diff --git a/Documentation/admin-guide/pm/intel_pstate.rst b/Documentation/admin-guide/pm/intel_pstate.rst index 39d80bc29ccd..25e1097fc332 100644 --- a/Documentation/admin-guide/pm/intel_pstate.rst +++ b/Documentation/admin-guide/pm/intel_pstate.rst @@ -431,6 +431,17 @@ argument is passed to the kernel in the command line. supported in the current configuration, writes to this attribute will fail with an appropriate error. +``energy_efficiency`` + This attribute is only present on platforms, which have CPUs matching + Kaby Lake or Coffee Lake desktop CPU model. By default + energy efficiency optimizations are disabled on these CPU models in HWP + mode by this driver. Enabling energy efficiency may limit maximum + operating frequency in both HWP and non HWP mode. In non HWP mode, + optimizations are done only in the turbo frequency range. In HWP mode, + optimizations are done in the entire frequency range. Setting this + attribute to "1" enables energy efficiency optimizations and setting + to "0" disables energy efficiency optimizations. + Interpretation of Policy Attributes ----------------------------------- diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h index e8370e64a155..21b409195b46 100644 --- a/arch/x86/include/asm/msr-index.h +++ b/arch/x86/include/asm/msr-index.h @@ -149,6 +149,10 @@ #define MSR_LBR_SELECT 0x000001c8 #define MSR_LBR_TOS 0x000001c9 + +#define MSR_IA32_POWER_CTL 0x000001fc +#define MSR_IA32_POWER_CTL_BIT_EE 19 + #define MSR_LBR_NHM_FROM 0x00000680 #define MSR_LBR_NHM_TO 0x000006c0 #define MSR_LBR_CORE_FROM 0x00000040 @@ -253,8 +257,6 @@ #define MSR_PEBS_FRONTEND 0x000003f7 -#define MSR_IA32_POWER_CTL 0x000001fc - #define MSR_IA32_MC0_CTL 0x00000400 #define MSR_IA32_MC0_STATUS 0x00000401 #define MSR_IA32_MC0_ADDR 0x00000402 diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index e771e8b4f99f..fd1bef0b9bb4 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -866,10 +866,39 @@ static int intel_pstate_hwp_save_state(struct cpufreq_policy *policy) return 0; } +#define POWER_CTL_EE_ENABLE 1 +#define POWER_CTL_EE_DISABLE 2 + +static int power_ctl_ee_state; + +static void set_power_ctl_ee_state(bool input) +{ + u64 power_ctl; + + mutex_lock(&intel_pstate_driver_lock); + rdmsrl(MSR_IA32_POWER_CTL, power_ctl); + if (input) { + power_ctl &= ~BIT(MSR_IA32_POWER_CTL_BIT_EE); + power_ctl_ee_state = POWER_CTL_EE_ENABLE; + } else { + power_ctl |= BIT(MSR_IA32_POWER_CTL_BIT_EE); + power_ctl_ee_state = POWER_CTL_EE_DISABLE; + } + wrmsrl(MSR_IA32_POWER_CTL, power_ctl); + mutex_unlock(&intel_pstate_driver_lock); +} + static void intel_pstate_hwp_enable(struct cpudata *cpudata); static int intel_pstate_resume(struct cpufreq_policy *policy) { + + /* Only restore if the system default is changed */ + if (power_ctl_ee_state == POWER_CTL_EE_ENABLE) + set_power_ctl_ee_state(true); + else if (power_ctl_ee_state == POWER_CTL_EE_DISABLE) + set_power_ctl_ee_state(false); + if (!hwp_active) return 0; @@ -1218,6 +1247,32 @@ static ssize_t store_hwp_dynamic_boost(struct kobject *a, return count; } +static ssize_t show_energy_efficiency(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + u64 power_ctl; + int enable; + + rdmsrl(MSR_IA32_POWER_CTL, power_ctl); + enable = !!(power_ctl & BIT(MSR_IA32_POWER_CTL_BIT_EE)); + return sprintf(buf, "%d\n", !enable); +} + +static ssize_t store_energy_efficiency(struct kobject *a, struct kobj_attribute *b, + const char *buf, size_t count) +{ + bool input; + int ret; + + ret = kstrtobool(buf, &input); + if (ret) + return ret; + + set_power_ctl_ee_state(input); + + return count; +} + show_one(max_perf_pct, max_perf_pct); show_one(min_perf_pct, min_perf_pct); @@ -1228,6 +1283,7 @@ define_one_global_rw(min_perf_pct); define_one_global_ro(turbo_pct); define_one_global_ro(num_pstates); define_one_global_rw(hwp_dynamic_boost); +define_one_global_rw(energy_efficiency); static struct attribute *intel_pstate_attributes[] = { &status.attr, @@ -1241,6 +1297,8 @@ static const struct attribute_group intel_pstate_attr_group = { .attrs = intel_pstate_attributes, }; +static const struct x86_cpu_id intel_pstate_cpu_ee_disable_ids[]; + static void __init intel_pstate_sysfs_expose_params(void) { struct kobject *intel_pstate_kobject; @@ -1273,6 +1331,11 @@ static void __init intel_pstate_sysfs_expose_params(void) &hwp_dynamic_boost.attr); WARN_ON(rc); } + + if (x86_match_cpu(intel_pstate_cpu_ee_disable_ids)) { + rc = sysfs_create_file(intel_pstate_kobject, &energy_efficiency.attr); + WARN_ON(rc); + } } /************************** sysfs end ************************/ @@ -1288,25 +1351,6 @@ static void intel_pstate_hwp_enable(struct cpudata *cpudata) cpudata->epp_default = intel_pstate_get_epp(cpudata, 0); } -#define MSR_IA32_POWER_CTL_BIT_EE 19 - -/* Disable energy efficiency optimization */ -static void intel_pstate_disable_ee(int cpu) -{ - u64 power_ctl; - int ret; - - ret = rdmsrl_on_cpu(cpu, MSR_IA32_POWER_CTL, &power_ctl); - if (ret) - return; - - if (!(power_ctl & BIT(MSR_IA32_POWER_CTL_BIT_EE))) { - pr_info("Disabling energy efficiency optimization\n"); - power_ctl |= BIT(MSR_IA32_POWER_CTL_BIT_EE); - wrmsrl_on_cpu(cpu, MSR_IA32_POWER_CTL, power_ctl); - } -} - static int atom_get_min_pstate(void) { u64 value; @@ -1982,10 +2026,6 @@ static int intel_pstate_init_cpu(unsigned int cpunum) if (hwp_active) { const struct x86_cpu_id *id; - id = x86_match_cpu(intel_pstate_cpu_ee_disable_ids); - if (id) - intel_pstate_disable_ee(cpunum); - intel_pstate_hwp_enable(cpu); id = x86_match_cpu(intel_pstate_hwp_boost_ids); @@ -2806,8 +2846,17 @@ static int __init intel_pstate_init(void) if (rc) return rc; - if (hwp_active) + if (hwp_active) { + const struct x86_cpu_id *id; + + id = x86_match_cpu(intel_pstate_cpu_ee_disable_ids); + if (id) { + set_power_ctl_ee_state(false); + pr_info("Disabling energy efficiency optimization\n"); + } + pr_info("HWP enabled\n"); + } return 0; }