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[net-next,v3,5/7] net: ethtool: Add new power limit get and set features

Message ID 20240614-feature_poe_power_cap-v3-5-a26784e78311@bootlin.com (mailing list archive)
State Changes Requested
Delegated to: Netdev Maintainers
Headers show
Series net: pse-pd: Add new PSE c33 features | expand

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Commit Message

Kory Maincent June 14, 2024, 2:33 p.m. UTC 
From: Kory Maincent (Dent Project) <kory.maincent@bootlin.com>

This patch expands the status information provided by ethtool for PSE c33
with power limit. It also adds a call to pse_ethtool_set_pw_limit() to
configure the PSE control power limit.

Signed-off-by: Kory Maincent <kory.maincent@bootlin.com>
---

Change in v3:
- Add ethtool netlink documentation.
---
 Documentation/networking/ethtool-netlink.rst |  8 ++++++
 include/uapi/linux/ethtool_netlink.h         |  1 +
 net/ethtool/pse-pd.c                         | 42 +++++++++++++++++++++++-----
 3 files changed, 44 insertions(+), 7 deletions(-)

Comments

Oleksij Rempel June 15, 2024, 3:59 p.m. UTC | #1 
Hi Köry,

On Fri, Jun 14, 2024 at 04:33:21PM +0200, Kory Maincent wrote:
> From: Kory Maincent (Dent Project) <kory.maincent@bootlin.com>
> 
> This patch expands the status information provided by ethtool for PSE c33
> with power limit. It also adds a call to pse_ethtool_set_pw_limit() to
> configure the PSE control power limit.
> 
> Signed-off-by: Kory Maincent <kory.maincent@bootlin.com>
> ---
> 
> Change in v3:
> - Add ethtool netlink documentation.
> ---
>  Documentation/networking/ethtool-netlink.rst |  8 ++++++
>  include/uapi/linux/ethtool_netlink.h         |  1 +
>  net/ethtool/pse-pd.c                         | 42 +++++++++++++++++++++++-----
>  3 files changed, 44 insertions(+), 7 deletions(-)
> 
> diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst
> index 7dbf2ef3ac0e..a78b6aea84af 100644
> --- a/Documentation/networking/ethtool-netlink.rst
> +++ b/Documentation/networking/ethtool-netlink.rst
> @@ -1737,6 +1737,7 @@ Kernel response contents:
>                                                    PoE PSE.
>    ``ETHTOOL_A_C33_PSE_EXT_SUBSTATE``         u32  power extended substatus of
>                                                    the PoE PSE.
> +  ``ETHTOOL_A_C33_PSE_PW_LIMIT``             u32  power limit of the PoE PSE.
>    ======================================  ======  =============================
>  
>  When set, the optional ``ETHTOOL_A_PODL_PSE_ADMIN_STATE`` attribute identifies
> @@ -1799,6 +1800,9 @@ Possible values are:
>  		  ethtool_c33_pse_ext_substate_power_not_available
>  		  ethtool_c33_pse_ext_substate_short_detected
>  
> +When set, the optional ``ETHTOOL_A_C33_PSE_PW_LIMIT`` attribute identifies
> +the C33 PSE power limit in mW.
> +
>  PSE_SET
>  =======
>  
> @@ -1810,6 +1814,7 @@ Request contents:
>    ``ETHTOOL_A_PSE_HEADER``                nested  request header
>    ``ETHTOOL_A_PODL_PSE_ADMIN_CONTROL``       u32  Control PoDL PSE Admin state
>    ``ETHTOOL_A_C33_PSE_ADMIN_CONTROL``        u32  Control PSE Admin state
> +  ``ETHTOOL_A_C33_PSE_PW_LIMIT``             u32  Control PoE PSE power limit
>    ======================================  ======  =============================
>  
>  When set, the optional ``ETHTOOL_A_PODL_PSE_ADMIN_CONTROL`` attribute is used
> @@ -1820,6 +1825,9 @@ to control PoDL PSE Admin functions. This option is implementing
>  The same goes for ``ETHTOOL_A_C33_PSE_ADMIN_CONTROL`` implementing
>  ``IEEE 802.3-2022`` 30.9.1.2.1 acPSEAdminControl.
>  
> +When set, the optional ``ETHTOOL_A_C33_PSE_PW_LIMIT`` attribute is used
> +to control C33 PSE power limit in mW.


