[SOLVED] Flickering & Blanking screen upon switching window

$this->bbcode_second_pass_quote('jyno', '')$this->bbcode_second_pass_quote('', '
')I modified by /boot/config/txt

from
dtoverlay=vc4-kms-v3d
to
dtoverlay=vc4-fkms-v3d

saved the file and rebooted, Flickering screen has gone

[jyno]

Can you downgrade the kernels for both linux-rpi and linux-rpi-legacy to a version where this doesn't occur?

[robg]

$this->bbcode_second_pass_quote('jyno', 'C')an you downgrade the kernels for both linux-rpi and linux-rpi-legacy to a version where this doesn't occur?

[darksky]

Until they fix the issue I apply this patch (put together from info they gave me to test) reverting the cause of the issue until they fix it. This works on the latest RPi 5.10, 5.15 and 5,16-rc kernels.

https://gitlab.manjaro.org/manjaro-arm/packages/core/linux-rpi4/-/blob/master/revert-gamma.diff

[graysky]

$this->bbcode_second_pass_quote('darksky', 'U')ntil they fix the issue I apply this patch (put together from info they gave me ) reverting the cause of the issue until they fix it. This works on the latest RPi 5.10, 5.15 and 5,16-rc kernels.

https://gitlab.manjaro.org/manjaro-arm/packages/core/linux-rpi4/-/blob/master/revert-gamma.diff

[darksky]

"Any ill-effects for other use cases? Does kodi which requires dtoverlay=vc4-kms-v3d and dtoverlay=rpivid-v4l2 work 100%?"

None that I can see. Been doing this for weeks now with my kernels. Kodi with dtoverlay=vc4-fkms-v3d and dtoverlay=rpivid-v4l2 also works well with HW decoding with h.264/h.265.

This flickering started when they tried to add gamma control (hue, tint....) All of my monitors has the capabilities to do this on their own so I do not need it and I have not had one complaint with the patch applied.

[graysky]

Thanks for confirming

[graysky]

I didn't completely follow the discussion in https://github.com/raspberrypi/linux/issues/4660 .. what is the status of this upstream?

[darksky]

I am unaware of anything upstream being done with these gamma commits. I do not follow upstream much other than testing how the upstream kernel works on the pi4 from time to time. Of course upstream does not have V3D so it always seem to work ok in my tests.

[graysky]

OK, I applied this to my rpi-5.15.y test kernel and kodi seems fine in some testing. For those affected, I also applied it to our repo kernels. Building now/should hit the repos shortly. Maybe someone affected by this bug can report back once it hits the repos?