Re: [PATCH net-next v6 07/16] net_tstamp: Add TIMESTAMPING SOFTWARE and HARDWARE mask

[Köry Maincent]

On Thu, 19 Oct 2023 10:48:04 -0400
Willem de Bruijn <willemdebruijn.kernel@xxxxxxxxx> wrote:

> On Thu, Oct 19, 2023 at 10:29 AM Kory Maincent
> <kory.maincent@xxxxxxxxxxx> wrote:
> >
> > Timestamping software or hardware flags are often used as a group,
> > therefore adding these masks will easier future use.  
> 
> This assumes that device support for timestamping is often symmetric:
> a device supports both rx and tx, or neither.
>
> All devices support software receive timestamping, as that timestamp
> is taken in the core network stack. But to support transmit timestamps
> drivers have to call sbk_tstamp_tx in their ndo_start_xmit.

Yes, and in that software only case they often call ethtool_op_get_ts_info to
fill the timestamp info.

There is several drivers that support hardware and software timestamp, these
mask could be useful for these. In case of asymmetric support we can still use
the SOF_TIMESTAMPING_RX/TX_SOFTWARE flags.

I forgot to specify, in the commit message but this patch is mainly to ease
the next patch of this series to deal with software/hardware time stamping.
Maybe you prefer to have this squash into next patch as had suggested Florian
in last version.

Köry