The corresponding name int the IEEE 802.3-2022 seems to be pse_avail_pwr
in 145.2.5.4 Variables and pse_available_power in 33.2.4.4 Variables.

This variable is using classes instead of mW. pd692x0 seems to use
classes instead of mW too. May be it is better to use classes for UAPI
too? 

Regards,
Oleksij
Oleksij Rempel June 15, 2024, 6:28 p.m. UTC | #2 
On Sat, Jun 15, 2024 at 05:59:36PM +0200, Oleksij Rempel wrote:
> Hi Köry,
> 
> On Fri, Jun 14, 2024 at 04:33:21PM +0200, Kory Maincent wrote:
> > From: Kory Maincent (Dent Project) <kory.maincent@bootlin.com>
> > 
> > This patch expands the status information provided by ethtool for PSE c33
> > with power limit. It also adds a call to pse_ethtool_set_pw_limit() to
> > configure the PSE control power limit.
> > 
> > Signed-off-by: Kory Maincent <kory.maincent@bootlin.com>
> > ---
> > 
> > Change in v3:
> > - Add ethtool netlink documentation.
> > ---
> >  Documentation/networking/ethtool-netlink.rst |  8 ++++++
> >  include/uapi/linux/ethtool_netlink.h         |  1 +
> >  net/ethtool/pse-pd.c                         | 42 +++++++++++++++++++++++-----
> >  3 files changed, 44 insertions(+), 7 deletions(-)
> > 
> > diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst
> > index 7dbf2ef3ac0e..a78b6aea84af 100644
> > --- a/Documentation/networking/ethtool-netlink.rst
> > +++ b/Documentation/networking/ethtool-netlink.rst
> > @@ -1737,6 +1737,7 @@ Kernel response contents:
> >                                                    PoE PSE.
> >    ``ETHTOOL_A_C33_PSE_EXT_SUBSTATE``         u32  power extended substatus of
> >                                                    the PoE PSE.
> > +  ``ETHTOOL_A_C33_PSE_PW_LIMIT``             u32  power limit of the PoE PSE.
> >    ======================================  ======  =============================
> >  
> >  When set, the optional ``ETHTOOL_A_PODL_PSE_ADMIN_STATE`` attribute identifies
> > @@ -1799,6 +1800,9 @@ Possible values are:
> >  		  ethtool_c33_pse_ext_substate_power_not_available
> >  		  ethtool_c33_pse_ext_substate_short_detected
> >  
> > +When set, the optional ``ETHTOOL_A_C33_PSE_PW_LIMIT`` attribute identifies
> > +the C33 PSE power limit in mW.
> > +
> >  PSE_SET
> >  =======
> >  
> > @@ -1810,6 +1814,7 @@ Request contents:
> >    ``ETHTOOL_A_PSE_HEADER``                nested  request header
> >    ``ETHTOOL_A_PODL_PSE_ADMIN_CONTROL``       u32  Control PoDL PSE Admin state
> >    ``ETHTOOL_A_C33_PSE_ADMIN_CONTROL``        u32  Control PSE Admin state
> > +  ``ETHTOOL_A_C33_PSE_PW_LIMIT``             u32  Control PoE PSE power limit
> >    ======================================  ======  =============================
> >  
> >  When set, the optional ``ETHTOOL_A_PODL_PSE_ADMIN_CONTROL`` attribute is used
> > @@ -1820,6 +1825,9 @@ to control PoDL PSE Admin functions. This option is implementing
> >  The same goes for ``ETHTOOL_A_C33_PSE_ADMIN_CONTROL`` implementing
> >  ``IEEE 802.3-2022`` 30.9.1.2.1 acPSEAdminControl.
> >  
> > +When set, the optional ``ETHTOOL_A_C33_PSE_PW_LIMIT`` attribute is used
> > +to control C33 PSE power limit in mW.
> 
> 
> The corresponding name int the IEEE 802.3-2022 seems to be pse_avail_pwr
> in 145.2.5.4 Variables and pse_available_power in 33.2.4.4 Variables.
> 
> This variable is using classes instead of mW. pd692x0 seems to use
> classes instead of mW too. May be it is better to use classes for UAPI
> too? 

