Merge branch 'net-extend-devlink-port-attrs-with-switch-ID'

Jiri Pirko says:

====================
net: extend devlink port attrs with switch ID

Extend devlink port attrs to contain switch ID and change drivers that
register devlink ports to use that.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/bnxt/bnxt.c

@@ -10104,7 +10104,6 @@ static const struct net_device_ops bnxt_netdev_ops = {
 	.ndo_bpf		= bnxt_xdp,
 	.ndo_bridge_getlink	= bnxt_bridge_getlink,
 	.ndo_bridge_setlink	= bnxt_bridge_setlink,
-	.ndo_get_port_parent_id	= bnxt_get_port_parent_id,
 	.ndo_get_devlink_port	= bnxt_get_devlink_port,
 };
 
@@ -10429,6 +10428,26 @@ static int bnxt_init_mac_addr(struct bnxt *bp)
 	return rc;
 }
 
+static int bnxt_pcie_dsn_get(struct bnxt *bp, u8 dsn[])
+{
+	struct pci_dev *pdev = bp->pdev;
+	int pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_DSN);
+	u32 dw;
+
+	if (!pos) {
+		netdev_info(bp->dev, "Unable do read adapter's DSN");
+		return -EOPNOTSUPP;
+	}
+
+	/* DSN (two dw) is at an offset of 4 from the cap pos */
+	pos += 4;
+	pci_read_config_dword(pdev, pos, &dw);
+	put_unaligned_le32(dw, &dsn[0]);
+	pci_read_config_dword(pdev, pos + 4, &dw);
+	put_unaligned_le32(dw, &dsn[4]);
+	return 0;
+}
+
 static int bnxt_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 {
 	static int version_printed;
@@ -10569,6 +10588,11 @@ static int bnxt_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 		goto init_err_pci_clean;
 	}
 
+	/* Read the adapter's DSN to use as the eswitch switch_id */
+	rc = bnxt_pcie_dsn_get(bp, bp->switch_id);
+	if (rc)
+		goto init_err_pci_clean;
+
 	bnxt_hwrm_func_qcfg(bp);
 	bnxt_hwrm_vnic_qcaps(bp);
 	bnxt_hwrm_port_led_qcaps(bp);

drivers/net/ethernet/broadcom/bnxt/bnxt_devlink.c

@@ -230,7 +230,8 @@ int bnxt_dl_register(struct bnxt *bp)
 	}
 
 	devlink_port_attrs_set(&bp->dl_port, DEVLINK_PORT_FLAVOUR_PHYSICAL,
-			       bp->pf.port_id, false, 0);
+			       bp->pf.port_id, false, 0,
+			       bp->switch_id, sizeof(bp->switch_id));
 	rc = devlink_port_register(dl, &bp->dl_port, bp->pf.port_id);
 	if (rc) {
 		netdev_err(bp->dev, "devlink_port_register failed");

drivers/net/ethernet/broadcom/bnxt/bnxt_vfr.c

@@ -406,26 +406,6 @@ static void bnxt_vf_rep_netdev_init(struct bnxt *bp, struct bnxt_vf_rep *vf_rep,
 	dev->min_mtu = ETH_ZLEN;
 }
 
-static int bnxt_pcie_dsn_get(struct bnxt *bp, u8 dsn[])
-{
-	struct pci_dev *pdev = bp->pdev;
-	int pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_DSN);
-	u32 dw;
-
-	if (!pos) {
-		netdev_info(bp->dev, "Unable do read adapter's DSN");
-		return -EOPNOTSUPP;
-	}
-
-	/* DSN (two dw) is at an offset of 4 from the cap pos */
-	pos += 4;
-	pci_read_config_dword(pdev, pos, &dw);
-	put_unaligned_le32(dw, &dsn[0]);
-	pci_read_config_dword(pdev, pos + 4, &dw);
-	put_unaligned_le32(dw, &dsn[4]);
-	return 0;
-}
-
 static int bnxt_vf_reps_create(struct bnxt *bp)
 {
 	u16 *cfa_code_map = NULL, num_vfs = pci_num_vf(bp->pdev);
@@ -490,11 +470,6 @@ static int bnxt_vf_reps_create(struct bnxt *bp)
 		}
 	}
 
-	/* Read the adapter's DSN to use as the eswitch switch_id */
-	rc = bnxt_pcie_dsn_get(bp, bp->switch_id);
-	if (rc)
-		goto err;
-
 	/* publish cfa_code_map only after all VF-reps have been initialized */
 	bp->cfa_code_map = cfa_code_map;
 	bp->eswitch_mode = DEVLINK_ESWITCH_MODE_SWITCHDEV;

