nRF5340: Forbid BT-DFU when only app_update.bin is uploaded

[ChriglSEI]

Hi there

My costumer was not able to update the cpunet on a nRF5340.

A lot of troubleshooting now led to the insight, that the costumer used only the app_update.bin file and not the complete .zip folder.

Is there a way to forbid the update on the nRF5340 when the net_core_app_update.bin is missing (so when the app is not using the .zip-folder)?

SDK: v2.6.1

Thank you and best regards

Chris

[Einar Thorsrud]

Hi Chris,

One way to solve this is to always use the same verion for compatible network and application core images, and build with CONFIG_NRF53_ENFORCE_IMAGE_VERSION_EQUALITY=y.

[ChriglSEI]

Is it correct, that CONFIG_NRF53_ENFORCE_IMAGE_VERSION_EQUALITY=y is set in the main prj.conf and not in child_image/mcuboot/prj.conf ?

[Einar Thorsrud]

Hi,

Sorry, I should have specirfied that. The config applies to MCUboot, so you can put it in child_image/mcuboot/prj.conf.

[ChriglSEI]

Hi Einar

Thank you for your response.

When I put CONFIG_NRF53_ENFORCE_IMAGE_VERSION_EQUALITY=y in child_image/mcuboot/prj.conf, it says that CONFIG_NRF53_UPGRADE_NETWORK_CORE=y is missing:

But when I put CONFIG_NRF53_UPGRADE_NETWORK_CORE=y also in child_image/mcuboot/prj.conf, it says that further depedencies are missing:

If I look into the build/mcuboot/zepyhr/.config:

CONFIG_SOC_NRF5340_CPUAPP=y but CONFIG_BOOTLOADER_MCUBOOT is not present

And here https://academy.nordicsemi.com/courses/nrf-connect-sdk-intermediate/lessons/lesson-8-bootloaders-and-dfu-fota/topic/exercise-3-fota-over-bluetooth-low-energy/ in Step 6.4 it says that CONFIG_NRF53_UPGRADE_NETWORK_CORE=y goes into the main prj.conf

Can you help?

[Einar Thorsrud]

Hi,

I have not been able to reproduce this on my end. However, I see it if I add CONFIG_NRF53_ENFORCE_IMAGE_VERSION_EQUALITY=y to the application configuration, where is should not be used. Can you make sure you only set CONFIG_NRF53_ENFORCE_IMAGE_VERSION_EQUALITY=y in the configuration for MCUboot?