diff mbox series

[v4,9/9] Documentation: amd-pstate: add amd pstate driver mode introduction

Message ID 20221110175847.3098728-10-Perry.Yuan@amd.com
State New
Headers
Series Implement AMD Pstate EPP Driver |

Commit Message

Yuan, Perry Nov. 10, 2022, 5:58 p.m. UTC 
  Introduce ``amd-pstate`` CPPC has two operation modes:
* CPPC Autonomous (active) mode
* CPPC non-autonomous (passive) mode.
active mode and passive mode can be choosed by whith different kernel parameters.

Signed-off-by: Perry Yuan <Perry.Yuan@amd.com>
---
 Documentation/admin-guide/pm/amd-pstate.rst | 47 +++++++++++++++++++--
 1 file changed, 43 insertions(+), 4 deletions(-)

Comments

Mario Limonciello Nov. 14, 2022, 10:29 p.m. UTC | #1 
Please run this through a spell checker before v5.

On 11/10/2022 11:58, Perry Yuan wrote:
> Introduce ``amd-pstate`` CPPC has two operation modes:
> * CPPC Autonomous (active) mode
> * CPPC non-autonomous (passive) mode.
> active mode and passive mode can be choosed by whith different kernel parameters.

can be chosen by different kernel parameters

> 
> Signed-off-by: Perry Yuan <Perry.Yuan@amd.com>
> ---
>   Documentation/admin-guide/pm/amd-pstate.rst | 47 +++++++++++++++++++--
>   1 file changed, 43 insertions(+), 4 deletions(-)
> 
> diff --git a/Documentation/admin-guide/pm/amd-pstate.rst b/Documentation/admin-guide/pm/amd-pstate.rst
> index e7488891b12f..6ba02a658b31 100644
> --- a/Documentation/admin-guide/pm/amd-pstate.rst
> +++ b/Documentation/admin-guide/pm/amd-pstate.rst
> @@ -302,11 +302,11 @@ efficiency frequency management method on AMD processors.
>   Kernel Module Options for ``amd-pstate``
>   =========================================
>   
> -.. _shared_mem:
> +.. legacy_cppc:
>   
> -``shared_mem``
> -Use a module param (shared_mem) to enable related processors manually with
> -**amd_pstate.shared_mem=1**.
> +``legacy_cppc``
> +Use a module param (legacy_cppc) to enable related processors manually with
> +**amd_pstate=legacy_cppc**.
>   Due to the performance issue on the processors with `Shared Memory Support
>   <perf_cap_>`_, we disable it presently and will re-enable this by default
>   once we address performance issue with this solution.
> @@ -321,6 +321,45 @@ If the CPU flags have ``cppc``, then this processor supports `Full MSR Support
>   <perf_cap_>`_. Otherwise, it supports `Shared Memory Support <perf_cap_>`_.
>   
>   
> +AMD Pstae Driver Operation Modes

Pstate

> +=================================
> +
> +``amd-pstate`` CPPC has two operation modes: CPPC Autonomous(active) mode and
> +CPPC non-autonomous(passive) mode.
> +active mode and passive mode can be choosed by whith different kernel parameters.

can be chosen by different kernel parameters

> +When in Autonomous mode, CPPC ignores requests done in the Desired Performance
> +Target register and takes into account only the values set to the Minimum requested
> +performance, Maximum requested performance, and Energy Performance Preference
> +registers. When Autonomous is disabled, it only considers the Desired Performance Target.
> +
> +Active Mode
> +------------
> +
> +``amd-pstate-epp``
> +
> +This is the low-level firmware control mode which is implemented by ``amd-pstate-epp``
> +driver with ``amd-pstate=active`` passed to the kernel in the command line.
> +In this mode, ``amd-pstate-epp`` driver provides a hint to the hardware if software
> +wants to bias toward performance (0x0) or energy efficiency (0xff) to the CPPC firmware.
> +then CPPC power algorithm will calculate the runtime workload and adjust the realtime
> +cores frequency according to the power supply and thermal, core voltage and some other
> +hardware conditions.
> +
> +Passive Mode
> +------------
> +
> +``amd-pstate``
> +
> +It will be enabled if the ``amd_pstate=passive`` is passed to the kernel in the command line.
> +In this mode, ``amd-pstate``driver software specifies a desired QoS target in the CPPC
> +performance scale as a relative number. This can be expressed as percentage of nominal
> +performance (infrastructure max). Below the nominal sustained performance level,
> +desired performance expresses the average performance level of the processor subject
> +to the Performance Reduction Tolerance register. Above the nominal performance level,
> +processor must provide at least nominal performance requested and go higher if current
> +operating conditions allow.
> +
> +
>   ``cpupower`` tool support for ``amd-pstate``
>   ===============================================
>
Yuan, Perry Dec. 2, 2022, 8:20 a.m. UTC | #2 
[AMD Official Use Only - General]

