** Changed in: linux-raspi (Ubuntu)
       Status: New => Confirmed

** Also affects: linux-raspi (Ubuntu Focal)
   Importance: Undecided
       Status: New

** Also affects: linux-raspi (Ubuntu Hirsute)
   Importance: Undecided
       Status: Confirmed

** Also affects: linux-raspi (Ubuntu Groovy)
   Importance: Undecided
       Status: New

-- 
You received this bug notification because you are a member of Kernel
Packages, which is subscribed to linux-raspi in Ubuntu.
https://bugs.launchpad.net/bugs/1914608

Title:
  no console during boot on UC20

Status in linux-raspi package in Ubuntu:
  Confirmed
Status in linux-raspi source package in Focal:
  New
Status in linux-raspi source package in Groovy:
  New
Status in linux-raspi source package in Hirsute:
  Confirmed

Bug description:
  when booting UC20 on a Pi4 the screen backlight is completely off and
  no signal is produced.

  inspecting the boot a little closer it seems the necessary modules for
  bringing up the vc4 framebuffer are not included in the initramfs on
  ubuntu core. once they get loaded (after boot) the backlight and
  signal turn on. The initrd should include the modules and load them
  during boot.

  this is also required to bring any kind of bootsplash back to UC20
  which is a reason all our digital signage customers currently hold
  back on going forward to UC20.

  the modules required are:

  ogra@ubuntu:~$ lsmod|grep vc4
  vc4                   290816  3
  drm_kms_helper        225280  3 vc4
  snd_soc_core          262144  1 vc4
  snd_pcm               143360  5 vc4,snd_bcm2835,snd_soc_core,snd_pcm_dmaengine
  drm                   565248  7 gpu_sched,drm_kms_helper,v3d,vc4

  the loading during boot in the journal is shown below:

  ogra@ubuntu:~$ sudo journalctl -b | grep vc4
  Apr 01 17:23:45 ubuntu kernel: vc4-drm gpu: bound fe600000.firmwarekms (ops 
vc4_fkms_ops [vc4])
  Apr 01 17:23:45 ubuntu kernel: fb0: switching to vc4drmfb from simple
  Apr 01 17:23:45 ubuntu kernel: [drm] Initialized vc4 0.0.0 20140616 for gpu 
on minor 1
  Apr 01 17:23:45 ubuntu kernel: vc4-drm gpu: fb0: vc4drmfb frame buffer device

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux-raspi/+bug/1914608/+subscriptions

-- 
Mailing list: https://launchpad.net/~kernel-packages
Post to     : kernel-packages@lists.launchpad.net
Unsubscribe : https://launchpad.net/~kernel-packages
More help   : https://help.launchpad.net/ListHelp

Reply via email to