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

[Pali Rohár]

On Tuesday 09 August 2022 14:39:05 Tim Harvey wrote:
> I've been wondering the same as well which made me wonder what the
> history of the 'aliases' node is and why its not used in most cases in
> Linux. I know for the SOC's I work with we've always defined aliases
> for ethernet<n>, gpio<n>, serial<n>, spi<n>, i2c<n>, mmc<n> etc. Where
> did this practice come from and why are we putting that in Linux dts
> files it if it's not used by Linux?

U-Boot can modify on-the-fly Linux's DTB file when booting Linux kernel.
For example it can put permanent MAC address into ethernet nodes from
U-Boot env. Similarly it can modify other DT nodes.

So even when Linux itself does not use particular alias, it is used by
the bootloader.