Re: [PATCH net-next v12 00/13] Add support for PSE budget evaluation strategy

[Oleksij Rempel <o.rempel@pengutronix.de>]

Hi Kory,

A short positive feedback: I partially tested this series and committed
patches for PSE support and impressed how easy it is now to configure
and use a switch with PoE support!

For testing I used "Novarq Tactical 1000" switch with Microchip EV14Y36A PSE
evaluation board attached to it.

I didn't had enough equipment for actual prioritization testing,
otherwise I would add my Tested-by here :)

Thank you!

On Sat, May 24, 2025 at 12:56:02PM +0200, Kory Maincent wrote:
> From: Kory Maincent (Dent Project) <kory.maincent@bootlin.com>
> 
> This series brings support for budget evaluation strategy in the PSE
> subsystem. PSE controllers can set priorities to decide which ports should
> be turned off in case of special events like over-current.
> 
> This patch series adds support for two budget evaluation strategy.
> 1. Static Method:
> 
>    This method involves distributing power based on PD classification.
>    It’s straightforward and stable, the PSE core keeping track of the
>    budget and subtracting the power requested by each PD’s class.
> 
>    Advantages: Every PD gets its promised power at any time, which
>    guarantees reliability.
> 
>    Disadvantages: PD classification steps are large, meaning devices
>    request much more power than they actually need. As a result, the power
>    supply may only operate at, say, 50% capacity, which is inefficient and
>    wastes money.
> 
> 2. Dynamic Method:
> 
>    To address the inefficiencies of the static method, vendors like
>    Microchip have introduced dynamic power budgeting, as seen in the
>    PD692x0 firmware. This method monitors the current consumption per port
>    and subtracts it from the available power budget. When the budget is
>    exceeded, lower-priority ports are shut down.
> 
>    Advantages: This method optimizes resource utilization, saving costs.
> 
>    Disadvantages: Low-priority devices may experience instability.
> 
> The UAPI allows adding support for software port priority mode managed from
> userspace later if needed.
> 
> Patches 1-2: Add support for interrupt event report in PSE core, ethtool
> 	     and ethtool specs.
> Patch 3: Adds support for interrupt and event report in TPS23881 driver.
> Patches 4,5: Add support for PSE power domain in PSE core and ethtool.
> Patches 6-8: Add support for budget evaluation strategy in PSE core,
> 	     ethtool and ethtool specs.
> Patches 9-11: Add support for port priority and power supplies in PD692x0
> 	      drivers.
> Patches 12,13: Add support for port priority in TPS23881 drivers.
> 
> Signed-off-by: Kory Maincent (Dent Project) <kory.maincent@bootlin.com>
> ---
> Changes in v12:
> - Rebase on net-next.
> - Link to v11: https://lore.kernel.org/r/20250520-feature_poe_port_prio-v11-0-bbaf447e1b28@bootlin.com
> 
> Changes in v11:
> - Move the PSE events enum description fully in the ethtool spec.
> - Remove the first patch which was useless as not used.
> - Split the second patch to separate the attached_phydev introduction to
>   the PSE interrupt support.
> - Link to v10: https://lore.kernel.org/r/20250506-feature_poe_port_prio-v10-0-55679a4895f9@bootlin.com
> 
> Changes in v10:
> - Change patch 2 and 7 due to possible used after free scenario or
>   deadlock scenario. Move the PSE notification send management to a
>   workqueue to protect it from the deadlock scenario.
> - Link to v9: https://lore.kernel.org/r/20250422-feature_poe_port_prio-v9-0-417fc007572d@bootlin.com
> 
> Changes in v9:
> - Add a missing check after skb creation.
> - Link to v8: https://lore.kernel.org/r/20250416-feature_poe_port_prio-v8-0-446c39dc3738@bootlin.com
> 
> Changes in v8:
> - Rename a few functions for better clarity.
> - Add missing kref_init in PSE power domain support and a wrong error
>   check condition.
> - Link to v7: https://lore.kernel.org/r/20250408-feature_poe_port_prio-v7-0-9f5fc9e329cd@bootlin.com
> 
> Changes in v7:
> - Add reference count and mutex lock for PSE power domain.
