FOTA update with external flash

[veli-pekka]

I am trying to set up FOTA support with external flash for mcuboot secondary partition. I have gone through several tickets on the subject, but haven't been able to solve the issue. 

The ncs version I am using is 2.9.1.

The problem seems to be (like in many other cases) secondary flash address etc. is not available:

26 | #define S_IMAGE_SECONDARY_PARTITION_OFFSET (PM_MCUBOOT_SECONDARY_ADDRESS)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/opt/nordic/ncs/v2.9.1/nrf/modules/trusted-firmware-m/tfm_boards/partition/region_defs.h:102:36: note: in expansion of macro 'S_IMAGE_SECONDARY_PARTITION_OFFSET'
102 | #define SECONDARY_PARTITION_START (S_IMAGE_SECONDARY_PARTITION_OFFSET)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/opt/nordic/ncs/v2.9.1/modules/tee/tf-m/trusted-firmware-m/platform/ext/target/nordic_nrf/common/core/target_cfg.c:763:33: note: in expansion of macro 'SECONDARY_PARTITION_START'
763 | .secondary_partition_base = SECONDARY_PARTITION_START,
| ^~~~~~~~~~~~~~~~~~~~~~~~~

I think the problem comes down to this:

warning: PM_EXTERNAL_FLASH_MCUBOOT_SECONDARY (defined at
/opt/nordic/ncs/v2.9.1/nrf/subsys/partition_manager/Kconfig:214) was assigned the value 'y' but got
the value 'n'. Check these unsatisfied dependencies: (PM_EXTERNAL_FLASH_ENABLED || MCUBOOT) (=n).
See http://docs.zephyrproject.org/latest/kconfig.html#CONFIG_PM_EXTERNAL_FLASH_MCUBOOT_SECONDARY
and/or look up PM_EXTERNAL_FLASH_MCUBOOT_SECONDARY in the menuconfig/guiconfig interface. The
Application Development Primer, Setting Configuration Values, and Kconfig - Tips and Best Practices
sections of the manual might be helpful too.

So, I may be missing some configuration parameters. Those two mentioned in the warning are not user settable. How would I be able to enable this?

[veli-pekka]

there is in build/mcuboot/zephyr/.config and .config.sysbuild

CONFIG_PM_EXTERNAL_FLASH_MCUBOOT_SECONDARY=y

Which makes that warning look quite strange.

[AHaug]

Hello,

There are a couple of items here that could be the root cause, but for a starter I think I might want to recommend you to have a look at https://academy.nordicsemi.com/courses/nrf-connect-sdk-intermediate/lessons/lesson-9-bootloaders-and-dfu-fota/ with focus on

• https://academy.nordicsemi.com/courses/nrf-connect-sdk-intermediate/lessons/lesson-9-bootloaders-and-dfu-fota/topic/dfu-for-the-nrf5340/ 
• https://academy.nordicsemi.com/courses/nrf-connect-sdk-intermediate/lessons/lesson-9-bootloaders-and-dfu-fota/topic/exercise-3-dfu-with-external-flash
• https://academy.nordicsemi.com/courses/nrf-connect-sdk-intermediate/lessons/lesson-9-bootloaders-and-dfu-fota/topic/exercise-5-fota-over-bluetooth-low-energy/  

There's also the aspect of using TF-M which might change some things w.r.t the samples provided as solutions to the exercises, but for now lets have a look at the external flash configuration as well as the BLE FOTA  configuration (if you're doing BLE Fota and not other types of FOTA).

Could you either go through the links provided and see if you spot any differences w.r.t configuration of your external flash DFU solution and/or share your implementation of the external flash FOTA (configs, board files, initialization of the qspi/spi driver etc)?

Kind regards,
Andreas