* Copyright 2001 Wasabi Systems, Inc.

/* $NetBSD: amhphy.c,v 1.27 2024/02/08 19:44:08 andvar 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 the 10BASE-T portion of the AMD Am79c901 PHY.
*/

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: amhphy.c,v 1.27 2024/02/08 19:44:08 andvar 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 <dev/mii/amhphyreg.h>

static int amhphymatch(device_t, cfdata_t, void *);
static void amhphyattach(device_t, device_t, void *);

CFATTACH_DECL_NEW(amhphy, sizeof(struct mii_softc),
amhphymatch, amhphyattach, mii_phy_detach, mii_phy_activate);

static int amhphy_service(struct mii_softc *, struct mii_data *, int);
static void amhphy_status(struct mii_softc *);

static const struct mii_phy_funcs amhphy_funcs = {
amhphy_service, amhphy_status, mii_phy_reset,
};

static const struct mii_phydesc amhphys[] = {
MII_PHY_DESC(yyAMD, 79c901),
MII_PHY_END,
};

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

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

return 0;
}

static void
amhphyattach(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, amhphys);
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 = &amhphy_funcs;
sc->mii_pdata = mii;
sc->mii_flags = ma->mii_flags;

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
amhphy_service(struct mii_softc *sc, struct mii_data *mii, int cmd)
{
struct ifmedia_entry *ife = mii->mii_media.ifm_cur;
uint16_t reg;

KASSERT(mii_locked(mii));

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) {
PHY_READ(sc, MII_BMCR, &reg);
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
amhphy_status(struct mii_softc *sc)
{
struct mii_data *mii = sc->mii_pdata;
struct ifmedia_entry *ife = mii->mii_media.ifm_cur;
uint16_t bmsr, bmcr, ssr;

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_AMHPHY_SSR, &ssr);

if (ssr & SSR_LS)
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) {
/*
* The media status bits are only valid if autonegotiation
* has completed (or it's disabled).
*/
if ((bmsr & BMSR_ACOMP) == 0) {
/* Erg, still trying, I guess... */
mii->mii_media_active |= IFM_NONE;
return;
}

if (ssr & SSR_S) {
/*
* This shouldn't really ever happen, since it's
* a 10BASE-T only PHY. But the bit exists, according
* to the documentation, so we pay attention to it.
*/
mii->mii_media_active |= IFM_100_TX;
} else
mii->mii_media_active |= IFM_10_T;
if (ssr & SSR_FD)
mii->mii_media_active |= IFM_FDX;
else
mii->mii_media_active |= IFM_HDX;
} else
mii->mii_media_active = ife->ifm_media;
}