Hi Mark,

On Jul 5, 2016, at 11:31 , Mark Brown [off-list ref] wrote:

On Mon, Jul 04, 2016 at 01:58:53PM -0700, Frank Rowand wrote:

quoted

On the other hand, I have no previous detailed knowledge of the beagle
family.

This is in no way specific to the BeagleBones, there's plenty of other
boards out there with similar setups like the Raspberry Pi and its
derivatives.  

There are a lot of custom vendor boards that use it.
We need to handle custom board too.

quoted

   - for bones with the same pinout:
     - the pins are routed to different function blocks on the
       SOC because different bones may have different SOCs?
       - the different functional blocks are compatible or not?

This is the general case, there will be a substantial level of
compatibility between different base boards by virtue of the pinouts
being the same but obviously there will be some variation in the
specifics (and even where that exists it may not be enough to be visible
at the DT level for the most part).  That said there will doubtless be
some plug in modules that want to rely on the specifics of a given base
board rather than remain compatible with general users of the interface.

Even for plug in modules that need a specific board it is typical that new
SoCs/boards appear in the future that are backwards compatible.

Regards

— Pantelis