(child, mii, MII_TICK);
}

/*
 * Get media status from PHYs.
 */
void
mii_pollstat(struct mii_data *mii)
{
        struct mii_softc *child;

        mii->mii_media_status = 0;
        mii->mii_media_active = IFM_NONE;

        for (child = LIST_FIRST(&mii->mii_phys); child != NULL;
             child = LIST_NEXT(child, mii_list))
                (*child->mii_service)(child, mii, MII_POLLSTAT);
}

static moduledata_t miibus_mod = { "miibus" };

DECLARE_MODULE(miibus, miibus_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE);
MODULE_VERSION(miibus, 1);