[PATCH] cpufreq: amd-pstate: Add sysfs file for base frequency

[PATCH] cpufreq: amd-pstate: Add sysfs file for base frequency

[Mario Limonciello]

Some applications may want to query the base frequency to tell when
a processor is operating in boost.

Tested-by: Wyes Karny <wyes.karny@amd.com>
Reviewed-by: Wyes Karny <wyes.karny@amd.com>
Co-developed-by: Perry Yuan <perry.yuan@amd.com>
Signed-off-by: Perry Yuan <perry.yuan@amd.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
---
 Documentation/admin-guide/pm/amd-pstate.rst |  4 ++++
 drivers/cpufreq/amd-pstate.c                | 15 +++++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/Documentation/admin-guide/pm/amd-pstate.rst b/Documentation/admin-guide/pm/amd-pstate.rst
index 1cf40f69278cd..e68267857e859 100644
--- a/Documentation/admin-guide/pm/amd-pstate.rst
+++ b/Documentation/admin-guide/pm/amd-pstate.rst
@@ -281,6 +281,10 @@ 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
 This attribute is read-write.
 
+``base_frequency``
+	Shows the base frequency of the CPU. Frequencies above this will be in the
+  ``boost`` range. This attribute is read-only.
+
 Other performance and frequency values can be read back from
 ``/sys/devices/system/cpu/cpuX/acpi_cppc/``, see :ref:`cppc_sysfs`.
 
diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index 81fba0dcbee99..0fec66b3f7241 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -1037,6 +1037,19 @@ static ssize_t store_status(struct kobject *a, struct kobj_attribute *b,
 	return ret < 0 ? ret : count;
 }
 
+static ssize_t show_base_frequency(struct cpufreq_policy *policy, char *buf)
+{
+	struct amd_cpudata *cpudata = policy->driver_data;
+	u32 nominal_freq;
+
+	nominal_freq = amd_get_nominal_freq(cpudata);
+	if (nominal_freq < 0)
+		return nominal_freq;
+
+	return sysfs_emit(buf, "%d\n", nominal_freq);
+}
+
+cpufreq_freq_attr_ro(base_frequency);
 cpufreq_freq_attr_ro(amd_pstate_max_freq);
 cpufreq_freq_attr_ro(amd_pstate_lowest_nonlinear_freq);
 
@@ -1049,6 +1062,7 @@ static struct freq_attr *amd_pstate_attr[] = {
 	&amd_pstate_max_freq,
 	&amd_pstate_lowest_nonlinear_freq,
 	&amd_pstate_highest_perf,
+	&base_frequency,
 	NULL,
 };
 
@@ -1058,6 +1072,7 @@ static struct freq_attr *amd_pstate_epp_attr[] = {
 	&amd_pstate_highest_perf,
 	&energy_performance_preference,
 	&energy_performance_available_preferences,
+	&base_frequency,
 	NULL,
 };
 
-- 
2.34.1

Re: [PATCH] cpufreq: amd-pstate: Add sysfs file for base frequency

[Huang Rui]

On Thu, Jun 29, 2023 at 09:54:54PM +0800, Limonciello, Mario wrote:
> Some applications may want to query the base frequency to tell when
> a processor is operating in boost.
> 
> Tested-by: Wyes Karny <wyes.karny@amd.com>
> Reviewed-by: Wyes Karny <wyes.karny@amd.com>
> Co-developed-by: Perry Yuan <perry.yuan@amd.com>
> Signed-off-by: Perry Yuan <perry.yuan@amd.com>
> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
> ---
>  Documentation/admin-guide/pm/amd-pstate.rst |  4 ++++
>  drivers/cpufreq/amd-pstate.c                | 15 +++++++++++++++
>  2 files changed, 19 insertions(+)
> 
> diff --git a/Documentation/admin-guide/pm/amd-pstate.rst b/Documentation/admin-guide/pm/amd-pstate.rst
> index 1cf40f69278cd..e68267857e859 100644
> --- a/Documentation/admin-guide/pm/amd-pstate.rst
> +++ b/Documentation/admin-guide/pm/amd-pstate.rst
> @@ -281,6 +281,10 @@ 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
>  This attribute is read-write.
>  
> +``base_frequency``
> +	Shows the base frequency of the CPU. Frequencies above this will be in the
> +  ``boost`` range. This attribute is read-only.
> +
>  Other performance and frequency values can be read back from
>  ``/sys/devices/system/cpu/cpuX/acpi_cppc/``, see :ref:`cppc_sysfs`.
>  
> diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
> index 81fba0dcbee99..0fec66b3f7241 100644
> --- a/drivers/cpufreq/amd-pstate.c
> +++ b/drivers/cpufreq/amd-pstate.c
> @@ -1037,6 +1037,19 @@ static ssize_t store_status(struct kobject *a, struct kobj_attribute *b,
>  	return ret < 0 ? ret : count;
>  }
>  
> +static ssize_t show_base_frequency(struct cpufreq_policy *policy, char *buf)
> +{
> +	struct amd_cpudata *cpudata = policy->driver_data;
> +	u32 nominal_freq;
> +
> +	nominal_freq = amd_get_nominal_freq(cpudata);
> +	if (nominal_freq < 0)
> +		return nominal_freq;
> +
> +	return sysfs_emit(buf, "%d\n", nominal_freq);
> +}

User can get it from nominal_freq at drivers/acpi/cppc_acpi.c:

show_cppc_data(cppc_get_perf_caps, cppc_perf_caps, nominal_freq);

