ayufan Ubuntu Mate 0.9.14 black screen boot on new Pinebook Pro

[EricL]

Hey all.

I found the onboard Manjaro on my new Pinebook Pro to be a bit limited (a lot of needed yet missing software), so I've been trying to get Ubuntu running.  I've actually had really good results with ayufan's Focal Fossa build (0.10.12), however after banging my head against a wall trying to get LUKS encrypted root going, I figured I'd try downgrading to Bionic and see if I can get it running with a little less "beta-ness".

However, after downloading and flashing the image for Bionic (0.9.14) to SD card, it boots to a black screen.  I can see the backlight for the flat panel light up, but nothing is ever displayed.  I even get the login prompt sound, so I know it did actually boot, but no amount of key-pressing seems to wake up the display.  I can't even get to a text console with CTRL+ALT+F2.

I'm wondering if something may have changed between the last production run of Pinebook Pro and this one (just got mine at the beginning of June, so it should be the latest batch), something preventing Bionic from properly initializing the flat panel.  I figured before I broke out the serial cable and tried to hack the thing into submission, I'd check to see if anyone else had a similar experience and figured out a workaround.  Kernel option, maybe?  Something I can stick in extlinux.conf long enough to get it to boot, run updates, and hopefully fix the problem properly?

Looking forward to hearing a few ideas.

Eric

[Syonyk]

Serial port is your best idea here. :/ The whole "The display doesn't work until an awful lot of stuff is loaded and working" thing makes early boot issue troubleshooting hard.

Though I think regardless of the distro, encrypted LUKS is going to be a challenge, because you're unlikely to have all the stuff required to bring up the display in your initrd without a lot of work. You'd probably be better off, sanity-wise, with an unencrypted root and an encrypted home directory.

[EricL]

Anyone happen to know what bitrate the serial console runs on for ayufan's Bionic Mate 0.9.14?  I can get all the U-Boot messages at a bitrate of 1500000 as mentioned in the pinebook wiki, but it seems the bitrate changes when the kernel kicks in.  I've tried a few standard ones (9600, 19200, 115200), but it just produces jibberish after the kernel loads. 

With regards to my reason for needing LUKS, I'll break that out into a new thread rather than hijacking this one.

[trinapicot]

I'm wondering if something may have changed between the last production run of Pinebook Pro and this one...

There are known problems booting some distribution images with manjaro installed to emmc. See here for a list and a possible workaround: https://gitlab.manjaro.org/snippets/490

Another workaround is to install uboot-pinebookpro-bsp and write the bsp uboot images to emmc.