On 14/11/2022 15.51, Viresh Kumar wrote: > On 09-11-22, 21:36, Hector Martin wrote: >> On 02/11/2022 15.18, Viresh Kumar wrote: >>>> + ret = dev_pm_opp_set_sharing_cpus(cpu_dev, policy->cpus); >>> >>> Why do you need this ? The OPP core should be able to find this >>> information by itself in your case AFAIU. The OPP core will refer >>> "operating-points-v2 = <&pcluster_opp>" and find that the cores are >>> related. >> >> We have multiple clusters sharing an OPP table (e.g. the M1 Ultra has 2 >> e-cluster and 4 p-clusters, and duplicating OPP tables seems very >> silly), so this is necessary to tell it about the subset of cores >> sharing a table that are actually one domain. > > The cluster sharing information is already part of the OPP tables, "opp-shared" > property. Platforms like scpi needed this because they didn't have the OPP table > in DT and so no way to find out the relation of the CPUs. > > See how drivers/cpufreq/mediatek-cpufreq.c has done this. > dev_pm_opp_of_get_sharing_cpus() followed by dev_pm_opp_of_cpumask_add_table(). I don't think you understood me. We have multiple identical clusters. All those clusters share an OPP table but are *not* the same cpufreq domain. So we can have 8 CPUs which are two 4-CPU cluster using one OPP table. There is no way to express this relationship with OPP tables without duplicating the tables themselves. - Hector
