net/mlx4_en: adding loopback support

Device must be in promiscuous mode or DMAC must be same as the host MAC, or
else packet will be dropped by the HW rx filtering.

Signed-off-by: Amir Vadai <amirv@mellanox.co.il>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 21 insertions, 2 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
index 78d776bc355c..4c5bbb3aad31 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
@@ -974,6 +974,21 @@ static int mlx4_en_change_mtu(struct net_device *dev, int new_mtu)
         return 0;
 }
 
+static int mlx4_en_set_features(struct net_device *netdev,
+                netdev_features_t features)
+{
+        struct mlx4_en_priv *priv = netdev_priv(netdev);
+
+        if (features & NETIF_F_LOOPBACK)
+                priv->ctrl_flags |= cpu_to_be32(MLX4_WQE_CTRL_FORCE_LOOPBACK);
+        else
+                priv->ctrl_flags &=
+                        cpu_to_be32(~MLX4_WQE_CTRL_FORCE_LOOPBACK);
+
+        return 0;
+
+}
+
 static const struct net_device_ops mlx4_netdev_ops = {
         .ndo_open               = mlx4_en_open,
         .ndo_stop               = mlx4_en_close,
@@ -990,6 +1005,7 @@ static const struct net_device_ops mlx4_netdev_ops = {
 #ifdef CONFIG_NET_POLL_CONTROLLER
         .ndo_poll_controller    = mlx4_en_netpoll,
 #endif
+        .ndo_set_features       = mlx4_en_set_features,
 };
 
 int mlx4_en_init_netdev(struct mlx4_en_dev *mdev, int port,
@@ -1022,6 +1038,8 @@ int mlx4_en_init_netdev(struct mlx4_en_dev *mdev, int port,
         priv->port = port;
         priv->port_up = false;
         priv->flags = prof->flags;
+        priv->ctrl_flags = cpu_to_be32(MLX4_WQE_CTRL_CQ_UPDATE |
+                        MLX4_WQE_CTRL_SOLICITED);
         priv->tx_ring_num = prof->tx_ring_num;
         priv->rx_ring_num = prof->rx_ring_num;
         priv->mac_index = -1;
@@ -1088,6 +1106,7 @@ int mlx4_en_init_netdev(struct mlx4_en_dev *mdev, int port,
         dev->features = dev->hw_features | NETIF_F_HIGHDMA |
                         NETIF_F_HW_VLAN_TX | NETIF_F_HW_VLAN_RX |
                         NETIF_F_HW_VLAN_FILTER;
+        dev->hw_features |= NETIF_F_LOOPBACK;
 
         mdev->pndev[port] = dev;
 
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_tx.c b/drivers/net/ethernet/mellanox/mlx4/en_tx.c
index 3094f940b928..807c2186548c 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_tx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_tx.c
@@ -679,8 +679,7 @@ netdev_tx_t mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev)
         tx_desc->ctrl.vlan_tag = cpu_to_be16(vlan_tag);
         tx_desc->ctrl.ins_vlan = MLX4_WQE_CTRL_INS_VLAN * !!vlan_tag;
         tx_desc->ctrl.fence_size = (real_size / 16) & 0x3f;
-        tx_desc->ctrl.srcrb_flags = cpu_to_be32(MLX4_WQE_CTRL_CQ_UPDATE |
-                                                MLX4_WQE_CTRL_SOLICITED);
+        tx_desc->ctrl.srcrb_flags = priv->ctrl_flags;
         if (likely(skb->ip_summed == CHECKSUM_PARTIAL)) {
                 tx_desc->ctrl.srcrb_flags |= cpu_to_be32(MLX4_WQE_CTRL_IP_CSUM |
                                                          MLX4_WQE_CTRL_TCP_UDP_CSUM);
diff --git a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
index d2dd97fa091f..ea2ba6899e9a 100644
--- a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
+++ b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
@@ -453,6 +453,7 @@ struct mlx4_en_priv {
         int base_qpn;
 
         struct mlx4_en_rss_map rss_map;
+        u32 ctrl_flags;
         u32 flags;
 #define MLX4_EN_FLAG_PROMISC    0x1
 #define MLX4_EN_FLAG_MC_PROMISC 0x2