Keystone Bootable SD Card Issue with Freedom U740 Bootloader

Hello SiFive Community,

I’m currently working on creating a Keystone bootable SD card for my board, but I’ve encountered an issue related to the bootloader. I have been following the documentation for the HiFive Unleashed board (which uses the Freedom-U540 bootloader), but my target environment utilizes the Freedom-U740 bootloader. The differences between these two appear to be causing compatibility issues.

As we are new to Hifive Unmatched, a detailed guide or any advice on adapting the bootloader for the Freedom U740 would be very helpful. For reference, here are the relevant resources: