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

[Michal Suchánek]

On Mon, Aug 08, 2022 at 03:57:55PM -0400, Sean Anderson wrote:
> 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

Maybe it's a great opportunity for porting biosdevname to DT based
platforms ;-)

Thanks

Michal