net/mlx4_core: Configure mlx4 hardware for mixed RoCE v1/v2 modes

If the hardware supports RoCE v2 (mixed with RoCE v1) mode, we enable
it. This is necessary in order to support RoCE v2.
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

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

@@ -778,7 +778,10 @@ struct mlx4_set_port_general_context {
 	u16 reserved1;
 	u8 v_ignore_fcs;
 	u8 flags;
-	u8 ignore_fcs;
+	union {
+		u8 ignore_fcs;
+		u8 roce_mode;
+	};
 	u8 reserved2;
 	__be16 mtu;
 	u8 pptx;

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

@@ -968,6 +968,8 @@ int mlx4_SET_PORT(struct mlx4_dev *dev, u8 port, int pkey_tbl_sz)
 	return err;
 }
 
+#define SET_PORT_ROCE_2_FLAGS          0x10
+#define MLX4_SET_PORT_ROCE_V1_V2       0x2
 int mlx4_SET_PORT_general(struct mlx4_dev *dev, u8 port, int mtu,
 			  u8 pptx, u8 pfctx, u8 pprx, u8 pfcrx)
 {
@@ -987,6 +989,11 @@ int mlx4_SET_PORT_general(struct mlx4_dev *dev, u8 port, int mtu,
 	context->pprx = (pprx * (!pfcrx)) << 7;
 	context->pfcrx = pfcrx;
 
+	if (dev->caps.flags2 & MLX4_DEV_CAP_FLAG2_ROCE_V1_V2) {
+		context->flags |= SET_PORT_ROCE_2_FLAGS;
+		context->roce_mode |=
+			MLX4_SET_PORT_ROCE_V1_V2 << 4;
+	}
 	in_mod = MLX4_SET_PORT_GENERAL << 8 | port;
 	err = mlx4_cmd(dev, mailbox->dma, in_mod, MLX4_SET_PORT_ETH_OPCODE,
 		       MLX4_CMD_SET_PORT, MLX4_CMD_TIME_CLASS_B,