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Cezanne APU fails to resolve refresh rate properly on Lenovo Legion 5 (16ACH6H).

Brief summary of the problem:

Lenovo Legion 5 (16ACH6H) has a display which supports refresh rates of 60hz and 165hz . When using hybrid graphics xrandr does not acknowledge the existence of 165hz mode. I tried to add a newmode via xrandr --newmode "2560x1600_165.00" 1047.00 2560 2800 3080 3600 1600 1603 1609 1763 -hsync +vsync. That did not work . My screen went blank . A similar incident was reported here.When using discrete graphics(NVIDIA RTX 3060) 165hz works out of the box. It's also the default refresh rate. On Microsoft Windows 10 165hz refresh rates works on both hybrid and discrete graphics mode.

Hardware description:

  • CPU: AMD Ryzen 7 5800H with Radeon Graphics
  • GPU: 01:00.0 VGA compatible controller [0300]: NVIDIA Corporation GA106M [GeForce RTX 3060 Mobile / Max-Q] [10de:2560] (rev a1) 05:00.0 VGA compatible controller [0300]: Advanced Micro Devices, Inc. [AMD/ATI] Cezanne [1002:1638] (rev c5)
  • System Memory: 16Gib, (1Gib allocated to integrated gpu)
  • Display(s): 16.00 inch 16:10, 2560 x 1600 pixel 189 PPI, CSOT T3 MNG007DA1-1, IPS, Dolby® Vision™, VESA HDR 400, free sync, G Sync, DC dimmer, glossy: no, HDR, 165 Hz? Taken form here
  • Type of Display Connection: eDP

System information:

  • Distro name and Version: Archlinux
  • Kernel version: 5.14.12-zen1-1-zen also tested on linux-5.15rc6 and linux-next-git-20211019.r0.g5b27c149257d-1-x86_64
  • Mesa version: 21.3.0-devel (git-783f8f728c)

How to reproduce the issue:

  • Set hybrid graphics mode in UEFI
  • Boot

Attached files:

Log files