dpaa2-eth: use the DPMAC id as the devlink physical port number

dpaa2-eth registers every DPNI as a devlink port of flavour physical
without setting a port number. All DPAA2 interfaces report the same
phys_port_name, p0 (see devlink port show).

The DPNI endpoint can change at runtime while the attributes of a
registered devlink port cannot, so log a warning when it happens.

Another benefit: udev rules can match ATTR{phys_port_name} to name an
interface based on its DPMAC.

Signed-off-by: Vincent Jardin <vjardin@free.fr>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260928-for-upstream-dpaa2_ports-v2-1-1cda148530bf@free.fr
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

3 files changed, 44 insertions, 1 deletions

diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth-devlink.c b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth-devlink.c
index 8775c931106b..4c0a04c2d458 100644
--- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth-devlink.c
+++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth-devlink.c
@@ -213,20 +213,58 @@ void dpaa2_eth_dl_unregister(struct dpaa2_eth_priv *priv)
 	devlink_unregister(priv->devlink);
 }
 
+static u32 dpaa2_eth_dl_port_number(struct dpaa2_eth_priv *priv)
+{
+	lockdep_assert_held(&priv->mac_lock);
+
+	return dpaa2_eth_has_mac(priv) ? priv->mac->mc_dev->obj_desc.id : 0;
+}
+
 int dpaa2_eth_dl_port_add(struct dpaa2_eth_priv *priv)
 {
 	struct devlink_port *devlink_port = &priv->devlink_port;
 	struct devlink_port_attrs attrs = {};
+	u32 port_number;
+	int err;
+
+	mutex_lock(&priv->mac_lock);
+	port_number = dpaa2_eth_dl_port_number(priv);
+	priv->dl_port_number = port_number;
+	priv->dl_port_valid = true;
+	mutex_unlock(&priv->mac_lock);
 
 	attrs.flavour = DEVLINK_PORT_FLAVOUR_PHYSICAL;
+	attrs.phys.port_number = port_number;
 	devlink_port_attrs_set(devlink_port, &attrs);
-	return devlink_port_register(priv->devlink, devlink_port, 0);
+	err = devlink_port_register(priv->devlink, devlink_port, 0);
+	if (err) {
+		mutex_lock(&priv->mac_lock);
+		priv->dl_port_valid = false;
+		mutex_unlock(&priv->mac_lock);
+	}
+
+	return err;
+}
+
+void dpaa2_eth_dl_port_check(struct dpaa2_eth_priv *priv)
+{
+	mutex_lock(&priv->mac_lock);
+	if (priv->dl_port_valid &&
+	    priv->dl_port_number != dpaa2_eth_dl_port_number(priv))
+		netdev_warn(priv->net_dev,
+			    "devlink port number %u is stale, rebind to update\n",
+			    priv->dl_port_number);
+	mutex_unlock(&priv->mac_lock);
 }
 
 void dpaa2_eth_dl_port_del(struct dpaa2_eth_priv *priv)
 {
 	struct devlink_port *devlink_port = &priv->devlink_port;
 
+	mutex_lock(&priv->mac_lock);
+	priv->dl_port_valid = false;
+	mutex_unlock(&priv->mac_lock);
+
 	devlink_port_unregister(devlink_port);
 }
 
diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
index 6f1046c9cc51..def2d5c0e7f7 100644
--- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
+++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
@@ -4771,6 +4771,8 @@ static irqreturn_t dpni_irq0_handler_thread(int irq_num, void *arg)
 			dpaa2_eth_disconnect_mac(priv);
 		else
 			dpaa2_eth_connect_mac(priv);
+
+		dpaa2_eth_dl_port_check(priv);
 	}
 
 	return IRQ_HANDLED;
diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.h b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.h
index 834cba8c3a41..3e0acd15549e 100644
--- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.h
+++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.h
@@ -632,6 +632,8 @@ struct dpaa2_eth_priv {
 	struct devlink *devlink;
 	struct dpaa2_eth_trap_data *trap_data;
 	struct devlink_port devlink_port;
+	u32 dl_port_number;
+	bool dl_port_valid;
 
 	u32 rx_copybreak;
 
@@ -802,6 +804,7 @@ void dpaa2_eth_dl_unregister(struct dpaa2_eth_priv *priv);
 
 int dpaa2_eth_dl_port_add(struct dpaa2_eth_priv *priv);
 void dpaa2_eth_dl_port_del(struct dpaa2_eth_priv *priv);
+void dpaa2_eth_dl_port_check(struct dpaa2_eth_priv *priv);
 
 int dpaa2_eth_dl_traps_register(struct dpaa2_eth_priv *priv);
 void dpaa2_eth_dl_traps_unregister(struct dpaa2_eth_priv *priv);