> - Add support to retry enabling port that failed to be powered in case of
>   port disconnection or priority change.
> - Use flags definition for pse events in ethtool specs.
> - Small changes in the TPS23881 driver.
> - Link to v6: https://lore.kernel.org/r/20250304-feature_poe_port_prio-v6-0-3dc0c5ebaf32@bootlin.com
> 
> Changes in v6:
> - Few typos.
> - Use uint instead of bitset for PSE_EVENT.
> - Remove report of budget evaluation strategy in the uAPI.
> - Link to v5: https://lore.kernel.org/r/20250218-feature_poe_port_prio-v5-0-3da486e5fd64@bootlin.com
> 
> Changes in v5:
> - Remove the first part of the patch series which tackled PSE
>   improvement and already gets merged:
>   https://lore.kernel.org/netdev/20250110-b4-feature_poe_arrange-v3-0-142279aedb94@bootlin.com/
> - Remove the PSE index support which is useless for now. The PSE power
>   domain ID is sufficient.
> - Add support for PD692x0 power supplies other than Vmain which was already
>   in the patch series.
> - Few other small fixes.
> - Link to v4: https://lore.kernel.org/r/20250103-feature_poe_port_prio-v4-0-dc91a3c0c187@bootlin.com
> 
> Changes in v4:
> - Remove disconnection policy.
> - Rename port priority mode to budget evaluation strategy.
> - Add cosmetic changes in PSE core.
> - Add support for port priority in PD692x0 driver.
> - Link to v3: https://lore.kernel.org/r/20241121-feature_poe_port_prio-v3-0-83299fa6967c@bootlin.com
> 
> Changes in v3:
> - Move power budget to regulator core.
> - Add disconnection policies with PIs using the same priority.
> - Several fixes on the TPS23881 drivers.
> - Several new cosmetic patches.
> - Link to v2: https://lore.kernel.org/r/20241030-feature_poe_port_prio-v2-0-9559622ee47a@bootlin.com
> 
> Changes in v2:
> - Rethink the port priority management.
> - Add PSE id.
> - Add support for PSE power domains.
> - Add get power budget regulator constraint.
> - Link to v1: https://lore.kernel.org/r/20241002-feature_poe_port_prio-v1-0-787054f74ed5@bootlin.com
> 
> ---
> Kory Maincent (13):
>       net: pse-pd: Introduce attached_phydev to pse control
>       net: pse-pd: Add support for reporting events
>       net: pse-pd: tps23881: Add support for PSE events and interrupts
>       net: pse-pd: Add support for PSE power domains
>       net: ethtool: Add support for new power domains index description
>       net: pse-pd: Add helper to report hardware enable status of the PI
>       net: pse-pd: Add support for budget evaluation strategies
>       net: ethtool: Add PSE port priority support feature
>       net: pse-pd: pd692x0: Add support for PSE PI priority feature
>       net: pse-pd: pd692x0: Add support for controller and manager power supplies
>       dt-bindings: net: pse-pd: microchip,pd692x0: Add manager regulator supply
>       net: pse-pd: tps23881: Add support for static port priority feature
>       dt-bindings: net: pse-pd: ti,tps23881: Add interrupt description
> 
>  .../bindings/net/pse-pd/microchip,pd692x0.yaml     |   22 +-
>  .../bindings/net/pse-pd/ti,tps23881.yaml           |    8 +
>  Documentation/netlink/specs/ethtool.yaml           |   76 ++
>  Documentation/networking/ethtool-netlink.rst       |   49 +
>  drivers/net/mdio/fwnode_mdio.c                     |   26 +-
>  drivers/net/pse-pd/pd692x0.c                       |  225 +++++
>  drivers/net/pse-pd/pse_core.c                      | 1068 +++++++++++++++++++-
>  drivers/net/pse-pd/tps23881.c                      |  403 +++++++-
>  include/linux/ethtool_netlink.h                    |    9 +
>  include/linux/pse-pd/pse.h                         |  108 +-
>  include/uapi/linux/ethtool_netlink_generated.h     |   40 +
>  net/ethtool/pse-pd.c                               |   63 ++
>  12 files changed, 2043 insertions(+), 54 deletions(-)
> ---
> base-commit: 573d51a171a9237a8ecd9921d9c69af74cc51ce8
> change-id: 20240913-feature_poe_port_prio-a51aed7332ec
> 
> Best regards,
> -- 
> Köry Maincent, Bootlin
> Embedded Linux and kernel engineering
> https://bootlin.com
> 
> 

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