[ 031/187] sky2: fix checksum bit management on some chips

Greg Kroah-Hartman
2012-07-12T23:45:54Z

From: stephen hemminger <shemminger@vyatta.com>

[ Upstream commit 5ff0feac88ced864f44adb145142269196fa79d9 ]

The newer flavors of Yukon II use a different method for receive
checksum offload. This is indicated in the driver by the SKY2_HW_NEW_LE
flag. On these newer chips, the BMU_ENA_RX_CHKSUM should not be set.

The driver would get incorrectly toggle the bit, enabling the old
checksum logic on these chips and cause a BUG_ON() assertion. If
receive checksum was toggled via ethtool.

Reported-by: Kirill Smelkov <kirr@mns.spb.ru>
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/ethernet/marvell/sky2.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)

--- a/drivers/net/ethernet/marvell/sky2.c
+++ b/drivers/net/ethernet/marvell/sky2.c
@@ -4381,10 +4381,12 @@ static int sky2_set_features(struct net_
struct sky2_port *sky2 = netdev_priv(dev);
netdev_features_t changed = dev->features ^ features;

- if (changed & NETIF_F_RXCSUM) {
- bool on = features & NETIF_F_RXCSUM;
- sky2_write32(sky2->hw, Q_ADDR(rxqaddr[sky2->port], Q_CSR),
- on ? BMU_ENA_RX_CHKSUM : BMU_DIS_RX_CHKSUM);
+ if ((changed & NETIF_F_RXCSUM) &&
+ !(sky2->hw->flags & SKY2_HW_NEW_LE)) {
+ sky2_write32(sky2->hw,
+ Q_ADDR(rxqaddr[sky2->port], Q_CSR),
+ (features & NETIF_F_RXCSUM)
+ ? BMU_ENA_RX_CHKSUM : BMU_DIS_RX_CHKSUM);
}

if (changed & NETIF_F_RXHASH)