Balena OS 64 Bit does not work on Compute Module 3


We’re working on a Compute Module 3 based device and were possibly hoping to use Balena OS.

However I have it flashed on a compute module and notice our host board does not seem to be negotiating an ethernet connection where as Raspbian Does without issue.

I think even without connecting UART and starting to debug I’ve figured out the issue.

Would I be correct in thinking the kernel shipped with Balena OS is significantly cut down and missing many modules for drivers that most distributions have?

Thanks -

Ok I originally thought it was possibly Kernel related but now I’m suspecting 64 bit related.

The 32 Bit version (Armv7hf) works perfectly fine, both with the normal Raspberry Pi 3 variant and Fin (Cm3) variants so that made me wonder if the 64 bit kernel hadn’t been compiled for it.

However I went to try UART (after flashing the development version) and was getting nothing on the terminal and my 32 Bit version did.

Now I’ve looked at the boot partition I notice the 64 Bit release doesn’t have the device tree files for CM3.

So I believe the cause is actually no Compute Module support for the 64 Bit RPi 3 release?

Hi Ryan,

I’ve checked our images, and it looks like you’re correct. Our raspberrypi3-64 image doesn’t contain the correct device trees for the CM3. I’m not sure why this is, I’ll check into it and get back to you.

FYI @jakogut @Ryanteck I just did a couple PRs to fix this.

See comment at end of this GitHub issue…

We could spin a fincm3-64 as well, but I am not sure there is any need.

The other issue I can see is that the 64 Bit image hasn’t been updated since January, is this something that might improve?

Is it a custom CM3 based board you are testing with or it is commercially available board?

The currently published RPi 3 64bit release looks indeed old. There are very recent images available on our staging environment that you may check - It needs a separate free account. Please let us know about your findings.

It’s a custom CM3 based board that will soon be available. (Designed by me for Nebra LTD which @shawaj owns).

As I said on the second post however the missing devicetree files means it doesn’t work on any CM3 based board, including the official IO board and even the Fin.

I got it booting on the normal cloud service by adding in the device tree from Raspbian 64 Bit and it works fine.

It’s primarily just that it needs updating to include the latest device trees as standard.

Alright, I see ongoing work has already started for this, so once the right overlay is added for the RPi 3 64bit configuration things should start working out.

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Hi @Ryanteck

You recently enquired about an ETA for (this issue)[]. However, it needs to be fixed upstream before we can pull it in; the associated PR is here. So it is tricky to provide an ETA on this matter.

Kind regards

Ok thank you.

Just to let you know, this is progressing and should be sorted soon.

See this issue:

And this PR which just got merged in meta-raspberrypi:

@shawaj curious specifically about the possibility of a fincm3-64 image. We’d like to get mongo running on Balena fin. Will this update make that possible or will we need a separate fincm3 image?

Hello @alexanderkjones i don’t think the fin can run 64 bits OS (at the moment). Did you try to run mongoDB on 32 bits on your fleet?

Hi @mpous I had not looked at mongoDB 32bit as it sounds like it has been deprecated. Do you know if folks are using it in production?

Also, do you know if Fin will be able to run 64 bit with CM3 in the future or if the team is waiting for Finv2 with CM4?

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@alexanderkjones sorry for my delayed answer!

The main issue of not updating the fin to 64bit OS was due some camera/videocore driver issues on 64bits. Internally we created a discussion about running 64bit OS on the balenaFin.

Having said that, due the current limitations of the Compute Module supply chain, the Fin 2.0 have been delayed. You can read more here.