ethernet<n> dt aliases implications in U-Boot and Linux

[Sean Anderson]

Hi Tim,

On 8/8/22 3:18 PM, Tim Harvey wrote:
> Greetings,
> 
> I'm trying to understand if there is any implication of 'ethernet<n>'
> aliases in Linux such as:
>         aliases {
>                 ethernet0 = &eqos;
>                 ethernet1 = &fec;
>                 ethernet2 = &lan1;
>                 ethernet3 = &lan2;
>                 ethernet4 = &lan3;
>                 ethernet5 = &lan4;
>                 ethernet6 = &lan5;
>         };
> 
> I know U-Boot boards that use device-tree will use these aliases to
> name the devices in U-Boot such that the device with alias 'ethernet0'
> becomes eth0 and alias 'ethernet1' becomes eth1 but for Linux it
> appears that the naming of network devices that are embedded (ie SoC)
> vs enumerated (ie pci/usb) are always based on device registration
> order which for static drivers depends on Makefile linking order and
> has nothing to do with device-tree.
> 
> Is there currently any way to control network device naming in Linux
> other than udev?

You can also use systemd-networkd et al. (but that is the same kind of mechanism)

> Does Linux use the ethernet<n> aliases for anything at all?

No :l

--Sean