| Message ID | 20250304152327.1561017-2-superm1@kernel.org (mailing list archive) |
|---|---|
| State | New |
| Delegated to: | Mario Limonciello |
| Headers | show |
| Series | amd-pstate Dynamic EPP and raw EPP | expand |
Hello Mario, On Tue, Mar 04, 2025 at 09:23:23AM -0600, Mario Limonciello wrote: > From: Mario Limonciello <mario.limonciello@amd.com> > > Dynamic energy performance preference will change the EPP profile > based on whether the machine is running on AC or DC power. > > A notification chain from the power supply core is used to adjust > EPP values on plug in or plug out events. > > For non-server systems: > * the default EPP for AC mode is `performance`. > * the default EPP for DC mode is `balance_performance`. > > Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> > --- > v1->v2: > * Change defaults to performance (AC) and balance_performance (DC) > * Default Kconfig to disabled for now > * Rebase on latest branch > --- > Documentation/admin-guide/pm/amd-pstate.rst | 18 ++- > drivers/cpufreq/Kconfig.x86 | 12 ++ > drivers/cpufreq/amd-pstate.c | 129 ++++++++++++++++++-- > drivers/cpufreq/amd-pstate.h | 5 +- > 4 files changed, 155 insertions(+), 9 deletions(-) > > diff --git a/Documentation/admin-guide/pm/amd-pstate.rst b/Documentation/admin-guide/pm/amd-pstate.rst > index 412423c54f258..2e076650dc77c 100644 > --- a/Documentation/admin-guide/pm/amd-pstate.rst > +++ b/Documentation/admin-guide/pm/amd-pstate.rst [...snip..] > @@ -311,6 +311,22 @@ boost or `1` to enable it, for the respective CPU using the sysfs path > Other performance and frequency values can be read back from > ``/sys/devices/system/cpu/cpuX/acpi_cppc/``, see :ref:`cppc_sysfs`. > > +Dynamic energy performance profile > +================================== > +The amd-pstate driver supports dynamically selecting the energy performance > +profile based on whether the machine is running on AC or DC power. > + > +Whether this behavior is enabled by default with the kernel config option > +`CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP`. This behavior can also be overridden > +at runtime by the sysfs file ``/sys/devices/system/cpu/cpufreq/policyX/dynamic_epp``. > + > +When set to enabled, the driver will select a different energy performance > +profile when the machine is running on battery or AC power. > +When set to disabled, the driver will not change the energy performance profile > +based on the power source and will not react to user desired power state. > + > +Attempting to manually write to the ``energy_performance_preference`` sysfs > +file will fail when ``dynamic_epp`` is enabled. > > ``amd-pstate`` vs ``acpi-cpufreq`` > ====================================== > diff --git a/drivers/cpufreq/Kconfig.x86 b/drivers/cpufreq/Kconfig.x86 > index 97c2d4f15d76e..c5ef92634ddf4 100644 > --- a/drivers/cpufreq/Kconfig.x86 > +++ b/drivers/cpufreq/Kconfig.x86 > @@ -68,6 +68,18 @@ config X86_AMD_PSTATE_DEFAULT_MODE > For details, take a look at: > <file:Documentation/admin-guide/pm/amd-pstate.rst>. > > +config X86_AMD_PSTATE_DYNAMIC_EPP > + bool "AMD Processor P-State dynamic EPP support" > + depends on X86_AMD_PSTATE > + default n > + help > + Allow the kenrel to dynamically change the energy performance ^^^^^^ kernel > + value from events like ACPI platform profile and AC adapter plug > + events. > + > + This feature can also be changed at runtime, this configuration > + option only sets the kernel default value behavior. > + > config X86_AMD_PSTATE_UT > tristate "selftest for AMD Processor P-State driver" > depends on X86 && ACPI_PROCESSOR > diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c > index e98ef41083ba1..f00fb4ba9f26e 100644 > --- a/drivers/cpufreq/amd-pstate.c > +++ b/drivers/cpufreq/amd-pstate.c > @@ -36,6 +36,7 @@ > #include <linux/io.h> > #include <linux/delay.h> > #include <linux/uaccess.h> > +#include <linux/power_supply.h> > #include <linux/static_call.h> > #include <linux/topology.h> > > @@ -86,6 +87,7 @@ static struct cpufreq_driver amd_pstate_driver; > static struct cpufreq_driver amd_pstate_epp_driver; > static int cppc_state = AMD_PSTATE_UNDEFINED; > static bool amd_pstate_prefcore = true; > +static bool dynamic_epp = CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP; > static struct quirk_entry *quirks; > > /* > @@ -1050,6 +1052,73 @@ static void amd_pstate_cpu_exit(struct cpufreq_policy *policy) > kfree(cpudata); > } > > +static int amd_pstate_get_balanced_epp(struct cpufreq_policy *policy) Can we rename this function as amd_pstate_get_dynamic_epp() ? Because the values being returned may not be balance_performance/balance_power. > +{ > + struct amd_cpudata *cpudata = policy->driver_data; > + > + if (power_supply_is_system_supplied()) > + return cpudata->epp_default_ac; > + else > + return cpudata->epp_default_dc; > +} > + > +static int amd_pstate_power_supply_notifier(struct notifier_block *nb, > + unsigned long event, void *data) > +{ > + struct amd_cpudata *cpudata = container_of(nb, struct amd_cpudata, power_nb); > + struct cpufreq_policy *policy __free(put_cpufreq_policy) = cpufreq_cpu_get(cpudata->cpu); > + u8 epp; > + int ret; > + > + if (event != PSY_EVENT_PROP_CHANGED) > + return NOTIFY_OK; > + > + epp = amd_pstate_get_balanced_epp(policy); > + > + ret = amd_pstate_set_epp(policy, epp); > + if (ret) > + pr_warn("Failed to set CPU %d EPP %u: %d\n", cpudata->cpu, epp, ret); > + > + return NOTIFY_OK; > +} > +static void amd_pstate_clear_dynamic_epp(struct cpufreq_policy *policy) > +{ > + struct amd_cpudata *cpudata = policy->driver_data; > + > + if (cpudata->power_nb.notifier_call) > + power_supply_unreg_notifier(&cpudata->power_nb); > + cpudata->dynamic_epp = false; > +} > + > +static int amd_pstate_set_dynamic_epp(struct cpufreq_policy *policy) > +{ > + struct amd_cpudata *cpudata = policy->driver_data; > + int ret; > + u8 epp; > + > + epp = amd_pstate_get_balanced_epp(policy); > + ret = amd_pstate_set_epp(policy, epp); > + if (ret) > + return ret; > + > + /* only enable notifier if things will actually change */ > + if (cpudata->epp_default_ac != cpudata->epp_default_dc) { > + ret = power_supply_reg_notifier(&cpudata->power_nb); > + if (ret) > + goto cleanup; > + cpudata->power_nb.notifier_call = amd_pstate_power_supply_notifier; > + } > + > + cpudata->dynamic_epp = true; > + > + return 0; > + > +cleanup: > + amd_pstate_clear_dynamic_epp(policy); > + > + return ret; > +} > + > /* Sysfs attributes */ > > /* > @@ -1146,6 +1215,11 @@ static ssize_t store_energy_performance_preference( > ssize_t ret; > u8 epp; > > + if (cpudata->dynamic_epp) { > + pr_debug("EPP cannot be set when dynamic EPP is enabled\n"); > + return -EBUSY; > + } > + > ret = sscanf(buf, "%20s", str_preference); > if (ret != 1) > return -EINVAL; > @@ -1154,10 +1228,10 @@ static ssize_t store_energy_performance_preference( > if (ret < 0) > return -EINVAL; > > - if (!ret) > - epp = cpudata->epp_default; > - else > + if (ret) > epp = epp_values[ret]; > + else > + epp = amd_pstate_get_balanced_epp(policy); > > if (epp > 0 && policy->policy == CPUFREQ_POLICY_PERFORMANCE) { > pr_debug("EPP cannot be set under performance policy\n"); > @@ -1165,6 +1239,8 @@ static ssize_t store_energy_performance_preference( > } > > ret = amd_pstate_set_epp(policy, epp); > + if (ret) > + return ret; Isn't this unecessary given that the next line is doing exactly this ? > > return ret ? ret : count; > } Rest of the patch looks good to me.
