cpufreq: CPPC: Mark driver with NEED_UPDATE_LIMITS flag
AMU counters on certain CPPC-based platforms tend to yield inaccurate delivered performance measurements on systems that are idle/mostly idle. This results in an inaccurate frequency being stored by cpufreq in its policy structure when the CPU is brought online. [1] Consequently, if the userspace governor tries to set the frequency to a new value, there is a possibility that it would be the erroneous value stored earlier. In such a scenario, cpufreq would assume that the requested frequency has already been set and return early, resulting in the correct/new frequency request never making it to the hardware. Since the operating frequency is liable to this sort of inconsistency, mark the CPPC driver with CPUFREQ_NEED_UPDATE_LIMITS so that it is always invoked when a target frequency update is requested. Link: https://lore.kernel.org/linux-pm/20250619000925.415528-3-pmalani@google.com/ [1] Suggested-by:Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by:
Prashant Malani <pmalani@google.com> Acked-by:
Viresh Kumar <viresh.kumar@linaro.org> Link: https://patch.msgid.link/20250722055611.130574-2-pmalani@google.com Signed-off-by:
Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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