net/mlx4_en: Add HW timestamping (TS) support

The patch allows to enable/disable HW timestamping for incoming and/or
outgoing packets. It adds and initializes all structs and callbacks
needed by kernel TS API.
To enable/disable HW timestamping appropriate ioctl should be used.
Currently HWTSTAMP_FILTER_ALL/NONE and HWTSAMP_TX_ON/OFF only are
supported.
When enabling TS on receive flow - VLAN stripping will be disabled.
Also were made all relevant changes in RX/TX flows to consider TS request
and plant HW timestamps into relevant structures.
mlx4_ib was fixed to compile with new mlx4_cq_alloc() signature.

Signed-off-by: Eugenia Emantayev <eugenia@mellanox.com>
Signed-off-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/mlx4/cq.h b/include/linux/mlx4/cq.h
index 6f65b2c..98fa492 100644
--- a/include/linux/mlx4/cq.h
+++ b/include/linux/mlx4/cq.h
@@ -64,6 +64,22 @@
 	u8			owner_sr_opcode;
 };
 
+struct mlx4_ts_cqe {
+	__be32			vlan_my_qpn;
+	__be32			immed_rss_invalid;
+	__be32			g_mlpath_rqpn;
+	__be32			timestamp_hi;
+	__be16			status;
+	u8			ipv6_ext_mask;
+	u8			badfcs_enc;
+	__be32			byte_cnt;
+	__be16			wqe_index;
+	__be16			checksum;
+	u8			reserved;
+	__be16			timestamp_lo;
+	u8			owner_sr_opcode;
+} __packed;
+
 enum {
 	MLX4_CQE_VLAN_PRESENT_MASK	= 1 << 29,
 	MLX4_CQE_QPN_MASK		= 0xffffff,