On 3/4/2025 8:53 PM, Mario Limonciello wrote: > From: Mario Limonciello <mario.limonciello@amd.com> > > Dynamic energy performance preference will change the EPP profile > based on whether the machine is running on AC or DC power. > > A notification chain from the power supply core is used to adjust > EPP values on plug in or plug out events. > > For non-server systems: > * the default EPP for AC mode is `performance`. > * the default EPP for DC mode is `balance_performance`. > > Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> > --- > v1->v2: > * Change defaults to performance (AC) and balance_performance (DC) > * Default Kconfig to disabled for now > * Rebase on latest branch > --- > Documentation/admin-guide/pm/amd-pstate.rst | 18 ++- > drivers/cpufreq/Kconfig.x86 | 12 ++ > drivers/cpufreq/amd-pstate.c | 129 ++++++++++++++++++-- > drivers/cpufreq/amd-pstate.h | 5 +- > 4 files changed, 155 insertions(+), 9 deletions(-) > [Snip] > diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c > index e98ef41083ba1..f00fb4ba9f26e 100644 > --- a/drivers/cpufreq/amd-pstate.c > +++ b/drivers/cpufreq/amd-pstate.c > @@ -36,6 +36,7 @@ > #include <linux/io.h> > #include <linux/delay.h> > #include <linux/uaccess.h> > +#include <linux/power_supply.h> > #include <linux/static_call.h> > #include <linux/topology.h> > > @@ -86,6 +87,7 @@ static struct cpufreq_driver amd_pstate_driver; > static struct cpufreq_driver amd_pstate_epp_driver; > static int cppc_state = AMD_PSTATE_UNDEFINED; > static bool amd_pstate_prefcore = true; > +static bool dynamic_epp = CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP; Is there an #ifdef needed here? I see build error when X86_AMD_PSTATE_DYNAMIC_EPP is not set in config
On 3/4/2025 8:53 PM, Mario Limonciello wrote: > From: Mario Limonciello <mario.limonciello@amd.com> > > Dynamic energy performance preference will change the EPP profile > based on whether the machine is running on AC or DC power. > > A notification chain from the power supply core is used to adjust > EPP values on plug in or plug out events. > > For non-server systems: > * the default EPP for AC mode is `performance`. > * the default EPP for DC mode is `balance_performance`. > > Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> > --- > v1->v2: > * Change defaults to performance (AC) and balance_performance (DC) > * Default Kconfig to disabled for now > * Rebase on latest branch > --- > Documentation/admin-guide/pm/amd-pstate.rst | 18 ++- > drivers/cpufreq/Kconfig.x86 | 12 ++ > drivers/cpufreq/amd-pstate.c | 129 ++++++++++++++++++-- > drivers/cpufreq/amd-pstate.h | 5 +- > 4 files changed, 155 insertions(+), 9 deletions(-) > [Snip] > @@ -1556,6 +1667,10 @@ static int amd_pstate_epp_set_policy(struct cpufreq_policy *policy) > if (!policy->cpuinfo.max_freq) > return -ENODEV; > > + /* policy can't be changed to performance policy while dynamic epp is enabled */ > + if (policy->policy == CPUFREQ_POLICY_PERFORMANCE && cpudata->dynamic_epp) > + return -EBUSY; We might need to tweak this condition, because if we enable "CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP" in config and boot with "amd_pstate=active" it lands here (cpufreq_online()->amd_pstate_epp_set_policy()) driver init fails as the default governor is performance. > + > cpudata->policy = policy->policy; > > ret = amd_pstate_epp_update_limit(policy); > diff --git a/drivers/cpufreq/amd-pstate.h b/drivers/cpufreq/amd-pstate.h > index fbe1c08d3f061..6882876f895de 100644 > --- a/drivers/cpufreq/amd-pstate.h > +++ b/drivers/cpufreq/amd-pstate.h > @@ -104,7 +104,10 @@ struct amd_cpudata { > /* EPP feature related attributes*/ > u32 policy; > bool suspended; > - u8 epp_default; > + u8 epp_default_ac; > + u8 epp_default_dc; > + bool dynamic_epp; > + struct notifier_block power_nb; > }; > > /*
