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> > + > > + if ((read_cpuid_id() & MIDR_CPU_MODEL_MASK) != MIDR_NVIDIA_OLYMPUS) > > + return; > > + > > + if (!topology_core_has_smt(smp_processor_id())) > > + return; > > + > > + set_sched_topology(arm64_asym_smt_topology); > > + pr_info("Enabling PE0 SMT preference for NVIDIA Olympus\n"); > > I'm not really a big fan of using this arm64 setup for NVIDIA Olympus > alone here. > > > +} > > + > > +int arch_asym_cpu_priority(int cpu) > > +{ > > + return MPIDR_AFFINITY_LEVEL(cpu_logical_map(cpu), 0) == 0; > > +} > > + > > This is done since it will only be called for NVIDIA Olympus since it's > the only CPU model enabling this. I think it will work but it's still > ugly :-) > > [...] > Agreed on both points. As mentioned in the other email, I'll coordinate with the firmware team on a proper ABI for describing the PE0 preference. For the systems with the current firmware, I don't have many ideas on how to enable this... a special scheduler facility enabled via kernel boot option? Other ideas? Thanks, -Andrea