Messages in this thread | | | From | Rob Herring <> | Date | Fri, 23 Oct 2020 08:34:05 -0500 | Subject | Re: [PATCH 1/2] dt-bindings: arm,scmi: Do not use clocks for SCMI performance domains |
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On Wed, Oct 21, 2020 at 1:19 PM Sudeep Holla <sudeep.holla@arm.com> wrote: > > On Wed, Oct 21, 2020 at 11:20:27AM -0500, Rob Herring wrote: > > On Tue, Oct 20, 2020 at 3:37 PM Sudeep Holla <sudeep.holla@arm.com> wrote: > > > > > [...] > > > > > When is this not 1 (IOW, you only need this if variable)? How would it > > be used outside SCMI (given it has a generic name)? > > > > > + > > > +* Property arm,scmi-perf-domain > > > [...] > > > Really though, why can't you give SCMI a CPUs MPIDR and get its domain? > > > > Now I remembered why we can't use MPIDR. The spec talks about perf domains > for devices in generic. CPU is just a special device. We will still need > a mechanism to get device performance domain. So MPIDR idea was dropped to > keep it uniform across all the devices.
What implications to the binding are there for non-CPU devices? Do they need more cells? How does this integrate our plethora of other PM related bindings?
So somewhere in the firmware we're defining device X is domain 0, device Y is domain 1, etc. Then we do this again in DT. Seems fragile to define this information twice. I guess that's true for any number space SCMI defines.
Rob
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