Intel 8K Display Support Should Be Working With Linux 5.4

[phoronix]

Phoronix: Intel 8K Display Support Should Be Working With Linux 5.4

On top of the many Linux 5.4 features we have been talking about so far, it turns out with this kernel update due out in November that 8K display support for Intel (Gen11 Icelake and newer) should be in order...

http://www.phoronix.com/scan.php?page=news_item&px=Linux-5.4-Intel-8K-DP-Working

[hrkristian]

Meanwhile Intel GPUs running underneath X still does not have the ability to render a total desktop size larger than 8192x8192. Thankfully it works just fine on Wayland. Perhaps that's also fixed with this...

[mastermind]

It's surprising that this tearing issue with tiled monitors is being fixed just now on Intel GPUs. Nvidia proprietary blob has been handling these properly for years (5K and 8K tiled Dell monitors at least). There is another issue though: Nvidia driver exposes these monitors as 2 separate CRTCs (left and right halves) to X/RANDR which causes all kinds of problems. (most of which can be resolved with a library called hax11 however) Does anyone know what's Intel's approach to this? Do they expose one (whole screen) or two CRTCs (left and right halves) to X/RANDR?
Also, I never got around to trying these monitors with AMD GPUs. Do AMD drivers handle tiled monitors properly? Anyone?

[syrjala]

Meanwhile Intel GPUs running underneath X still does not have the ability to render a total desktop size larger than 8192x8192. Thankfully it works just fine on Wayland. Perhaps that's also fixed with this...

Rendering limit was already 16kx16k on modern hw, the display was limited to 8kx8k. We got rid of that limit in 5.3 and now the display can handle 16kx16k framebuffers as well on ivb+ (though not as efficiently as it can handle smaller ones).

[agd5f]

Also, I never got around to trying these monitors with AMD GPUs. Do AMD drivers handle tiled monitors properly? Anyone?

Yes. The tiling property is exposed to userspace and desktop environments can use it to set screen geometry independent of the drivers. Typically large displays are DP MST and a separate display controller handles each part (as if they were independent monitors). Additionally, there is sync lock hw in the display controller which allows the driver to synchronize the scanout of displays with identical modelines so they will always be vsync aligned.