[PATCH 4/6] arm64: topology: Implement basic CPU topology support

[Catalin Marinas]

On Mon, Dec 16, 2013 at 03:12:32PM +0000, Mark Brown wrote:
> On Mon, Dec 16, 2013 at 02:46:38PM +0000, Lorenzo Pieralisi wrote:
> > On Mon, Dec 16, 2013 at 12:29:48PM +0000, Mark Brown wrote:
> [MPIDR parsing]
> > > Again, this is gone from the current version.  Like I said to Catalin it
> > > does feel like this is making more work for systems that have done the
> > > right thing with their MPIDRs which doesn't seem ideal (and note that
> > > all the DTs that you guys are publishing for your models lack any
> > > topology information at present).
> 
> > This is an age-old question and the problem has always been that the
> > "right thing" is recommended, not enforced. I do not want to turn this into
> > bikeshedding, as long as cpu-map node takes priority if present, fine by me.
> 
> I already dropped that code, though I could resurrect it (perhaps as a
> separate patch).  The way the code was written was as you describe as a
> last resort - MPIDR would only be considered if the explict topology
> binding was not present, it was done as a last step before reporting if
> no other topology information was discovered.
> 
> Actually now I think about it if we're not going to parse the MPIDR we
> should probably update the bindings to say that the topology binding is
> mandatory for any v8 system with more than one core.

Do we need such information if only a flat topology is needed?

-- 
Catalin