cpufreq: intel_pstate: hybrid: Use known scaling factor for P-cores
Commit 46573fd6 ("cpufreq: intel_pstate: hybrid: Rework HWP calibration") attempted to use the information from CPPC (the nominal performance in particular) to obtain the scaling factor allowing the frequency to be computed if the HWP performance level of the given CPU is known or vice versa. However, it turns out that on some platforms this doesn't work, because the CPPC information on them does not align with the contents of the MSR_HWP_CAPABILITIES registers. This basically means that the only way to make intel_pstate work on all of the hybrid platforms to date is to use the observation that on all of them the scaling factor between the HWP performance levels and frequency for P-cores is 78741 (approximately 100000/1.27). For E-cores it is 100000, which is the same as for all of the non-hybrid "core" platforms and does not require any changes. Accordingly, make intel_pstate use 78741 as the scaling factor between HWP performance levels and frequency for P-cores on all hybrid platforms and drop the dependency of the HWP calibration code on CPPC. Fixes: 46573fd6 ("cpufreq: intel_pstate: hybrid: Rework HWP calibration") Reported-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Cc: 5.15+ <stable@vger.kernel.org> # 5.15+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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