diff options
| author | Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> | 2016-04-27 15:48:08 -0700 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2016-04-28 01:01:39 +0200 |
| commit | 2b3ec765058449caa27e2806a939a4bffcbeba64 (patch) | |
| tree | 4c5170e80c1b4f0c8eb4e323bfb821ae7d42b4ba | |
| parent | 3be9200d512bfa8d6292f5dce6c02aa151821e09 (diff) | |
cpufreq: intel_pstate: Enable PPC enforcement for servers
For platforms which are controlled via remove node manager, enable _PPC by
default. These platforms are mostly categorized as enterprise server or
performance servers. These platforms needs to go through some
certifications tests, which tests control via _PPC.
The relative risk of enabling by default is low as this is is less likely
that these systems have broken _PSS table.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
| -rw-r--r-- | Documentation/kernel-parameters.txt | 5 | ||||
| -rw-r--r-- | drivers/cpufreq/intel_pstate.c | 12 |
2 files changed, 15 insertions, 2 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 31c094fb1141..1cffa3f24732 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1662,7 +1662,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted. Only load intel_pstate on systems which support hardware P state control (HWP) if available. support_acpi_ppc - Enforce ACPI _PPC performance limits. + Enforce ACPI _PPC performance limits. If the Fixed ACPI + Description Table, specifies preferred power management + profile as "Enterprise Server" or "Performance Server", + then this feature is turned on by default. intremap= [X86-64, Intel-IOMMU] on enable Interrupt Remapping (default) diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index 31f6ffe0cf10..a0823e84ceca 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -347,6 +347,16 @@ static struct perf_limits *limits = &powersave_limits; #endif #ifdef CONFIG_ACPI + +static bool intel_pstate_get_ppc_enable_status(void) +{ + if (acpi_gbl_FADT.preferred_profile == PM_ENTERPRISE_SERVER || + acpi_gbl_FADT.preferred_profile == PM_PERFORMANCE_SERVER) + return true; + + return acpi_ppc; +} + /* * The max target pstate ratio is a 8 bit value in both PLATFORM_INFO MSR and * in TURBO_RATIO_LIMIT MSR, which pstate driver stores in max_pstate and @@ -370,7 +380,7 @@ static void intel_pstate_init_acpi_perf_limits(struct cpufreq_policy *policy) int ret; int i; - if (!acpi_ppc) + if (!intel_pstate_get_ppc_enable_status()) return; cpu = all_cpu_data[policy->cpu]; |