mlxsw: spectrum_router: Add support for double entry RIFs

In Spectrum-1, loopback router interfaces (RIFs) used for IP-in-IP
encapsulation with an IPv6 underlay require two RIF entries and the RIF
index must be even.

Prepare for this change by extending the RIF parameters structure with a
'double_entry' field that indicates if the RIF being created requires
two RIF entries or not. Only set it for RIFs representing ip6gre tunnels
in Spectrum-1.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Amit Cohen <amcohen@nvidia.com>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/mellanox/mlxsw/spectrum_ipip.c

@@ -433,6 +433,7 @@ static const struct mlxsw_sp_ipip_ops mlxsw_sp1_ipip_gre6_ops = {
 	.dev_type = ARPHRD_IP6GRE,
 	.ul_proto = MLXSW_SP_L3_PROTO_IPV6,
 	.inc_parsing_depth = true,
+	.double_rif_entry = true,
 	.parms_init = mlxsw_sp1_ipip_netdev_parms_init_gre6,
 	.nexthop_update = mlxsw_sp1_ipip_nexthop_update_gre6,
 	.decap_config = mlxsw_sp1_ipip_decap_config_gre6,

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

@@ -49,6 +49,7 @@ struct mlxsw_sp_ipip_ops {
 	int dev_type;
 	enum mlxsw_sp_l3proto ul_proto; /* Underlay. */
 	bool inc_parsing_depth;
+	bool double_rif_entry;
 
 	struct mlxsw_sp_ipip_parms
 	(*parms_init)(const struct net_device *ol_dev);

drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c

@@ -79,6 +79,7 @@ struct mlxsw_sp_rif_params {
 	};
 	u16 vid;
 	bool lag;
+	bool double_entry;
 };
 
 struct mlxsw_sp_rif_subport {
@@ -1070,6 +1071,7 @@ mlxsw_sp_ipip_ol_ipip_lb_create(struct mlxsw_sp *mlxsw_sp,
 	lb_params = (struct mlxsw_sp_rif_params_ipip_lb) {
 		.common.dev = ol_dev,
 		.common.lag = false,
+		.common.double_entry = ipip_ops->double_rif_entry,
 		.lb_config = ipip_ops->ol_loopback_config(mlxsw_sp, ol_dev),
 	};
 
@@ -8091,13 +8093,13 @@ mlxsw_sp_rif_create(struct mlxsw_sp *mlxsw_sp,
 		    const struct mlxsw_sp_rif_params *params,
 		    struct netlink_ext_ack *extack)
 {
+	u8 rif_entries = params->double_entry ? 2 : 1;
 	u32 tb_id = l3mdev_fib_table(params->dev);
 	const struct mlxsw_sp_rif_ops *ops;
 	struct mlxsw_sp_fid *fid = NULL;
 	enum mlxsw_sp_rif_type type;
 	struct mlxsw_sp_rif *rif;
 	struct mlxsw_sp_vr *vr;
-	u8 rif_entries = 1;
 	u16 rif_index;
 	int i, err;