how to verify after writing to external FLASH memory during full modem update (FOTA).

[Praveen Deshmane]

Hi Nordic Team,

I am using external flash memory which is of 8MB for full modem fota update.
HTTP full modem

I am able to update the modem using http full modem. 

I would like to know, how to verify that the downloaded full modem update file (.cbor file) is in external flash memory during FOTA. 

My environment 

Device: nrf9160dk customized one

NCS: v1.9.1

Please tell me how to verify it?

Best Regards
Praveen Deshmane  

[dejans]

Hi,

There is configuration option CONFIG_FMFU_FDEV_SKIP_PREVALIDATION which skips the prevalidation of the modem firmware. You can find it in the code available online. The verification of the modem firmware signature is done using nrf_modem_bootloader_verify() which is described in API documentation.

Best regards,
Dejan

[Praveen Deshmane]

Hello dejans,

thank you for replying.

I think, there is a miss communication.

my question is 

how to check that the downloaded full modem update file (.cbor file) is in external flash memory?

 

best regards 

praveen

[dejans]

Hi,

Inside fmfu_fdev.c, there is a function fmfu_fdev_load() which reads cbor header, gets the hash from the manifest, checks the hash and proceeds with install using load_segments().

Best regards,
Dejan

[Praveen Deshmane]

Hi Dejans,

thank you for your reply.

I would like to know how to check the downloaded file app_update.bin is in mucboot secondary (in my case it is in external flash memory which is of 8MB).

Best Regards

Praveen Deshmane 

[dejans]

Hi,

There is a function boot_read_bank_header() which reads MCUboot image header information.

Best regards,
Dejan