Raspberry 4, Libreelec 10.0.1, no picture after reboot

  • Hello,

    I have yesterday Libreelec 10.0.1 cpl. reinstalled. Have previously had Libreelec 9.8.2 (I still have on separate card). I have with the new version problems with the image. It happens again and again that I get no picture after a reboot. Only after I disconnect the RPi from the power it works again. Sometimes not even then. The RPi is connected to an Onkyo receiver and from there it goes either to the TV or the beamer. Even when switching the AV receiver from TV to beamer or vice versa, I often get no picture. Only after I then completely restart it works again. Before with the 9.8.2 everything no problem. I have already tested various settings that I have found here or in other forums, unfortunately without success. Does anyone have an idea?

    Thanks a lot

  • I have returned to using a Rasp Pi 4b and a the latest nightly build on LibreElec connected to my Sony 4K TV, directly. 60Hz refresh rate is not used.

    I do not know how the non-nightly version would work.

    As per OP now and again I do get a blank screen on trying to boot the PI. The TV is already on and turned to the right HDMI connection. I do get the square coloured screen of the Pi initiating and then blank, only now and again. When I do get a Kodi screen all is well.

    when it next does this I will try and SSH into it. I can SSH to it when it boots fine, I use that to update to the latest nightly.

    If you could tell me, can't seem to find it by searching, how to retrieve the dmseg file, assuming I could do this from SSH and if it works with a blank screen.....Would it be....

    Open Terminal and type....... dmesg | Paste

    and then return the URL that is provided..?

    Not that it might matter but I have briefly tested OSMC before I used the nightly Libreelec, and that seemed fine. But only several boots were done when testing that, using their full release and not the test one.

  • Not sure why I don't get an email notification of a reply but.....

    Ok I added the above the the update folder. The first issue, before it updated, is that the re-boot function isn't great. That often results in the Pi rebooting, coloured square screen showing, and then a black blank screen. No SSH is possible at that stage.

    Powered off and on a couple of times and then it booted, and updated to the latest version as linked. Powered off for a while and then a blank screen after the initial coloured square splash. SSH shows this at this stage....Photo attached.

    Video showing the attempted boot....

    Video showing the failed boot.

  • Please test again with a clean installation of the latest nightly image.

    One of the video driver bugs caused the system to hang for a while, update/reboot in general works but could take several (3-10) minutes. If you pulled the plug in the middle of an update you may have messed up the installation.

    so long,

    Hias

  • Thanks for what you have written, it might have had some clues to help me.

    Rather than think that something is an issue, just because I see that message about there being no signal, I wait and it seems that it does boot to the Kodi desktop. Albeit sometimes it takes a while.....

    Link to my dmesg output

    I am now not thinking that there is a blank screen issue, in the same sense, just a delay that I was not allowing for during some boots.

    BTW even tho I am subbed to this thread I do not get updated reminders by email.

    Edited once, last by Vimes (January 16, 2022 at 4:55 PM).

  • Vimes thanks for the log!

    Can you add drm.debug=0x04 to the end of /flash/cmdline.txt (after "quiet", on the same line), reboot, then ssh in and run "pastekodi"? That should give some more info which might be helpful to debug the issue.

    so long,

    Hias

  • HiassofT You are welcome.

    Took a few times before it would occur after adding that line. It does seem to have a very long pause on some boots, rather than not boot.

    Here is that file....

    PasteKodi contents

    the above was taken from the boot of Libreelec after it started from that long delay, via SSH.


    BTW how many posts would it be before I get to post directly to the forum without the need of moderation.?

    Edited once, last by Vimes (January 16, 2022 at 7:10 PM).

  • Vimes thanks again for the logs! I've pinged RPi devs, there still seems to be a bug in the video driver (which causes the long delays, too).

    As your TV seems to support 4kp60, too, could you test if adding "hdmi_enable_4kp60=1" to /flash/config.txt helps?

    And, out of curiosity, how often do you run into that issue? I'm testing here with 4kp60 enabled and haven't seen it yet, but then I didn't try rebooting a large number of times so might have missed it.

    so long,

    Hias

  • HiassofT Hopefully it might help to resolve that bug, thanks for pinging them.

    I added that line and then rebooted. I don't think that it might have added that refresh rate as I see this....

    See file "limited refresh rate available"

    and also I ensured that the HDMI port is set to FULL range. The cable is ok for 60Hz and 4k.

    I have whitelisted all available 4k modes, but 60Hz is not there.

    I have seen an odd post or two where such issues of attaining 60Hz at 4k seems to happen, not sure if that is something I could resolve..?

    As for how often............At times it seems to be pretty regular, say one in three boots. That is a power off at the system from within Kodi, wait until only a red light on the Pi and then use the power off toggle switch within the USB-C cable. Then leave for twenty seconds or so and then power on.

    At other times I can do several of those cycles and it seems fine with no issues.

    I do know that if watching Amazon or Netflix I get both Dolby Vision and HDR fine, as their logos and video info of what is playing states that is streaming.

    Do you wish me to keep the drm.debug=0x04 there within that other file...?

    Delay still occurring as my posts are needed to be moderated before they can be viewed.

    just seen your other post and so added that line, it now reads....

  • HiassofT FYI......

    These photos are with an Amazon Fire TV Cube using the 19.3 version of Kodi and a bog std HDMI cable....

    So I do know that the TV is capable of running at 4k with a 60Hz refresh rate and Kodi, using the hardware in the Cube.

    Just for information purposes.

    Thanks :)

  • Please test again with a clean installation of the latest nightly image.

    One of the video driver bugs caused the system to hang for a while, update/reboot in general works but could take several (3-10) minutes. If you pulled the plug in the middle of an update you may have messed up the installation.

    so long,

    Hias

    Where can I get the "nightly image" for libreelec 10.0.1?

  • Vimes Check if you enabled "ultra hdmi deep color" in your TV's HDMI port settings. Also check the TV manual if the HDMI port supports 4kp60 at RGB 4:4:4 or YUV (or YCbCr) 4:4:4 - some TVs only support that on specific HDMI ports.

    If deep color is not enabled only YUV 4:2:0 is available at 4kp50/60, which the RPi4 doesn't support (but very likely your Fire TV).

    Using a 4kp60 mode isn't too important for this test, hdmi_enable_4kp60 will bump internal clock frequencies in the RPi a bit (which may help) and it's best to use 1080p60 as kodi GUI resolution, too.

    so long,

    Hias