When driver is run for the first time there would be no established

link such that calling dc_setcfg() right after media change would
be meaningless unless controller in question is not Davicom DM9102.
Ideally dc_setcfg() should be called when speed/duplex is resolved
otherwise it would reprogram controller with wrong speed/duplex
information.  Because MII status change callback already calls
dc_setcfg() I think calling dc_setcfg() in dc_init_locked() is
wrong.  For instance, it would take some time to establish a link
after mii_mediachg(), so blindly calling dc_setcfg() right after
mii_mediachg() will always yield wrong media configuration.

Extend dc_ifmedia_upd() to handle media change and still allow
21143 and Davidcom controllers program speed/duplex regardless of
current resolved speed/duplex of link. In theory 21143 may not need
to call dc_setcfg() right after media change, but leave it as it is
because there are too many variants to test that change.  Probably
dc(4) shall need a PHY reset in dc_ifmedia_upd() but it's hard to
verify correctness of the change.

This change reliably makes ULi M5263 establish a link.

While I'm here correctly report media change result. Previously it
always reported a success.

1 files changed, 28 insertions, 16 deletions

diff --git a/sys/dev/dc/if_dc.c b/sys/dev/dc/if_dc.c
index 452f5d33264a..38f4ca58c6df 100644
--- a/sys/dev/dc/if_dc.c
+++ b/sys/dev/dc/if_dc.c
@@ -252,6 +252,7 @@ static void dc_stop(struct dc_softc *);
 static void dc_watchdog(void *);
 static int dc_shutdown(device_t);
 static int dc_ifmedia_upd(struct ifnet *);
+static int dc_ifmedia_upd_locked(struct dc_softc *);
 static void dc_ifmedia_sts(struct ifnet *, struct ifmediareq *);
 
 static int dc_dma_alloc(struct dc_softc *);
@@ -3740,8 +3741,7 @@ dc_init_locked(struct dc_softc *sc)
 	ifp->if_drv_flags |= IFF_DRV_RUNNING;
 	ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
 
-	mii_mediachg(mii);
-	dc_setcfg(sc, sc->dc_if_media);
+	dc_ifmedia_upd_locked(sc);
 
 	/* Clear missed frames and overflow counter. */
 	CSR_READ_4(sc, DC_FRAMESDISCARDED);
@@ -3767,25 +3767,37 @@ static int
 dc_ifmedia_upd(struct ifnet *ifp)
 {
 	struct dc_softc *sc;
-	struct mii_data *mii;
-	struct ifmedia *ifm;
+	int error;
 
 	sc = ifp->if_softc;
-	mii = device_get_softc(sc->dc_miibus);
 	DC_LOCK(sc);
-	mii_mediachg(mii);
-	ifm = &mii->mii_media;
-
-	if (DC_IS_INTEL(sc))
-		dc_setcfg(sc, ifm->ifm_media);
-	else if (DC_IS_DAVICOM(sc) &&
-	    IFM_SUBTYPE(ifm->ifm_media) == IFM_HPNA_1)
-		dc_setcfg(sc, ifm->ifm_media);
-	else
-		sc->dc_link = 0;
+	error = dc_ifmedia_upd_locked(sc);
 	DC_UNLOCK(sc);
+	return (error);
+}
 
-	return (0);
+static int
+dc_ifmedia_upd_locked(struct dc_softc *sc)
+{
+	struct mii_data *mii;
+	struct ifmedia *ifm;
+	int error;
+
+	DC_LOCK_ASSERT(sc);
+
+	sc->dc_link = 0;
+	mii = device_get_softc(sc->dc_miibus);
+	error = mii_mediachg(mii);
+	if (error == 0) {
+		ifm = &mii->mii_media;
+		if (DC_IS_INTEL(sc))
+			dc_setcfg(sc, ifm->ifm_media);
+		else if (DC_IS_DAVICOM(sc) &&
+		    IFM_SUBTYPE(ifm->ifm_media) == IFM_HPNA_1)
+			dc_setcfg(sc, ifm->ifm_media);
+	}
+
+	return (error);
 }
 
 /*