RE: The sample bootloader project resets with a bus fault

Simon — Wed, 17 Feb 2021 14:55:57 GMT

The secure bootloader is never used alone, so the default way to build it is to add it as a child image to your main application. That can be done by setting CONFIG_SECURE_BOOT=y in e.g. zephyr/samples/hello_world/prj.conf. If you build the hello world sample then, you can see the build output for the secure bootloader in \zephyr\samples\hello_world\<build folder>\b0. If you run west flash, it will flash the hex file zephyr\samples\hello_world\<build folder>\zephyr\merged.hex which contains both the hello_world sample as well as the secure bootloader.

I just tested this and it worked:

*** Booting Zephyr OS build v2.4.0-ncs2  ***
Attempting to boot slot 0.

Attempting to boot from address 0x8000.

Verifying signature against key 0.

Hash: 0xae...d1

Firmware signature verified.

Firmware version 1

Setting monotonic counter (version: 1, slot: 0)

Booting (0x8000).

*** Booting Zephyr OS build v2.4.0-ncs2  ***
Hello World! nrf52840dk_nrf52840

However, there might be circumstances where one would like to build the secure bootloader as a standalone. I can look into this if you would like to.

Best regards,

Simon