[PATCH 3.13 123/259] net: mvneta: fix operation in 10 Mbit/s mode

From: Kamal Mostafa
Date: Fri Aug 08 2014 - 17:01:44 EST


3.13.11.6 -stable review patch. If anyone has any objections, please let me know.

------------------

From: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx>

commit 4d12bc63ab5e48c1d78fa13883cf6fefcea3afb1 upstream.

As reported by Maggie Mae Roxas, the mvneta driver doesn't behave
properly in 10 Mbit/s mode. This is due to a misconfiguration of the
MVNETA_GMAC_AUTONEG_CONFIG register: bit MVNETA_GMAC_CONFIG_MII_SPEED
must be set for a 100 Mbit/s speed, but cleared for a 10 Mbit/s speed,
which the driver was not properly doing. This commit adjusts that by
setting the MVNETA_GMAC_CONFIG_MII_SPEED bit only in 100 Mbit/s mode,
and relying on the fact that all the speed related bits of this
register are cleared at the beginning of the mvneta_adjust_link()
function.

This problem exists since c5aff18204da0 ("net: mvneta: driver for
Marvell Armada 370/XP network unit") which is the commit that
introduced the mvneta driver in the kernel.

Fixes: c5aff18204da0 ("net: mvneta: driver for Marvell Armada 370/XP network unit")
Reported-by: Maggie Mae Roxas <maggie.mae.roxas@xxxxxxxxx>
Cc: Maggie Mae Roxas <maggie.mae.roxas@xxxxxxxxx>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
---
drivers/net/ethernet/marvell/mvneta.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c
index d7aa22a..1c8dd19 100644
--- a/drivers/net/ethernet/marvell/mvneta.c
+++ b/drivers/net/ethernet/marvell/mvneta.c
@@ -2367,7 +2367,7 @@ static void mvneta_adjust_link(struct net_device *ndev)

if (phydev->speed == SPEED_1000)
val |= MVNETA_GMAC_CONFIG_GMII_SPEED;
- else
+ else if (phydev->speed == SPEED_100)
val |= MVNETA_GMAC_CONFIG_MII_SPEED;

mvreg_write(pp, MVNETA_GMAC_AUTONEG_CONFIG, val);
--
1.9.1

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