net/mlx5: Add MACsec offload Tx command support

This patch adds support for Connect-X MACsec offload Tx SA commands:
add, update and delete.

In Connect-X MACsec, a Security Association (SA) is added or deleted
via allocating a HW context of an encryption/decryption key and
a HW context of a matching SA (MACsec object).

When new SA is added:
- Use a separate crypto key HW context.
- Create a separate MACsec context in HW to include the SA properties.

Introduce a new compilation flag MLX5_EN_MACSEC for it.

Follow-up patches will implement the Tx steering.

Signed-off-by: Lior Nahmanson <liorna@nvidia.com>
Reviewed-by: Raed Salem <raeds@nvidia.com>
Signed-off-by: Raed Salem <raeds@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlx5/core/Kconfig

@@ -139,6 +139,14 @@ config MLX5_CORE_IPOIB
 	help
 	  MLX5 IPoIB offloads & acceleration support.
 
+config MLX5_EN_MACSEC
+	bool "Connect-X support for MACSec offload"
+	depends on MLX5_CORE_EN
+	depends on MACSEC
+	default n
+	help
+	  Build support for MACsec cryptography-offload acceleration in the NIC.
+
 config MLX5_EN_IPSEC
 	bool "Mellanox Technologies IPsec Connect-X support"
 	depends on MLX5_CORE_EN

drivers/net/ethernet/mellanox/mlx5/core/Makefile

@@ -92,6 +92,8 @@ mlx5_core-$(CONFIG_MLX5_CORE_IPOIB) += ipoib/ipoib.o ipoib/ethtool.o ipoib/ipoib
 #
 mlx5_core-$(CONFIG_MLX5_FPGA) += fpga/cmd.o fpga/core.o fpga/conn.o fpga/sdk.o
 
+mlx5_core-$(CONFIG_MLX5_EN_MACSEC) += en_accel/macsec.o
+
 mlx5_core-$(CONFIG_MLX5_EN_IPSEC) += en_accel/ipsec.o en_accel/ipsec_rxtx.o \
 				     en_accel/ipsec_stats.o en_accel/ipsec_fs.o \
 				     en_accel/ipsec_offload.o

drivers/net/ethernet/mellanox/mlx5/core/en.h

@@ -954,6 +954,9 @@ struct mlx5e_priv {
 
 	const struct mlx5e_profile *profile;
 	void                      *ppriv;
+#ifdef CONFIG_MLX5_EN_MACSEC
+	struct mlx5e_macsec       *macsec;
+#endif
 #ifdef CONFIG_MLX5_EN_IPSEC
 	struct mlx5e_ipsec        *ipsec;
 #endif