Created attachment 125544 [details] dmesg with drm.debug=1 The computer running Ubuntu is being used as HTPC connected via HDMI to a screen projector. After upgrading to 16.04, it's unusable under production kernel. The screen starts flickering after a while (it's easily triggered by fast scrolling e.g. terminal's window). The whole screen get's filled with a noise, and then the projector gets disconnected for a while. The computer runs fine on an older kernel (4.2.0-35), it's still broken on the mainline kernel 4.7.0. Linux version 4.7.0-040700-generic (kernel@tangerine) (gcc version 5.4.0 20160609 (Ubuntu 5.4.0-6ubuntu1) ) #201608011546 SMP Mon Aug 1 19:48:41 UTC 2016 Attaching dmesg output
Does i915.enable_psr=0 or i915.enable_fbc=0 fix the issue? Please try them separately.
None of those options seem to help with the issue. I've added them as below: linux /boot/vmlinuz-4.7.0-040700-generic root=UUID=98e2c9a3-1a1a-4d21-b370-79d0cde7b5f2 ro quiet splash i915.enable_fbc=0 $vt_handoff
What is model and and CPU used?
(In reply to Jani Saarinen from comment #3) > What is model and and CPU used? from kernel log: CPU0: Intel(R) Core(TM) i7-4770T CPU @ 2.50GHz (family: 0x6, model: 0x3c, stepping: 0x3)
(In reply to Piotr Wieczorek from comment #2) > None of those options seem to help with the issue. > > I've added them as below: > linux /boot/vmlinuz-4.7.0-040700-generic > root=UUID=98e2c9a3-1a1a-4d21-b370-79d0cde7b5f2 ro quiet splash > i915.enable_fbc=0 $vt_handoff Hello Piotr, could you try with latest Kernel version? 4.10, there are a lot of patches merged recently. Please let us know if you still facing the issue.
I've just tested kernel 4.10.1 and the same problem still occurs.
Just wanted to let you guys know this issue is still happening. On Fedora 25 with kernel 4.10: https://vimeo.com/210734226.
CPU: Core i7 6700.
(In reply to Behrang Saeedzadeh from comment #7) > Just wanted to let you guys know this issue is still happening. On Fedora 25 > with kernel 4.10: https://vimeo.com/210734226. Per the video, doesn't look like a display issue to me at all.
To get clarity, can you re-test with latest drm-tip if issue still there?
I've tested it using kernel from http://kernel.ubuntu.com/~kernel-ppa/mainline/drm-tip/2017-05-24/ , that is 4.12.0-994_4.12.0-994.201705232315 and the glitches are still there. You can see the flickering here: http://www.youtube.com/watch?v=-u0vmw9mze8&t=0m12s
The following resolutions fail to display properly (noticeable screen flickering) Haswell 1920x1080i @ 60Hz / HDMI, display less than 4k + DP with VGA dongle 1920x1080i @ 50Hz / HDMI, display less than 4k + DP with VGA dongle 720x576i @ 50Hz / DP with HDMI dongle display 4k and less than 4k 720x480i @ 60Hz / DP with HDMI dongle display 4k and less than 4k OS: Linux 4.10.0-19-generic x86_64 Ubuntu 17.04 64 bits Kernel: 4.12.0-rc3-drm-tip-ww2-commit-187376e+ X-Org: 1.19.99.1
Disregard the previous, it works at the specified configuration: Haswell 1920x1080i @ 60Hz / HDMI, display less than 4k + DP with VGA dongle - works 1920x1080i @ 50Hz / HDMI, display less than 4k + DP with VGA dongle - works 720x576i @ 50Hz / DP with HDMI dongle display 4k and less than 4k - works 720x480i @ 60Hz / DP with HDMI dongle display 4k and less than 4k - works OS: Linux 4.10.0-19-generic x86_64 Ubuntu 17.04 64 bits Kernel: 4.12.0-rc3-drm-tip-ww2-commit-187376e+ X-Org: 1.19.99.1
(In reply to Piotr Wieczorek from comment #11) > I've tested it using kernel from > http://kernel.ubuntu.com/~kernel-ppa/mainline/drm-tip/2017-05-24/ , that is > 4.12.0-994_4.12.0-994.201705232315 and the glitches are still there. > You can see the flickering here: > http://www.youtube.com/watch?v=-u0vmw9mze8&t=0m12s Hello Piotr, Could you check if the projector has a newer firmware and update it? Also, what is the resolution and frequency that your projector supports? Did you have the opportunity to test with other HW configurations (a monitor instead projector, new HDMI, just to be sure a different computer connected to the projector, etc)? Could you attach new dmesg with drm.debug=0xe with the latest kernel? And once provided the information, please change as REOPEN :) Thank you.
Hello Piotr, Due to the lack of response, I'm closing this bug assuming the problem was fixed because a newer kernel update or a HW change. Could you confirm this information? Otherwise please REOPEN this case. Thank you.
I've tried connecting using a different HDMI cable - it didn't help. I think the problem is that the DeepColor mode got turned on in the recent kernels. The difference in picture mode as reported by the projector between Windows, old Linux kernel and a new recent Linux kernel was DeepColor mode being turned either on and off. Turning off DeepColor mode on my amplituner seems to help. So it seems to be the same (or similar issue) as https://bugs.freedesktop.org/show_bug.cgi?id=101166
It seems to be a couple of patches proposed that didn't make it upstream yet related to deep color. https://patchwork.kernel.org/patch/9156647/ https://patchwork.kernel.org/patch/5124471/
First of all. Sorry about spam. This is mass update for our bugs. Sorry if you feel this annoying but with this trying to understand if bug still valid or not. If bug investigation still in progress, please ignore this and I apologize! If you think this is not anymore valid, please comment to the bug that can be closed. If you haven't tested with our latest pre-upstream tree(drm-tip), can you do that also to see if issue is valid there still and if you cannot see issue there, please comment to the bug.
Closing, please re-open if still occurs.
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