Re: [PATCH net-next v2 4/6] net: mdio: scan bus based on bus capabilities for C22 and C45

[Andrew Lunn <andrew@lunn.ch>]

> Here's the definition of the switch in the Turris Omnia device tree.
> 
> 	/* Switch MV88E6176 at address 0x10 */
> 	switch@10 {
> 		pinctrl-names = "default";
> 		pinctrl-0 = <&swint_pins>;
> 		compatible = "marvell,mv88e6085";
> 		#address-cells = <1>;
> 		#size-cells = <0>;
> 
> 		dsa,member = <0 0>;
> 		reg = <0x10>;
> 
> 		interrupt-parent = <&gpio1>;
> 		interrupts = <13 IRQ_TYPE_LEVEL_LOW>;
> 
> 		ports {
> 			#address-cells = <1>;
> 			#size-cells = <0>;
> 
> 			ports@0 {
> 				reg = <0>;
> 				label = "lan0";
> 			};
> 
> 			ports@1 {
> 				reg = <1>;
> 				label = "lan1";
> 			};
> 
> 			ports@2 {
> 				reg = <2>;
> 				label = "lan2";
> 			};
> 
> 			ports@3 {
> 				reg = <3>;
> 				label = "lan3";
> 			};
> 
> 			ports@4 {
> 				reg = <4>;
> 				label = "lan4";
> 			};
> 
> 			ports@5 {
> 				reg = <5>;
> 				label = "cpu";
> 				ethernet = <&eth1>;
> 				phy-mode = "rgmii-id";
> 
> 				fixed-link {
> 					speed = <1000>;
> 					full-duplex;
> 				};
> 			};
> 
> 			ports@6 {
> 				reg = <6>;
> 				label = "cpu";
> 				ethernet = <&eth0>;
> 				phy-mode = "rgmii-id";
> 
> 				fixed-link {
> 					speed = <1000>;
> 					full-duplex;
> 				};
> 			};
> 		};
> 
> What you are proposing here would not show any improvement on the
> Omnia, as only the 6 ports would be scanned - right? 

Correct. But their also should not of been any noticeable slow down,
because there should not be any additional scanning when everything is
described in DT. And the move of the MDIO bus registration from probe
to setup should actually make it faster than before.

	  Andrew