[Linuxptp-users] Non-zero correction field with linuxptp

[Harini K. <har...@gm...>]

Hi,

Could you please help us out on a query regarding the use of non-zero
correction field in PTP event frames?
We are working on a 1588 solution with a setup involving transparent clock.
The setup is essentially as follows:

1588_Master <===> E2E_TC <===> 1588_Slave

We are running linuxptp on both master and slave. The master and slave are
either PCs with Ubuntu OS or a Xilinx embedded system with linux. The transit
time is getting added in the TC i.e. it updates the 8 byte correction field.
Does linuxptp consider this field in delay computations? What config needs to be
enabled for the same? When we tried this by updating the correction field
(even if only with 1 ns), we observed a hang - there was no DelayResponse frame
observed and the sync stopped in s2 stage. If the correction field is made
zero again (dynamically in the TC), the sync resumes as expected.

We have looked up other queries on delay correction on the mailing list but
they were mostly static delays that can be handled in the kernel driver.
This is specifically regarding the correction field
(offset 8 bytes from PTPHDR, size 8 bytes) .
Please suggest how to proceed.

Regards,
Harini