Huh... i took some more time to investigate it. Looks like there is no
simple answer. Some devices seems to write power class on the box. Other
client devices write power consumption in watts. IEEE 802.3-2022
provides LLDP specification with PowerValue for watts and PowerClass for
classes. Different product user interfaces provide class and/or watts.
So, let's go with watts then. Please update the name to something like
pse_available_power_value or pse_available_power_value_limit and
document how it is related to State diagrams in the IEEE spec.
Oleksij Rempel June 16, 2024, 6:07 a.m. UTC | #3 
On Sat, Jun 15, 2024 at 08:28:30PM +0200, Oleksij Rempel wrote:
> > > diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst
> > > index 7dbf2ef3ac0e..a78b6aea84af 100644
> > > --- a/Documentation/networking/ethtool-netlink.rst
> > > +++ b/Documentation/networking/ethtool-netlink.rst
> > > @@ -1737,6 +1737,7 @@ Kernel response contents:
> > >                                                    PoE PSE.
> > >    ``ETHTOOL_A_C33_PSE_EXT_SUBSTATE``         u32  power extended substatus of
> > >                                                    the PoE PSE.
> > > +  ``ETHTOOL_A_C33_PSE_PW_LIMIT``             u32  power limit of the PoE PSE.
> > >    ======================================  ======  =============================
> > >  
> > >  When set, the optional ``ETHTOOL_A_PODL_PSE_ADMIN_STATE`` attribute identifies
> > > @@ -1799,6 +1800,9 @@ Possible values are:
> > >  		  ethtool_c33_pse_ext_substate_power_not_available
> > >  		  ethtool_c33_pse_ext_substate_short_detected
> > >  
> > > +When set, the optional ``ETHTOOL_A_C33_PSE_PW_LIMIT`` attribute identifies
> > > +the C33 PSE power limit in mW.

Except of current value, we need an interface to return list of supported
ranges. For example a controller with flexible configuration will have
one entry 

Proposed interface may look like this:

  ``ETHTOOL_A_C33_PSE_AVAIL_PWR_VAL_LIMIT``  u32  Get PoE PSE currently configured power value limit
  ``ETHTOOL_A_C33_PSE_PWR_LIMIT_RANGES``     nested  Supported power limit configuration ranges  
  ======================================  ======  =============================

 +------------------------------------------+--------+----------------------------+
 | ``ETHTOOL_A_C33_PSE_PWR_VAL_LIMIT_RANGES``   | nested | array of power limit ranges|
 +-+----------------------------------------+--------+----------------------------+
 | | ``ETHTOOL_A_C33_PSE_PWR_VAL_LIMIT_RANGE_ENTRY`` | nested | one power limit range  |
 +-+-+--------------------------------------+--------+----------------------------+
 | | | ``ETHTOOL_A_C33_PSE_PWR_VAL_LIMIT_MIN``  | u32    | minimum power value (mW)   |
 +-+-+--------------------------------------+--------+----------------------------+
 | | | ``ETHTOOL_A_C33_PSE_PWR_VAL_LIMIT_MAX``  | u32    | maximum power value (mW)   |
 +-+-+--------------------------------------+--------+----------------------------+

The min/max values should provide ranges actually configurable by PSE controller.
If controller works with fixed classes, the min and max values will be equal.

