Re: [Linuxptp-users] Hardware PTP clock synchronization

[Keller, J. E <jac...@in...>]

On Mon, 2013-08-05 at 10:30 +0300, Гаврилов Александр wrote:
> Hello!
> 
> And more thing:
> on my card 82676 i can read time registers directly in DOS - it work
> fine. But in linux this causes an error "tx timestamp timeout".
> 
> Sincerely, Alexander.

How are you doing this? Some other program running along side? or just
using a register read tool like ethregs, ethtool, or your own custom
one?

You should not interfere with registers of a device while it is in
operation. Especially not the 1588 registers. The Tx time stamp
registers read-once to unlatch. After they are read, the flag which
indicates that there is a time stamp available for the driver is cleared
and the hardware is free to take a new time stamp. Effectively you
trying to read directly from the registers interferes with how the
driver has to behave to function correctly!!!

Please explain what you are trying to do and why. Maybe we can find a
better way to do what you want.

I am almost certain this is why you are having a problem....

Thanks,
Jake