mlxsw: reg: Add support for ritr_loopback_ipip6_pack()

The RITR register is used to configure the router interface table.

For IP-in-IP, it stores the underlay source IP address for encapsulation
and also the ingress RIF for the underlay lookup.

Add support for IPv6 IP-in-IP configuration.
Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/reg.h

@@ -6734,6 +6734,23 @@ mlxsw_reg_ritr_loopback_ipip4_pack(char *payload,
 	mlxsw_reg_ritr_loopback_ipip_usip4_set(payload, usip);
 }
 
+static inline void
+mlxsw_reg_ritr_loopback_ipip6_pack(char *payload,
+				   enum mlxsw_reg_ritr_loopback_ipip_type ipip_type,
+				   enum mlxsw_reg_ritr_loopback_ipip_options options,
+				   u16 uvr_id, u16 underlay_rif,
+				   const struct in6_addr *usip, u32 gre_key)
+{
+	enum mlxsw_reg_ritr_loopback_protocol protocol =
+		MLXSW_REG_RITR_LOOPBACK_PROTOCOL_IPIP_IPV6;
+
+	mlxsw_reg_ritr_loopback_protocol_set(payload, protocol);
+	mlxsw_reg_ritr_loopback_ipip_common_pack(payload, ipip_type, options,
+						 uvr_id, underlay_rif, gre_key);
+	mlxsw_reg_ritr_loopback_ipip_usip6_memcpy_to(payload,
+						     (const char *)usip);
+}
+
 /* RTAR - Router TCAM Allocation Register
  * --------------------------------------
  * This register is used for allocation of regions in the TCAM table.