Hi Mario 

> -----Original Message-----
> From: Limonciello, Mario <Mario.Limonciello@amd.com>
> Sent: Tuesday, November 15, 2022 6:29 AM
> To: Yuan, Perry <Perry.Yuan@amd.com>; rafael.j.wysocki@intel.com; Huang,
> Ray <Ray.Huang@amd.com>; viresh.kumar@linaro.org
> Cc: Sharma, Deepak <Deepak.Sharma@amd.com>; Fontenot, Nathan
> <Nathan.Fontenot@amd.com>; Deucher, Alexander
> <Alexander.Deucher@amd.com>; Huang, Shimmer
> <Shimmer.Huang@amd.com>; Du, Xiaojian <Xiaojian.Du@amd.com>; Meng,
> Li (Jassmine) <Li.Meng@amd.com>; Karny, Wyes <Wyes.Karny@amd.com>;
> linux-pm@vger.kernel.org; linux-kernel@vger.kernel.org
> Subject: Re: [PATCH v4 9/9] Documentation: amd-pstate: add amd pstate
> driver mode introduction
> 
> Please run this through a spell checker before v5.
> 
> On 11/10/2022 11:58, Perry Yuan wrote:
> > Introduce ``amd-pstate`` CPPC has two operation modes:
> > * CPPC Autonomous (active) mode
> > * CPPC non-autonomous (passive) mode.
> > active mode and passive mode can be choosed by whith different kernel
> parameters.
> 
> can be chosen by different kernel parameters

Forget to reply this, 
I have fixed the words typo in the  v6.
Thanks for your review. 
Perry. 

> 
> >
> > Signed-off-by: Perry Yuan <Perry.Yuan@amd.com>
> > ---
> >   Documentation/admin-guide/pm/amd-pstate.rst | 47
> +++++++++++++++++++--
> >   1 file changed, 43 insertions(+), 4 deletions(-)
> >
> > diff --git a/Documentation/admin-guide/pm/amd-pstate.rst
> > b/Documentation/admin-guide/pm/amd-pstate.rst
> > index e7488891b12f..6ba02a658b31 100644
> > --- a/Documentation/admin-guide/pm/amd-pstate.rst
> > +++ b/Documentation/admin-guide/pm/amd-pstate.rst
> > @@ -302,11 +302,11 @@ efficiency frequency management method on
> AMD processors.
> >   Kernel Module Options for ``amd-pstate``
> >   =========================================
> >
> > -.. _shared_mem:
> > +.. legacy_cppc:
> >
> > -``shared_mem``
> > -Use a module param (shared_mem) to enable related processors
> manually
> > with -**amd_pstate.shared_mem=1**.
> > +``legacy_cppc``
> > +Use a module param (legacy_cppc) to enable related processors
> > +manually with **amd_pstate=legacy_cppc**.
> >   Due to the performance issue on the processors with `Shared Memory
> Support
> >   <perf_cap_>`_, we disable it presently and will re-enable this by default
> >   once we address performance issue with this solution.
> > @@ -321,6 +321,45 @@ If the CPU flags have ``cppc``, then this processor
> supports `Full MSR Support
> >   <perf_cap_>`_. Otherwise, it supports `Shared Memory Support
> <perf_cap_>`_.
> >
> >
> > +AMD Pstae Driver Operation Modes
> 
> Pstate
> 
> > +=================================
> > +
> > +``amd-pstate`` CPPC has two operation modes: CPPC Autonomous(active)
> > +mode and CPPC non-autonomous(passive) mode.
> > +active mode and passive mode can be choosed by whith different kernel
> parameters.
> 
> can be chosen by different kernel parameters
> 
> > +When in Autonomous mode, CPPC ignores requests done in the Desired
> > +Performance Target register and takes into account only the values
> > +set to the Minimum requested performance, Maximum requested
> > +performance, and Energy Performance Preference registers. When
> Autonomous is disabled, it only considers the Desired Performance Target.
> > +
> > +Active Mode
> > +------------
> > +
> > +``amd-pstate-epp``
> > +
> > +This is the low-level firmware control mode which is implemented by
> > +``amd-pstate-epp`` driver with ``amd-pstate=active`` passed to the kernel
> in the command line.
> > +In this mode, ``amd-pstate-epp`` driver provides a hint to the
> > +hardware if software wants to bias toward performance (0x0) or energy
> efficiency (0xff) to the CPPC firmware.
> > +then CPPC power algorithm will calculate the runtime workload and
> > +adjust the realtime cores frequency according to the power supply and
> > +thermal, core voltage and some other hardware conditions.
> > +
> > +Passive Mode
> > +------------
> > +
> > +``amd-pstate``
> > +
> > +It will be enabled if the ``amd_pstate=passive`` is passed to the kernel in
> the command line.
> > +In this mode, ``amd-pstate``driver software specifies a desired QoS
> > +target in the CPPC performance scale as a relative number. This can
> > +be expressed as percentage of nominal performance (infrastructure
> > +max). Below the nominal sustained performance level, desired
> > +performance expresses the average performance level of the processor
> > +subject to the Performance Reduction Tolerance register. Above the
> > +nominal performance level, processor must provide at least nominal
> performance requested and go higher if current operating conditions allow.
> > +
> > +
> >   ``cpupower`` tool support for ``amd-pstate``
> >   ===============================================
> >
diff mbox series

