[PATCH net-next 0/5] Flow control for NXP ENETC

[Jakub Kicinski]

On Sat, 17 Apr 2021 02:42:20 +0300 Vladimir Oltean wrote:
> From: Vladimir Oltean <vladimir.oltean at nxp.com>
> 
> This patch series contains logic for enabling the lossless mode on the
> RX rings of the ENETC, and the PAUSE thresholds on the internal FIFO
> memory.
> 
> During testing it was found that, with the default FIFO configuration,
> a sender which isn't persuaded by our PAUSE frames and keeps sending
> will cause some MAC RX frame errors. To mitigate this, we need to ensure
> that the FIFO never runs completely full, so we need to fix up a setting
> that was supposed to be configured well out of reset. Unfortunately this
> requires the addition of a new mini-driver.

FWIW back in the day when I was working on more advanced devices than 
I deal with these days I was expecting to eventually run into this as
well and create some form of devlink umbrella. IMHO such "mini driver"
is a natural place for a devlink instance, and not the PFs/ports.
Is this your thinking as well? AFAICT enetc doesn't implement devlink
today so you start from whatever model works best without worrying
about backward compat.