Re: [PATCH 14/18] ARM: mvebu: add support for the Armada 395 SoC family

On Mon, Jul 25, 2016 at 8:50 AM, Thomas Petazzoni
[off-list ref] wrote:

Hello,

On Mon, 25 Jul 2016 08:47:23 -0500, Rob Herring wrote:

quoted

quoted

I am not sure if I get your point. The Armada-398 extends the
Armada-395 about 2 additional SATA ports (as you can see in commit
"[PATCH 15/18] ARM: mvebu: a398: update the dtsi about missing
interfaces"). In this example the a398-db board contains the Armada398
SoC, so it is a better match and goes first.

But your patch title is adding 395 support, but you are adding the
string to a 398 based board. It would make sense to have 395 here if
the OS already had support for 395 and you want to support the 398
without updating the OS. That doesn't seem to apply here.

I think the argument of Grzegorz is that the 398 is functionally a
strict superset of the 395, so that anything that applies to the 395
will also apply to 398.

Yes, I get that, but that is only meaningful if you want to run an OS
that is only aware of 395 on a 398 SoC/board (though I'd guess the 390
compat is enough for that). Otherwise, that property is not really
meaningful as the additional nodes are enough to handle what is the
superset.

I would agree both are fine if both chips are in fact the same die,
just fused or packaged differently. I've seen a lot of chips that are
supposed to be sub/supersets of each other, but have different errata
lists because they are different die.

Rob