diff --git a/Documentation/admin-guide/pm/amd-pstate.rst b/Documentation/admin-guide/pm/amd-pstate.rst index 412423c54f258..2e076650dc77c 100644 --- a/Documentation/admin-guide/pm/amd-pstate.rst +++ b/Documentation/admin-guide/pm/amd-pstate.rst @@ -289,7 +289,7 @@ and user can change current preference according to energy or performance needs Please get all support profiles list from ``energy_performance_available_preferences`` attribute, all the profiles are integer values defined between 0 to 255 when EPP feature is enabled by platform -firmware, if EPP feature is disabled, driver will ignore the written value +firmware, but if the dynamic EPP feature is enabled, driver will block writes. This attribute is read-write. ``boost`` @@ -311,6 +311,22 @@ boost or `1` to enable it, for the respective CPU using the sysfs path Other performance and frequency values can be read back from ``/sys/devices/system/cpu/cpuX/acpi_cppc/``, see :ref:`cppc_sysfs`. +Dynamic energy performance profile +================================== +The amd-pstate driver supports dynamically selecting the energy performance +profile based on whether the machine is running on AC or DC power. + +Whether this behavior is enabled by default with the kernel config option +`CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP`. This behavior can also be overridden +at runtime by the sysfs file ``/sys/devices/system/cpu/cpufreq/policyX/dynamic_epp``. + +When set to enabled, the driver will select a different energy performance +profile when the machine is running on battery or AC power. +When set to disabled, the driver will not change the energy performance profile +based on the power source and will not react to user desired power state. + +Attempting to manually write to the ``energy_performance_preference`` sysfs +file will fail when ``dynamic_epp`` is enabled. ``amd-pstate`` vs ``acpi-cpufreq`` ====================================== diff --git a/drivers/cpufreq/Kconfig.x86 b/drivers/cpufreq/Kconfig.x86 index 97c2d4f15d76e..c5ef92634ddf4 100644 --- a/drivers/cpufreq/Kconfig.x86 +++ b/drivers/cpufreq/Kconfig.x86 @@ -68,6 +68,18 @@ config X86_AMD_PSTATE_DEFAULT_MODE For details, take a look at: <file:Documentation/admin-guide/pm/amd-pstate.rst>. +config X86_AMD_PSTATE_DYNAMIC_EPP + bool "AMD Processor P-State dynamic EPP support" + depends on X86_AMD_PSTATE + default n + help + Allow the kenrel to dynamically change the energy performance + value from events like ACPI platform profile and AC adapter plug + events. + + This feature can also be changed at runtime, this configuration + option only sets the kernel default value behavior. + config X86_AMD_PSTATE_UT tristate "selftest for AMD Processor P-State driver" depends on X86 && ACPI_PROCESSOR diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c index e98ef41083ba1..f00fb4ba9f26e 100644 --- a/drivers/cpufreq/amd-pstate.c +++ b/drivers/cpufreq/amd-pstate.c @@ -36,6 +36,7 @@ #include <linux/io.h> #include <linux/delay.h> #include <linux/uaccess.h> +#include <linux/power_supply.h> #include <linux/static_call.h> #include <linux/topology.h> @@ -86,6 +87,7 @@ static struct cpufreq_driver amd_pstate_driver; static struct cpufreq_driver amd_pstate_epp_driver; static int cppc_state = AMD_PSTATE_UNDEFINED; static bool amd_pstate_prefcore = true; +static bool dynamic_epp = CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP; static struct quirk_entry *quirks; /* @@ -1050,6 +1052,73 @@ static void amd_pstate_cpu_exit(struct cpufreq_policy *policy) kfree(cpudata); } +static int amd_pstate_get_balanced_epp(struct cpufreq_policy *policy) +{ + struct amd_cpudata *cpudata = policy->driver_data; + + if (power_supply_is_system_supplied()) + return cpudata->epp_default_ac; + else + return cpudata->epp_default_dc; +} + +static int amd_pstate_power_supply_notifier(struct notifier_block *nb, + unsigned long event, void *data) +{ + struct amd_cpudata *cpudata = container_of(nb, struct amd_cpudata, power_nb); + struct cpufreq_policy *policy __free(put_cpufreq_policy) = cpufreq_cpu_get(cpudata->cpu); + u8 epp; + int ret; + + if (event != PSY_EVENT_PROP_CHANGED) + return NOTIFY_OK; + + epp = amd_pstate_get_balanced_epp(policy); + + ret = amd_pstate_set_epp(policy, epp); + if (ret) + pr_warn("Failed to set CPU %d EPP %u: %d\n", cpudata->cpu, epp, ret); + + return NOTIFY_OK; +} +static void amd_pstate_clear_dynamic_epp(struct cpufreq_policy *policy) +{ + struct amd_cpudata *cpudata = policy->driver_data; + + if (cpudata->power_nb.notifier_call) + power_supply_unreg_notifier(&cpudata->power_nb); + cpudata->dynamic_epp = false; +} + +static int amd_pstate_set_dynamic_epp(struct cpufreq_policy *policy) +{ + struct amd_cpudata *cpudata = policy->driver_data; + int ret; + u8 epp; + + epp = amd_pstate_get_balanced_epp(policy); + ret = amd_pstate_set_epp(policy, epp); + if (ret) + return ret; + + /* only enable notifier if things will actually change */ + if (cpudata->epp_default_ac != cpudata->epp_default_dc) { + ret = power_supply_reg_notifier(&cpudata->power_nb); + if (ret) + goto cleanup; + cpudata->power_nb.notifier_call = amd_pstate_power_supply_notifier; + } + + cpudata->dynamic_epp = true; + + return 0; + +cleanup: + amd_pstate_clear_dynamic_epp(policy); + + return ret; +} + /* Sysfs attributes */ /* @@ -1146,6 +1215,11 @@ static ssize_t store_energy_performance_preference( ssize_t ret; u8 epp; + if (cpudata->dynamic_epp) { + pr_debug("EPP cannot be set when dynamic EPP is enabled\n"); + return -EBUSY; + } + ret = sscanf(buf, "%20s", str_preference); if (ret != 1) return -EINVAL; @@ -1154,10 +1228,10 @@ static ssize_t store_energy_performance_preference( if (ret < 0) return -EINVAL; - if (!ret) - epp = cpudata->epp_default; - else + if (ret) epp = epp_values[ret]; + else + epp = amd_pstate_get_balanced_epp(policy); if (epp > 0 && policy->policy == CPUFREQ_POLICY_PERFORMANCE) { pr_debug("EPP cannot be set under performance policy\n"); @@ -1165,6 +1239,8 @@ static ssize_t store_energy_performance_preference( } ret = amd_pstate_set_epp(policy, epp); + if (ret) + return ret; return ret ? ret : count; } @@ -1364,6 +1440,32 @@ static ssize_t prefcore_show(struct device *dev, return