Le Tue, 19 Aug 2025 09:12:54 +0200,
Oleksij Rempel [off-list ref] a écrit :

Extend ETHTOOL_MSG_LINKSTATE_GET to optionally return a simplified
Mean Square Error (MSE) reading alongside existing link status fields.

The new attributes are:
  - ETHTOOL_A_LINKSTATE_MSE_VALUE: current average MSE value
  - ETHTOOL_A_LINKSTATE_MSE_MAX: scale limit for the reported value
  - ETHTOOL_A_LINKSTATE_MSE_CHANNEL: source channel selector

This path reuses the PHY MSE core API, but only retrieves a single
value intended for quick link-health checks:
  * If the PHY supports a WORST channel selector, report its current
    average MSE.
  * Otherwise, if LINK-wide measurements are supported, report those.
  * If neither is available, omit the attributes.

Unlike the full MSE_GET interface, LINKSTATE_GET does not expose
per-channel or peak/worst-peak values and incurs minimal overhead.
Drivers that implement get_mse_config() / get_mse_snapshot() will
automatically populate this data.

The intent is to provide tooling with a “fast path” health indicator
without issuing a separate MSE_GET request, though the long-term
overlap with the full interface may need reevaluation.

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

Thank you!

-- 
Köry Maincent, Bootlin
Embedded Linux and kernel engineering
https://bootlin.com