[mythtv-users] Problem with TV resolution after upgrading to 20.04

[Stephen Worthington]

On Fri, 9 Oct 2020 17:02:04 -0500, you wrote:

>>On Fri, 9 Oct 2020 12:11:36 -0500, Stephen Worthington wrote:
>>
>>>I've recently upgraded (fresh install) of Xubuntu 20.04. I'd been
>>>using Ubuntu (desktop) for almost 10 years, but recently the gnome
>>>desktop has been giving me fits.  I had Xubuntu on my remote frontend,
>>>and that installation was a charm, fixing all the problems with menu
>>>bars.
>>>
>>>So, the installation went well with the exception of losing a power
>>>supply in one of my disk arrays (fixed and the raid arrays are all
>>>online) but I still have problems with the part that everyone using
>>>the system looks at: the TV.  I set the display to 3840x2160 in the
>>>desktop and told it to hide the menu bar and it looked great! Until I
>>>turned the TV off and back on.  It had changed the resolution to
>>>1920x1080.
>>>
>>>After some digging I found the issue with X.  In the Xorg.log.0 file I
>>>see this after switching the display to the proper resolution:
>>>
>>>[ 52764.156] (--) NVIDIA(GPU-0): DFP-0: disconnected
>>>[ 52764.156] (--) NVIDIA(GPU-0): DFP-0: Internal TMDS
>>>[ 52764.156] (--) NVIDIA(GPU-0): DFP-0: 165.0 MHz maximum pixel clock
>>>[ 52764.156] (--) NVIDIA(GPU-0):
>>>[ 52764.186] (--) NVIDIA(GPU-0): DENON, Ltd. DENON-AVR (DFP-1): connected
>>>[ 52764.186] (--) NVIDIA(GPU-0): DENON, Ltd. DENON-AVR (DFP-1): Internal TMDS
>>>[ 52764.186] (--) NVIDIA(GPU-0): DENON, Ltd. DENON-AVR (DFP-1): 600.0
>>>MHz maximum pixel clock
>>>[ 52764.186] (--) NVIDIA(GPU-0):
>>>[ 52764.241] (II) NVIDIA(0): Setting mode "HDMI-0: 3840x2160
>>>@3840x2160 +0+0 {ViewPortIn=3840x2160, ViewPortOut=3840x2160+0+0}"
>>>
>>>Then after turning the TV off I see this:
>>>
>>>[ 52827.478] (--) NVIDIA(GPU-0): DFP-0: disconnected
>>>[ 52827.478] (--) NVIDIA(GPU-0): DFP-0: Internal TMDS
>>>[ 52827.478] (--) NVIDIA(GPU-0): DFP-0: 165.0 MHz maximum pixel clock
>>>[ 52827.478] (--) NVIDIA(GPU-0):______
>
>>>[ 52827.508] (--) NVIDIA(GPU-0): DENON, Ltd. DENON-AVR (DFP-1): connected
>>>[ 52827.508] (--) NVIDIA(GPU-0): DENON, Ltd. DENON-AVR (DFP-1): Internal TMDS
>>>[ 52827.508] (--) NVIDIA(GPU-0): DENON, Ltd. DENON-AVR (DFP-1): 600.0
>>>MHz maximum pixel clock
>>>[ 52827.508] (--) NVIDIA(GPU-0):
>>>[ 52827.543] (II) NVIDIA(0): Setting mode "HDMI-0: nvidia-auto-select
>>>@1920x1080 +0+0 {ViewPortIn=1920x1080, ViewPortOut=1920x1080+0+0}"
>>>
>>>And there it stays until I go back into the display properties and put it back.
>>>
>>>I also noticed this declaration in the Xorg.log.0 file:
>>>
>>>[ 52762.997] (--) NVIDIA(GPU-0): DFP-0: disconnected
>>>[ 52762.997] (--) NVIDIA(GPU-0): DFP-0: Internal TMDS
>>>[ 52762.997] (--) NVIDIA(GPU-0): DFP-0: 165.0 MHz maximum pixel clock
>>>[ 52762.997] (--) NVIDIA(GPU-0):
>>>[ 52763.027] (--) NVIDIA(GPU-0): DENON, Ltd. DENON-AVR (DFP-1): connected
>>>[ 52763.027] (--) NVIDIA(GPU-0): DENON, Ltd. DENON-AVR (DFP-1): Internal TMDS
>>>[ 52763.027] (--) NVIDIA(GPU-0): DENON, Ltd. DENON-AVR (DFP-1): 600.0
>>>MHz maximum pixel clock
>>>[ 52763.027] (--) NVIDIA(GPU-0):
>>>[ 52763.031] (==) NVIDIA(0):
>>>[ 52763.032] (==) NVIDIA(0): No modes were requested; the default mode
>>>"nvidia-auto-select"
>>>[ 52763.032] (==) NVIDIA(0):     will be used as the requested mode.
>>>[ 52763.032] (==) NVIDIA(0):
>>>[ 52763.032] (II) NVIDIA(0): Validated MetaModes:
>>>[ 52763.032] (II) NVIDIA(0):     "DFP-1:nvidia-auto-select"
>>>[ 52763.032] (II) NVIDIA(0): Virtual screen size determined to be 1920 x 1080
>>>[ 52763.039] (--) NVIDIA(0): DPI set to (30, 30); computed from
>>>"UseEdidDpi" X config
>>>[ 52763.039] (--) NVIDIA(0):     option
>>>[ 52763.039] (II) NVIDIA: Using 24576.00 MB of virtual memory for
>>>indirect memory
>>>[ 52763.039] (II) NVIDIA:     access.
>>>[ 52763.059] (II) NVIDIA(0): Setting mode "DFP-1:nvidia-auto-select"
>>>
>>>Other people with a 4K monitor must have discovered this issue, but my
>>>searching has only shown up some older issues fixed with modelines or
>>>insidious EDID fake files to force X not to ask for what's available.
>>>I've tried some of these with no success, but thought someone has had
>>>to have come across this before, so I'm humbly asking for help.
>>>
>>>I'm using an NVIDIAGeForce GT1030 card, NVIDIA driver 450.51.06, a
>>>Denon AVR-X2600H, and an LG OLED65C9PUA 4K HDR TV.
>>>
>>>Regards,
>>>
>>>Ken Emerson
>>
>>The standard fix is to use nvidia-settings to download the EDID data
>>for the TV, then set up xorg.conf to use the downloaded copy of the
>>EDID data and not to fetch the EDID data from the TV.  This seems to
>>be a problem that happens with AV amps more often than the TVs
>>themselves, so it may not happen if you directly connect the TV to the
>>MythTV box.  I would recommend having it directly connected when you
>>download its EDID data.
>>
>>It is likely that you would be able to use an xrandr command to get
>>the display to switch back to 4k mode again, if you preferred to do
>>that every time it happens rather than messing around with xorg.conf.
>
>Thank you. That worked.  For those who search for this problem with
>EDIDs and Audio/Video Receivers (AVR) I have included the link that
>I used to create the edid.bin file for my TV.  Plugging the TV directly
>into the video card is a key point.
>
>https://kodi.wiki/view/Archive:Creating_and_using_edid.bin_via_xorg.conf
>
>Regards,
>
>Ken Emerson

There is an easier way to get the EDID data than those on that page.
If you run nvidia-settings, it has an option to read the EDID data
from a device and store it directly to a file.