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

@@ -1720,7 +1720,9 @@ EXPORT_SYMBOL(mlxsw_core_res_get);
 
 int mlxsw_core_port_init(struct mlxsw_core *mlxsw_core, u8 local_port,
 			 u32 port_number, bool split,
-			 u32 split_port_subnumber)
+			 u32 split_port_subnumber,
+			 const unsigned char *switch_id,
+			 unsigned char switch_id_len)
 {
 	struct devlink *devlink = priv_to_devlink(mlxsw_core);
 	struct mlxsw_core_port *mlxsw_core_port =
@@ -1730,7 +1732,8 @@ int mlxsw_core_port_init(struct mlxsw_core *mlxsw_core, u8 local_port,
 
 	mlxsw_core_port->local_port = local_port;
 	devlink_port_attrs_set(devlink_port, DEVLINK_PORT_FLAVOUR_PHYSICAL,
-			       port_number, split, split_port_subnumber);
+			       port_number, split, split_port_subnumber,
+			       switch_id, switch_id_len);
 	err = devlink_port_register(devlink, devlink_port, local_port);
 	if (err)
 		memset(mlxsw_core_port, 0, sizeof(*mlxsw_core_port));

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

@@ -166,7 +166,9 @@ void mlxsw_core_lag_mapping_clear(struct mlxsw_core *mlxsw_core,
 void *mlxsw_core_port_driver_priv(struct mlxsw_core_port *mlxsw_core_port);
 int mlxsw_core_port_init(struct mlxsw_core *mlxsw_core, u8 local_port,
 			 u32 port_number, bool split,
-			 u32 split_port_subnumber);
+			 u32 split_port_subnumber,
+			 const unsigned char *switch_id,
+			 unsigned char switch_id_len);
 void mlxsw_core_port_fini(struct mlxsw_core *mlxsw_core, u8 local_port);
 void mlxsw_core_port_eth_set(struct mlxsw_core *mlxsw_core, u8 local_port,
 			     void *port_driver_priv, struct net_device *dev);

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

@@ -51,18 +51,6 @@ static int mlxsw_m_port_dummy_open_stop(struct net_device *dev)
 	return 0;
 }
 
-static int mlxsw_m_port_get_port_parent_id(struct net_device *dev,
-					   struct netdev_phys_item_id *ppid)
-{
-	struct mlxsw_m_port *mlxsw_m_port = netdev_priv(dev);
-	struct mlxsw_m *mlxsw_m = mlxsw_m_port->mlxsw_m;
-
-	ppid->id_len = sizeof(mlxsw_m->base_mac);
-	memcpy(&ppid->id, &mlxsw_m->base_mac, ppid->id_len);
-
-	return 0;
-}
-
 static struct devlink_port *
 mlxsw_m_port_get_devlink_port(struct net_device *dev)
 {
@@ -76,7 +64,6 @@ mlxsw_m_port_get_devlink_port(struct net_device *dev)
 static const struct net_device_ops mlxsw_m_port_netdev_ops = {
 	.ndo_open		= mlxsw_m_port_dummy_open_stop,
 	.ndo_stop		= mlxsw_m_port_dummy_open_stop,
-	.ndo_get_port_parent_id	= mlxsw_m_port_get_port_parent_id,
 	.ndo_get_devlink_port	= mlxsw_m_port_get_devlink_port,
 };
 
@@ -151,7 +138,9 @@ mlxsw_m_port_create(struct mlxsw_m *mlxsw_m, u8 local_port, u8 module)
 	int err;
 
 	err = mlxsw_core_port_init(mlxsw_m->core, local_port,
-				   module + 1, false, 0);
+				   module + 1, false, 0,
+				   mlxsw_m->base_mac,
+				   sizeof(mlxsw_m->base_mac));
 	if (err) {
 		dev_err(mlxsw_m->bus_info->dev, "Port %d: Failed to init core port\n",
 			local_port);

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

@@ -1704,18 +1704,6 @@ static int mlxsw_sp_set_features(struct net_device *dev,
 				       mlxsw_sp_feature_hw_tc);
 }
 
