Handling of modular boards

[Wolfgang Denk]

Dear Arnd,

In message <201205042039.25794.arnd at arndb.de> you wrote:
>
> > On the other hand, some of the issues we're trying to solve here
> > for the kernel are also present in the boot loader, so this needs to
> > do this anyway - whether by inserting new or modifying (enabling or
> > disabling) existing properties in the DT is not really relevant here.
> 
> I haven't seen a case where the add-on board is actually required
> for booting. What examples are you thinking of?

There are systems (and I bet it will be a growing number) where U-Boot
itself uses the DT for configuration.  Also, there are functions that
are needed both by the boot loader and the kernel - for example to
dislay a splash screen the boot loader needs to initialize the
display, so it must be able to detect which type of LCD is attached
(resolution, color-depth, orientation) - the device tree comes in very
handy here.  Why should Linux re-do all such things?

Best regards,

Wolfgang Denk

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