[PATCHv4 3/6] ARM: dts: Add initial LS1021A TWR board dts support

[arnd@arndb.de (Arnd Bergmann)]

On Wednesday 24 September 2014 05:47:53 Jingchang Lu wrote:
> 
> The ethernet device nodes already have the phy-handle properties to their mdio nodes.
> 
> The alias for PHY nodes here is:
>   The ethernet has two kind of PHY interface, one is SGMII, and the other is RGMII,
> The selection is done by the reset configuration word(RCW), so Phy-handle properties
> should be change properly to reflecting the PHY interface selection. This is done
> by fixing up dtb in u-boot before booting the kernel. Thus the alias for PHY nodes
> is added here for fdt finding the PHY nodes easily.

Ok, I see. I thought that this was what the labels in the dtb were supposed
to be used for. Can't you do the same thing in u-boot by using a label
as opposed to the alias?

IIRC you should be able to add an additional label like

+&mdio0 {
+       enet1_sgmii_phy: sgmii_phy0: ethernet-phy at 0 {
+               reg = <0x0>;
+       };

and then use libfdt to find the node through that, rather than through
the alias. I don't know how things are handled on other platforms, but
I think that was how it was initially thought up when we introduced
the fdt format on PowerPC.

	Arnd