RPI4 - does not obey config.txt set resolution

1st Official Post

    Hi all,

    I have been using rpi3b with these options for a while on my SDTV and it worked beautifully.

    Tried to update to rpi4 - no luck. It displays correct resolution for rainbow boot screen but librelec forces 1920x1080@60hz for some reason.

    I've attached config.txt (form rpi4, but I tried the same with latest libreelec on rpi3b and it works fine)

    Is librelec overriding edid or something? Any help is appreciated.

    These are my custom options

    hdmi_ignore_cec=1

    hdmi_drive=1

    hdmi_force_hotplug=1

    hdmi_ignore_hotplug=0

    hdmi_ignore_edid=0xa5000080

    hdmi_group=1

    # 320x240 - works rpi3

    # hdmi_mode=9

    # 576i - works rpi3

    # hdmi_mode=22

    # 576i quad - works rpi3

    hdmi_mode=26

    # 576i 100hz

    # hdmi_mode=45

    # 576i 200hz

    # hdmi_mode=55

    # 1080i

    # hdmi_mode=39

    disable_overscan=1

    framebuffer_priority=2

    hdmi_force_mode=1

    hdmi_blanking=1

    hdmi_pixel_encoding=1

    hdmi_ignore_edid_audio=1

    config_hdmi_bo*ost=6

    sdtv_mode=2

    sdtv_aspect=3

    Thanks!

    Well, this is the image I've been using:

    LibreELEC-RPi4.arm-9.2.7.img

    So it was 9.2.7 all the time...

    Also tried now

    video=HDMI-A-1:320x240@60

    and even that does not show correctly.

    On rpi 3b it all works fine....

    No luck, same problem - libreelec ignores it and turns on to 1920x1080@60, it does not have the pal resolution in its list, just standard hdmi resolutions

    I changed it to 640x480 but its still out of sync, since its 480p60

    These are tvservice outputs

    LibreELECcrt:~ # tvservice -s

    state 0xa [HDMI CUSTOM RGB full 4:3], 640x480 @ 60.00Hz, progressive

    LibreELECcrt:~ # tvservice -l

    1 attached device(s), display ID's are :

    Display Number 2, type HDMI 0

    This command switched to the correct mode (720x576i), but kodi is mishapen and it reverts to its standard resolution after restart...

    LibreELECcrt:~ # tvservice -e CEA\ 26

    Powering on HDMI with explicit settings (CEA mode 26)

    Same,

    I would say its booting now in 4:3 (rainbow screen) as before it would boot in 16:9

    but Kodi still 480p so its garbled...

    It looks like libreelec is loading standard HDMI edid or something, kodi available resolutions are from 480p to 1080p 60

    And again same.

    But i got more info,

    If i disable dtoverlay in distroconfig boot logo of libreekec looks perfect, but libreekec wont start ;)

    It seems that vc4-fkms-v3d is messing with resolution somehow

    Hi Milika, could you test this guide?

    Post

    RE: LibreELEC-RR [ Brave | Spotify | Moonlight | Emulationstation | Retroarch | Pegasus ]

    […]

    Hope it helps!

    1) In command line; first remount the /flash boot partition as read-write:

    (Code, 1 line)

    2) Then use nano to edit the distroconfig.txt:

    (Code, 1 line)

    3) Comment the line disable_fw_kms_setup=1, (This prevents to pick a mode from the EDID info coming from the HDMI) , should be the last line, number 8:

    (Code, 1 line)

    (Ctrl + o to save the file - Ctrl + x to exit nano)

    4) Then use nano again to edit the config.txt:

    (Code, 1 line)

    5) At the end/bottom of the file add the hdmi mode…
    ElBoluTony
    March 26, 2021 at 9:29 PM
    • Official Post

    The last thing I would try on config.txt (post #6, #8 and #12) is to add hdmi_force_mode=1.

    If that doesn't work, quit the config.txt approach, and put the working tvservice line (post #7) into /storage/.config/autostart.sh.

    You can also test LE 10.0 Beta official or nightly, but I'm not familiar with the HDMI mode syntax of cmdline.txt.

    Quote from milika

    No luck, its like kms driver has its own logic - ignoring all setup before

    Hi! Sorry for the delay, i've just swapped the distro (was using LibreELEC-RR) on a new micro-SD, now i'm on nightly, just tested the previous guide and worked on 640*480 on a 4K TV. (Group 1 - Mode 1).

    Be sure to comment the line disable_fw_kms_setup=1, or change it to 0 "disable_fw_kms_setup=0"! on flash/distroconfig.txt

    Bye.