Patch

diff --git a/Documentation/admin-guide/pm/amd-pstate.rst b/Documentation/admin-guide/pm/amd-pstate.rst
index e7488891b12f..6ba02a658b31 100644
--- a/Documentation/admin-guide/pm/amd-pstate.rst
+++ b/Documentation/admin-guide/pm/amd-pstate.rst
@@ -302,11 +302,11 @@  efficiency frequency management method on AMD processors.
 Kernel Module Options for ``amd-pstate``
 =========================================
 
-.. _shared_mem:
+.. legacy_cppc:
 
-``shared_mem``
-Use a module param (shared_mem) to enable related processors manually with
-**amd_pstate.shared_mem=1**.
+``legacy_cppc``
+Use a module param (legacy_cppc) to enable related processors manually with
+**amd_pstate=legacy_cppc**.
 Due to the performance issue on the processors with `Shared Memory Support
 <perf_cap_>`_, we disable it presently and will re-enable this by default
 once we address performance issue with this solution.
@@ -321,6 +321,45 @@  If the CPU flags have ``cppc``, then this processor supports `Full MSR Support
 <perf_cap_>`_. Otherwise, it supports `Shared Memory Support <perf_cap_>`_.
 
 
+AMD Pstae Driver Operation Modes
+=================================
+
+``amd-pstate`` CPPC has two operation modes: CPPC Autonomous(active) mode and
+CPPC non-autonomous(passive) mode.
+active mode and passive mode can be choosed by whith different kernel parameters.
+When in Autonomous mode, CPPC ignores requests done in the Desired Performance 
+Target register and takes into account only the values set to the Minimum requested
+performance, Maximum requested performance, and Energy Performance Preference
+registers. When Autonomous is disabled, it only considers the Desired Performance Target.
+
+Active Mode
+------------
+
+``amd-pstate-epp``
+
+This is the low-level firmware control mode which is implemented by ``amd-pstate-epp``
+driver with ``amd-pstate=active`` passed to the kernel in the command line.
+In this mode, ``amd-pstate-epp`` driver provides a hint to the hardware if software
+wants to bias toward performance (0x0) or energy efficiency (0xff) to the CPPC firmware.
+then CPPC power algorithm will calculate the runtime workload and adjust the realtime
+cores frequency according to the power supply and thermal, core voltage and some other
+hardware conditions.
+
+Passive Mode
+------------
+
+``amd-pstate``
+
+It will be enabled if the ``amd_pstate=passive`` is passed to the kernel in the command line.
+In this mode, ``amd-pstate``driver software specifies a desired QoS target in the CPPC
+performance scale as a relative number. This can be expressed as percentage of nominal
+performance (infrastructure max). Below the nominal sustained performance level,
+desired performance expresses the average performance level of the processor subject
+to the Performance Reduction Tolerance register. Above the nominal performance level,
+processor must provide at least nominal performance requested and go higher if current
+operating conditions allow.
+
+
 ``cpupower`` tool support for ``amd-pstate``
 ===============================================