Can the OPI5 be Configured to Run LCNC?

Yeah I think if the arch community would have been bigger I would like it more. It has some things that works better/faster than Debian but because not many software is made for Arch you'll need to compile a lot. The aur git does help but the things I needed were not configured right and that frustrated me indeed.

The missing dtb is because the kernel is directly from Rockchip which is missing that dtb
github.com/rockchip-linux/kernel/tree/de...64/boot/dts/rockchip

Armbian use their own fork which has the opi5 dtb in it. I could make a patch of course, there are some more things I would like to patch like the hdmi drivers which might make it possible to use panfork.

I didn't ask at the Armbian forum but saw that rodw had asked a few questions about it for another board and they weren't enthusiastic. There would need to be someone who wants to maintain it. It might not take long before the mainline kernel does work well enough, when that's ready it should be as simple as placing the preempt rt patch(es) in the right folder.

Actually, one of the developers took me under his wing and we moved off forum. Nobody knows about PREEMPT_RT and he is their real time guy who has specialized in Xenomai 4 and has not looked at PREEMPT_RT for a long time.
The build system has a lot of issues with their recent migration to their new build system, I went on holidays to Bali and we decided do give it a break for a while so he could get some of his work into mainline before resuming. I have some more pressing projects to complete right now.

The user build system is very powerful, and pretty well documented. If you are building a kernel now, you should be able to apply all your kernel config and patches in the userpatches folder for your architecture and kernel version. That is not created until you do an initial build. Use a custom config file to lock in your build parameters. I would try to use their EDGE branches and build Debian Bookworm because linuxcnc-uspace is in the Bookworm repos.

You don't need to build an image with a graphical environment as you can install that on the device from the repos. It adds a lot of time in the build system. Likewise once you can boot into Armbian (even non-rt will do), you can just build the kernel debs and copy them over and install with dpkg -i
You can check latency with cyclictest from the command line (sudo apt install rt-tests) and only install xfce and linuxcnc once you can see a reasonable result.

Hope that helps...

I'll have a look at it (hopefully) soon when the mainline kernel is ready for the rk3588(s). At the moment it isn't and the Rockchip kernel is a mess. I've been updating the gpu driver and some other things, that took me a day, it's selectively patched which I continued. Creating patches with the new build system doesn't seem to work yet, for that I use sometimes the old build system to do a lot of different files at different locations. 

For now the patches will add the dtb for the opi5 and update gpu/hdmi/usb drivers. I expect that Panfork will work with this kernel but need to test it first.
- Compiled kernel is with the WiFi drivers
- Config without (you could copy the config from the deb)
- I've placed the patches in the patch folder instead of userpatches because some patches has to be at the first place.

[url] mega.nz/folder/ypZxEAra#6NI9tibbdtoE_mAf8gdvKQ [/url]

So I reflashed the sd card with the ubuntu images I managed to compile instead of trying to reinstall the rt kernel. I did in fact do a apt upgrade which changed the kernel. I applied the hold and ran a few latency tests, one with youtube playing and one without with 6 glxgears running for at least 1000 seconds. It looks like the preempt rt patch is doing its job as you can see with the screenshots. I will also play around with the debian image as well. But I think I have enough to start playing with my Mesa 7196s board and see if I can't get a few stepper motors moving.

Great you've got it finally running, but there are some strange spikes on the ends I'm not sure what impact that will have, but they shouldn't be there. It could be the WiFi driver or power saving settings? Or did the temp rise too high?

You could try to see what causes the interrupts (probably on core 7).
cat /proc/interrupts. The updated drivers might help too.

could be temps, I live in Los Angeles and it got a little toasty this weekend. Currently the ambient temp in my Apt is 82F/27.8C. One of the things I wanted to machine is a nice beefy heat sink for the the OPi5 as there doesn't seem to be a commercial option as far as I know. The OPi5 had been running for at least an hour before I ran those tests so that could be a factor.

Also not excluding the other possibilities. I could hook up the Ethernet cable and run the test again to see if it is wifi.

As far as power savings I only disabled the suspend mode and screen dimming as well. I had forgotten to disable those and it ended up going into a power save mid test. Like you said it wouldn't wake up from it. So I had to start the test over after a forced shutdown. On that note I noticed it will not reboot upon a restart. It gets gets stuck at the boot process with a black screen. I have to power down and power back on in order for it to boot.

Also for some reason my last post didn't have the other image of the test without youtube playing in the background. Here is the one without a web browser open.