[RPi5] No Display After Reboot

    I've done a clean install on my RPI5. It works great in terms of installing addons, setting up wireguard, and watching programs. However when I either reboot the Pi or I turn the TV off, the Pi no longer outputs an HMDI signal. I can log in remotely and head /sys/class/drm/*/status shows me the HDMI is connected however there is no signal, as reported by the TV. I've tried systemctl restart kodi and getedid create but they don't help, I've tried different TVs, different HDMI cables, and plugging into the other HDMI port on the Pi but nothing helps.


    Andy advice?

    Quote from slim0287

    I've done a clean install on my RPI5. It works great in terms of installing addons, setting up wireguard, and watching programs. However when I either reboot the Pi or I turn the TV off, the Pi no longer outputs an HMDI signal. I can log in remotely and head /sys/class/drm/*/status shows me the HDMI is connected however there is no signal, as reported by the TV. I've tried systemctl restart kodi and getedid create but they don't help, I've tried different TVs, different HDMI cables, and plugging into the other HDMI port on the Pi but nothing helps.


    Andy advice?

    Try the force hotplug option.

    Oh thanks for the reference. I had forgotten to write earlier that I tried force hotplug but I was using config,txt and did not know it had moved to cmdline.txt since LE10.


    I'm now having all kinds of problems getting that Pi5 to display no matter what OS I put on it. The machine does boot up and I can SSH into it, but whether it is libreelec, Raspberry Pi OS, or dietpi, I get no display. I'll work to get this sorted out so I can try your suggestion.

    Please provide a full debug log.

    How to post a log (wiki)

    1. Enable debugging in Settings>System Settings>Logging
    2. Restart Kodi
    3. Replicate the problem
    4. Generate a log URL (do not post/upload logs to the forum)

    use "Settings > LibreELEC > System > Paste system logs" or run "pastekodi" over SSH, then post the URL link

    I have another Pi5 that I am using and is currently working per your suggestions.

    In the interests of helping the community, I'll try again with the original Pi5 that is experiencing the display issues and produce the log you are asking for. However, I have no display output so I cannot use the GUI as you suggest in step 1 for enabling the debug log mode. I'll go through the wiki and look for a command line approach for enabling the debug log mode. This may take me a few days because I have some other projects around the house to get to plus I'd like to have some fun this weekend.

    This appears to be the same issue I've experienced with my RPi5 as well. A reboot and no signal at HDMI. I suspect it's more of a TV brand/age HDMI issue than the RPi5 but curious to see what he comes up with.

    My problem was that HDMI0 stopped working. It was flaky at first and often required a reboot to get a display output. Then it simply stopped working. I switched to HDMI1 and now have video output. I swapped between Raspberry PI OS and LibreELEC a few times during the diagnosis of this, as well as adding vc4.force_hotplug=1 and sometimes video=HDMI-A-1:4096x2160@60D to my cmdline.txt (neither cmdline.txt modifications were important). I admit I ought to have tried swapping ports sooner but cie la vie!


    I handle the hardware carefully so I am surprised I had this problem. I've had perhaps ten or so Pis over the years and don't recall having the hardware fail on me. This Pi5 clearly isn't very old so the hardware issue is disappointing.


    Thanks for the advice Da Flex , I appreciate your help.

    I have used two TVs. One is an LG OLED77CXAUA and the second is a Westinghouse WR43UX4210. Both TVs now work with HDMI1 and neither work with HDMI0 on this specific Pi5. On a second Pi5 that I own, both HDMI ports worth with both TVs.

    I had no idea the order in which devices were powered might be an issue. If I understand correctly the RPi5 system will record all necessary EDID info on it's 1st run and save in a permanent file for future boots?

    Quote from Reddirt

    I had no idea the order in which devices were powered might be an issue. If I understand correctly the RPi5 system will record all necessary EDID info on it's 1st run and save in a permanent file for future boots?

    No, it‘s not saved automatically. The command „getedit create“ is the manual process for that, and „getedit delete“ the counterpart.

    Explanation:

    Since some LE versions, its more important that:

    1. the EDID informations are available
    2. the EDID information must be correct

    Normally the HDMI handshake should be initialized during boot of the RPi. This happens dynamically with every boot process. At this time it‘s important that the HDMI chain is working and not disturbed. Disturbing is possible with bad manufactured/not certified HDMI cables, Micro-HDMI adapter, other HDMI devices …


    For example you should ensure, that you switch on the RPi as the last one if your cabling looks like this:
    RPi5 -> AVR -> TV

    The ideal sequential order to power-on is that:

    1. TV (provides EDID data for screen size/frequencies + supported sound channels/formats)
    2. AVR (passthrough and/or provides additional EDID data)
    3. RPi5


    If the AVR is powered-off, the RPi5 can‘t get the EDID information. Some newer AVRs are able to passthrough the EDID information if they are in standby. But there also exists TV, that only provide this information if the TV is switched on.

    To get a more robust system against the different power-on scenarios, it‘s possible to grab the EDID data one-time and save it in to the file system with the „getedit create“ command. After that the kernel/KODI will use this saved information at the next boot instead of the dynamical available EDID information. But this implies, that this file must match to your current hardware constellation. On this way it also possible to fake some information, if the extracted EDID block is incomplete or something like that.
    If you afterwards make some (conflicting to the EDID file) changes on your hardware/device firmware, then you must update or delete the EDID file again.

    Edited 5 times, last by HarryH (April 22, 2024 at 1:02 PM).

    Thanks for the detailed explanation. That explains why we sometimes have issues with HDMI connected devices. Also good to know I could create a file to work around the auto config although I understand why it's done this way. :thumbup:

    I used ssh and followed the link from DaFlex to create an EDID file. 1st time ever I rebooted my RPI5 on our old Sony with no issues whatsoever. You're the man D and thanks. Also kudos to Harry for a quick education on the how and why of EDID. Since this old Sony is the only TV with a RPI5 issue it's likely an aged TV firmware issue and nothing to do with LE.

    OK, I am sorry it took some time to get back to this issue. My Pi5, in fact the new one I referenced earlier, now has a similar problem: When I switch to a different HMDI input on the TV, after some time when I switch back the display is no longer present. I need to reboot the Pi5 through ssh to get it back.

    I've already taken the steps outlined above,forced hotplug in cmdline.txt and created a new EDID file. But I have the same problem-- after a reboot it works fine, but when I switch to a different HDMI port and then switch back after some time (my most recent test was a 5 minute delay), there is no longer a display and I need to reboot.

    I followed Da Flex instructions and created a log through ssh:

    https://paste.libreelec.tv/true-malamute.log


    Any help is appreciated.

    vc4.force_hotplug is incompatible with 4kp60 which you are using as GUI resolution so this is expected.

    I recommend setting the GUI resolution to 1920x1080 and setting up the whitelist as described in the wiki https://wiki.libreelec.tv/configuration/4k-hdr

    Also please drop vc4.force_hotplug from cmdline.txt and make sure you use a proper cable/connection which signals hotplug properly as otherwise you'll have the same issue whenever switching inputs or TV on/off while the RPi switched to 4kp60 during video playback.

    so long,

    Hias