sysfs_emit(buf, "%s\n", str_enabled_disabled(amd_pstate_prefcore)); } +static ssize_t dynamic_epp_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sysfs_emit(buf, "%s\n", str_enabled_disabled(dynamic_epp)); +} + +static ssize_t dynamic_epp_store(struct device *a, struct device_attribute *b, + const char *buf, size_t count) +{ + bool enabled; + int ret; + + ret = kstrtobool(buf, &enabled); + if (ret) + return ret; + + if (dynamic_epp == enabled) + return -EINVAL; + + /* reinitialize with desired dynamic EPP value */ + dynamic_epp = enabled; + ret = amd_pstate_change_driver_mode(cppc_state); + + return ret ? ret : count; +} + cpufreq_freq_attr_ro(amd_pstate_max_freq); cpufreq_freq_attr_ro(amd_pstate_lowest_nonlinear_freq); @@ -1374,6 +1476,7 @@ cpufreq_freq_attr_rw(energy_performance_preference); cpufreq_freq_attr_ro(energy_performance_available_preferences); static DEVICE_ATTR_RW(status); static DEVICE_ATTR_RO(prefcore); +static DEVICE_ATTR_RW(dynamic_epp); static struct freq_attr *amd_pstate_attr[] = { &amd_pstate_max_freq, @@ -1398,6 +1501,7 @@ static struct freq_attr *amd_pstate_epp_attr[] = { static struct attribute *pstate_global_attributes[] = { &dev_attr_status.attr, &dev_attr_prefcore.attr, + &dev_attr_dynamic_epp.attr, NULL }; @@ -1490,10 +1594,11 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy) if (amd_pstate_acpi_pm_profile_server() || amd_pstate_acpi_pm_profile_undefined()) { policy->policy = CPUFREQ_POLICY_PERFORMANCE; - cpudata->epp_default = amd_pstate_get_epp(cpudata); + cpudata->epp_default_ac = cpudata->epp_default_dc = amd_pstate_get_epp(cpudata); } else { policy->policy = CPUFREQ_POLICY_POWERSAVE; - cpudata->epp_default = AMD_CPPC_EPP_BALANCE_PERFORMANCE; + cpudata->epp_default_ac = AMD_CPPC_EPP_PERFORMANCE; + cpudata->epp_default_dc = AMD_CPPC_EPP_BALANCE_PERFORMANCE; } if (cpu_feature_enabled(X86_FEATURE_CPPC)) { @@ -1502,9 +1607,13 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy) return ret; WRITE_ONCE(cpudata->cppc_req_cached, value); } - ret = amd_pstate_set_epp(policy, cpudata->epp_default); + + if (dynamic_epp) + ret = amd_pstate_set_dynamic_epp(policy); + else + ret = amd_pstate_set_epp(policy, amd_pstate_get_balanced_epp(policy)); if (ret) - return ret; + goto free_cpudata1; current_pstate_driver->adjust_perf = NULL; @@ -1521,6 +1630,8 @@ static void amd_pstate_epp_cpu_exit(struct cpufreq_policy *policy) struct amd_cpudata *cpudata = policy->driver_data; if (cpudata) { + if (cpudata->dynamic_epp) + amd_pstate_clear_dynamic_epp(policy); kfree(cpudata); policy->driver_data = NULL; } @@ -1556,6 +1667,10 @@ static int amd_pstate_epp_set_policy(struct cpufreq_policy *policy) if (!policy->cpuinfo.max_freq) return -ENODEV; + /* policy can't be changed to performance policy while dynamic epp is enabled */ + if (policy->policy == CPUFREQ_POLICY_PERFORMANCE && cpudata->dynamic_epp) + return -EBUSY; + cpudata->policy = policy->policy; ret = amd_pstate_epp_update_limit(policy); diff --git a/drivers/cpufreq/amd-pstate.h b/drivers/cpufreq/amd-pstate.h index fbe1c08d3f061..6882876f895de 100644 --- a/drivers/cpufreq/amd-pstate.h +++ b/drivers/cpufreq/amd-pstate.h @@ -104,7 +104,10 @@ struct amd_cpudata { /* EPP feature related attributes*/ u32 policy; bool suspended; - u8 epp_default; + u8 epp_default_ac; + u8 epp_default_dc; + bool dynamic_epp; + struct notifier_block power_nb; }; /*