Re: [PATCH 11/13] dt-bindings: mips: Add loongson cpus & boards

From: Paul Burton
Date: Tue Sep 03 2019 - 05:07:57 EST

Hi Rob,

On Mon, Sep 02, 2019 at 03:50:47PM +0100, Rob Herring wrote:
> > In general on MIPS we detect CPU properties at runtime from coprocessor
> > 0 registers & similar sources of information, so there's not really a
> > need to specify anything about the CPU in devicetree.
> We thought the same thing initially for Arm... Mostly what is in DT is
> not what is discoverable. Are clock speeds, power domains, low power
> states, etc. all discoverable?

No, that's a good point - clocks etc may need to be specified in DT. I
just don't see any of that in this patchset - it appears all that is
specified is cache sizes which we already detect. So in this case I
don't see a need for including CPUs in DT at all.

Jiaxun - did you add all this information to DT to avoid the "cacheinfo:
Unable to detect cache hierarchy for CPU" messages during boot? If so
that should be fixed by commit b8bea8a5e5d9 ("mips: fix cacheinfo"). If
not, could you describe why the CPU nodes are needed here?