On i.MX6UL EVK board,
it supports many boot device: SD Card(SD1) boot in main board,
micro-SD card(SD2) boot in CPU board and others....
I can boot SD1 and SD2 on the i.MX6UL EVK.
And mfgtool2 can download u-boot/kernel to SD2.
But mfgtool2 can't download u-boot/kernel to SD1.
I use mfgtool with script "mfgtool2-yocto-mx-evk-sdcard-sd2.vbs" for SD2.
And use mfgtool with script "mfgtool2-yocto-mx-evk-sdcard-sd1.vbs" for SD1.
I place SD-Card to SD1 slot on the EVK main board,then plug-in USB-OTG port.
mfrtool always display"no device connected".
(I done hardware modification---R613 (10K) must be removed
and R642 (10K) must be installed for SD1)