net: sparx5: use is_port_rgmii() throughout

Now that we can check if a given port is an RGMII port, use it in the
following cases:

 - To set RGMII PHY modes for RGMII port devices.

 - To avoid checking for a SerDes node in the devicetree, when the port
   is an RGMII port.

 - To bail out of sparx5_port_init() when the common configuration is
   done.

Reviewed-by: Steen Hegelund <Steen.Hegelund@microchip.com>
Reviewed-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Tested-by: Robert Marko <robert.marko@sartura.hr>
Signed-off-by: Daniel Machon <daniel.machon@microchip.com>
Link: https://patch.msgid.link/20241220-sparx5-lan969x-switch-driver-4-v5-3-fa8ba5dff732@microchip.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/microchip/sparx5/sparx5_main.c

@@ -313,10 +313,13 @@ static int sparx5_create_port(struct sparx5 *sparx5,
 			      struct initial_port_config *config)
 {
 	struct sparx5_port *spx5_port;
+	const struct sparx5_ops *ops;
 	struct net_device *ndev;
 	struct phylink *phylink;
 	int err;
 
+	ops = sparx5->data->ops;
+
 	ndev = sparx5_create_netdev(sparx5, config->portno);
 	if (IS_ERR(ndev)) {
 		dev_err(sparx5->dev, "Could not create net device: %02u\n",
@@ -357,6 +360,9 @@ static int sparx5_create_port(struct sparx5 *sparx5,
 		MAC_SYM_PAUSE | MAC_10 | MAC_100 | MAC_1000FD |
 		MAC_2500FD | MAC_5000FD | MAC_10000FD | MAC_25000FD;
 
+	if (ops->is_port_rgmii(spx5_port->portno))
+		phy_interface_set_rgmii(spx5_port->phylink_config.supported_interfaces);
+
 	__set_bit(PHY_INTERFACE_MODE_SGMII,
 		  spx5_port->phylink_config.supported_interfaces);
 	__set_bit(PHY_INTERFACE_MODE_QSGMII,
@@ -830,6 +836,7 @@ static int mchp_sparx5_probe(struct platform_device *pdev)
 	struct initial_port_config *configs, *config;
 	struct device_node *np = pdev->dev.of_node;
 	struct device_node *ports, *portnp;
+	const struct sparx5_ops *ops;
 	struct reset_control *reset;
 	struct sparx5 *sparx5;
 	int idx = 0, err = 0;
@@ -851,6 +858,7 @@ static int mchp_sparx5_probe(struct platform_device *pdev)
 		return -EINVAL;
 
 	regs = sparx5->data->regs;
+	ops = sparx5->data->ops;
 
 	/* Do switch core reset if available */
 	reset = devm_reset_control_get_optional_shared(&pdev->dev, "switch");
@@ -880,7 +888,7 @@ static int mchp_sparx5_probe(struct platform_device *pdev)
 
 	for_each_available_child_of_node(ports, portnp) {
 		struct sparx5_port_config *conf;
-		struct phy *serdes;
+		struct phy *serdes = NULL;
 		u32 portno;
 
 		err = of_property_read_u32(portnp, "reg", &portno);
@@ -910,13 +918,17 @@ static int mchp_sparx5_probe(struct platform_device *pdev)
 			conf->sd_sgpio = ~0;
 		else
 			sparx5->sd_sgpio_remapping = true;
-		serdes = devm_of_phy_get(sparx5->dev, portnp, NULL);
-		if (IS_ERR(serdes)) {
-			err = dev_err_probe(sparx5->dev, PTR_ERR(serdes),
-					    "port %u: missing serdes\n",
-					    portno);
-			of_node_put(portnp);
-			goto cleanup_config;
+		/* There is no SerDes node for RGMII ports. */
+		if (!ops->is_port_rgmii(portno)) {
+			serdes = devm_of_phy_get(sparx5->dev, portnp, NULL);
+			if (IS_ERR(serdes)) {
+				err = dev_err_probe(sparx5->dev,
+						    PTR_ERR(serdes),
+						    "port %u: missing serdes\n",
+						    portno);
+				of_node_put(portnp);
+				goto cleanup_config;
+			}
 		}
 		config->portno = portno;
 		config->node = portnp;

drivers/net/ethernet/microchip/sparx5/sparx5_port.c

@@ -1090,6 +1090,9 @@ int sparx5_port_init(struct sparx5 *sparx5,
 		 ANA_CL_FILTER_CTRL_FILTER_SMAC_MC_DIS,
 		 sparx5, ANA_CL_FILTER_CTRL(port->portno));
 
+	if (ops->is_port_rgmii(port->portno))
+		return 0; /* RGMII device - nothing more to configure */
+
 	/* Configure MAC vlan awareness */
 	err = sparx5_port_max_tags_set(sparx5, port);
 	if (err)