-static int mlxsw_sp_port_get_port_parent_id(struct net_device *dev,
-					    struct netdev_phys_item_id *ppid)
-{
-	struct mlxsw_sp_port *mlxsw_sp_port = netdev_priv(dev);
-	struct mlxsw_sp *mlxsw_sp = mlxsw_sp_port->mlxsw_sp;
-
-	ppid->id_len = sizeof(mlxsw_sp->base_mac);
-	memcpy(&ppid->id, &mlxsw_sp->base_mac, ppid->id_len);
-
-	return 0;
-}
-
 static struct devlink_port *
 mlxsw_sp_port_get_devlink_port(struct net_device *dev)
 {
@@ -1740,7 +1728,6 @@ static const struct net_device_ops mlxsw_sp_port_netdev_ops = {
 	.ndo_vlan_rx_add_vid	= mlxsw_sp_port_add_vid,
 	.ndo_vlan_rx_kill_vid	= mlxsw_sp_port_kill_vid,
 	.ndo_set_features	= mlxsw_sp_set_features,
-	.ndo_get_port_parent_id	= mlxsw_sp_port_get_port_parent_id,
 	.ndo_get_devlink_port	= mlxsw_sp_port_get_devlink_port,
 };
 
@@ -3392,7 +3379,9 @@ static int mlxsw_sp_port_create(struct mlxsw_sp *mlxsw_sp, u8 local_port,
 	int err;
 
 	err = mlxsw_core_port_init(mlxsw_sp->core, local_port,
-				   module + 1, split, lane / width);
+				   module + 1, split, lane / width,
+				   mlxsw_sp->base_mac,
+				   sizeof(mlxsw_sp->base_mac));
 	if (err) {
 		dev_err(mlxsw_sp->bus_info->dev, "Port %d: Failed to init core port\n",
 			local_port);

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

@@ -30,6 +30,7 @@ struct mlxsw_sib {
 	struct mlxsw_sib_port **ports;
 	struct mlxsw_core *core;
 	const struct mlxsw_bus_info *bus_info;
+	u8 hw_id[ETH_ALEN];
 };
 
 struct mlxsw_sib_port {
@@ -102,6 +103,18 @@ mlxsw_sib_tx_v1_hdr_construct(struct sk_buff *skb,
 	mlxsw_tx_v1_hdr_type_set(txhdr, MLXSW_TXHDR_TYPE_CONTROL);
 }
 
+static int mlxsw_sib_hw_id_get(struct mlxsw_sib *mlxsw_sib)
+{
+	char spad_pl[MLXSW_REG_SPAD_LEN] = {0};
+	int err;
+
+	err = mlxsw_reg_query(mlxsw_sib->core, MLXSW_REG(spad), spad_pl);
+	if (err)
+		return err;
+	mlxsw_reg_spad_base_mac_memcpy_from(spad_pl, mlxsw_sib->hw_id);
+	return 0;
+}
+
 static int
 mlxsw_sib_port_admin_status_set(struct mlxsw_sib_port *mlxsw_sib_port,
 				bool is_up)
@@ -268,7 +281,8 @@ static int mlxsw_sib_port_create(struct mlxsw_sib *mlxsw_sib, u8 local_port,
 	int err;
 
 	err = mlxsw_core_port_init(mlxsw_sib->core, local_port,
-				   module + 1, false, 0);
+				   module + 1, false, 0,
+				   mlxsw_sib->hw_id, sizeof(mlxsw_sib->hw_id));
 	if (err) {
 		dev_err(mlxsw_sib->bus_info->dev, "Port %d: Failed to init core port\n",
 			local_port);
@@ -440,6 +454,12 @@ static int mlxsw_sib_init(struct mlxsw_core *mlxsw_core,
 	mlxsw_sib->core = mlxsw_core;
 	mlxsw_sib->bus_info = mlxsw_bus_info;
 
+	err = mlxsw_sib_hw_id_get(mlxsw_sib);
+	if (err) {
+		dev_err(mlxsw_sib->bus_info->dev, "Failed to get switch HW ID\n");
+		return err;
+	}
+
 	err = mlxsw_sib_ports_create(mlxsw_sib);
 	if (err) {
 		dev_err(mlxsw_sib->bus_info->dev, "Failed to create ports\n");

drivers/net/ethernet/mellanox/mlxsw/switchx2.c

@@ -379,18 +379,6 @@ mlxsw_sx_port_get_stats64(struct net_device *dev,
 	stats->tx_dropped	= tx_dropped;
 }
 
