2022-12-07 16:23:27

by Wyes Karny

[permalink] [raw]
Subject: [PATCH 4/4] Documentation: amd_pstate: Add amd_pstate state sysfs file

Add documentation for amd_pstate `state` interface.
User can see the current state of the driver with the help of this sysfs
interface:
# cat /sys/devices/system/cpu/amd_pstate/state
# disable [passive] guided

User can load/unload driver with the help of `state` sysfs interface.
- Load driver with passive mode:
# echo passive > /sys/devices/system/cpu/amd_pstate/state
- Unload the driver:
# echo disable > /sys/devices/system/cpu/amd_pstate/state
- To switch to guided mode:
# echo guided > /sys/devices/system/cpu/amd_pstate/state

Signed-off-by: Wyes Karny <[email protected]>
---
Documentation/admin-guide/pm/amd-pstate.rst | 11 +++++++++++
1 file changed, 11 insertions(+)

diff --git a/Documentation/admin-guide/pm/amd-pstate.rst b/Documentation/admin-guide/pm/amd-pstate.rst
index 06e23538f79c..4d3783516ddc 100644
--- a/Documentation/admin-guide/pm/amd-pstate.rst
+++ b/Documentation/admin-guide/pm/amd-pstate.rst
@@ -265,6 +265,17 @@ 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`.

+``state``
+
+``amd_pstate`` also exposes a sysfs interface to view and control the driver state.
+The driver state can be one of the following:
+``disable`` : indicates driver is in unloaded state.
+``passive`` : indicates driver is loaded and currently in passive mode.
+``guided`` : indicates driver is loaded and currenlty in guided autonomous mode.
+This file can be found here: ``/sys/devices/system/cpu/amd_pstate/state``.
+
+To switch to passive mode: ``echo passive > /sys/devices/system/cpu/amd_pstate/state``
+To switch to guided mode: ``echo guided > /sys/devices/system/cpu/amd_pstate/state``

``amd-pstate`` vs ``acpi-cpufreq``
======================================
--
2.34.1


2022-12-08 03:50:42

by Bagas Sanjaya

[permalink] [raw]
Subject: Re: [PATCH 4/4] Documentation: amd_pstate: Add amd_pstate state sysfs file

On Wed, Dec 07, 2022 at 03:46:48PM +0000, Wyes Karny wrote:
> +``state``
> +
> +``amd_pstate`` also exposes a sysfs interface to view and control the driver state.
> +The driver state can be one of the following:
> +``disable`` : indicates driver is in unloaded state.
> +``passive`` : indicates driver is loaded and currently in passive mode.
> +``guided`` : indicates driver is loaded and currenlty in guided autonomous mode.

Use bullet lists for above:

---- >8 ----

diff --git a/Documentation/admin-guide/pm/amd-pstate.rst b/Documentation/admin-guide/pm/amd-pstate.rst
index 4d3783516ddc2c..0d0e0affa3adb2 100644
--- a/Documentation/admin-guide/pm/amd-pstate.rst
+++ b/Documentation/admin-guide/pm/amd-pstate.rst
@@ -269,9 +269,12 @@ Other performance and frequency values can be read back from

``amd_pstate`` also exposes a sysfs interface to view and control the driver state.
The driver state can be one of the following:
-``disable`` : indicates driver is in unloaded state.
-``passive`` : indicates driver is loaded and currently in passive mode.
-``guided`` : indicates driver is loaded and currenlty in guided autonomous mode.
+
+ - ``disable`` : indicates driver is in unloaded state.
+ - ``passive`` : indicates driver is loaded and currently in passive mode.
+ - ``guided`` : indicates driver is loaded and currenlty in guided
+ autonomous mode.
+
This file can be found here: ``/sys/devices/system/cpu/amd_pstate/state``.

To switch to passive mode: ``echo passive > /sys/devices/system/cpu/amd_pstate/state``

> +This file can be found here: ``/sys/devices/system/cpu/amd_pstate/state``.
> +
> +To switch to passive mode: ``echo passive > /sys/devices/system/cpu/amd_pstate/state``
> +To switch to guided mode: ``echo guided > /sys/devices/system/cpu/amd_pstate/state``
>

What about these wordings instead?

---- >8 ----

diff --git a/Documentation/admin-guide/pm/amd-pstate.rst b/Documentation/admin-guide/pm/amd-pstate.rst
index 4d3783516ddc2c..6465bd39b7dcbc 100644
--- a/Documentation/admin-guide/pm/amd-pstate.rst
+++ b/Documentation/admin-guide/pm/amd-pstate.rst
@@ -267,15 +267,16 @@ Other performance and frequency values can be read back from

``state``

-``amd_pstate`` also exposes a sysfs interface to view and control the driver state.
-The driver state can be one of the following:
-``disable`` : indicates driver is in unloaded state.
-``passive`` : indicates driver is loaded and currently in passive mode.
-``guided`` : indicates driver is loaded and currenlty in guided autonomous mode.
-This file can be found here: ``/sys/devices/system/cpu/amd_pstate/state``.
+``amd_pstate`` also exposes a sysfs interface to view and control the driver
+state, named ``/sys/devices/system/cpu/amd_pstate/state``. The driver state
+can be one of the following:

-To switch to passive mode: ``echo passive > /sys/devices/system/cpu/amd_pstate/state``
-To switch to guided mode: ``echo guided > /sys/devices/system/cpu/amd_pstate/state``
+ - ``disable`` : the driver is disabled
+ - ``passive`` : the driver is in passive mode.
+ - ``guided`` : the driver is in guided autonomous mode.
+
+To switch between these modes above, write the appropriate value to the
+aforementioned sysfs file.

