[PATCH 2/2] gianfar: Don't reset TBI<->SerDes link if it's already up
From: Trent Piepho <hidden>
Date: 2008-10-31 01:17:49
Also in:
linuxppc-dev
Subsystem:
networking drivers, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
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 <redacted> Acked-by: Andy Fleming <redacted> --- 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