Re: RFC: Location for Device Tree Sources?

On 8/3/06, Kumar Gala [off-list ref] wrote:

On Aug 2, 2006, at 1:57 PM, Tom Rini wrote:

quoted

On Wed, Aug 02, 2006 at 01:23:08PM -0500, Jon Loeliger wrote:

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On Wed, 2006-08-02 at 13:21, Tom Rini wrote:

quoted

Yes, as I said, I'm not totally sure we're at the stable point right
now, but I think that we are.  I'll add that maybe we need to think
about API changes and DTS format versions.  To quote from my post..

quoted

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X bugs) or a change that requires a dts version bump.

Now it sounds like the IRQ thing was an "Oops, we should have
changed
the dts version" and bailed, noting what is wrong with the dts.

This confuses me.  There hasn't been a change in the DTS
format at all.  I've even updated the 8641HPCN DTS file
across the IRQ updates and all is fine.  Same (DTS) format
both before and after the IRQ changes.

What have I missed here?

Matthew said:

quoted

The sandpoint (as far as I know) does not have a stable DTS. So in
this
case including the DTS in the kernel would reduce confusion. The same
could be said for other boards where the DTS needed to be changed for
the IRQ rework. The old DTS will no longer boot the new kernels.
I'm not
sure how much longer we will run into this problem though.

Now, if we've had to change the contents of the DTS because of a
kernel
change, I'd say the DTS format changed as when I say format I mean not
only layout and naming, but what the contents are supposed to contain.

And, so it's clear, I don't know if we're at the very stable format
(names/layout/content means...), but when we are at that point, what
Matthew noted should, IMHO, be a graceful (ie explained in the panic()
or something) death.

And, so it's clear, I think (and hope!) we all agree on that last
part,
once we hit stability.

Agree about the comments related to the stability of the API, I just
dont think we are there yet.  We should revisit the issue when we
removed arch/ppc, until that point I would say things are up in the air.

For example, we still haven't closed on CPM descriptions and I'm sure
we will go through several iterations before we get it right.  For
more standard things like uart's, ethernet, pci we have the OF specs
to model off of and are probably pretty stable.

I agree.  We are adding more and more device types under device tree
management.  There will be a process of evolution.

Additionally, Ben and I have talked about making macro's in the dts's
so we can build up a board or SOC description from standard building
blocks so people dont get the simple things wrong.

What are the macros about? Like constant we used in source code?

- kumar

- Leo