Can't set refresh rate higher than 120Hz on 4k-144Hz display

[RChaintreuil]

Hi,

First of all, thank you for your work, and sorry if this is not the right component to file this issue against. I couldn't find a similar issue, except maybe #16, but it didn't seem to be the same.

I own a 4k144Hz display, that I drive from an AMD RX6900XT using DisplayPort. On every system I've used (Windows, Debian, Fedora, Arch) and every DE on Wayland (Gnome, KDE, hyprland), I was always able to set the refresh rate to 144Hz at 4k. But Cosmic isn't able to do so, and I can only set refresh rates up to 120Hz.

Trying the system display settings, the "143.999 Hz" option shows up, but doesn't do anything when I select it.
Using cosmic-randr gives me this output:

remi@fedora:~$ cosmic-randr list
DP-3 (enabled)
  Model:
  Physical Size: 630 x 360 mm
  Position: 0,0
  Scale: 200%
  Transform: normal
  Adaptive Sync: false

  Modes:
    3840x2160 @ 143.999 Hz (preferred)
    3840x2160 @ 120.000 Hz (current)
    3840x2160 @ 119.999 Hz
    3840x2160 @ 119.880 Hz
    3840x2160 @ 119.000 Hz
    3840x2160 @  60.000 Hz
    3840x2160 @  59.940 Hz
    2560x1440 @ 143.856 Hz
    2560x1440 @ 119.879 Hz
    2560x1440 @  59.940 Hz
    1920x1200 @  60.000 Hz
    1920x1080 @ 143.853 Hz
    1920x1080 @ 120.000 Hz
    1920x1080 @ 119.880 Hz
    1920x1080 @  60.000 Hz
    1920x1080 @  59.940 Hz
    1680x1050 @  59.954 Hz
    1600x1200 @  60.000 Hz
     1440x900 @  59.887 Hz
    1280x1024 @  60.020 Hz
     1280x800 @  60.000 Hz
     1280x720 @ 120.000 Hz
     1280x720 @ 119.880 Hz
     1280x720 @  60.000 Hz
     1280x720 @  59.940 Hz
     1024x768 @  75.029 Hz
     1024x768 @  60.004 Hz
      800x600 @  75.000 Hz
      800x600 @  60.317 Hz
      720x480 @  60.000 Hz
      720x480 @  59.940 Hz
      640x480 @  75.000 Hz
      640x480 @  60.000 Hz
      640x480 @  59.940 Hz

remi@fedora:~$ cosmic-randr mode DP-3 3840 2160 --refresh 143.999
Error: "configuration failed"

The same issue happens with wdisplays, which tells me the display server couldn't process the changes, and wlr-randr doesn't work either.
I've tried disabling Adaptive Sync to see if it helped, to no avail.

Is this a known issue? Is there a log file I can provide that could help diagnose what's wrong?

Thanks again.

[Drakulix]

Can you post these logs, after trying to set 144hz (either in cosmic-settings, cosmic-randr or wdisplays): journalctl --user _EXE=/usr/bin/cosmic-comp?

Do you have any other displays plugged in? I wonder if this is a bandwidth issue.

Could you also please post the output of drm_info on cosmic and any other desktop where it is working?

[RChaintreuil]

Thanks for the quick response.
Here's the output of the journal just after boot and trying to set the refresh rate twice through cosmic-randr:

-- Boot 277a739e5dd14813a9c784281d0bb513 --
May 16 10:30:19 fedora cosmic-comp[1330]: Failed to read config 'workspaces'
May 16 10:30:19 fedora cosmic-comp[1330]: Key-Binding 'Period' only matched case insensitive for "period"
May 16 10:30:19 fedora cosmic-comp[1330]: Key-Binding 'Comma' only matched case insensitive for "comma"
May 16 10:30:19 fedora cosmic-comp[1330]: Key-Binding 'Period' only matched case insensitive for "period"
May 16 10:30:19 fedora cosmic-comp[1330]: Key-Binding 'Comma' only matched case insensitive for "comma"
May 16 10:30:19 fedora cosmic-comp[1330]: Unable to become drm master, assuming unprivileged mode
May 16 10:31:33 fedora cosmic-comp[1330]: Failed to apply config to DP-3. Resetting
May 16 10:32:41 fedora cosmic-comp[1330]: Failed to apply config to DP-3. Resetting

I don't have any other monitor plugged in.
It might be a bandwidth issue, or maybe DSC? Even 120Hz creates random glitches and the display turning off and on, which no other environment does.
Adding drm_info from cosmic.
drm_info_cosmic.log

[RChaintreuil]

And here's the drm_info from Gnome 46 on Wayland.
drm_info_gnome.log

[RChaintreuil]

For information, I'm using a Gigabyte M28U, which has an RGB subpixel layout. I find it strange that cosmic is using the ABGR2101010 format on Plane 5, but I don't know if that could cause the issue.

[Drakulix]

kwin does as well and as far as I know, using an opaque format here should not affect bandwidth. On the other hand what definitely does is the use of more overlay planes. Cosmic might not be aggressively enough disable them to make the higher refresh rate work. I will investigate that, thanks for the logs, they already provide some good insight!

[FrankAlbella]

I can confirm the same on an AW3552QF, it shows a 4K 240hz option but fails to switch to it. Working fine on Gnome wayland (Pop on Wayland) on Pop!_OS 22.04.

[ChaosBlades]

Same issue on Samsung LS49CG954SNXZA
5120x1440 @ 239.999 Hz
Aug 11 20:27:05 pop-os cosmic-comp[2082]: Failed to apply config. Resetting

No issues on Gnome or KDE under X11 or Wayland.
I am also on a 6900XT

[SteamRex25]

I have the same issue with my asus tuff gaming 144hz 1440p monitor. only occurs under cosmic as kde works just fine.

Specs:
ryzen 5 3600,
rtx 3070,
32GB ddr4 3200 MT/s ram
Msi b550m pro vdh wifi motherboard

[Syntist]

Same Issue here with my display, 1440p 165h, only occurs under cosmic as, kde and gnome works fine.
Cosmic DE Alpha 5

Monitor: Acer Technologies EI322QUR
Specs:
I7 12th gen
A1000 + Intel Xe
16gb ram
Dell Precision 5570

[ChaosBlades]

pop-os/cosmic-comp#969

S76 knows why this is happening.