Cannot enable VC4 graphics driver on RPi 3

[Alberto Aguirre]

It seems the VC4 device tree overlay is not applied by the Rpi firmware.

I tried adding dtoverlay=vc4-kms-v3d and adding a corresponding .../overlays/vc4-kms-v3d.dtbo file but it seems the Rpi bootloader does not apply the overlay at all.

I merged vc4-kms-v3d.dtbo into bcm2710-rpi-3-b.dtb using a dtmerge utility compiled by pulling pieces from (https://github.com/raspberrypi/userland and https://github.com/dgibson/dtc)
The result is here: https://github.com/albaguirre/dtmerge

With this new device tree binary blob, The VC4 driver (as a module) loads (and you can see /dev/dri/ entries)

I also played around with the tip of u-boot tree (git://git.denx.de/u-boot.git) which has support to apply device tree overlays - it applied fine and VC4 is at least recognized but the driver cannot initialize properly.

Any idea on what magic incantation is needed for the RPi loaders (start.elf etc) to apply the vc4 overlay?

[Brad Figg (brad-figg)]

This bug is missing log files that will aid in diagnosing the problem. From a terminal window please run:

apport-collect 1655411

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.

[Oliver Grawert (ogra)]

where exactly did you add the overlays in the first paragraph ? only overlays in /boot/uboot/overlays are read by the proprietary bootloader (you need to create the dir)

[Oliver Grawert (ogra)]

ogra@pi3:~$ cd /boot/uboot/
ogra@pi3:~$ sudo tar xvf pi2-kernel_22.snap/dtbs/overlays.tgz

then adding "dtoverlay=vc4-kms-v3d" and creating /etc/modules-load.d/vc4.conf with just "vc4" in it seems to get me vc4 loaded and i get:

[ 4.952421] vc-cma: Videocore CMA driver
[ 4.956535] vc-cma: vc_cma_base = 0x00000000
[ 4.961451] vc-cma: vc_cma_size = 0x00000000 (0 MiB)
[ 4.967083] vc-cma: vc_cma_initial = 0x00000000 (0 MiB)
[ 4.972972] vc-mem: phys_addr:0x00000000 mem_base=0x3dc00000 mem_size:0x3f000000(1008 MiB)
...
[ 6.036262] vc-sm: Videocore shared memory driver
[ 6.036269] [vc_sm_connected_init]: start
[ 6.036676] [vc_sm_connected_init]: end - returning 0
...
[ 10.229614] [drm] Initialized drm 1.1.0 20060810

i assume we also need to set gpu_mem in config.txt

[Alberto Aguirre (albaguirre)]

Turns out we simply need to use the latest firmware loader blobs, then the vc4 overlay is applied correctly while using u-boot.

https://github.com/raspberrypi/firmware/tree/master/boot

[Launchpad Janitor (janitor)]

[Expired for linux (Ubuntu) because there has been no activity for 60 days.]