From: Tariq Toukan <tariqt@mellanox.com>
Date: Tue, 10 Oct 2017 16:54:30 +0300
Subject: net/mlx5e: Check support before TC swap in ETS init
Patch-mainline: v4.15-rc9
Git-commit: 4b7d4363f14a0398eca48c7e96e46120c5eb6a96
References: bsc#1046303 FATE#322944

Should not do the following swap between TCs 0 and 1
when max num of TCs is 1:
tclass[prio=0]=1, tclass[prio=1]=0, tclass[prio=i]=i (for i>1)

Fixes: 08fb1dacdd76 ("net/mlx5e: Support DCBNL IEEE ETS")
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/mellanox/mlx5/core/en_dcbnl.c |    8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

--- a/drivers/net/ethernet/mellanox/mlx5/core/en_dcbnl.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_dcbnl.c
@@ -799,9 +799,11 @@ static void mlx5e_ets_init(struct mlx5e_
 		ets.prio_tc[i] = i;
 	}
 
-	/* tclass[prio=0]=1, tclass[prio=1]=0, tclass[prio=i]=i (for i>1) */
-	ets.prio_tc[0] = 1;
-	ets.prio_tc[1] = 0;
+	if (ets.ets_cap > 1) {
+		/* tclass[prio=0]=1, tclass[prio=1]=0, tclass[prio=i]=i (for i>1) */
+		ets.prio_tc[0] = 1;
+		ets.prio_tc[1] = 0;
+	}
 
 	err = mlx5e_dcbnl_ieee_setets_core(priv, &ets);
 	if (err)