Baytrail "Toshiba Chromebook 2" "Swanky"
Samsung U28E590D UHD 4K
HDMI connection (HDMI 2 on screen)
Wayland
Fedora devel

xrandr --verbose
xrandr --verbose
Screen 0: minimum 320 x 200, current 1920 x 2160, maximum 8192 x 8192
XWAYLAND0 connected 1920x1080+0+0 (0x24) normal (normal left inverted right x axis y axis) 610mm x 350mm
	Identifier: 0x21
	Timestamp:  44556
	Subpixel:   unknown
	Gamma:      1.0:1.0:1.0
	Brightness: 0.0
	Clones:    
	CRTC:       0
	CRTCs:      0
	Transform:  1.000000 0.000000 0.000000
	            0.000000 1.000000 0.000000
	            0.000000 0.000000 1.000000
	           filter: 
  1920x1080 (0x24) 173.000MHz -HSync +VSync *current +preferred
        h: width  1920 start 2048 end 2248 total 2576 skew    0 clock  67.16KHz
        v: height 1080 start 1083 end 1088 total 1120           clock  59.96Hz
XWAYLAND1 connected 1920x1080+0+1080 (0x24) normal (normal left inverted right x axis y axis) 290mm x 170mm
	Identifier: 0x23
	Timestamp:  44556
	Subpixel:   unknown
	Gamma:      1.0:1.0:1.0
	Brightness: 0.0
	Clones:    
	CRTC:       1
	CRTCs:      1
	Transform:  1.000000 0.000000 0.000000
	            0.000000 1.000000 0.000000
	            0.000000 0.000000 1.000000
	           filter: 
  1920x1080 (0x24) 173.000MHz -HSync +VSync *current +preferred
        h: width  1920 start 2048 end 2248 total 2576 skew    0 clock  67.16KHz
        v: height 1080 start 1083 end 1088 total 1120           clock  59.96Hz

Created attachment 134256 [details]
lspci

Created attachment 134257 [details]
Boot log

Created attachment 134258 [details]
dmesg

Baytrail doesn't support 4k HDMI. The maximum pixel clock you can push through the HDMI port is 225MHz, which limits you to ~2400x1300 max resolution (assuming 16:9 aspect ratio). 4k would be possible over DP.

Well 2400x1300 would still be better than 1920x1080

I suppose an hdmi do display port converter won't allow going further, the limit is in the chipset hdmi support ?

(In reply to Nicolas Mailhot from comment #6)
> Well 2400x1300 would still be better than 1920x1080

Between 3840x2160 and 1920x1080 your display only supports 2560x1440 which also requires a pixel clock too high for your Baytrail.

> I suppose an hdmi do display port converter won't allow going further, the
> limit is in the chipset hdmi support ?

Correct. You might get it to work using a DP to HDMI active protocol converter, but truthfully there have been issues with them too.

It's still NOTABUG.