net/mlx4_en: Enable DCB ETS ops only when supported by the firmware

Enable the DCB ETS ops only when supported by the firmware. For older firmware/cards
which don't support ETS, advertize only PFC DCB ops.
Signed-off-by: Eugenia Emantayev <eugenia@mellanox.co.il>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlx4/en_dcb_nl.c

@@ -253,3 +253,11 @@ const struct dcbnl_rtnl_ops mlx4_en_dcbnl_ops = {
 	.getdcbx	= mlx4_en_dcbnl_getdcbx,
 	.setdcbx	= mlx4_en_dcbnl_setdcbx,
 };
+
+const struct dcbnl_rtnl_ops mlx4_en_dcbnl_pfc_ops = {
+	.ieee_getpfc	= mlx4_en_dcbnl_ieee_getpfc,
+	.ieee_setpfc	= mlx4_en_dcbnl_ieee_setpfc,
+
+	.getdcbx	= mlx4_en_dcbnl_getdcbx,
+	.setdcbx	= mlx4_en_dcbnl_setdcbx,
+};

drivers/net/ethernet/mellanox/mlx4/en_netdev.c

@@ -2013,8 +2013,14 @@ int mlx4_en_init_netdev(struct mlx4_en_dev *mdev, int port,
 	INIT_WORK(&priv->linkstate_task, mlx4_en_linkstate);
 	INIT_DELAYED_WORK(&priv->stats_task, mlx4_en_do_get_stats);
 #ifdef CONFIG_MLX4_EN_DCB
-	if (!mlx4_is_slave(priv->mdev->dev))
-		dev->dcbnl_ops = &mlx4_en_dcbnl_ops;
+	if (!mlx4_is_slave(priv->mdev->dev)) {
+		if (mdev->dev->caps.flags & MLX4_DEV_CAP_FLAG_SET_ETH_SCHED) {
+			dev->dcbnl_ops = &mlx4_en_dcbnl_ops;
+		} else {
+			en_info(priv, "enabling only PFC DCB ops\n");
+			dev->dcbnl_ops = &mlx4_en_dcbnl_pfc_ops;
+		}
+	}
 #endif
 
 	for (i = 0; i < MLX4_EN_MAC_HASH_SIZE; ++i)

drivers/net/ethernet/mellanox/mlx4/fw.c

@@ -109,6 +109,7 @@ static void dump_dev_cap_flags(struct mlx4_dev *dev, u64 flags)
 		[41] = "Unicast VEP steering support",
 		[42] = "Multicast VEP steering support",
 		[48] = "Counters support",
+		[53] = "Port ETS Scheduler support",
 		[55] = "Port link type sensing support",
 		[59] = "Port management change event support",
 		[61] = "64 byte EQE support",

drivers/net/ethernet/mellanox/mlx4/mlx4_en.h

@@ -624,6 +624,7 @@ int mlx4_en_QUERY_PORT(struct mlx4_en_dev *mdev, u8 port);
 
 #ifdef CONFIG_MLX4_EN_DCB
 extern const struct dcbnl_rtnl_ops mlx4_en_dcbnl_ops;
+extern const struct dcbnl_rtnl_ops mlx4_en_dcbnl_pfc_ops;
 #endif
 
 int mlx4_en_setup_tc(struct net_device *dev, u8 up);

include/linux/mlx4/device.h

@@ -140,6 +140,7 @@ enum {
 	MLX4_DEV_CAP_FLAG_VEP_UC_STEER	= 1LL << 41,
 	MLX4_DEV_CAP_FLAG_VEP_MC_STEER	= 1LL << 42,
 	MLX4_DEV_CAP_FLAG_COUNTERS	= 1LL << 48,
+	MLX4_DEV_CAP_FLAG_SET_ETH_SCHED = 1LL << 53,
 	MLX4_DEV_CAP_FLAG_SENSE_SUPPORT	= 1LL << 55,
 	MLX4_DEV_CAP_FLAG_PORT_MNG_CHG_EV = 1LL << 59,
 	MLX4_DEV_CAP_FLAG_64B_EQE	= 1LL << 61,