Gentoo Forums
Gentoo Forums
Gentoo Forums
Quick Search: in
amdgpu in kernel 4.15: HDMI monitor stuck in YPbPr
View unanswered posts
View posts from last 24 hours

 
Reply to topic    Gentoo Forums Forum Index Multimedia
View previous topic :: View next topic  
Author Message
Ant P.
Watchman
Watchman


Joined: 18 Apr 2009
Posts: 6920

PostPosted: Mon Feb 19, 2018 1:28 am    Post subject: amdgpu in kernel 4.15: HDMI monitor stuck in YPbPr Reply with quote

I'm using an RX550, kernel 4.15.4, with the amdgpu DC kernel option enabled and amdgpu.audio=1.

After upgrading to 4.15 I've found my video card is mangling HDMI output. I have a dual-monitor arrangement and my main one (attached via DisplayPort) looks fine, but the HDMI-connected second one has visible colour sub-sampling artifacts - red text on a dark terminal looks particularly awful and shimmers when I drag the window on that screen.

I remember there used to be an xrandr property to switch the colour format between rgb/ypbpr/tv_rgb, but I just checked and it's not there any more:
Code:
 ~ $ xrandr --verbose
Screen 0: minimum 320 x 200, current 5760 x 2160, maximum 16384 x 16384
DisplayPort-0 connected primary 3840x2160+0+0 (0x58) normal (normal left inverted right x axis y axis) 600mm x 340mm
        Identifier: 0x54
        Timestamp:  2297116
        Subpixel:   unknown
        Gamma:      1.0:1.0:1.0
        Brightness: 1.0
        Clones:
        CRTC:       0
        CRTCs:      0 1 2 3 4
        Transform:  1.000000 0.000000 0.000000
                    0.000000 1.000000 0.000000
                    0.000000 0.000000 1.000000
                   filter:
        EDID:
                00ffffffffffff001e6d095bd95f0800
                [...]
                000000000000000000000000000000c8
        TearFree: on
                supported: off, on, auto
        underscan vborder: 0
                range: (0, 128)
        underscan hborder: 0
                range: (0, 128)
        underscan: off
                supported: off, on, auto
        scaling mode: None
                supported: None, Full, Center, Full aspect
        non-desktop: 0
                range: (0, 1)
        link-status: Good
                supported: Good, Bad
  3840x2160 (0x58) 533.250MHz +HSync -VSync *current +preferred
        h: width  3840 start 3888 end 3920 total 4000 skew    0 clock 133.31KHz
        v: height 2160 start 2214 end 2219 total 2222           clock  60.00Hz
  [...]
  640x480 (0x6c) 25.175MHz -HSync -VSync
        h: width   640 start  656 end  752 total  800 skew    0 clock  31.47KHz
        v: height  480 start  490 end  492 total  525           clock  59.94Hz
HDMI-A-0 connected 1920x1200+3840+0 (0x6d) normal (normal left inverted right x
axis y axis) 518mm x 324mm
        Identifier: 0x55
        Timestamp:  2297116
        Subpixel:   unknown
        Gamma:      1.0:1.0:1.0
        Brightness: 1.0
        Clones:
        CRTC:       1
        CRTCs:      0 1 2 3 4
        Transform:  1.000000 0.000000 0.000000
                    0.000000 1.000000 0.000000
                    0.000000 0.000000 1.000000
                   filter:
        EDID:
                00ffffffffffff0010ac16f04c4c3441
                [...]
                1800000000000000000000000000003e
        TearFree: on
                supported: off, on, auto
        underscan vborder: 0
                range: (0, 128)
        underscan hborder: 0
                range: (0, 128)
        underscan: off
                supported: off, on, auto
        scaling mode: None
                supported: None, Full, Center, Full aspect
        non-desktop: 0
                range: (0, 1)
        link-status: Good
                supported: Good, Bad
  1920x1200 (0x6d) 154.000MHz +HSync -VSync *current +preferred
        h: width  1920 start 1968 end 2000 total 2080 skew    0 clock  74.04KHz
        v: height 1200 start 1203 end 1209 total 1235           clock  59.95Hz
  [...]


There's nothing odd in dmesg or Xorg.0.log; X sees the display supports RGB 4:4:4 but isn't using it. I can't see anything DRM-related in /sys/ that'd let me change it either.

I've had similar problems with the radeon driver and HDMI in the past, but this is a new one to me.
Back to top
View user's profile Send private message
Display posts from previous:   
Reply to topic    Gentoo Forums Forum Index Multimedia All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum