nrfutil pkg generate with bootloader only generates unexpected and invalid package

[andreasd]

Hi,

I'm trying to generate a ZIP file for DFU update of the bootloader only. I'm using nrfutil 5.2.0 (but also tried the master branch of the github repository pc-nrfutil, it results in the same behavior).

nrfutil pkg generate  --bootloader Bootloader.ihex --hw-version 52 --key-file mykey.pem --sd-req 0xA5 --bootloader-version 5 out.zip

When I display the package:

$ nrfutil pkg display out.zip

DFU Package: <out.zip>:
|
|- Image count: 1
|
|- Image #0:
   |- Type: bootloader
   |- Image file: Bootloader.ihex
   |- Init packet file: Bootloader.ihex
      |
      |- op_code: INIT
      |- signature_type: ECDSA_P256_SHA256
      |- signature (little-endian): <sig>
      |
      |- fw_version: 0x00000005 (5)
      |- hw_version 0x00000034 (52)
      |- sd_req: 0xA5
      |- type: BOOTLOADER
      |- sd_size: 0
      |- bl_size: 35400
      |- app_size: 0
      |
      |- hash_type: SHA256
      |- hash (little-endian): <hash>
      |
      |- boot_validation_type: ['VALIDATE_GENERATED_CRC']
      |- boot_validation_signature (little-endian): ['']
      |
      |- is_debug: False

However, when I now manually unzip the ZIP file, there's a "ihex" file inside it. When I open it with a text editor, however, it's only 141 Byte big, and contains binary data (so no actual valid Intel HEX data).

Subsequently, an update with nrfutil dfu ble also fails (pc_ble_driver_py.exceptions.NordicSemiException: Response Code InvalidParameter). Segger RTT logging yield a "Trying to create an object with a size that is not page aligned".

The bootloader is the secure_ble_dfu example from the nRF SDK 14.2.0.

What's also surprising to me: When I generate a package with both softdevice and bootloader, the zip file contains a valid hex file and a ".dat" file with 153 bytes. It seems to be that that's what the bootloader.hex from the first package is supposed to be?

[andreasd]

Found the culprit: The problem is the file ending .ihex (which was used by the Toolchain/Makefile I was using to generate the project).

nrfutill doesn't seem to recognize this as a valid hex file and does strange things with it. Renaming the file to Bootloader.hex yields the expected result.

Still, would you consider this a bug in nrfutil that should be fixed?

[Amanda Hsieh]

Hi, 

According to the Creating a firmware package with nrfutil page:

You can add the following firmware images in binary or hexadecimal format to the zip file:

• --application image: an image of an application
• --bootloader image: an image of a bootloader
• --softdevice image: an image of a SoftDevice

However, Intel HEX is not recognized or supported by nrfutil. 

I would report to the development team. Thanks for the feedback.   

-Amanda H.

[andreasd]

Hi Amanda, thanks for the reply. What does the documentation mean by "hexadecimal format"? I'm pretty sure nrfutil works with what I think are Intel HEX files, as long as they have the file extension .hex.

[Amanda Hsieh]

Hi, 

It looks like a typo in the document.

Yes, you are right. What they mean is that you can either pass a *.bin or a *.hex file (in intelHex format). However, the nrfutil expects it to be .hex which is the output in all of our SDK examples.

-Amanda H.