-static int mlxsw_sx_port_get_port_parent_id(struct net_device *dev,
-					    struct netdev_phys_item_id *ppid)
-{
-	struct mlxsw_sx_port *mlxsw_sx_port = netdev_priv(dev);
-	struct mlxsw_sx *mlxsw_sx = mlxsw_sx_port->mlxsw_sx;
-
-	ppid->id_len = sizeof(mlxsw_sx->hw_id);
-	memcpy(&ppid->id, &mlxsw_sx->hw_id, ppid->id_len);
-
-	return 0;
-}
-
 static struct devlink_port *
 mlxsw_sx_port_get_devlink_port(struct net_device *dev)
 {
@@ -407,7 +395,6 @@ static const struct net_device_ops mlxsw_sx_port_netdev_ops = {
 	.ndo_start_xmit		= mlxsw_sx_port_xmit,
 	.ndo_change_mtu		= mlxsw_sx_port_change_mtu,
 	.ndo_get_stats64	= mlxsw_sx_port_get_stats64,
-	.ndo_get_port_parent_id	= mlxsw_sx_port_get_port_parent_id,
 	.ndo_get_devlink_port	= mlxsw_sx_port_get_devlink_port,
 };
 
@@ -1128,7 +1115,8 @@ static int mlxsw_sx_port_eth_create(struct mlxsw_sx *mlxsw_sx, u8 local_port,
 	int err;
 
 	err = mlxsw_core_port_init(mlxsw_sx->core, local_port,
-				   module + 1, false, 0);
+				   module + 1, false, 0,
+				   mlxsw_sx->hw_id, sizeof(mlxsw_sx->hw_id));
 	if (err) {
 		dev_err(mlxsw_sx->bus_info->dev, "Port %d: Failed to init core port\n",
 			local_port);

drivers/net/ethernet/netronome/nfp/nfp_devlink.c

@@ -354,6 +354,8 @@ int nfp_devlink_port_register(struct nfp_app *app, struct nfp_port *port)
 {
 	struct nfp_eth_table_port eth_port;
 	struct devlink *devlink;
+	const u8 *serial;
+	int serial_len;
 	int ret;
 
 	rtnl_lock();
@@ -362,9 +364,10 @@ int nfp_devlink_port_register(struct nfp_app *app, struct nfp_port *port)
 	if (ret)
 		return ret;
 
+	serial_len = nfp_cpp_serial(port->app->cpp, &serial);
 	devlink_port_attrs_set(&port->dl_port, DEVLINK_PORT_FLAVOUR_PHYSICAL,
 			       eth_port.label_port, eth_port.is_split,
-			       eth_port.label_subport);
+			       eth_port.label_subport, serial, serial_len);
 
 	devlink = priv_to_devlink(app->pf);
 

drivers/net/ethernet/netronome/nfp/nfp_net_common.c

@@ -3533,7 +3533,6 @@ const struct net_device_ops nfp_net_netdev_ops = {
 	.ndo_udp_tunnel_add	= nfp_net_add_vxlan_port,
 	.ndo_udp_tunnel_del	= nfp_net_del_vxlan_port,
 	.ndo_bpf		= nfp_net_xdp,
-	.ndo_get_port_parent_id	= nfp_port_get_port_parent_id,
 	.ndo_get_devlink_port	= nfp_devlink_get_devlink_port,
 };
 

drivers/net/ethernet/netronome/nfp/nfp_net_repr.c

@@ -272,7 +272,6 @@ const struct net_device_ops nfp_repr_netdev_ops = {
 	.ndo_fix_features	= nfp_repr_fix_features,
 	.ndo_set_features	= nfp_port_set_features,
 	.ndo_set_mac_address    = eth_mac_addr,
-	.ndo_get_port_parent_id	= nfp_port_get_port_parent_id,
 	.ndo_get_devlink_port	= nfp_devlink_get_devlink_port,
 };
 

drivers/net/ethernet/netronome/nfp/nfp_port.c

@@ -30,22 +30,6 @@ struct nfp_port *nfp_port_from_netdev(struct net_device *netdev)
 	return NULL;
 }
 
