3 files changed, 6 insertions, 26 deletions

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
index c5856f4d6b8b..f064789f3240 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
@@ -405,21 +405,6 @@ static int mlxsw_sp_port_dev_addr_init(struct mlxsw_sp_port *mlxsw_sp_port)
 					  mlxsw_sp_port->dev->dev_addr);
 }
 
-static int mlxsw_sp_port_max_mtu_get(struct mlxsw_sp_port *mlxsw_sp_port, int *p_max_mtu)
-{
-	struct mlxsw_sp *mlxsw_sp = mlxsw_sp_port->mlxsw_sp;
-	char pmtu_pl[MLXSW_REG_PMTU_LEN];
-	int err;
-
-	mlxsw_reg_pmtu_pack(pmtu_pl, mlxsw_sp_port->local_port, 0);
-	err = mlxsw_reg_query(mlxsw_sp->core, MLXSW_REG(pmtu), pmtu_pl);
-	if (err)
-		return err;
-
-	*p_max_mtu = mlxsw_reg_pmtu_max_mtu_get(pmtu_pl);
-	return 0;
-}
-
 static int mlxsw_sp_port_mtu_set(struct mlxsw_sp_port *mlxsw_sp_port, u16 mtu)
 {
 	struct mlxsw_sp *mlxsw_sp = mlxsw_sp_port->mlxsw_sp;
@@ -1725,13 +1710,6 @@ static int mlxsw_sp_port_create(struct mlxsw_sp *mlxsw_sp, u16 local_port,
 		goto err_max_speed_get;
 	}
 
-	err = mlxsw_sp_port_max_mtu_get(mlxsw_sp_port, &mlxsw_sp_port->max_mtu);
-	if (err) {
-		dev_err(mlxsw_sp->bus_info->dev, "Port %d: Failed to get maximum MTU\n",
-			mlxsw_sp_port->local_port);
-		goto err_port_max_mtu_get;
-	}
-
 	err = mlxsw_sp_port_mtu_set(mlxsw_sp_port, ETH_DATA_LEN);
 	if (err) {
 		dev_err(mlxsw_sp->bus_info->dev, "Port %d: Failed to set MTU\n",
@@ -1875,7 +1853,6 @@ err_port_ets_init:
 err_port_buffers_init:
 err_port_admin_status_set:
 err_port_mtu_set:
-err_port_max_mtu_get:
 err_max_speed_get:
 err_port_speed_by_width_set:
 err_port_system_port_mapping_set:
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum.h b/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
index 3beb5d0847ab..bb0586b45c8d 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
@@ -359,7 +359,6 @@ struct mlxsw_sp_port {
 		u16 egr_types;
 		struct mlxsw_sp_ptp_port_stats stats;
 	} ptp;
-	int max_mtu;
 	u32 max_speed;
 	struct mlxsw_sp_hdroom *hdroom;
 	u64 module_overheat_initial_val;
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c
index c9f1c79f3f9d..1b9ed393fbd4 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_buffers.c
@@ -399,11 +399,13 @@ void mlxsw_sp_hdroom_bufs_reset_sizes(struct mlxsw_sp_port *mlxsw_sp_port,
 				      struct mlxsw_sp_hdroom *hdroom)
 {
 	struct mlxsw_sp *mlxsw_sp = mlxsw_sp_port->mlxsw_sp;
+	unsigned int max_mtu = mlxsw_sp_port->dev->max_mtu;
 	u16 reserve_cells;
 	int i;
 
+	max_mtu += MLXSW_PORT_ETH_FRAME_HDR;
 	/* Internal buffer. */
-	reserve_cells = mlxsw_sp_hdroom_int_buf_size_get(mlxsw_sp, mlxsw_sp_port->max_mtu,
+	reserve_cells = mlxsw_sp_hdroom_int_buf_size_get(mlxsw_sp, max_mtu,
 							 mlxsw_sp_port->max_speed);
 	reserve_cells = mlxsw_sp_port_headroom_8x_adjust(mlxsw_sp_port, reserve_cells);
 	hdroom->int_buf.reserve_cells = reserve_cells;
@@ -613,7 +615,9 @@ static int mlxsw_sp_port_headroom_init(struct mlxsw_sp_port *mlxsw_sp_port)
 	mlxsw_sp_hdroom_bufs_reset_sizes(mlxsw_sp_port, &hdroom);
 
 	/* Buffer 9 is used for control traffic. */
-	size9 = mlxsw_sp_port_headroom_8x_adjust(mlxsw_sp_port, mlxsw_sp_port->max_mtu);
+	size9 = mlxsw_sp_port_headroom_8x_adjust(mlxsw_sp_port,
+						 mlxsw_sp_port->dev->max_mtu +
+						 MLXSW_PORT_ETH_FRAME_HDR);
 	hdroom.bufs.buf[9].size_cells = mlxsw_sp_bytes_cells(mlxsw_sp, size9);
 
 	return __mlxsw_sp_hdroom_configure(mlxsw_sp_port, &hdroom, true);