I am working on a LS1021a board, using NXP SDK 1.9.
At the moment, I am using the ls1021atwr_sdcard_ifc_config for u-boot, and I successfully boot on the board without secure boot enabled, having Linux on the Normal World and a Secure OS on the Secure World.
My goal is to activate the secure boot to verify that u-boot and (at least) the Secure OS are correctly signed.
When I build u-boot, I see there is a ls1021atwr_nor_SECURE_BOOT_config target which is build. My question are (sorry if some are depending on NDA, I'm not sure):
1) can I build a sdcard_SECURE_BOOT_config version of u-boot ?
2) should I use the nor_SECURE_BOOT_config to validate the sdcard_ifc_config I already have build ?
3) Disregarding the OS in the secure world and my modification to u-boot, is there some documentation on how to correctly use nor_SECURE_BOOT_config to enable secure boot on this board (with just Linux on top of u-boot) ?