[PATCH 2/3] Derive ebc ranges property from EBC registers
Segher Boessenkool
segher at kernel.crashing.org
Wed May 16 23:28:16 EST 2007
>> 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
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