Thanks,
Ray

> +
> +cpufreq_freq_attr_ro(base_frequency);
>  cpufreq_freq_attr_ro(amd_pstate_max_freq);
>  cpufreq_freq_attr_ro(amd_pstate_lowest_nonlinear_freq);
>  
> @@ -1049,6 +1062,7 @@ static struct freq_attr *amd_pstate_attr[] = {
>  	&amd_pstate_max_freq,
>  	&amd_pstate_lowest_nonlinear_freq,
>  	&amd_pstate_highest_perf,
> +	&base_frequency,
>  	NULL,
>  };
>  
> @@ -1058,6 +1072,7 @@ static struct freq_attr *amd_pstate_epp_attr[] = {
>  	&amd_pstate_highest_perf,
>  	&energy_performance_preference,
>  	&energy_performance_available_preferences,
> +	&base_frequency,
>  	NULL,
>  };
>  
> -- 
> 2.34.1
> 

Re: [PATCH] cpufreq: amd-pstate: Add sysfs file for base frequency

[Mario Limonciello]

On 7/3/23 02:06, Huang Rui wrote:
> On Thu, Jun 29, 2023 at 09:54:54PM +0800, Limonciello, Mario wrote:
>> Some applications may want to query the base frequency to tell when
>> a processor is operating in boost.
>>
>> Tested-by: Wyes Karny <wyes.karny@amd.com>
>> Reviewed-by: Wyes Karny <wyes.karny@amd.com>
>> Co-developed-by: Perry Yuan <perry.yuan@amd.com>
>> Signed-off-by: Perry Yuan <perry.yuan@amd.com>
>> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
>> ---
>>   Documentation/admin-guide/pm/amd-pstate.rst |  4 ++++
>>   drivers/cpufreq/amd-pstate.c                | 15 +++++++++++++++
>>   2 files changed, 19 insertions(+)
>>
>> diff --git a/Documentation/admin-guide/pm/amd-pstate.rst b/Documentation/admin-guide/pm/amd-pstate.rst
>> index 1cf40f69278cd..e68267857e859 100644
>> --- a/Documentation/admin-guide/pm/amd-pstate.rst
>> +++ b/Documentation/admin-guide/pm/amd-pstate.rst
>> @@ -281,6 +281,10 @@ 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
>>   This attribute is read-write.
>>   
>> +``base_frequency``
>> +	Shows the base frequency of the CPU. Frequencies above this will be in the
>> +  ``boost`` range. This attribute is read-only.
>> +
>>   Other performance and frequency values can be read back from
>>   ``/sys/devices/system/cpu/cpuX/acpi_cppc/``, see :ref:`cppc_sysfs`.
>>   
>> diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
>> index 81fba0dcbee99..0fec66b3f7241 100644
>> --- a/drivers/cpufreq/amd-pstate.c
>> +++ b/drivers/cpufreq/amd-pstate.c
>> @@ -1037,6 +1037,19 @@ static ssize_t store_status(struct kobject *a, struct kobj_attribute *b,
>>   	return ret < 0 ? ret : count;
>>   }
>>   
>> +static ssize_t show_base_frequency(struct cpufreq_policy *policy, char *buf)
>> +{
>> +	struct amd_cpudata *cpudata = policy->driver_data;
>> +	u32 nominal_freq;
>> +
>> +	nominal_freq = amd_get_nominal_freq(cpudata);
>> +	if (nominal_freq < 0)
>> +		return nominal_freq;
>> +
>> +	return sysfs_emit(buf, "%d\n", nominal_freq);
>> +}
> 
> User can get it from nominal_freq at drivers/acpi/cppc_acpi.c:
> 
> show_cppc_data(cppc_get_perf_caps, cppc_perf_caps, nominal_freq);

Thanks for sharing that, I wasn't aware.  This patch is unnecessary indeed.

> 
> Thanks,
> Ray
> 
>> +
>> +cpufreq_freq_attr_ro(base_frequency);
>>   cpufreq_freq_attr_ro(amd_pstate_max_freq);
>>   cpufreq_freq_attr_ro(amd_pstate_lowest_nonlinear_freq);
>>   
>> @@ -1049,6 +1062,7 @@ static struct freq_attr *amd_pstate_attr[] = {
>>   	&amd_pstate_max_freq,
>>   	&amd_pstate_lowest_nonlinear_freq,
>>   	&amd_pstate_highest_perf,
>> +	&base_frequency,
>>   	NULL,
>>   };
>>   
>> @@ -1058,6 +1072,7 @@ static struct freq_attr *amd_pstate_epp_attr[] = {
>>   	&amd_pstate_highest_perf,
>>   	&energy_performance_preference,
>>   	&energy_performance_available_preferences,
>> +	&base_frequency,
>>   	NULL,
>>   };
>>   
>> -- 
>> 2.34.1
>>

Re: [PATCH] cpufreq: amd-pstate: Add sysfs file for base frequency

[kernel test robot]

Hi Mario,

kernel test robot noticed the following build warnings:

[auto build test WARNING on rafael-pm/linux-next]
[also build test WARNING on linus/master v6.5-rc1 next-20230711]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Mario-Limonciello/cpufreq-amd-pstate-Add-sysfs-file-for-base-frequency/20230630-203900
base:   https://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git linux-next
patch link:    https://lore.kernel.org/r/20230629135454.177421-1-mario.limonciello%40amd.com
patch subject: [PATCH] cpufreq: amd-pstate: Add sysfs file for base frequency
reproduce: (https://download.01.org/0day-ci/archive/20230711/202307111214.8H56UUiU-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202307111214.8H56UUiU-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> Documentation/admin-guide/pm/amd-pstate.rst:286: WARNING: Block quote ends without a blank line; unexpected unindent.

vim +286 Documentation/admin-guide/pm/amd-pstate.rst

   283	
   284	``base_frequency``
   285		Shows the base frequency of the CPU. Frequencies above this will be in the
 > 286	  ``boost`` range. This attribute is read-only.
   287	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki