From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from az33egw02.freescale.net (az33egw02.freescale.net [192.88.158.103]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "az33egw02.freescale.net", Issuer "Thawte Premium Server CA" (verified OK)) by ozlabs.org (Postfix) with ESMTPS id 6274ADDE11 for ; Fri, 31 Oct 2008 12:17:49 +1100 (EST) From: Trent Piepho To: netdev@vger.kernel.org Subject: [PATCH 2/2] gianfar: Don't reset TBI<->SerDes link if it's already up Date: Thu, 30 Oct 2008 18:17:07 -0700 Message-Id: <1225415827-8167-2-git-send-email-tpiepho@freescale.com> In-Reply-To: References: Cc: linuxppc-dev@ozlabs.org, Nate Case , Trent Piepho List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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 Acked-by: Andy Fleming --- 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