MCUBoot "reading sectors failed" problem with nrf-sdk v1.6.0

[n.marty]

Hi all

We are switching to nrf-sdk v1.6.0 in our project and encountered a problem with MCUBoot.

The image builds successfully and can be flashed successfully as well. MCUBoot loads but is then unable to find a bootable image. There's a message which says:

W: Failed reading sectors; BOOT_MAX_IMG_SECTORS=128 - too small?

I tried increasing BOOT_MAX_IMG_SECTORS up to 91216. But there's still the same error message. I can't increase it more otherwise it overlaps SRAM region. I think the problem is somewhere else but I don't know where. Can someone give me a hint where to look for the problem?

I read that BOOT_MAX_IMG_SECTORS configuration is important for swapping the image in the secondary slot to the primary slot after an update.
I thought as a workaround I could configure MCUBoot to work in XIP Mode "execute in place", which does not need swapping and thus my initial problems disappears. Does anyone have a recommendation if it is a good idea to use XIP?

best regards

[n.marty]

Hi all

I found a hotfix for the problem which was actually a problem with the build configuration.

When applying my own mcuboot.conf to the mcuboot project (via cmake) like this
list(APPEND mcuboot_OVERLAY_CONFIG ${MY_MCUBOOT_CONF_FILE})

it is dropping the partition manager configuration "partition_manager_enabled.conf" for some reason which in my eyes is a bug.

My hotfix for the moment is to manually append the partition_manager config in addition to my "usual" mcuboot.conf. I do it now like this:
list(APPEND mcuboot_OVERLAY_CONFIG ${MY_MCUBOOT_CONF_FILE})
list(APPEND mcuboot_OVERLAY_CONFIG "/opt/zephyrproject/nrf/subsys/partition_manager/partition_manager_enabled.conf")

and it builds a working bootloader.

I would rather not deal with such a static, absolute path in my project because this is gonna break sooner or later again.

What is the best practice to build MCUBoot with own configuration flags?

best regards