The ethtool output may look like this:

$ ethtool --get-pse eth0

Power Information for eth0:
=====================================
Current Power Limit: 15000 mW
Current Power Consumption: 12000 mW

Supported Power Limit Ranges:
  - Range 1: 0 - 7500 mW
  - Range 2: 7501 - 15000 mW
  - Range 3: 15001 - 30000 mW

Port Power Priority: 3
Supported Priority Range: 1 - 5

Pairs in Use: 4
Pair Configuration Type: Alternative A (MDI-X) and Alternative B(S)
PSE Type: Type 4
Detected PD Class: Class 5 (40000 mW max)

Low-Level Classification:
  - Classification Type: Autodetected
  - Configured PD Class: Class 5 (40000 mW max)

Maintain Power Signature (MPS) State: Present


> > > +
> > >  PSE_SET
> > >  =======
> > >  
> > > @@ -1810,6 +1814,7 @@ Request contents:
> > >    ``ETHTOOL_A_PSE_HEADER``                nested  request header
> > >    ``ETHTOOL_A_PODL_PSE_ADMIN_CONTROL``       u32  Control PoDL PSE Admin state
> > >    ``ETHTOOL_A_C33_PSE_ADMIN_CONTROL``        u32  Control PSE Admin state
> > > +  ``ETHTOOL_A_C33_PSE_PW_LIMIT``             u32  Control PoE PSE power limit
> > >    ======================================  ======  =============================
> > >  
> > >  When set, the optional ``ETHTOOL_A_PODL_PSE_ADMIN_CONTROL`` attribute is used
> > > @@ -1820,6 +1825,9 @@ to control PoDL PSE Admin functions. This option is implementing
> > >  The same goes for ``ETHTOOL_A_C33_PSE_ADMIN_CONTROL`` implementing
> > >  ``IEEE 802.3-2022`` 30.9.1.2.1 acPSEAdminControl.
> > >  
> > > +When set, the optional ``ETHTOOL_A_C33_PSE_PW_LIMIT`` attribute is used
> > > +to control C33 PSE power limit in mW.
> > 
> > 
> > The corresponding name int the IEEE 802.3-2022 seems to be pse_avail_pwr
> > in 145.2.5.4 Variables and pse_available_power in 33.2.4.4 Variables.
> > 
> > This variable is using classes instead of mW. pd692x0 seems to use
> > classes instead of mW too. May be it is better to use classes for UAPI
> > too? 
> 
> Huh... i took some more time to investigate it. Looks like there is no
> simple answer. Some devices seems to write power class on the box. Other
> client devices write power consumption in watts. IEEE 802.3-2022
> provides LLDP specification with PowerValue for watts and PowerClass for
> classes. Different product user interfaces provide class and/or watts.
> So, let's go with watts then. Please update the name to something like
> pse_available_power_value or pse_available_power_value_limit and
> document how it is related to State diagrams in the IEEE spec.

Here is proposal for documentation:

  ``ETHTOOL_A_C33_PSE_AVAIL_PWR_VAL_LIMIT``  u32  Control PoE PSE available power value limit

When set, the optional ``ETHTOOL_A_C33_PSE_AVAIL_PWR_VAL_LIMIT`` attribute is
used  to control the available power value limit for C33 PSE in milliwatts.
This attribute corresponds  to the `pse_available_power` variable described in
``IEEE 802.3-2022`` 33.2.4.4 Variables  and `pse_avail_pwr` in 145.2.5.4
Variables, which are described in power classes. 

It was decided to use milliwatts for this interface to unify it with other
power monitoring interfaces, which also use milliwatts, and to align with
various existing products that document power consumption in watts rather than
classes. If power limit configuration based on classes is needed, the
conversion can be done in user space, for example by ethtool.
Kory Maincent June 17, 2024, 4:14 p.m. UTC | #4 
On Sun, 16 Jun 2024 08:07:20 +0200
Oleksij Rempel <o.rempel@pengutronix.de> wrote:

> On Sat, Jun 15, 2024 at 08:28:30PM +0200, Oleksij Rempel wrote:
>  [...]  
> 
> Except of current value, we need an interface to return list of supported
> ranges. For example a controller with flexible configuration will have
> one entry 

Yes, good idea.
 
