I was really hoping that like the Duo, this just worked out the box. Alas, I was wrong.
It took me a hot minute, and using the CP2104 link on the debug pins to see what was going on, but eventually I found that the SBI configuration on the SPI flash appeared corrupt, and thus it could not boot to SD and defaulted to eMMC (mmcblk0).
Eventually I got it booting by flashing both an eMMC module, and SD card, and it would then load the Linux kernel from eMMC, which would then load the userspace etc from SD. Following this I quickly updated extlinux.conf to boot from just eMMC.
Following all this, since there are no official eMMC images out at the time of writing, I decided to cut my own. I also took this opportunity to add vim, screen and ifconfig, along with setting it up to auto-expand on first boot. Here’s my images;
Let me know in the video comments if you have any other improvement ideas! (No, I am not enabling swap hah).