STM32U585 SBSFU - Can't invoke external loader in production mode

[horatiosdad]

 

After porting the application "STM32Cube_FW_U5_V1.8.0\Projects\B-U585I-IOT02A\Applications\SBSFU" to our own board we have everything operational apart from the ability to invoke the local loader in production mode (RDP2).

I have reverted to the original B-U585I-IOT02A board and project and have a similar issue so I am wondering if this is broken or we have misunderstood something. The loader can be invoked in TFM_DEV_MODE with RDP0 but not in production mode with RDP2. The SBSFU application runs fine.

Changes from the default STM SBSFU project settings we used to test this on B-U585I-IOT02A

1) In SBSFU_Boot project remove the TFM_DEV_MODE pre-processor symbol definition

2) In boot_hal_cfg.h >> #define TFM_TAMPER_ENABLE NO_TAMPER

3) In boot_hal_cfg.h >> #define #define TFM_OB_BOOT_LOCK 0

4) In flash_layout.h >> //#define MCUBOOT_PRIMARY_ONLY (definition commented out)

5) In flash_layout.h >> #define MCUBOOT_APP_IMAGE_NUMBER 2

6) In hardening.sh >> write_protect_secure="-ob...........BOOT_LOCK=0"

 

Any ideas?

Thanks in advance