IMX6ULL SD card flashing using UUU

[devika_ramesh]

Hi

I am using custom based IMX6ULL processor. Image is flashed using uuu tool.What I observe is if the sd card with a bootable image is inserted into the board , even if the boot mode switch is in serial download mode, the board is booting up. Is there any configuration change that has to be made in order to stop booting from sd card while in serial mode even if the sd card is inserted?

[AldoG]

Hello,

If using uSDHC1 the device it is failing into SD/MMC manufacture mode, you may disable this in the boot eFuses DISABLE_SDMMC_MFG, from reference manual:
 

When the internal boot and recover boot (if enabled) failed, the SDMMC_MFG_DISABLE fuse bit isn't set and the EEPROM recovery fuse bit is set, the boot goes to the SD/MMC manufacture mode before the serial download mode.

In the manufacture mode, one bit bus width is used despite of the fuse setting. In the manufacture mode, the SD or MMC card will be scanned on the uSDHC1. If a card is detected and a valid boot image is found in the card, the boot image is loaded and executed. Pad of SD1_CD is used to detect whether a card is inserted or not.

By default, the SD/MMC manufacture mode is enabled. Blow the fuse of the DISABLE_SDMMC_MFG to disable it.

Another way to do this, try powering up your custom board and then insert your SD card this will ensure that the device goes into serial downloader.

If the above is not possible inserting a "clean" SD card may be an option.

Hope this helps,

Best regards,

Aldo.