net/mlx4_en: Add RX-FCS support

Enabled when device supports KEEP FCS. When the flag is set, Ethernet FCS
is appended to the end of the frame, controlled by ethtool.

Signed-off-by: Muhammad Mahajna <muhammadm@mellanox.com>
Signed-off-by: Ido Shamay <idos@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 31 insertions, 7 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
index be9e07a72193..333af3405a80 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
@@ -2195,15 +2195,19 @@ static int mlx4_en_set_features(struct net_device *netdev,
                 netdev_features_t features)
 {
         struct mlx4_en_priv *priv = netdev_priv(netdev);
+        bool reset = false;
         int ret = 0;
 
+        if (DEV_FEATURE_CHANGED(netdev, features, NETIF_F_RXFCS)) {
+                en_info(priv, "Turn %s RX-FCS\n",
+                        (features & NETIF_F_RXFCS) ? "ON" : "OFF");
+                reset = true;
+        }
+
         if (DEV_FEATURE_CHANGED(netdev, features, NETIF_F_HW_VLAN_CTAG_RX)) {
                 en_info(priv, "Turn %s RX vlan strip offload\n",
                         (features & NETIF_F_HW_VLAN_CTAG_RX) ? "ON" : "OFF");
-                ret = mlx4_en_reset_config(netdev, priv->hwtstamp_config,
-                                           features);
-                if (ret)
-                        return ret;
+                reset = true;
         }
 
         if (DEV_FEATURE_CHANGED(netdev, features, NETIF_F_HW_VLAN_CTAG_TX))
@@ -2216,8 +2220,14 @@ static int mlx4_en_set_features(struct net_device *netdev,
                 mlx4_en_update_loopback_state(netdev, features);
         }
 
-        return 0;
+        if (reset) {
+                ret = mlx4_en_reset_config(netdev, priv->hwtstamp_config,
+                                           features);
+                if (ret)
+                        return ret;
+        }
 
+        return 0;
 }
 
 static int mlx4_en_set_vf_mac(struct net_device *dev, int queue, u8 *mac)
@@ -2901,6 +2911,9 @@ int mlx4_en_init_netdev(struct mlx4_en_dev *mdev, int port,
         dev->hw_features |= NETIF_F_LOOPBACK |
                         NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_RX;
 
+        if (mdev->dev->caps.flags & MLX4_DEV_CAP_FLAG_FCS_KEEP)
+                dev->hw_features |= NETIF_F_RXFCS;
+
         if (mdev->dev->caps.steering_mode ==
             MLX4_STEERING_MODE_DEVICE_MANAGED &&
             mdev->dev->caps.dmfs_high_steer_mode != MLX4_STEERING_DMFS_A0_STATIC)
@@ -2997,7 +3010,8 @@ int mlx4_en_reset_config(struct net_device *dev,
 
         if (priv->hwtstamp_config.tx_type == ts_config.tx_type &&
             priv->hwtstamp_config.rx_filter == ts_config.rx_filter &&
-            !DEV_FEATURE_CHANGED(dev, features, NETIF_F_HW_VLAN_CTAG_RX))
+            !DEV_FEATURE_CHANGED(dev, features, NETIF_F_HW_VLAN_CTAG_RX) &&
+            !DEV_FEATURE_CHANGED(dev, features, NETIF_F_RXFCS))
                 return 0; /* Nothing to change */
 
         if (DEV_FEATURE_CHANGED(dev, features, NETIF_F_HW_VLAN_CTAG_RX) &&
@@ -3036,6 +3050,13 @@ int mlx4_en_reset_config(struct net_device *dev,
                         dev->features &= ~NETIF_F_HW_VLAN_CTAG_RX;
         }
 
+        if (DEV_FEATURE_CHANGED(dev, features, NETIF_F_RXFCS)) {
+                if (features & NETIF_F_RXFCS)
+                        dev->features |= NETIF_F_RXFCS;
+                else
+                        dev->features &= ~NETIF_F_RXFCS;
+        }
+
         /* RX vlan offload and RX time-stamping can't co-exist !
          * Regardless of the caller's choice,
          * Turn Off RX vlan offload in case of time-stamping is ON
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
index 698d60de1255..79b1501e7951 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
@@ -1116,7 +1116,10 @@ static int mlx4_en_config_rss_qp(struct mlx4_en_priv *priv, int qpn,
         /* Cancel FCS removal if FW allows */
         if (mdev->dev->caps.flags & MLX4_DEV_CAP_FLAG_FCS_KEEP) {
                 context->param3 |= cpu_to_be32(1 << 29);
-                ring->fcs_del = ETH_FCS_LEN;
+                if (priv->dev->features & NETIF_F_RXFCS)
+                        ring->fcs_del = 0;
+                else
+                        ring->fcs_del = ETH_FCS_LEN;
         } else
                 ring->fcs_del = 0;