gianfar: Don't reset TBI<->SerDes link if it's already up

[linux-2.6-omap-h63xx.git] / drivers / net / gianfar.c

diff --git a/drivers/net/gianfar.c b/drivers/net/gianfar.c
index 64b201134fdb85e5f93248644fecfaf7e91969fc..83a5cb6aa23b1fc5c4426a9863303be6bb10dad3 100644 (file)
--- a/drivers/net/gianfar.c
+++ b/drivers/net/gianfar.c
@@ -586,6 +586,18 @@ static void gfar_configure_serdes(struct net_device *dev)
        struct gfar_mii __iomem *regs =
                        (void __iomem *)&priv->regs->gfar_mii_regs;
        int tbipa = gfar_read(&priv->regs->tbipa);
+       struct mii_bus *bus = gfar_get_miibus(priv);
+
+       if (bus)
+               mutex_lock(&bus->mdio_lock);
+
+       /* If the link is already up, we must already be ok, and don't need to
+        * configure and reset the TBI<->SerDes link.  Maybe U-Boot configured
+        * everything for us?  Resetting it takes the link down and requires
+        * several seconds for it to come back.
+        */
+       if (gfar_local_mdio_read(regs, tbipa, MII_BMSR) & BMSR_LSTATUS)
+               goto done;
 
        /* Single clk mode, mii mode off(for serdes communication) */
        gfar_local_mdio_write(regs, tbipa, MII_TBICON, TBICON_CLK_SELECT);
@@ -596,6 +608,10 @@ static void gfar_configure_serdes(struct net_device *dev)
 
        gfar_local_mdio_write(regs, tbipa, MII_BMCR, BMCR_ANENABLE |
                        BMCR_ANRESTART | BMCR_FULLDPLX | BMCR_SPEED1000);
+
+       done:
+       if (bus)
+               mutex_unlock(&bus->mdio_lock);
 }
 
 static void init_registers(struct net_device *dev)