Secure vs Non-Secure Build for Modem Firmware Update(NRF9160, Zephyr RTOS)

[Siddharth Kachhia]

Hi, I'm working on nRF9160 modem firmware update.

I have used nRF9160: Full modem firmware update using SMP Server demo and compiled it for nRF9160dk board.
While compilation, I received an error of non-secure firmware must be need to compile nrf_modem_lib in demo example.
Therefore to update modem, must use non-secure board only to compile SMP server demo for nRF9160 board.

Question:
1) Can I perform DFU of modem in nRF9160 board without non-secure image ?
2) Why nrf_modem_lib need non-secure board and not working with secure board ?
3) What is the difference between secure vs non-secure build ?
4) How can I use nrf_modem_lib for nRF9160 secure board ?

[Hakon]

Hello,

1) Can I perform DFU of modem in nRF9160 board without non-secure image ?

No, it's not possible.

2) Why nrf_modem_lib need non-secure board and not working with secure board ?

The application can only communicate with the modem in non-secure mode (hardware implementation restriction)

3) What is the difference between secure vs non-secure build ?

There is a lot of information about this in the documentation. You can start by reading this.

4) How can I use nrf_modem_lib for nRF9160 secure board ?

This is not possible, as the communication channels require non-secure.