@waveform The issue might be with the bcm2711-rpi-4-b.dtb...
sudo dpkg -i linux-firmware-raspi2_5-0ubuntu0~21.04~ppa1_arm64.deb ; sudo flash-kernel --force 5.11.22-9021-raspi ; sudo reboot
Result: no video.
sudo dpkg -i linux-firmware-raspi2_5-0ubuntu1~ppa1_arm64.deb ; sudo flash-kernel --force 5.11.22-9021-raspi ; sudo reboot
cd /boot ; sudo cp dtb-5.11.22-9021-raspi /boot/firmware/bcm2711-rpi-4-b.dtb ; sudo reboot
Result: Video!
sudo flash-kernel ; cd /boot ; sudo cp dtb-5.11.22-9021-raspi /boot/firmware/bcm2711-rpi-4-b.dtb ; sudo reboot
So maybe there's an issue with the bcm2711-rpi-4-b.dtb which the newer firmwares are installing causing issues with the newer kernels?
Working firmware versions I am seeing that work with the older 5.11 bcm2711-rpi-4-b.dtb:
sudo vcgencmd version Aug 31 2021 14:52:47 Copyright (c) 2012 Broadcom version 67615e950e1e28b92dfae6303cf7a8b879a8908f (clean) (release) (start)
sudo vcgencmd version Sep 30 2021 19:21:03 Copyright (c) 2012 Broadcom version 51215b4f6e3966401ecd99652a35cf1c25069113 (clean) (release) (start)
@waveform The issue might be with the bcm2711- rpi-4-b. dtb...
sudo dpkg -i linux-firmware- raspi2_ 5-0ubuntu0~ 21.04~ppa1_ arm64.deb ; sudo flash-kernel --force 5.11.22-9021-raspi ; sudo reboot
Result: no video.
sudo dpkg -i linux-firmware- raspi2_ 5-0ubuntu1~ ppa1_arm64. deb ; sudo flash-kernel --force 5.11.22-9021-raspi ; sudo reboot
Result: no video.
cd /boot ; sudo cp dtb-5.11. 22-9021- raspi /boot/firmware/ bcm2711- rpi-4-b. dtb ; sudo reboot
Result: Video!
sudo flash-kernel ; cd /boot ; sudo cp dtb-5.11. 22-9021- raspi /boot/firmware/ bcm2711- rpi-4-b. dtb ; sudo reboot
Result: Video!
So maybe there's an issue with the bcm2711-rpi-4-b.dtb which the newer firmwares are installing causing issues with the newer kernels?
Working firmware versions I am seeing that work with the older 5.11 bcm2711- rpi-4-b. dtb:
sudo vcgencmd version 92dfae6303cf7a8 b879a8908f (clean) (release) (start)
Aug 31 2021 14:52:47
Copyright (c) 2012 Broadcom
version 67615e950e1e28b
sudo vcgencmd version 01ecd99652a35cf 1c25069113 (clean) (release) (start)
Sep 30 2021 19:21:03
Copyright (c) 2012 Broadcom
version 51215b4f6e39664