[RFC 1/2] dt-bindings: topology: Add RISC-V cpu topology.

[robh+dt@kernel.org (Rob Herring)]

On Fri, Nov 2, 2018 at 8:31 AM Sudeep Holla <sudeep.holla@arm.com> wrote:
>
> On Fri, Nov 02, 2018 at 08:09:39AM -0500, Rob Herring wrote:
> > On Thu, Nov 1, 2018 at 6:04 PM Atish Patra <atish.patra@wdc.com> wrote:
> > >
> > > Define a RISC-V cpu topology. This is based on cpu-map in ARM world.
> > > But it doesn't need a separate thread node for defining SMT systems.
> > > Multiple cpu phandle properties can be parsed to identify the sibling
> > > hardware threads. Moreover, we do not have cluster concept in RISC-V.
> > > So package is a better word choice than cluster for RISC-V.
> >
> > There was a proposal to add package info for ARM recently. Not sure
> > what happened to that, but we don't need 2 different ways.
> >
>
> We still need that, I can brush it up and post what Lorenzo had previously
> proposed[1]. We want to keep both DT and ACPI CPU topology story aligned.

Frankly, I don't care what the ACPI story is. I care whether each cpu
arch does its own thing in DT or not. If a package prop works for
RISC-V folks and that happens to align with ACPI, then okay. Though I
tend to prefer a package represented as a node rather than a property
as I think that's more consistent.

Any comments on the thread aspect (whether it has ever been used)?
Though I think thread as a node level is more consistent with each
topology level being a node (same with package).

Rob