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Re: iMX6 EOMA-68 CPU Card

On Thu, Feb 28, 2013 at 01:33:14PM -0600, Bill Gatliff wrote:
> Part of me regrets being as positive about DT as I was on LAK back
> when the decision was made.  But I had just come off of a PowerPC
> project, and it worked pretty well there and so I figured, "why not?".

Yes on powerpc devicetree really does work very well.  I really don't
see why it couldn't work that well on ARM.

> I do think that DT is a good idea, and the runtime overhead is a
> manageable problem.  But it's a good idea because it creates the
> opportunity for post-compile-time flexibility, which CAN make some
> board files go away.  Not nearly as many as some of us thought they
> would however, and not without effort.

I don't see any overhead other than maybe a tiny bit when the driver
starts to determine what IRQ or GPIO line to use for a given device.

> A related problem is that about 80% of what goes on in most ARM board
> files should be done as module_init(), not board_init().  If we were
> to be more vigilant about that, then DT would have more chances to
> improve things.
> What were we talking about, again?  :-)

Maybe it is an issue of the drivers not being ready to get everything
they need to know about a given system from devicetree.  That is a lot
of work to do.

Len Sorensen

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