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>> >> + /* >> + * Do not continue on the following checks and emit bogus warning >> + * messages if the platform doesn't support frequency scaling at all. >> + */ >> + if (!cpu_feature_enabled(X86_FEATURE_HW_PSTATE)) >> + return -ENODEV; > > ... so why add this check in amd_pstate_init()? > > I personally prefer having the check in amd_cppc_supported() and > returning false from there with a pr_debug_once() saying processor does > not support frequency scaling. > FWIW I agree with Prateek here. >> + >> /* show debug message only if CPPC is not supported */ >> if (!amd_cppc_supported()) >> return -EOPNOTSUPP; >> >> --- >> base-commit: 94515f3a7d4256a5062176b7d6ed0471938cd51a >> change-id: 1cc24037-amd-pstate-vm-d6ab4c959bd3 >> >> Thanks, >> Rong >> >