[Lenovo Yoga Slim 7 14IIL05] PSR causes incomplete screen redraws

Thanks for the bug report. This sounds like several unrelated issues. Please choose a single issue for this bug to be about.

Also the tearing and laggy performance is caused by your kernel parameter "nomodeset". Please remove that.

After removing nomodeset my pc fail to start and frezzes on boot and sometime touchpad and brightness control from my laptop keys stop working.

OK. Those are probably all different issues though. So let's focus on:

> my pc fail to start and frezzes on boot

Please:

1. Reproduce the boot failure again, without "nomodeset".

2. Wait 10 seconds.

3. Reboot with "nomodeset".

4. Run:

   journalctl -b-1 > prevboot.txt

5. Attach the resulting text file here.

Hey, I have already remove nomodeset from grub before submitting bug report.
But screen tearing is there.
Booting is perfectly fine except display glitch.

OK then let's make the display glitches the main issue here.

Since the PC is booting fine, please now run:

  journalctl -b0 > journal.txt
  xrandr --verbose > xrandr.txt

and attach the resulting text files here.

Please also take a video of the issue if you can so we can better understand the problems you're seeing.

Thanks. It looks like you've tried both Xorg and Wayland sessions. Are the bugs the same in both?

Please try:

* Installing the proprietary Nvidia driver via the 'Additional Drivers' app. The open source nouveau driver is frequently buggy so I would like to eliminate that from the equation ASAP.

* Looking in your BIOS and see if you can disable the discrete Nvidia GPU temporarily. Does that fix it?

List of things I have to Inform you what I have tested.I am Computer Science student but new to linux so I have tested many things.

1. I have used both x-org and nvidia GPU.
        After fresh installation and on reboot I got into many problem my touchpad and brightness controller were not working and screen glitch so i fixed my brightness and touchpad using ubuntu community posts. But glitch were all same I have tried many solution but not solved.
so I posted ubuntu-bug.

2. I have changed setting from bios to disable NVIDIA but glitch problem not solved.
  And on using NVIDIA Driver there were not glitch performance were perfectly fine but on restart
   i got stucked on boot menu screen were blank so i ran into recovery and change my driver to x-org intel.

3. Before bug submission I have tested around 10 popular linux distro all were having same problem screen glitches.

4. only two distro have not occoured a display glitch problem one was ubuntu 20.04 LTS and ubuntu budgie 21.04 but that distro causes same touchpad and brightness controll problem that was so frustating. So I came to conclusion that my intel driver is buggy and on reboot my device alwaay fail to recognise touchpad and display driver.

It looks like this might be a Panel Self Refresh bug. PSR was disabled in Ubuntu 20.04 but seems to be enabled (sometimes) in newer Ubuntu releases. So please try disabling it by adding a kernel parameter:

  i915.enable_psr=0

This post seems to confirm your model of laptop has issues with PSR on Linux:

https://www.reddit.com/r/archlinux/comments/jzhwmv/graphical_glitches_on_arch_running_kde_520_on_new/

so the workaround should be:

  i915.enable_psr=0

But please confirm.

Also the touchpad issue is bug 1899913.

As you said to change the i915.enable_psr =0 i have save it to suno nano etc/kernal/cmdline after rebooting my pc there is more screen tearing problem.

yeah i am using ubuntu in 2 device one in my old lenovo g570 model and new lenovo yoga 7i and in G570 there is no problem such as screen tearing or brightness every thing is perfectly fine in g570

i think there is some issue with intel gpu driver because sometime ubuntu stuck on bootscreen and glitches and tearing is common in every scenario and after booting to recovery boot brightness controlling have some issue and all tends towards the ghraphics bug.

Please check /proc/cmdline and verify it contains the new parameter: i915.enable_psr=0

You may need to run:

  sudo update-grub

and reboot again before it starts working.

Also

> after booting to recovery boot brightness controlling have some issue

is not a bug. It's expected behaviour in recovery mode.

Another simple test to verify you've set the parameter is to run:

  sudo cat /sys/module/i915/parameters/enable_psr

It should print zero.

It said -1

Please tell me proper procedure to change value to zero

I would edit /etc/default/grub and add i915.enable_psr=0 to the GRUB_CMDLINE_LINUX_DEFAULT line.

Then run:

  sudo update-grub

and reboot.

yes ! I am Gonna tell you that same Now its perfectly fine no glitches and tearing issue now.But I want to Know does touchpad issue is solved in UBuntu 20.04LTS for lenovo yoga 7

Please keep all discussion about the touchpad in bug 1899913.

Please test latest drm-tip kernel:
https://kernel.ubuntu.com/~kernel-ppa/mainline/drm-tip/current/

Headers are not needed.

I'm not sure we need to bother with the above. We already know PSR is the cause of the problem. I was assuming it just needs to be disallowed for this machine... unless it can be *fixed* somehow in later kernels without being disabled?

Mainly to test "drm/i915/display: Disable PSR2 if TGL Display stepping is B1 from A0", though the CPU seems to be ICL.

Can you tell me in brief how to test drm-tip kernal and disble PSR2

You need to download at least two files:

https://kernel.ubuntu.com/~kernel-ppa/mainline/drm-tip/2021-08-09/amd64/linux-image-unsigned-5.14.0-051400rc5drmtip20210809-generic_5.14.0-051400rc5drmtip20210809.202108082205_amd64.deb

https://kernel.ubuntu.com/~kernel-ppa/mainline/drm-tip/2021-08-09/amd64/linux-modules-5.14.0-051400rc5drmtip20210809-generic_5.14.0-051400rc5drmtip20210809.202108082205_amd64.deb

and then install them together:

  sudo dpkg -i linux*drmtip20210809*.deb

before Testing one thing I want to tell you I won't able to boot in ubuntu in normal mode but in recovery mode there is no issue related to screen tearing

Yes we know. Recovery mode works by disabling performance and power saving features so it will work around this bug. But that's not relevant to actually fixing the bug. Nobody should stay in recovery mode long term.

I have installed both files, Now what to do??

Now I am able to boot into ubuntu in normal mode but there is screen glitch problem.

OK, please verify the kernel version you're seeing the glitch in by running:

  uname -a

Linux YOGA 5.14.0-051400rc5drmtip20210809-generic #202108082205 SMP Mon Aug 9 02:21:27 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux

Thanks for doing that.

It would seem the only fix is still 'i915.enable_psr=0' so please continue using that.

Please file a bug against Intel graphics:
https://gitlab.freedesktop.org/drm/intel/wikis/How-to-file-i915-bugs

I had exact same issue on ubuntu 20.04 with same system "lenovo yoga slim7 14IIL05"
Putting "i915.enable_psr=0" to GRUB_CMDLINE_LINUX_DEFAULT fixed issues such as rendering, screen tearing, delaying.

The same issue on ubuntu 20.04(5.13.0-30) on Yoga slim 9 14ITL

Putting "i915.enable_psr=0" to GRUB_CMDLINE_LINUX_DEFAULT fixed issues such as rendering, screen tearing, delaying.