diff options
| -rw-r--r-- | Documentation/admin-guide/pm/intel_pstate.rst | 6 | ||||
| -rw-r--r-- | drivers/cpufreq/intel_pstate.c | 50 |
2 files changed, 45 insertions, 11 deletions
diff --git a/Documentation/admin-guide/pm/intel_pstate.rst b/Documentation/admin-guide/pm/intel_pstate.rst index 25e1097fc332..40d481cca368 100644 --- a/Documentation/admin-guide/pm/intel_pstate.rst +++ b/Documentation/admin-guide/pm/intel_pstate.rst @@ -565,7 +565,11 @@ somewhere between the two extremes: Strings written to the ``energy_performance_preference`` attribute are internally translated to integer values written to the processor's Energy-Performance Preference (EPP) knob (if supported) or its -Energy-Performance Bias (EPB) knob. +Energy-Performance Bias (EPB) knob. It is also possible to write a positive +integer value between 0 to 255, if the EPP feature is present. If the EPP +feature is not present, writing integer value to this attribute is not +supported. In this case, user can use + "/sys/devices/system/cpu/cpu*/power/energy_perf_bias" interface. [Note that tasks may by migrated from one CPU to another by the scheduler's load-balancing algorithm and if different energy vs performance hints are diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index fd1bef0b9bb4..44c7b4677675 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -602,11 +602,12 @@ static const unsigned int epp_values[] = { HWP_EPP_POWERSAVE }; -static int intel_pstate_get_energy_pref_index(struct cpudata *cpu_data) +static int intel_pstate_get_energy_pref_index(struct cpudata *cpu_data, int *raw_epp) { s16 epp; int index = -EINVAL; + *raw_epp = 0; epp = intel_pstate_get_epp(cpu_data, 0); if (epp < 0) return epp; @@ -614,12 +615,14 @@ static int intel_pstate_get_energy_pref_index(struct cpudata *cpu_data) if (boot_cpu_has(X86_FEATURE_HWP_EPP)) { if (epp == HWP_EPP_PERFORMANCE) return 1; - if (epp <= HWP_EPP_BALANCE_PERFORMANCE) + if (epp == HWP_EPP_BALANCE_PERFORMANCE) return 2; - if (epp <= HWP_EPP_BALANCE_POWERSAVE) + if (epp == HWP_EPP_BALANCE_POWERSAVE) return 3; - else + if (epp == HWP_EPP_POWERSAVE) return 4; + *raw_epp = epp; + return 0; } else if (boot_cpu_has(X86_FEATURE_EPB)) { /* * Range: @@ -638,7 +641,8 @@ static int intel_pstate_get_energy_pref_index(struct cpudata *cpu_data) } static int intel_pstate_set_energy_pref_index(struct cpudata *cpu_data, - int pref_index) + int pref_index, bool use_raw, + u32 raw_epp) { int epp = -EINVAL; int ret; @@ -657,6 +661,16 @@ static int intel_pstate_set_energy_pref_index(struct cpudata *cpu_data, value &= ~GENMASK_ULL(31, 24); + if (use_raw) { + if (raw_epp > 255) { + ret = -EINVAL; + goto return_pref; + } + value |= (u64)raw_epp << 24; + ret = wrmsrl_on_cpu(cpu_data->cpu, MSR_HWP_REQUEST, value); + goto return_pref; + } + if (epp == -EINVAL) epp = epp_values[pref_index - 1]; @@ -694,6 +708,8 @@ static ssize_t store_energy_performance_preference( { struct cpudata *cpu_data = all_cpu_data[policy->cpu]; char str_preference[21]; + bool raw = false; + u32 epp; int ret; ret = sscanf(buf, "%20s", str_preference); @@ -701,10 +717,21 @@ static ssize_t store_energy_performance_preference( return -EINVAL; ret = match_string(energy_perf_strings, -1, str_preference); - if (ret < 0) + if (ret < 0) { + if (!boot_cpu_has(X86_FEATURE_HWP_EPP)) + return ret; + + ret = kstrtouint(buf, 10, &epp); + if (ret) + return ret; + + raw = true; + } + + ret = intel_pstate_set_energy_pref_index(cpu_data, ret, raw, epp); + if (ret) return ret; - intel_pstate_set_energy_pref_index(cpu_data, ret); return count; } @@ -712,13 +739,16 @@ static ssize_t show_energy_performance_preference( struct cpufreq_policy *policy, char *buf) { struct cpudata *cpu_data = all_cpu_data[policy->cpu]; - int preference; + int preference, raw_epp; - preference = intel_pstate_get_energy_pref_index(cpu_data); + preference = intel_pstate_get_energy_pref_index(cpu_data, &raw_epp); if (preference < 0) return preference; - return sprintf(buf, "%s\n", energy_perf_strings[preference]); + if (raw_epp) + return sprintf(buf, "%d\n", raw_epp); + else + return sprintf(buf, "%s\n", energy_perf_strings[preference]); } cpufreq_freq_attr_rw(energy_performance_preference); |