-int nfp_port_get_port_parent_id(struct net_device *netdev,
-				struct netdev_phys_item_id *ppid)
-{
-	struct nfp_port *port;
-	const u8 *serial;
-
-	port = nfp_port_from_netdev(netdev);
-	if (!port)
-		return -EOPNOTSUPP;
-
-	ppid->id_len = nfp_cpp_serial(port->app->cpp, &serial);
-	memcpy(&ppid->id, serial, ppid->id_len);
-
-	return 0;
-}
-
 int nfp_port_setup_tc(struct net_device *netdev, enum tc_setup_type type,
 		      void *type_data)
 {

include/net/devlink.h

@@ -41,11 +41,13 @@ struct devlink {
 };
 
 struct devlink_port_attrs {
-	bool set;
+	u8 set:1,
+	   split:1,
+	   switch_port:1;
 	enum devlink_port_flavour flavour;
 	u32 port_number; /* same value as "split group" */
-	bool split;
 	u32 split_subport_number;
+	struct netdev_phys_item_id switch_id;
 };
 
 struct devlink_port {
@@ -582,7 +584,9 @@ void devlink_port_type_clear(struct devlink_port *devlink_port);
 void devlink_port_attrs_set(struct devlink_port *devlink_port,
 			    enum devlink_port_flavour flavour,
 			    u32 port_number, bool split,
-			    u32 split_subport_number);
+			    u32 split_subport_number,
+			    const unsigned char *switch_id,
+			    unsigned char switch_id_len);
 int devlink_sb_register(struct devlink *devlink, unsigned int sb_index,
 			u32 size, u16 ingress_pools_count,
 			u16 egress_pools_count, u16 ingress_tc_count,
@@ -739,6 +743,8 @@ void devlink_compat_running_version(struct net_device *dev,
 int devlink_compat_flash_update(struct net_device *dev, const char *file_name);
 int devlink_compat_phys_port_name_get(struct net_device *dev,
 				      char *name, size_t len);
+int devlink_compat_switch_id_get(struct net_device *dev,
+				 struct netdev_phys_item_id *ppid);
 
 #else
 
@@ -760,6 +766,13 @@ devlink_compat_phys_port_name_get(struct net_device *dev,
 	return -EOPNOTSUPP;
 }
 
+static inline int
+devlink_compat_switch_id_get(struct net_device *dev,
+			     struct netdev_phys_item_id *ppid)
+{
+	return -EOPNOTSUPP;
+}
+
 #endif
 
 #endif /* _NET_DEVLINK_H_ */

net/core/dev.c

@@ -7900,13 +7900,20 @@ int dev_get_port_parent_id(struct net_device *dev,
 	struct netdev_phys_item_id first = { };
 	struct net_device *lower_dev;
 	struct list_head *iter;
-	int err = -EOPNOTSUPP;
+	int err;
+
+	if (ops->ndo_get_port_parent_id) {
+		err = ops->ndo_get_port_parent_id(dev, ppid);
+		if (err != -EOPNOTSUPP)
+			return err;
+	}
 
-	if (ops->ndo_get_port_parent_id)
-		return ops->ndo_get_port_parent_id(dev, ppid);
+	err = devlink_compat_switch_id_get(dev, ppid);
+	if (!err || err != -EOPNOTSUPP)
+		return err;
 
 	if (!recurse)
-		return err;
+		return -EOPNOTSUPP;
 
 	netdev_for_each_lower_dev(dev, lower_dev, iter) {
 		err = dev_get_port_parent_id(lower_dev, ppid, recurse);

net/core/devlink.c

@@ -5358,24 +5358,38 @@ static void __devlink_port_type_set(struct devlink_port *devlink_port,
 void devlink_port_type_eth_set(struct devlink_port *devlink_port,
 			       struct net_device *netdev)
 {
+	const struct net_device_ops *ops = netdev->netdev_ops;
+
 	/* If driver registers devlink port, it should set devlink port
 	 * attributes accordingly so the compat functions are called
 	 * and the original ops are not used.
 	 */
-	if (netdev->netdev_ops->ndo_get_phys_port_name) {
+	if (ops->ndo_get_phys_port_name) {
 		/* Some drivers use the same set of ndos for netdevs
 		 * that have devlink_port registered and also for
 		 * those who don't. Make sure that ndo_get_phys_port_name
 		 * returns -EOPNOTSUPP here in case it is defined.
 		 * Warn if not.
 		 */
-		const struct net_device_ops *ops = netdev->netdev_ops;
 		char name[IFNAMSIZ];
 		int err;
 
