Re: [PATCH 2/3] Derive ebc ranges property from EBC registers

[Segher Boessenkool <segher@kernel.crashing.org>]

>> Do we want a "ranges;" here as a placeholder?  I don't see where it's
>> absolutely required, but it makes me feel better for some reason...
>
> Absolutely not.  An empty ranges property indicates that the child bus
> address space is the same as the parent bus address space.

Or a subset of it, anyway; both address domains have to
use the same representation in "reg" properties, and the
mapping has to be 1-1.

A missing "ranges" property means there is no direct
mapping, which is more correct in this case, and perfectly
valid.

> If we're
> using the chip-select/offset addressing form for the EBC peripherals,
> that's manifestly not the case.

This would be a nice use case for the

	ranges = ??;

syntax when/if that gets added to DTC and the kernel
and bootwrapper parsers for DTBs.


Segher