On Thu, 24 Oct 2019 at 17:26, Sudeep Holla <sudeep.holla@xxxxxxx> wrote: > > On Thu, Oct 10, 2019 at 01:39:26PM +0200, Ulf Hansson wrote: > > Update PSCI DT bindings to allow to represent idle states for CPUs and the > > CPU topology, by using a hierarchical layout. Primarily this is done by > > re-using the existing power domain description [1] and the domain idle > > state description [2]. > > > > Let's also take the opportunity to update the examples to clarify the > > difference between the currently supported flattened layout vs the new > > hierarchical layout. > > > > This looks fine to me. FWIW: > > Reviewed-by: Sudeep Holla <sudeep.holla@xxxxxxx> > > But before this gets merged, I would like to add another but "the golden" > example Qcom *always* referred during ACPI LPI discussions. Ofcourse, it > can be addition patch and if I get time, I can write this but no promise > ATM. I like the description below, thanks for clarifying that. Although, as you say, we can for sure add it on top. As a matter of fact, I think that is even the best way forward, as currently we can't support it (because of limitations in genpd, that I have started working on a bit). > > Hierarchical Representation: > System > 1. SYSTEM_RET > 2. SYSTEM_PG > > Cluster#0 > 1. CLUSTER_RET > 2. CLUSTER_PG > > Core#0 > 1. CORE_CG > 2. CORE_RET > 3. CORE_PG > > Core#1 > 1. CORE_CG > 2. CORE_RET > 3. CORE_PG > Cluster#1 (ditto) > > Flattened Representation: > > Core#0 > 1 CORE_CG > 2 CORE_RET > 3 CORE_RET + CLUSTER_RET > 4 CORE_RET + CLUSTER_RET + SYSTEM_RET > 5 CORE_PG > 6 CORE_PG + CLUSTER_RET > 7 CORE_PG + CLUSTER_RET + SYSTEM_RET > 8 CORE_PG + CLUSTER_PG > 9 CORE_PG + CLUSTER_PG + SYSTEM_RET > 10 CORE_PG + CLUSTER_PG + SYSTEM_PG > > Though we may not implement everything needed to support this, but > we must ensure we don't have to end up in a situation breaking backward > compatibility trying to support the same. Yep, right. I don't see any issue in regards to backward compatibility to support this above. Thanks for reviewing! Kind regards Uffe
