/*	$NetBSD: pnaphy.c,v 1.21 2016/07/07 06:55:41 msaitoh Exp $	*/

/*
 * Copyright 2001 Wasabi Systems, Inc.
 * All rights reserved.
 *
 * Written by Jason R. Thorpe for Wasabi Systems, Inc.
 *
 * 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 for the NetBSD Project by
 *	Wasabi Systems, Inc.
 * 4. The name of Wasabi Systems, Inc. may not be used to endorse
 *    or promote products derived from this software without specific prior
 *    written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``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 WASABI SYSTEMS, INC
 * 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 generic HomePNA 1.0 PHYs.
 *
 * HomePNA 1.0 PHYs are pretty simple -- they support exactly one
 * media type, and don't do autonegotiation.
 *
 * HomePNA PHYs often have vendor-specific registers for tuning
 * the network connection, but we don't deal with any of that
 * at all.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: pnaphy.c,v 1.21 2016/07/07 06:55:41 msaitoh 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>

static int	pnaphymatch(device_t, cfdata_t, void *);
static void	pnaphyattach(device_t, device_t, void *);

CFATTACH_DECL_NEW(pnaphy, sizeof(struct mii_softc),
    pnaphymatch, pnaphyattach, mii_phy_detach, mii_phy_activate);

static int	pnaphy_service(struct mii_softc *, struct mii_data *, int);
static void	pnaphy_status(struct mii_softc *);

static const struct mii_phy_funcs pnaphy_funcs = {
	pnaphy_service, pnaphy_status, mii_phy_reset,
};

static const struct mii_phydesc pnaphys[] = {
	{ MII_OUI_yyAMD,		MII_MODEL_yyAMD_79c901home,
	  MII_STR_yyAMD_79c901home },

	{ 0,				0,
	  NULL },
};

static int
pnaphymatch(device_t parent, cfdata_t match, void *aux)
{
	struct mii_attach_args *ma = aux;

	if (mii_phy_match(ma, pnaphys) != NULL) {
		/*
		 * Match higher than ukphy, but lower than a specific
		 * driver would match.
		 */
		return (2);
	}

	return (0);
}

static void
pnaphyattach(device_t parent, device_t self, void *aux)
{
	struct mii_softc *sc = device_private(self);
	struct mii_attach_args *ma = aux;
	struct mii_data *mii = ma->mii_data;
	const struct mii_phydesc *mpd;

	mpd = mii_phy_match(ma, pnaphys);
	aprint_naive(": Media interface\n");
	aprint_normal(": %s, rev. %d\n", mpd->mpd_name, MII_REV(ma->mii_id2));

	sc->mii_dev = self;
	sc->mii_inst = mii->mii_instance;
	sc->mii_phy = ma->mii_phyno;
	sc->mii_funcs = &pnaphy_funcs;
	sc->mii_pdata = mii;
	sc->mii_flags = ma->mii_flags | MIIF_IS_HPNA; /* force HomePNA */
	sc->mii_anegticks = MII_ANEGTICKS;

	PHY_RESET(sc);

	sc->mii_capabilities = PHY_READ(sc, MII_BMSR) & ma->mii_capmask;
	aprint_normal_dev(self, "");
	if ((sc->mii_capabilities & BMSR_MEDIAMASK) == 0)
		aprint_error("no media present");
	else
		mii_phy_add_media(sc);
	aprint_normal("\n");
}

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

	switch (cmd) {
	case MII_POLLSTAT:
		/*
		 * If we're not polling our PHY instance, just return.
		 */
		if (IFM_INST(ife->ifm_media) != sc->mii_inst)
			return (0);
		break;

	case MII_MEDIACHG:
		/*
		 * If the media indicates a different PHY instance,
		 * isolate ourselves.
		 */
		if (IFM_INST(ife->ifm_media) != sc->mii_inst) {
			reg = PHY_READ(sc, MII_BMCR);
			PHY_WRITE(sc, MII_BMCR, reg | BMCR_ISO);
			return (0);
		}

		/*
		 * 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:
		/*
		 * If we're not currently selected, just return.
		 */
		if (IFM_INST(ife->ifm_media) != sc->mii_inst)
			return (0);

		if (mii_phy_tick(sc) == EJUSTRETURN)
			return (0);
		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
pnaphy_status(struct mii_softc *sc)
{
	struct mii_data *mii = sc->mii_pdata;
	struct ifmedia_entry *ife = mii->mii_media.ifm_cur;
	int bmsr, bmcr;

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

	bmsr = PHY_READ(sc, MII_BMSR) | PHY_READ(sc, MII_BMSR);

	if (bmsr & BMSR_LINK)
		mii->mii_media_status |= IFM_ACTIVE;

	bmcr = PHY_READ(sc, 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;

	/*
	 * On HomePNA PHYs, the current media is always the selected
	 * media.
	 *
	 * XXX May not be the case w/ HomePNA 2.
	 */
	mii->mii_media_active = ife->ifm_media;
}