> Proposed interface may look like this:
> 
>   ``ETHTOOL_A_C33_PSE_AVAIL_PWR_VAL_LIMIT``  u32  Get PoE PSE currently
> configured power value limit ``ETHTOOL_A_C33_PSE_PWR_LIMIT_RANGES``
> nested  Supported power limit configuration ranges
> ======================================  ======  =============================
> 
>  +------------------------------------------+--------+----------------------------+
>  | ``ETHTOOL_A_C33_PSE_PWR_VAL_LIMIT_RANGES``   | nested | array of power
> limit ranges|
> +-+----------------------------------------+--------+----------------------------+
> | | ``ETHTOOL_A_C33_PSE_PWR_VAL_LIMIT_RANGE_ENTRY`` | nested | one power
> limit range  |
> +-+-+--------------------------------------+--------+----------------------------+
> | | | ``ETHTOOL_A_C33_PSE_PWR_VAL_LIMIT_MIN``  | u32    | minimum power value
> (mW)   |
> +-+-+--------------------------------------+--------+----------------------------+
> | | | ``ETHTOOL_A_C33_PSE_PWR_VAL_LIMIT_MAX``  | u32    | maximum power value
> (mW)   |
> +-+-+--------------------------------------+--------+----------------------------+

Not sure the ETHTOOL_A_C33_PSE_PWR_VAL_LIMIT_RANGE_ENTRY bring anything
interesting.

 +--------------------------------------------+--------+----------------------------+
 | ``ETHTOOL_A_C33_PSE_PWR_VAL_LIMIT_RANGES`` | nested | array of power limit ranges|
 +-+------------------------------------------+--------+----------------------------+
 | | ``ETHTOOL_A_C33_PSE_PWR_VAL_LIMIT_MIN``  | u32    | minimum power value (mW)   |
 +-+------------------------------------------+--------+----------------------------+
 | | ``ETHTOOL_A_C33_PSE_PWR_VAL_LIMIT_MAX``  | u32    | maximum power value (mW)   |
 +-+------------------------------------------+--------+----------------------------+

> > Huh... i took some more time to investigate it. Looks like there is no
> > simple answer. Some devices seems to write power class on the box. Other
> > client devices write power consumption in watts. IEEE 802.3-2022
> > provides LLDP specification with PowerValue for watts and PowerClass for
> > classes. Different product user interfaces provide class and/or watts.
> > So, let's go with watts then. Please update the name to something like
> > pse_available_power_value or pse_available_power_value_limit and
> > document how it is related to State diagrams in the IEEE spec.  
> 
> Here is proposal for documentation:
> 
>   ``ETHTOOL_A_C33_PSE_AVAIL_PWR_VAL_LIMIT``  u32  Control PoE PSE available
> power value limit
> 
> When set, the optional ``ETHTOOL_A_C33_PSE_AVAIL_PWR_VAL_LIMIT`` attribute is
> used  to control the available power value limit for C33 PSE in milliwatts.
> This attribute corresponds  to the `pse_available_power` variable described in
> ``IEEE 802.3-2022`` 33.2.4.4 Variables  and `pse_avail_pwr` in 145.2.5.4
> Variables, which are described in power classes. 
> 
> It was decided to use milliwatts for this interface to unify it with other
> power monitoring interfaces, which also use milliwatts, and to align with
> various existing products that document power consumption in watts rather than
> classes. If power limit configuration based on classes is needed, the
> conversion can be done in user space, for example by ethtool.

Thanks for the rephrasing!

