Kontron KTAM3874-pITX - Manual (Page 278)

KTD-S0057-I Page 274 Appendix A: Linux® on microSDTM Card
KTAM3874/pITX Software Guide
The easiest way to prepare the microSD
TM card is to use one partition. The user space really needs an Ext-
format; therefore only Ext2 to Ext4 are possible.
ATTENTION
Do not use the Ext4 format because U-Boot
cannot boot the Kernel from an Ext4 partition.
After partitioning the microSD
TM card requires formatting.