Arch Linux

omen-x

Member

Registered: 2018-01-13

Posts: 5

[SOLVED] Display flickering

Hello.
Recently I've installed fresh Arch with my old display(23'1920x1080) and GPU. Then I connected a new display(27'2560x1440) and GPU(radeon rx550). First boot(2560x1440) with new display and I have an issue with 'flickering'(mostly when using keyboard). I also tested on Windows and it works fine.
After some research I've found xrandr. Setting some specific resolutions(1920x1200 doesn't work), for example 1920x1080  and back to 2560x1440(xrandr --output DisplayPort-0 --primary --mode 2560x1440 --pos 0x0 --rotate normal --output DVI-D-0 --off --output HDMI-A-0 --off) solved the problem until next reboot or 'monitor sleep'.

GPU driver - "amdgpu"
I'm using i3wm and compton. Without running "compton" issues also can be reproduced.

Xorg.log

Output of "xdpyinfo | grep -B5 -A10 resolution" after boot(before running xrandr):

screen #0:
  dimensions:    2560x1440 pixels (675x380 millimeters)
  resolution:    96x96 dots per inch
  depths (7):    24, 1, 4, 8, 15, 16, 32
  root window id:    0x6c7
  depth of root window:    24 planes
  number of colormaps:    minimum 1, maximum 1
  default colormap:    0x20
  default number of colormap cells:    256
  preallocated pixels:    black 0, white 16777215
  options:    backing-store WHEN MAPPED, save-unders NO
  largest cursor:    128x128
  current input event mask:    0x7a8077

Output of "xdpyinfo | grep -B5 -A10 resolution" after running xrandr:

screen #0:
  dimensions:    2560x1440 pixels (677x381 millimeters)
  resolution:    96x96 dots per inch
  depths (7):    24, 1, 4, 8, 15, 16, 32
  root window id:    0x6c7
  depth of root window:    24 planes
  number of colormaps:    minimum 1, maximum 1
  default colormap:    0x20
  default number of colormap cells:    256
  preallocated pixels:    black 0, white 16777215
  options:    backing-store WHEN MAPPED, save-unders NO
  largest cursor:    128x128
  current input event mask:    0x7a8077

The only difference is dimensions field(physical size in mm).

Output of "xrandr"

Screen 0: minimum 320 x 200, current 2560 x 1440, maximum 16384 x 16384
DisplayPort-0 connected primary 2560x1440+0+0 (normal left inverted right x axis y axis) 597mm x 336mm
   2560x1440     74.97*+  59.95
   1920x1200     74.97
   1920x1080     60.00    60.00    50.00    59.94    30.00    29.97
   1600x1200     74.97
   1680x1050     59.95
   1280x1024     75.02    60.02
   1440x900      59.89
   1280x960      60.00
   1280x800      74.97
   1152x864      75.00
   1280x720      60.00    50.00    59.94
   1024x768      75.03    70.07    60.00
   832x624       74.55
   800x600       72.19    75.00    60.32    56.25
   720x576       50.00
   720x480       60.00    59.94
   640x480       75.00    72.81    66.67    60.00    59.94
   720x400       70.08
HDMI-A-0 disconnected (normal left inverted right x axis y axis)
DVI-D-0 disconnected (normal left inverted right x axis y axis)

Output of "dmesg | grep -ie fail -ie error -ie warn":

[    0.005414] ACPI BIOS Warning (bug): Optional FADT field Pm2ControlBlock has valid Length but zero Address: 0x0000000000000000/0x1 (20180810/tbfadt-624)
[    0.999287] RAS: Correctable Errors collector initialized.
[    3.386329] ccp 0000:09:00.2: psp initialization failed
[    3.749425] amdgpu: [powerplay] Failed to retrieve minimum clocks.
[    3.749426] amdgpu: [powerplay] Error in phm_get_clock_info
[    3.800502] platform regulatory.0: Direct firmware load for regulatory.db failed with error -2
[    3.800503] cfg80211: failed to load regulatory.db
[    4.781143] random: 7 urandom warning(s) missed due to ratelimiting

I also added '20-amdgpu.conf" into xorg.conf.d folder:

Section "Device"
    Identifier "AMD"
    Driver "amdgpu"
    #Implemented by compton?
    #Option "TearFree" "true"
EndSection

Section "Monitor"
  Identifier "Acer"
  #DisplaySize 597 336
EndSection

Section "Screen"
  Identifier "Screen1"
  Monitor "Acer"
  Device "AMD"
EndSection

Last edited by omen-x (2018-11-19 20:52:53)

V1del

Forum Moderator

Registered: 2012-10-16

Posts: 21,788

Re: [SOLVED] Display flickering

Rule out the usual suspects, use amdgpu.dc=0 and/or amdgpu.dpm=0 amdgpu.runpm=0 on your kernel params, in general see: https://wiki.archlinux.org/index.php/AM … leshooting

Might also simply be an issue with the 74Hz refreshrate, what happens if you explicitly use the 59.95Hz one?

Last edited by V1del (2018-11-19 09:25:09)

omen-x

Member

Registered: 2018-01-13

Posts: 5

Re: [SOLVED] Display flickering

amdgpu.dc=0 and/or amdgpu.dpm=0 amdgpu.runpm=0

Seems like it helped. Previously I tried only amdgpu.dc=0 and it won't work. Is it valid solution or workaround only? As I noticed in the article, it will disable audio trough HDMI and some dynamic power management

V1del

Forum Moderator

Registered: 2012-10-16

Posts: 21,788

Re: [SOLVED] Display flickering

Any kind of manual kernel parameters in this regard should always be considered workarounds, ideally relevant bugs are fixed in the kernel. I know there have been some reports with issues with dynamic power management in recent 4.19 kernels, so you can run with this, and maybe recheck behaviour on kernel updates

omen-x

Member

Registered: 2018-01-13

Posts: 5

Re: [SOLVED] Display flickering

Thanks a lot. I'll check it later