| Message ID | 20190325160440.7575-3-srinivas.pandruvada@linux.intel.com (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Delegated to: | Rafael Wysocki |
| Headers | show |
| Series | Correct the processing for base_frequency | expand |
diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index e22f0dbaebb1..b599c7318aab 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -385,7 +385,10 @@ static int intel_pstate_get_cppc_guranteed(int cpu) if (ret) return ret; - return cppc_perf.guaranteed_perf; + if (cppc_perf.guaranteed_perf) + return cppc_perf.guaranteed_perf; + + return cppc_perf.nominal_perf; } #else /* CONFIG_ACPI_CPPC_LIB */
ACPI specifications stat that if the "Guaranteed Performance Register" is not implemented, OSPM assumes guaranteed performance is always equal to nominal performance. So for invalid and unimplemented guaranteed performance register, use nominal performance as guaranteed performance. This change will fallback to nominal_perf when guranteed_perf is invalid. If nominal_perf is also invalid, then fallback to existing implementation, which is to read from HWP Capabilities MSR. Fixes: 86d333a8cc7f ("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+ --- drivers/cpufreq/intel_pstate.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)