> On Jun 18, 2015, at 2:58 AM, Miroslav Lichvar <[email protected]> wrote: > >> On Thu, Jun 18, 2015 at 01:58:13AM +0000, Daniel Le wrote: >> Additionally, in slave clock operation and software time stamping mode, how >> (and where in the code) ptp4l can be forced to step the system clock with >> the time it first receives from a grandmaster clock? > > ptp4l should do that by default, it's set by the first_step_threshold > option.
Somehow when my system clock is initially (for example after a reboot) off the GM time by a couple of minutes, the master offset is huge and ptp4l takes hours to converge. Thanks. > >> I have a couple of questions about the frequency limit. How much may it be >> reasonably increased from the default of 200000000 (20%)? And this parameter >> is only configurable via the config file. Is that correct? > > Why do you need to increase it? 20% is a safe value for SW > timestamping. If you see clockcheck warning messages, it's probably a > bug in the kernel/driver. With HW timestamping a limit of a few > hundreds of ppm should be enough to cover the frequency offset between > a typical system clock and PTP clock. > > -- > Miroslav Lichvar ------------------------------------------------------------------------------ _______________________________________________ Linuxptp-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/linuxptp-users
