The link may be up already via the chip's reset strapping, or though action
of U-Boot, or from the last time the interface was brought up. Resetting
the link causes it to go down for several seconds. This can significantly
increase the time from power-on to DHCP completion and a device being
accessible to the network.
Signed-off-by: Trent Piepho <[EMAIL PROTECTED]>
Acked-by: Andy Fleming <[EMAIL PROTECTED]>
---
drivers/net/gianfar.c | 9 +++++++++
1 files changed, 9 insertions(+), 0 deletions(-)
diff --git a/drivers/net/gianfar.c b/drivers/net/gianfar.c
index 249541a..83a5cb6 100644
--- a/drivers/net/gianfar.c
+++ b/drivers/net/gianfar.c
@@ -591,6 +591,14 @@ static void gfar_configure_serdes(struct net_device *dev)
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);
@@ -601,6 +609,7 @@ 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);
}
--
1.5.4.1
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