Support for Raspberry Pi 4


nope, that is not normal … it should quickly flash orange, then turn black and show a mouse pointer. if you see a blinking cursor mir did not start.


There may be other, earlier, errors but here Mir is failing to get access to the graphics DRM device. That explains why Mir doesn’t start.

You can get a longer listing with snap logs -n 100 mir-kiosk, but there is an incompatibility with kernel graphics module(s) in the image.

Have you tried ogra’s suggestion:


So I’ve done another clean Ubuntu Core install, did snap refresh and snap install --edge mir-kiosk and got the black screen with a blinking underscore cursor.
This time tho, here are the logs you’ve asked:

Changing the dtoverlay from dtoverlay=vc4-fkms-v3d to dtoverlay=vc4-kms-v3d makes Rpi4 unable to output any signal to the monitor. It’s black with my monitors no hdmi signal message.

Also snap command is not working for some reason after trying to install nano snap and rebooting.
$ snap logs -n 100 mir-kiosk
error: cannot communicate with server: Get http://localhost/v2/logs?n=100&names=mir-kiosk: dial unix /run/snapd.socket: connect: connection refused

The rest of the snap commands just hang and show empty line.


Got my 4GB pi4 last week, and it’s happily running raspbian.
I’m interested in accelerated opengl support in ubuntu core,
but haven’t gotten up the courage to try ogra’s build yet.


accelerated opengl isnt there yet on the Pi4 … but accelerated video playback works fine using the omxplayer-pi package as well as on the other pi’s (or on classic ubuntu) … only 1080p though, omxplayer upstream does not support h265 yet.


Looks like is a nice thread re gpu and rpi4 status…


Well, the thread you point to is about 64bit support (and indeed also mentions V3D on 64bit) … I dont plan to work on any 64bit images. The ones I built are for initial developer use until an official Ubuntu image exists.

Wether or not @ppisati plans to work on a 64bit kernel for upcoming official Ubuntu Pi4 images and when the Ubuntu kernels will be ready at all, I dont even know though.

Im a strong opponent of supporting arm64 on unsuited hardware.

64bit ARM means you allocate nearly twice the ram for each running application without gaining any beneift, unless the app actually makes use of 64bit registers… so effectively you only waste memory. It is a hard requirement on systems with more than 4GB of ram and it surely makes sense for software that has been specifically written for 64bit register usage though.

What i plan to work on in the nearer future is a classic image to provide along with the Ubuntu Core image though (but under the same restrictions, only until an actual Ubuntu image exists).