[dpdk-users] Intel X550 Receive timestamping for all packets

[Paul Emmerich]

Hi,

> terry.montague.1980 at btinternet.com:
> Hi all,
> Has anyone tried modifying the ixgbe PMD driver to allow an Intel X550 card to insert the extra 8 bytes of data at the end of each receive message, the 8 bytes containing the receive SYSTIME  timestamp ?

I've had that open as a todo for a year or so, and I've implemented it after seeing your email :)

> I've adjusted TYPE in TSYNCRXCTL to be "all packets" and set TSIP_UT_EN. I get the 8 bytes of data appended to all packets, but the controller doesn't populate the memory - the contents are left unchanged when transmitted.
> TS and TSIP are both set in the received RDESC descriptor (along with the receive byte count increasing by 8 bytes) so the adaptor is definitely doing something.

My implementation is here: https://github.com/libmoon/libmoon/commit/52f0b8cab580c8cf0579a03324cf0ac7f697e6e9#diff-0977b88594c9ac952093605f7aa091dcL109
Tested on an X550 and it works fine as far as I can tell from looking at a few histograms of inter-arrival times.


Paul