Regards,
Oleksij Rempel June 17, 2024, 7:57 p.m. UTC | #5 
On Mon, Jun 17, 2024 at 06:14:13PM +0200, Kory Maincent wrote:
> >  +------------------------------------------+--------+----------------------------+
> >  | ``ETHTOOL_A_C33_PSE_PWR_VAL_LIMIT_RANGES``   | nested | array of power
> > limit ranges|
> > +-+----------------------------------------+--------+----------------------------+
> > | | ``ETHTOOL_A_C33_PSE_PWR_VAL_LIMIT_RANGE_ENTRY`` | nested | one power
> > limit range  |
> > +-+-+--------------------------------------+--------+----------------------------+
> > | | | ``ETHTOOL_A_C33_PSE_PWR_VAL_LIMIT_MIN``  | u32    | minimum power value
> > (mW)   |
> > +-+-+--------------------------------------+--------+----------------------------+
> > | | | ``ETHTOOL_A_C33_PSE_PWR_VAL_LIMIT_MAX``  | u32    | maximum power value
> > (mW)   |
> > +-+-+--------------------------------------+--------+----------------------------+
> 
> Not sure the ETHTOOL_A_C33_PSE_PWR_VAL_LIMIT_RANGE_ENTRY bring anything
> interesting.
> 
>  +--------------------------------------------+--------+----------------------------+
>  | ``ETHTOOL_A_C33_PSE_PWR_VAL_LIMIT_RANGES`` | nested | array of power limit ranges|
>  +-+------------------------------------------+--------+----------------------------+
>  | | ``ETHTOOL_A_C33_PSE_PWR_VAL_LIMIT_MIN``  | u32    | minimum power value (mW)   |
>  +-+------------------------------------------+--------+----------------------------+
>  | | ``ETHTOOL_A_C33_PSE_PWR_VAL_LIMIT_MAX``  | u32    | maximum power value (mW)   |
>  +-+------------------------------------------+--------+----------------------------+

Ack. Good point.
diff mbox series

Patch

diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst
index 7dbf2ef3ac0e..a78b6aea84af 100644
--- a/Documentation/networking/ethtool-netlink.rst
+++ b/Documentation/networking/ethtool-netlink.rst
@@ -1737,6 +1737,7 @@  Kernel response contents:
                                                   PoE PSE.
   ``ETHTOOL_A_C33_PSE_EXT_SUBSTATE``         u32  power extended substatus of
                                                   the PoE PSE.
+  ``ETHTOOL_A_C33_PSE_PW_LIMIT``             u32  power limit of the PoE PSE.
   ======================================  ======  =============================
 
 When set, the optional ``ETHTOOL_A_PODL_PSE_ADMIN_STATE`` attribute identifies
@@ -1799,6 +1800,9 @@  Possible values are:
 		  ethtool_c33_pse_ext_substate_power_not_available
 		  ethtool_c33_pse_ext_substate_short_detected
 
+When set, the optional ``ETHTOOL_A_C33_PSE_PW_LIMIT`` attribute identifies
+the C33 PSE power limit in mW.
+
 PSE_SET
 =======
 
@@ -1810,6 +1814,7 @@  Request contents:
   ``ETHTOOL_A_PSE_HEADER``                nested  request header
   ``ETHTOOL_A_PODL_PSE_ADMIN_CONTROL``       u32  Control PoDL PSE Admin state
   ``ETHTOOL_A_C33_PSE_ADMIN_CONTROL``        u32  Control PSE Admin state
+  ``ETHTOOL_A_C33_PSE_PW_LIMIT``             u32  Control PoE PSE power limit
   ======================================  ======  =============================
 
 When set, the optional ``ETHTOOL_A_PODL_PSE_ADMIN_CONTROL`` attribute is used
@@ -1820,6 +1825,9 @@  to control PoDL PSE Admin functions. This option is implementing
 The same goes for ``ETHTOOL_A_C33_PSE_ADMIN_CONTROL`` implementing
 ``IEEE 802.3-2022`` 30.9.1.2.1 acPSEAdminControl.
 
+When set, the optional ``ETHTOOL_A_C33_PSE_PW_LIMIT`` attribute is used
+to control C33 PSE power limit in mW.
+
 RSS_GET
 =======
 
diff --git a/include/uapi/linux/ethtool_netlink.h b/include/uapi/linux/ethtool_netlink.h
index 398a0aa8daad..62ac9e1001bf 100644
--- a/include/uapi/linux/ethtool_netlink.h
+++ b/include/uapi/linux/ethtool_netlink.h
@@ -919,6 +919,7 @@  enum {
 	ETHTOOL_A_C33_PSE_ACTUAL_PW,		/* u32 */
 	ETHTOOL_A_C33_PSE_EXT_STATE,		/* u32 */
 	ETHTOOL_A_C33_PSE_EXT_SUBSTATE,		/* u32 */
+	ETHTOOL_A_C33_PSE_PW_LIMIT,		/* u32 */
 
