Created attachment 141066 [details]
The xorg log
I have a really crappy Philips "HD ready" tv. This tv has no options to change the color format, and it always assumes full rgb. The problem is now that I upgraded my graphics card, and now with the RX 580 I'm using the amdgpu driver. amdgpu chooses YCrCb or limited RGB (but seemingly not reported as supported, so not likely) automatically instead of RGB, and all my colors look really bad. Black levels are grey and everything looks washed out and blurry.
From xorg log:
Information [ 6.523] (II) AMDGPU(0): Supported color encodings: RGB 4:4:4 YCrCb 4:4:4
If I use an adapter and plug it in via DVI instead of HDMI, it looks fine. That has its compromises though (I now have to connect my 2nd monitor by a VGA to HDMI adapter, and that has its issues). Kernel 4.18 also breaks this work-around; it doesn't recognize any resolutions, and seemingly no EDID at all. HDMI is same as before.
I also tried overriding the EDID and setting YCrCb as not supported, but failed
The solution to all of this hassle would be to have the option "output_csc" available on amdgpu as it's apparently possible with radeon
Please attach the corresponding dmesg output.
Does it work better with amdgpu.dc=0?
Created attachment 141164 [details]
dmesg with amdgpu.dc=0
Created attachment 141165 [details]
dmesg with amdgpu.dc=1
With amdgpu.dc=0 it seems to work just fine. I've booted up with my normal setup, switched the cables so I am connected by HDMI directly and I get good colors
I have the same problem
Same problem. Disabling DisplayCore gets me crisp and beautiful colors, but at the cost of audio over HDMI. Faded colors with dc=1 has been a longstanding issue for me.
Similar problem over here: everything works fine with amdgpu.dc=0. Without it the colors are way darker.