DFU target API integration

[Jithin A]

Hi,

I am trying to integrate DFU into my application. Below is what I need to do.

I receive OTA application image over BLE (I can not use legacy DFU feature as we are using our own encryption for all the data exchange over BLE) and I need to write the application image.

I try using dfu_target APIs to do the work and I see undefined reference error for all the dfu_target APIs.

Please let me know what I need to do to include dfu_target APIs into my application.

Thank you in advance.

[Sigurd Hellesvik]

Hi,

See DFU target target library.

Our nRF9160: Full modem firmware update using SMP Server sample uses the dfu_target library, so you can get some inspiration from that as well.

Regards,
Sigurd Hellesvik

[Jithin A]

Hi Sigurd,

Thank you for your response

I am also referring the same library for integration but I do not see any details on how to enable the target library in any application.

Let me share my config so that you can point me if I am missing anything.

I included the below header file:

#include <dfu/dfu_target.h>

I also added below config in my prj.conf file

CONFIG_DFU_TARGET=y

CONFIG_DFU_TARGET_MCUBOOT=y

Still I see below error:

undefined reference to `dfu_target_done'
undefined reference to `dfu_target_offset_get'
undefined reference to `dfu_target_schedule_update'
undefined reference to `dfu_target_write'

 

[Sigurd Hellesvik]

Hi,

"undefined reference" errors are usually due to either of two things:

1. Missing Kconfig option (CONFIG_*)
2. Missing #include

If the include was wrong, it would give a build error.

Ïf the Kconfig option is not set, it will give a warning in the build.
There are some warnings for this in your build, so I guess that this is the reason for the "undefined references".

To figure out why the Kconfig option is not set, either:

1. Read the warning
2. Use the VS Code "Kconfig" action.
   1. Search for the Kconfig option in question
   2. Click the "information" symbol
   3. See Kconfig dependencies in the lower right corner

Regards,
Sigurd Hellesvik

[Jithin A]

Hi Sigurd,

FYI,

We have non-secure and TF-M images in our application.

I found that if we add DFU into the non-secure application image it is building successfully.

If we integrate it to the TF-M application I see the above mentioned error. 

As I said earlier we have our own encryption which is performed inside TF-M so I can not decrypt the data in non-secure and the reason why I can not use DFU in non-secure.

Please let me know what I need to do to enable DFU in TF-M application image.

One more thing I see signed .hex file is created for DFU and this can not be used for writing into the secondary slot directly please refer me to the respective signed bin file which can be used for writing into the secondary slot and update on the boot.

Please guide me through this as this is blocking our development process in remote as we can not perform OTA for FW update.

[Jithin A]

Hi Sigurd,

Any update on this.

Please help me with this ASAP. 

Thank you in advance.

[Sigurd Hellesvik]

Hi,

I will look into your query and return on Monday with more information

Regards,
Sigurd Hellesvik

[Jithin A]

Hi Sigurd,

For the time being I try to process the DFU in non-secure and I see error -19 every time I call dfu_target_init()

dfu_status = dfu_target_init(DFU_TARGET_IMAGE_TYPE_MCUBOOT, -1, file_size, dfu_callback_function);

Below is my prj.conf

# Enable DFU target for application image
CONFIG_DFU_TARGET=y
CONFIG_IMG_MANAGER=y
CONFIG_STREAM_FLASH=y
CONFIG_STREAM_FLASH_ERASE=y
CONFIG_DFU_TARGET_STREAM=y
CONFIG_DFU_TARGET_MCUBOOT=y

Am I missing any configuration here?

Now I am referring DFU target document to implement the same. Please share if any other documentation I can refer to.

[Sigurd Hellesvik]

Hi,

I found https://github.com/nrfconnect/sdk-nrf/tree/main/tests/subsys/dfu/dfu_target/mcuboot and try to build this for nrf5340dk_nrf5340_cpuapp_ns.

This seems to init fine.
Some errors are reported with cleaning up, but can you have a look at this test, and see if it matches what you do?

Also:

Jithin A said:

I try to process the DFU in non-secure

Does this work in secure?

Regards,
Sigurd Hellesvik

[Jithin A]

Does this work in secure?

No, if I integrate dfu_target functions inside secure I am getting the below mentioned errors

undefined reference to `dfu_target_done'
undefined reference to `dfu_target_offset_get'
undefined reference to `dfu_target_schedule_update'
undefined reference to `dfu_target_write'

[Jithin A]

Also I see there are many output build images and I want to know which output build image is suitable for DFU over BLE. (NOTE: I have 2 images in my application non-secure and TF-M images).

I need to update both the images over DFU. I am confused which build image to write in the secondary slot so the MCUBoot can update both non-secure and secure in the next boot.

Thanks in advance.

[Sigurd Hellesvik]

Jithin A said:

functions inside secure

Can you specify what you mean by "inside secure", either of the following?

1. Build for nrf5340dk_nrf5340_cpuapp
2. Build for nrf5340dk_nrf5340_cpuapp_ns, but manually call functions from secure side

Jithin A said:

Also I see there are many output build images and I want to know which output build image is suitable for DFU over BLE. (NOTE: I have 2 images in my application non-secure and TF-M images).

I need to update both the images over DFU. I am confused which build image to write in the secondary slot so the MCUBoot can update both non-secure and secure in the next boot.

In the nRF Connect SDK, the dfu_application.zip is used when updating both cores simultaneously over Bluetooth Low Energy.
For an example see Simultaneous DFU for app and net core of nRF5340.

Regards,
Sigurd Hellesvik

[Jithin A]

Sigurd Hellesvik said:

In the nRF Connect SDK, the dfu_application.zip is used when updating both cores simultaneously over Bluetooth Low Energy.

Actually I need bin file.

The file will be transmitted over BLE from the App and my device will write the bin into secondary slot which is allotted ~400kb. 

No need of updating net core every time.

Please guide me to the respective file.