]> git.baikalelectronics.ru Git - kernel.git/commit
cpufreq: intel_pstate: Also use CPPC nominal_perf for base_frequency
authorSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Mon, 25 Mar 2019 16:04:40 +0000 (09:04 -0700)
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>
Mon, 25 Mar 2019 22:57:21 +0000 (23:57 +0100)
commitbe933e4e30d90b594387209d8ae3b513227f989f
treef06ebdfb09105845f176608a015be1da5edea151
parent11c7eefd7cc0d3c60248609a87068dc45f24a4a1
cpufreq: intel_pstate: Also use CPPC nominal_perf for base_frequency

The ACPI specification states that if the "Guaranteed Performance
Register" is not implemented, the OSPM assumes guaranteed performance
to always be equal to nominal performance.

So for invalid or unimplemented guaranteed performance register, use
nominal performance as guaranteed performance.

This change will fall back to nominal_perf when guranteed_perf is
invalid.  If nominal_perf is also invalid or not present, fall back
to the existing implementation, which is to read from HWP Capabilities
MSR.

Fixes: d5ab2c6b2375 ("cpufreq: intel_pstate: Add base_frequency attribute")
Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: 4.20+ <stable@vger.kernel.org> # 4.20+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
drivers/cpufreq/intel_pstate.c