I followed the installation instructions on the alarm wiki to the letter, intending to use my new ODROID-XU4 with a 16GB eMMC card.
However, booting in µSD mode using the eMMC card (using the eMMC-to-µSD adapter, with the XU4 switch set to "µSD") is unsuccessful (no fan spin-up, I don't have the serial connector so I'm not going to be able to get much extra info). Booting is of course also not possible from the eMMC when plugged directly into the eMMC (with the XU4 switch set to "eMMC"), since clearly the final bootloader stage was not yet completed.
To rule out the possibility of (total) board failure, I also decided to test using a real 64GB µSD card. I again followed the wiki instructions, inserted the µSD, set the switch to µSD, and turned on the power. The device boots perfectly fine (fan spins up, can connect via SSH).
This is where it gets interesting. I had left the eMMC card plugged into the eMMC port on the board, which can be seen with the output of `lsblk`. Pay close attention to the partition sizes, and the previously mentioned card sizes (64GB µSD, 16GB eMMC):
$this->bbcode_second_pass_code('', '[alarm@alarm ~]$ lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
mmcblk1 179:0 0 59.5G 0 disk
`-mmcblk1p1 179:1 0 59.5G 0 part
mmcblk0 179:16 0 14.7G 0 disk
`-mmcblk0p1 179:17 0 14.7G 0 part /
mmcblk0boot0 179:32 0 4M 1 disk
mmcblk0boot1 179:48 0 4M 1 disk
mmcblk0rpmb 179:64 0 4M 0 disk ')
It seems that despite "booting" from the µSD, I'm actually loading Arch itself from the eMMC slot. Out of curiosity I tried running the sd_fusing script from this session, giving it the eMMC device /dev/mmcblk0 but this had no effect (booting in "eMMC mode" still fails).
How might I further diagnose this? What further info (short of my purchasing the serial adapter) would be useful for me to provide?
I very much look forward to any input.