RE: [PATCH] igb: adjust ptp timestamps for tx/rx latency

[Brown, Aaron F]

> From: netdev-owner@xxxxxxxxxxxxxxx [mailto:netdev-
> owner@xxxxxxxxxxxxxxx] On Behalf Of Nathan Sullivan
> Sent: Tuesday, May 3, 2016 4:11 PM
> To: Kirsher, Jeffrey T <jeffrey.t.kirsher@xxxxxxxxx>; Brandeburg, Jesse
> <jesse.brandeburg@xxxxxxxxx>; Nelson, Shannon
> <shannon.nelson@xxxxxxxxx>; Wyborny, Carolyn
> <carolyn.wyborny@xxxxxxxxx>; Skidmore, Donald C
> <donald.c.skidmore@xxxxxxxxx>; Allan, Bruce W <bruce.w.allan@xxxxxxxxx>;
> Ronciak, John <john.ronciak@xxxxxxxxx>; Williams, Mitch A
> <mitch.a.williams@xxxxxxxxx>
> Cc: intel-wired-lan@xxxxxxxxxxxxxxxx; netdev@xxxxxxxxxxxxxxx; linux-
> kernel@xxxxxxxxxxxxxxx; Nathan Sullivan <nathan.sullivan@xxxxxx>
> Subject: [PATCH] igb: adjust ptp timestamps for tx/rx latency
> 
> Table 7-62 on page 338 of the i210 datasheet lists TX and RX latencies
> for the various speeds the chip supports.  To give better ptp timestamp
> accuracy, adjust the timestamps by the amounts Intel gives based on
> current link speed.
> 
> Signed-off-by: Nathan Sullivan <nathan.sullivan@xxxxxx>
> ---
>  drivers/net/ethernet/intel/igb/igb.h     |    8 +++++++
>  drivers/net/ethernet/intel/igb/igb_ptp.c |   36
> ++++++++++++++++++++++++++++++
>  2 files changed, 44 insertions(+)

Tested-by: Aaron Brown <aaron.f.brown@xxxxxxxxx>