Hello,
I sampled a BeagleBoneBlack for use as a PTP client/end node. It has hardware timestamp capabilities on its ethernet jack and provided it has linux kernel support for it, the BBB is a capable PTP device. (I state this because not all ethernet jacks have this ability, looking at you RPI 3b/3b+/etc).
I was trying to figure out if the Beagle Board X-15 has hardware timestamp capabilities on its gigabit ethernet jacks. This would require a properly configured linux kernel (which i believe supports ieee1588 after in 4.x) I have not been able to figure that out from the wiki or support threads.
Best.
I don’t think so, I pulled the AM572x data sheet from TI and it doesn’t list IEE1588 like the BBB’s Sitara processor does.
It appears the X15 just has two “generic” gigabit Ethernet ports - no mention of VLANs either so seems bare bones.
-Ian
Thank you @iankwalker. I am unsure if being unlisted from the data sheet prevents the device from running ptp. I am no means a master of PTP or SOB/SOC devices, but I’ve struggled finding more devices than the beagle and some microchips that can run PTP. If someone has a x-15, could they give a readout of “ethtool -T eth0” & “ethtool -T eth1” (I’m assuming eth0 and eth1 correspond to the generic gigabit ports on the x-15, but they could have other names!). It would be beneficial if a readout of the kernel options for the following three parameters for the device could be made as well.
CONFIG_PPS=y (required)
PTP_1588_CLOCK=y (required)
CONFIG_NETWORK_PHY_TIMESTAMPING=y (optional - not used in BeageBone Black)
For reference, linuxptp system requires are the following (shamelessly borrowed from pps singal setup on beaglebone black pdf):
- Supported Ethernet MAC or PHY
a. The NIC of the BeageBone Black device is supported.
- Linux Kernel support for network packet timestamping (SO_TIMESTAMPING socket option) and clock control.
a. These features are part of the main line kernel since version 3.0.
- The linux kernel has to be compiled with the following configuration parameters:
Hi BobTheBuilder,
It seems likely to me that the X15 boards can only run a “software only” implementation of PTP. Software only implementations are not super accurate from my understanding of IEE1588 (Granted it’s been 10 years since I worked on implementing it for Ciena in some of their pizza box switches) . So that may or may not meet the time accuracy you need - You will have to decide that for your application.
To me, I see that the X15 doesn’t have native hardware support like the BBB does. This is what I was trying to explain previously. If you just need general protocol compatibility then the Linux software solution might be sufficient. If you need uS level timestamping ids doubtful you will get it from the X15.
-Ian
Thank you Ian! I appreciate the insight. I struggle around parts of this PTP; generally on which hardware can run it or not (w/ hardware timestamps, the RPI 3/3b+/4 has a ethernet jack that is really a usb iirc, and doesn’t allow for HW timestamping. Which threw me for a loop!) I loosely understand the kernel options/requirements. I struggle on the hardware end of it. I unfortunately do not have the ability to pickup an x15 and test it out currently (but would like to, or love if someone could confirm kernel options and show a ethtool -T output of the ethernet devices). I’d be interesting to see if it is possible to replace the jack with a more capable one, but that might be out of scope for what I am doing. I do own some BeagleBone Blacks and a Green, which are ptp capable and I’ve debated on using them for the projects in Bobsville and Fixham harbour; I was hoping for a solution that was a bit more powerful than the Beaglebone black, I noticed that the beaglebone AI uses a different and more powerful processor (similar processor to the x15 iirc?) but I could not find ptp support when skimming over the product details.
Maybe this is best for another thread, but is there a beaglebone black alternative/derivative with a gigabit jack? EDIT: Looking into the beaglebone enhanced by sanCloud.