I've been investigating the problem a bit more:|
a.) if I boot from emmc and then insert an SD card, I get the following result
i.) if the card has a single partition on it, regardless of the size of the card, the Hikey can read it, and /dev is populated with mmcblk1 and mmcblk1p1;
ii.) if the card has two partitions on it, one fat16 the other ext4, regardless of whether the partition table is MBR or GPT, the Hikey cannot read the card, /dev is populated solely with mmblk1 and no partitions are indicated; gdisk /dev/mmcblk1 leads to a hang in the system;
iii.) if the card contains an unaltered image from the 96boards site, then the system sees the two partitions.
Something seems to be wrong at a low level with the SD card reader driver.