Re: [PATCH net-next v2 0/2] net: dsa: mv88e6xxx: various hwstamp fixes

[Luke Howard]

> ---
> Luke Howard (2):
>    net: dsa: mv88e6xxx: embedded PTP timestamp support

This can be improved: there is no need to extract the embedded timestamp in the PTP worker as it can be done directly in mv88e6xxx_port_rxtstamp() (provided tstamp_{cc,tc} are protected by a spinlock). DSA can deliver the frame normally, similar to ocelot_ptp_rx_timestamp().

Deferring to the worker can reorder frames such that PTP general messages arrive before the timestamped event messages, which confuses some other PTP implementations such as gptp2d [1].

This optimisation of course only works for ArrTSMode because there is no MDIO read required.

Luke

[1] https://github.com/xl4-shiro/excelfore-gptp