 	/* add new constants above here */
 	__ETHTOOL_A_PSE_CNT,
diff --git a/net/ethtool/pse-pd.c b/net/ethtool/pse-pd.c
index fec56db557d3..5c5eccd5b32b 100644
--- a/net/ethtool/pse-pd.c
+++ b/net/ethtool/pse-pd.c
@@ -94,6 +94,9 @@  static int pse_reply_size(const struct ethnl_req_info *req_base,
 		len += nla_total_size(sizeof(u32)); /* _C33_PSE_EXT_STATE */
 	if (st->c33_ext_state_info.__c33_pse_ext_substate > 0)
 		len += nla_total_size(sizeof(u32)); /* _C33_PSE_EXT_SUBSTATE */
+	if (st->c33_pw_limit > 0)
+		len += nla_total_size(sizeof(u32)); /* _C33_PSE_PW_LIMIT */
+
 	return len;
 }
 
@@ -144,6 +147,11 @@  static int pse_fill_reply(struct sk_buff *skb,
 			st->c33_ext_state_info.__c33_pse_ext_substate))
 		return -EMSGSIZE;
 
+	if (st->c33_pw_limit > 0 &&
+	    nla_put_u32(skb, ETHTOOL_A_C33_PSE_PW_LIMIT,
+			st->c33_pw_limit))
+		return -EMSGSIZE;
+
 	return 0;
 }
 
@@ -157,6 +165,7 @@  const struct nla_policy ethnl_pse_set_policy[ETHTOOL_A_PSE_MAX + 1] = {
 	[ETHTOOL_A_C33_PSE_ADMIN_CONTROL] =
 		NLA_POLICY_RANGE(NLA_U32, ETHTOOL_C33_PSE_ADMIN_STATE_DISABLED,
 				 ETHTOOL_C33_PSE_ADMIN_STATE_ENABLED),
+	[ETHTOOL_A_C33_PSE_PW_LIMIT] = { .type = NLA_U32 },
 };
 
 static int
@@ -199,19 +208,38 @@  static int
 ethnl_set_pse(struct ethnl_req_info *req_info, struct genl_info *info)
 {
 	struct net_device *dev = req_info->dev;
-	struct pse_control_config config = {};
 	struct nlattr **tb = info->attrs;
 	struct phy_device *phydev;
+	int ret = 0;
 
 	phydev = dev->phydev;
+
+	if (tb[ETHTOOL_A_C33_PSE_PW_LIMIT]) {
+		unsigned int pw_limit = nla_get_u32(tb[ETHTOOL_A_C33_PSE_PW_LIMIT]);
+
+		ret = pse_ethtool_set_pw_limit(phydev->psec, info->extack,
+					       pw_limit);
+		if (ret)
+			return ret;
+	}
+
 	/* These values are already validated by the ethnl_pse_set_policy */
-	if (pse_has_podl(phydev->psec))
-		config.podl_admin_control = nla_get_u32(tb[ETHTOOL_A_PODL_PSE_ADMIN_CONTROL]);
-	if (pse_has_c33(phydev->psec))
-		config.c33_admin_control = nla_get_u32(tb[ETHTOOL_A_C33_PSE_ADMIN_CONTROL]);
+	if (tb[ETHTOOL_A_PODL_PSE_ADMIN_CONTROL] ||
+	    tb[ETHTOOL_A_C33_PSE_ADMIN_CONTROL]) {
+		struct pse_control_config config = {};
+
+		if (pse_has_podl(phydev->psec))
+			config.podl_admin_control = nla_get_u32(tb[ETHTOOL_A_PODL_PSE_ADMIN_CONTROL]);
+		if (pse_has_c33(phydev->psec))
+			config.c33_admin_control = nla_get_u32(tb[ETHTOOL_A_C33_PSE_ADMIN_CONTROL]);
+
+		ret = pse_ethtool_set_config(phydev->psec, info->extack,
+					     &config);
+		if (ret)
+			return ret;
+	}
 
-	/* Return errno directly - PSE has no notification */
-	return pse_ethtool_set_config(phydev->psec, info->extack, &config);
+	return ret;
 }
 
 const struct ethnl_request_ops ethnl_pse_request_ops = {