From: Remi Pommarel repk@triplefau.lt
[ Upstream commit b723bd933980f4956dabc8a8d84b3e83be8d094c ]
ACS (auto PAD/FCS stripping) removes FCS off 802.3 packets (LLC) so that there is no need to manually strip it for such packets. The enhanced DMA descriptors allow to flag LLC packets so that the receiving callback can use that to strip FCS manually or not. On the other hand, normal descriptors do not support that.
Thus in order to not truncate LLC packet ACS should be disabled when using normal DMA descriptors.
Fixes: 47dd7a540b8a0 ("net: add support for STMicroelectronics Ethernet controllers.") Signed-off-by: Remi Pommarel repk@triplefau.lt Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.c +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.c @@ -24,6 +24,7 @@ static void dwmac1000_core_init(struct mac_device_info *hw, struct net_device *dev) { + struct stmmac_priv *priv = netdev_priv(dev); void __iomem *ioaddr = hw->pcsr; u32 value = readl(ioaddr + GMAC_CONTROL); int mtu = dev->mtu; @@ -35,7 +36,7 @@ static void dwmac1000_core_init(struct m * Broadcom tags can look like invalid LLC/SNAP packets and cause the * hardware to truncate packets on reception. */ - if (netdev_uses_dsa(dev)) + if (netdev_uses_dsa(dev) || !priv->plat->enh_desc) value &= ~GMAC_CONTROL_ACS;
if (mtu > 1500)