mlx4_en: Added self diagnostics test implementation

The selftest includes 5 features:
1. Interrupt test: Executing commands and receiving command completion
   on all our interrupt vectors.
2. Link test: Verifying we are connected to valid link partner.
3. Speed test: Check that we negotiated link speed correctly.
4. Registers test: Activate HW health check command.
5. Loopback test: Send a packet on loopback interface and catch it on RX side.

Signed-off-by: Yevgeny Petrilin <yevgenyp@mellanox.co.il>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 16 insertions, 0 deletions

diff --git a/drivers/net/mlx4/en_tx.c b/drivers/net/mlx4/en_tx.c
index 3deabd1d0357..b875f9c38848 100644
--- a/drivers/net/mlx4/en_tx.c
+++ b/drivers/net/mlx4/en_tx.c
@@ -600,6 +600,9 @@ netdev_tx_t mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev)
         struct mlx4_wqe_data_seg *data;
         struct skb_frag_struct *frag;
         struct mlx4_en_tx_info *tx_info;
+        struct ethhdr *ethh;
+        u64 mac;
+        u32 mac_l, mac_h;
         int tx_ind = 0;
         int nr_txbb;
         int desc_size;
@@ -679,6 +682,19 @@ netdev_tx_t mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev)
                 priv->port_stats.tx_chksum_offload++;
         }
 
+        if (unlikely(priv->validate_loopback)) {
+                /* Copy dst mac address to wqe */
+                skb_reset_mac_header(skb);
+                ethh = eth_hdr(skb);
+                if (ethh && ethh->h_dest) {
+                        mac = mlx4_en_mac_to_u64(ethh->h_dest);
+                        mac_h = (u32) ((mac & 0xffff00000000ULL) >> 16);
+                        mac_l = (u32) (mac & 0xffffffff);
+                        tx_desc->ctrl.srcrb_flags |= cpu_to_be32(mac_h);
+                        tx_desc->ctrl.imm = cpu_to_be32(mac_l);
+                }
+        }
+
         /* Handle LSO (TSO) packets */
         if (lso_header_size) {
                 /* Mark opcode as LSO */