 		err = ops->ndo_get_phys_port_name(netdev, name, sizeof(name));
 		WARN_ON(err != -EOPNOTSUPP);
 	}
+	if (ops->ndo_get_port_parent_id) {
+		/* Some drivers use the same set of ndos for netdevs
+		 * that have devlink_port registered and also for
+		 * those who don't. Make sure that ndo_get_port_parent_id
+		 * returns -EOPNOTSUPP here in case it is defined.
+		 * Warn if not.
+		 */
+		struct netdev_phys_item_id ppid;
+		int err;
+
+		err = ops->ndo_get_port_parent_id(netdev, &ppid);
+		WARN_ON(err != -EOPNOTSUPP);
+	}
 	__devlink_port_type_set(devlink_port, DEVLINK_PORT_TYPE_ETH, netdev);
 }
 EXPORT_SYMBOL_GPL(devlink_port_type_eth_set);
@@ -5414,11 +5428,16 @@ EXPORT_SYMBOL_GPL(devlink_port_type_clear);
  *	@split: indicates if this is split port
  *	@split_subport_number: if the port is split, this is the number
  *	                       of subport.
+ *	@switch_id: if the port is part of switch, this is buffer with ID,
+ *	            otwerwise this is NULL
+ *	@switch_id_len: length of the switch_id buffer
  */
 void devlink_port_attrs_set(struct devlink_port *devlink_port,
 			    enum devlink_port_flavour flavour,
 			    u32 port_number, bool split,
-			    u32 split_subport_number)
+			    u32 split_subport_number,
+			    const unsigned char *switch_id,
+			    unsigned char switch_id_len)
 {
 	struct devlink_port_attrs *attrs = &devlink_port->attrs;
 
@@ -5429,6 +5448,15 @@ void devlink_port_attrs_set(struct devlink_port *devlink_port,
 	attrs->port_number = port_number;
 	attrs->split = split;
 	attrs->split_subport_number = split_subport_number;
+	if (switch_id) {
+		attrs->switch_port = true;
+		if (WARN_ON(switch_id_len > MAX_PHYS_ITEM_ID_LEN))
+			switch_id_len = MAX_PHYS_ITEM_ID_LEN;
+		memcpy(attrs->switch_id.id, switch_id, switch_id_len);
+		attrs->switch_id.id_len = switch_id_len;
+	} else {
+		attrs->switch_port = false;
+	}
 }
 EXPORT_SYMBOL_GPL(devlink_port_attrs_set);
 
@@ -6494,6 +6522,25 @@ int devlink_compat_phys_port_name_get(struct net_device *dev,
 	return __devlink_port_phys_port_name_get(devlink_port, name, len);
 }
 
+int devlink_compat_switch_id_get(struct net_device *dev,
+				 struct netdev_phys_item_id *ppid)
+{
+	struct devlink_port *devlink_port;
+
+	/* RTNL mutex is held here which ensures that devlink_port
+	 * instance cannot disappear in the middle. No need to take
+	 * any devlink lock as only permanent values are accessed.
+	 */
+	ASSERT_RTNL();
+	devlink_port = netdev_to_devlink_port(dev);
+	if (!devlink_port || !devlink_port->attrs.switch_port)
+		return -EOPNOTSUPP;
+
+	memcpy(ppid, &devlink_port->attrs.switch_id, sizeof(*ppid));
+
+	return 0;
+}
+
 static int __init devlink_init(void)
 {
 	return genl_register_family(&devlink_nl_family);

net/dsa/dsa2.c

@@ -260,6 +260,7 @@ static int dsa_port_setup(struct dsa_port *dp)
 {
 	enum devlink_port_flavour flavour;
 	struct dsa_switch *ds = dp->ds;
+	struct dsa_switch_tree *dst = ds->dst;
 	int err;
 
 	if (dp->type == DSA_PORT_TYPE_UNUSED)
@@ -286,7 +287,8 @@ static int dsa_port_setup(struct dsa_port *dp)
 	 * independent from front panel port numbers.
 	 */
 	devlink_port_attrs_set(&dp->devlink_port, flavour,
-			       dp->index, false, 0);
+			       dp->index, false, 0,
+			       (const char *) &dst->index, sizeof(dst->index));
 	err = devlink_port_register(ds->devlink, &dp->devlink_port,
 				    dp->index);
 	if (err)

net/dsa/slave.c

@@ -379,6 +379,13 @@ static int dsa_slave_get_port_parent_id(struct net_device *dev,
 	struct dsa_switch *ds = dp->ds;
 	struct dsa_switch_tree *dst = ds->dst;
 
+	/* For non-legacy ports, devlink is used and it takes
+	 * care of the name generation. This ndo implementation
+	 * should be removed with legacy support.
+	 */
+	if (dp->ds->devlink)
+		return -EOPNOTSUPP;
+
 	ppid->id_len = sizeof(dst->index);
 	memcpy(&ppid->id, &dst->index, ppid->id_len);