``amd-pstate`` vs ``acpi-cpufreq``
======================================

Thanks.

--
An old man doll... just what I always wanted! - Clara


Attachments:
(No filename) (3.43 kB)
signature.asc (235.00 B)
Download all attachments

2022-12-09 09:34:49

by Wyes Karny

[permalink] [raw]
Subject: Re: [PATCH 4/4] Documentation: amd_pstate: Add amd_pstate state sysfs file



On 12/8/2022 8:29 AM, Bagas Sanjaya wrote:
> On Wed, Dec 07, 2022 at 03:46:48PM +0000, Wyes Karny wrote:
>> +``state``
>> +
>> +``amd_pstate`` also exposes a sysfs interface to view and control the driver state.
>> +The driver state can be one of the following:
>> +``disable`` : indicates driver is in unloaded state.
>> +``passive`` : indicates driver is loaded and currently in passive mode.
>> +``guided`` : indicates driver is loaded and currenlty in guided autonomous mode.
>
> Use bullet lists for above:
>
> ---- >8 ----
>
> diff --git a/Documentation/admin-guide/pm/amd-pstate.rst b/Documentation/admin-guide/pm/amd-pstate.rst
> index 4d3783516ddc2c..0d0e0affa3adb2 100644
> --- a/Documentation/admin-guide/pm/amd-pstate.rst
> +++ b/Documentation/admin-guide/pm/amd-pstate.rst
> @@ -269,9 +269,12 @@ Other performance and frequency values can be read back from
>
> ``amd_pstate`` also exposes a sysfs interface to view and control the driver state.
> The driver state can be one of the following:
> -``disable`` : indicates driver is in unloaded state.
> -``passive`` : indicates driver is loaded and currently in passive mode.
> -``guided`` : indicates driver is loaded and currenlty in guided autonomous mode.
> +
> + - ``disable`` : indicates driver is in unloaded state.
> + - ``passive`` : indicates driver is loaded and currently in passive mode.
> + - ``guided`` : indicates driver is loaded and currenlty in guided
> + autonomous mode.
> +
> This file can be found here: ``/sys/devices/system/cpu/amd_pstate/state``.
>
> To switch to passive mode: ``echo passive > /sys/devices/system/cpu/amd_pstate/state``
>
>> +This file can be found here: ``/sys/devices/system/cpu/amd_pstate/state``.
>> +
>> +To switch to passive mode: ``echo passive > /sys/devices/system/cpu/amd_pstate/state``
>> +To switch to guided mode: ``echo guided > /sys/devices/system/cpu/amd_pstate/state``
>>
>
> What about these wordings instead?
>
> ---- >8 ----
>
> diff --git a/Documentation/admin-guide/pm/amd-pstate.rst b/Documentation/admin-guide/pm/amd-pstate.rst
> index 4d3783516ddc2c..6465bd39b7dcbc 100644
> --- a/Documentation/admin-guide/pm/amd-pstate.rst
> +++ b/Documentation/admin-guide/pm/amd-pstate.rst
> @@ -267,15 +267,16 @@ Other performance and frequency values can be read back from
>
> ``state``
>
> -``amd_pstate`` also exposes a sysfs interface to view and control the driver state.
> -The driver state can be one of the following:
> -``disable`` : indicates driver is in unloaded state.
> -``passive`` : indicates driver is loaded and currently in passive mode.
> -``guided`` : indicates driver is loaded and currenlty in guided autonomous mode.
> -This file can be found here: ``/sys/devices/system/cpu/amd_pstate/state``.
> +``amd_pstate`` also exposes a sysfs interface to view and control the driver
> +state, named ``/sys/devices/system/cpu/amd_pstate/state``. The driver state
> +can be one of the following:
>
> -To switch to passive mode: ``echo passive > /sys/devices/system/cpu/amd_pstate/state``
> -To switch to guided mode: ``echo guided > /sys/devices/system/cpu/amd_pstate/state``
> + - ``disable`` : the driver is disabled
> + - ``passive`` : the driver is in passive mode.
> + - ``guided`` : the driver is in guided autonomous mode.
> +
> +To switch between these modes above, write the appropriate value to the
> +aforementioned sysfs file.

LGTM. I'll reword. Thanks!

>
> ``amd-pstate`` vs ``acpi-cpufreq``
> ======================================
>
> Thanks.
>

--
Thanks & Regards,
Wyes