Has anyone successfully built an Ubuntu Core image for the Variscite DART-6UL? It uses an i.MX-6UL processor, so I’d thought it might not be too hard to get going based on @ogra’s guide at https://ograblog.wordpress.com/2017/06/13/patching-u-boot-for-use-in-an-ubuntu-core-gadget-snap/ - but I’m having some real problems.
Firstly, Variscite have their own fork of u-boot and it seems like they haven’t merged back into the denix.de upstream for a while. I tried making changes to use FAT instead of MMC for the config, and eventually found I needed to use an older 2015 version of u-boot to be able to make the changes in the config and have them compile.
For reference, this is where I’m up to with the gadget snap config:
I’ve also got a kernel snap that I’ve compiled, and I have been able to confirm the kernel build does work - by taking the
zImage produced by
snapcraft and replacing a working Debian image’s copy with my snapcraft
zImage - I believe the kernel snap doesn’t actually use the zImage file, but I take this as confirmation at least that it does work enough to boot because Debian can boot using default Variscite settings and my zImage.
After running through the various
snapcraft commands, and making an image with
ubuntu-image, and flashing that onto an SD card, I do get some level of boot progress (see attached boot log) - but it crashes not to far in with a kernel panic. Just before that, I can see:
sdhci: Secure Digital Host Controller Interface driver sdhci: Copyright(c) Pierre Ossman sdhci-pltfm: SDHCI platform and OF driver helper sdhci-esdhc-imx 2190000.usdhc: Got CD GPIO mmc0: SDHCI controller on 2190000.usdhc [2190000.usdhc] using ADMA mmc0: host does not support reading read-only switch, assuming write-enable mmc1: SDHCI controller on 2194000.usdhc [2194000.usdhc] using ADMA Unhandled fault: external abort on non-linefetch (0x1008) at 0xa4a80fd4
Does this sound familiar to anyone? What should I be trying next? I’d been able to keep working away and get from zero output at all from my compiled u-boot, to getting to this point where it looks like it’s almost there - but there’s probably something small that I’ve missed.