[Intel Gemini Lake] No video signal during Plymouth or the (Wayland-based) login screen

[Agostinho Carvalho]

Hello.

I don't have any video during Ubuntu splash screen and also during the logon procedure.
I only have video in GRUB and after the logon operation takes place.
After I type in my password (in blind mode), Ubuntu will then start normally with correct video settings (resolution, etc...).

To workaround this error, I can either:

Workaround 1) Enable automatic login. That way the system doesn't get stuck in logon screen and Ubuntu loads immediately.
Problem: Boot splash won't be displayed anyway and I don't want this because I'm in a multi-user scenario.

Workaround 2) Add a kernel boot option "nomodeset" in /etc/default/grub
When I do this I will always get video signal.
Problem: The computer is an ECS Hybrid Device (tablet+detachable keyboard), and when I use this workaround, user session loads in Portrait mode (not Landscape) and there is no auto-rotation support.

Workaround 3) Although I don't have video signal during Boot Splash and Logon screen, I do have backlight continuously applied to the display.
If I wait 5 minutes or so in the logon screen the backlight will deactivate...
However, when I touch the keyboard or touchpad the computer will then show video signal and I will be able to see the logon screen perfectly.
Problem: I don't want to wait 5 minutes in the logon screen to obtain proper video signal.

Computer is this one:
https://www.ecs.com.tw/ECSWebSite/Product/Product_Overview/EN/Tablet%20PC/TH10GM2/10-inch%20Tablet%20PC

Specs are here:
https://www.ecs.com.tw/ECSWebSite/Product/Product_SPEC/EN/Tablet%20PC/TH10GM2/10-inch%20Tablet%20PC

Feel free to request any extra information.

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: xorg 1:7.7+19ubuntu14
ProcVersionSignature: Ubuntu 5.4.0-54.60-generic 5.4.65
Uname: Linux 5.4.0-54-generic x86_64
ApportVersion: 2.20.11-0ubuntu27.12
Architecture: amd64
CasperMD5CheckResult: skip
CompositorRunning: None
Date: Sun Nov 22 19:56:20 2020
DistUpgraded: Fresh install
DistroCodename: focal
DistroVariant: ubuntu
ExtraDebuggingInterest: Yes, including running git bisection searches
GraphicsCard: Intel Corporation UHD Graphics 605 [8086:3185] (rev 03) (prog-if 00 [VGA controller])
InstallationDate: Installed on 2020-11-22 (0 days ago)
InstallationMedia: Ubuntu 20.04.1 LTS "Focal Fossa" - Release amd64 (20200731)
MachineType: ECS CMPC
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.4.0-54-generic root=UUID=2e7d6b98-86c2-4579-bd7f-fa31664333f6 ro quiet video=efifb fbcon=rotate:1
SourcePackage: xorg
Symptom: display
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 10/15/2019
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 1.02.00.STD
dmi.board.asset.tag: Default string
dmi.board.name: ik Educational Software
dmi.board.vendor: ECS
dmi.board.version: Default string
dmi.chassis.asset.tag: Default string
dmi.chassis.type: 30
dmi.chassis.vendor: NULL
dmi.chassis.version: Default string
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr1.02.00.STD:bd10/15/2019:svnECS:pnCMPC:pvrDefaultstring:rvnECS:rnikEducationalSoftware:rvrDefaultstring:cvnNULL:ct30:cvrDefaultstring:
dmi.product.family: Default string
dmi.product.name: CMPC
dmi.product.sku: Default string
dmi.product.version: Default string
dmi.sys.vendor: ECS
version.compiz: compiz N/A
version.libdrm2: libdrm2 2.4.101-2
version.libgl1-mesa-dri: libgl1-mesa-dri 20.0.8-0ubuntu1~20.04.1
version.libgl1-mesa-glx: libgl1-mesa-glx N/A
version.xserver-xorg-core: xserver-xorg-core 2:1.20.9-2ubuntu1
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:19.1.0-1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20200226-1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.16-1

[Daniel van Vugt (vanvugt)]

This sounds like a kernel problem. And both plymouth and the login screen do use the same kernel interfaces...

First, please try removing these kernel parameters:

  video=efifb fbcon=rotate:1

and if that doesn't solve it please also try changing the kernel parameter "splash" to "nosplash".

Also you may be able to use this as a workaround for the login screen: Edit /etc/gdm3/custom.conf and change:

  #WaylandEnable=false

to

  WaylandEnable=false

[Agostinho Carvalho (agostinho-df-carvalho)]

Hi Daniel.

Boot Splash Issue:

I removed "video=efifb". That didn't help.
I applied "nosplash". That didn't help.
I removed "fbcon=rotate:1". That didn't help. Removing this last one made things a bit worse.
"fbcon=rotate:1" presence is necessary (at least in my system), otherwise, the console (during boot and shutdown) will present itself rotated 90 degrees counter-clockwise.
My screen is always in Portrait Mode by default (even in the BIOS) and this kernel boot flag changes it to Landscape Mode (at least during boot and shutdown operations) which is what I prefer.

So, unfortunately, these suggestions didn't help in the Boot Splash issue.

For your reference...
I also tried the following kernels without success:
5.6.0-1034-oem (focal-updates repo)
5.8.0-25-generic (groovy repo). I know that this kernel is not for Ubuntu 20.04.1LTS, but I was desperate.

I even tried Linux Mint 20 Ulyana Live. No boot splash as well. Didn't had the time to install it though.

------

Logon Screen Issue:

Editing /etc/gdm3/custom.conf and changing:
 #WaylandEnable=false
to
 WaylandEnable=false

It worked PERFECTLY !

For me, the boot splash issue is secondary when compared to the logon screen issue.
Thank you very much Daniel!

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This change was made by a bot.