Oh, hello, i recognize your username from the jolla forums :-) I do have two Gigasets here (GX290 and GX4 pro) waiting to be flashed, but I still need to finally set up a windows machine to make a proper backup of the stock android images and generate the scatter files. Like with most of the SoC-Vendors, the MTK tools are quite a PITA. I have to download some weird binaries from some weird websites. How can it be that there are no official tools available for things like this?!

And there is one more Question I have since you're already here ;-) I'm already doing embedded Linux development in my day job, so I would say I have quite some knowledge in that area. However I haven't found a good introduction to this whole "porting" topic. Do you have some advice on how to get started in that direction? What exactly happens when I flash (say) sailfish onto some (specific) Android version? Why do I even need this? How does the whole libhybris thing work and why don't people just use the binary drivers from some Android image? It's all very confusing to me. Especially since people from the android corner seem to use different terminology that the embedded Linux crowd...

anyway, thanks for your work so far. I hope I can join the SFOS users (again) soon!

Ah, I just abandon the idea of recovery on these phones and use the ubports installer once. Thereafter, I just flash directly. I have done the MTK tools dance, but don't any longer. Sorry :(

Ah, I have to admit I don't know much about porting :) We did put up a community wiki and the HADK is up there: https://sailfishos.wiki/books/hadk/page/hadk so that you might get some idea of the process ... I'm not sure to what extent this is different from that 'halium' builds that piggz makes. It makes sense to ask him directly, since he has a stream lined process that targets, among others, the phones you have.

As to why the hardware adaption layer is needed (ie. the android one) it's where all the binary blobs are :) Among other bits.