It has bothered me that I keep reading that vc4-kms-v3d and vc4-kms-v3d-pi4 are redundant. However, on my system they behaved very differently, not only in results but on closer examination they load a very different set of kernel drivers.
Edit: Here is a link on github, it shows how this file is used and possible implications of adding it. It could have a user impact, if it were to be installed, depending on what people have set in config.txt.
Not that I have been able to find. Maybe it is deemed too technical? But raspistill is also not available and that is a desktop app. I am not sure why. Maybe no one asked for them?
In my interpretation, the word redundant, is not a great choice of words. If you use dtoverlay=vc4-kms-v3d and you are running on a RPi4, it will instead load vc4-kms-v3d-pi4. So if you are already using dtoverlay=vc4-kms-v3d-pi4 there will be no change with the inclusion of this file. The benefit is the single setting of dtoverlay=vc4-kms-v3d will load the correct file for both rpi3 and rpi4.
No. That was a ubuntu misque by naming it overlay_map.dtb so it got put in /boot/ with all of the other .dtb’s. It was supposed to be overlay_map.dtbo and go in /boot/overlays/.
All overlays go in /boot/overlays. All RPi specific device firmware (.dtb’s) go in /boot/. These directories are where the RPi devices knows to look for the files to be loaded automatically. You can specify paths but why not let the pi do what it does?.
This is a custom arch-arm 32 bit os I am on and the image boots more than one kernel so I had to do a separate pkgbuilld that just did overlays and .dtb’s. So guessing the mis-naming issue with RPi and me using *.dtbo to copy over to the pkg directory in the 64 bit kernel package.
After reading your link above a 2nd time it looks like it is really supposed to be overlay_map.dtb instead of overlay_map.dtbo in /boot/overlays. Rename the file and put it in /boot/overlays.
Quote (Ubuntu uses a different file structure):
Canonical are now aware of the problem and it should be fixed in future releases. For now you have the easy workaround of copying /boot/firmware/overlay_map.dtb into /boot/firmware/overlays/ after installation.
Not sure to understand everything… so here are my questions :
do we have to install this .dtb by our own ?
can you please look at the userland thing and see if we can get vcdbg ? BTW there are commits from january for this code, maybe at least you can update it ?