test_mcuboot example - not switching

[Shahin97]

Hello, 

I am looking to have two applications in flash and switch between them using MCU boot using an nRF52832. The ultimate goal is to do BLE MESH DFU into external flash for larger applications but I thought I'd start with a simple switching between two applications already present in flash using MCU boot. 

I have found this Zephyr example in the connect SDK - C:\ncs\v2.3.0-rc1\zephyr\tests\boot

This looks like it'll fulfil my initial task of switching. The application builds successfully, however the MCU does not switch between the the applications.  Example UNCHANGED.

Terminal Log:

****** Booting Zephyr OS build v3.2.99-ncs2-rc1 ***
Launching primary slot application on nrf52dk_nrf52832
*** Booting Zephyr OS build v3.2.99-ncs2-rc1 ***
Launching primary slot application on nrf52dk_nrf52832
*** Booting Zephyr OS build v3.2.99-ncs2-rc1 ***
Launching primary slot application on nrf52dk_nrf52832
*** Booting Zephyr OS build v3.2.99-ncs2-rc1 ***
Launching primary slot application on nrf52dk_nrf52832
*** Booting Zephyr OS build v3.2.99-ncs2-rc1 ***
Launching primary slot application on nrf52dk_nrf52832
*** Booting Zephyr OS build v3.2.99-ncs2-rc1 ***
Launching primary slot application on nrf52dk_nrf52832
*** Booting Zephyr OS build v3.2.99-ncs2-rc1 ***
Launching primary slot application on nrf52dk_nrf52832
*** Booting Zephyr OS build v3.2.99-ncs2-rc1 ***
Launching primary slot application on nrf52dk_nrf52832
..
..
..

main.c application 1

#include <zephyr/kernel.h>
#include <zephyr/sys/reboot.h>
#include <zephyr/dfu/mcuboot.h>

/* Main entry point */
void main(void)
{
	printk("Launching primary slot application on %s\n", CONFIG_BOARD);
	/* Perform a permanent swap of MCUBoot application */
	boot_request_upgrade(1);
	printk("Secondary application ready for swap, rebooting\n");
	sys_reboot(SYS_REBOOT_COLD);
}

main.c application 2

#include <zephyr/kernel.h>

/* Main entry point */
void main(void)
{
    while(1){
	printk("Swapped application booted on %s\n\n\n\n", CONFIG_BOARD);
    }
}

Any thought?

[Shahin97]

I have a feeling that the second application is not flashed to the MCU, the IDE used is CLION, this is the nRF flash map

[Hieu]

Hi shahin97,

Rather than the secondary application not being flashed, it looks to me that the only thing in your flash memory is actually the first application. The green area above is likely some configuration data.

This project use sysbuild, which the VS Code extension does not handle very well. To build it, you need to follow the instruction here:
Sysbuild (System build) — Zephyr Project Documentation (nordicsemi.com).

That being said, in my test, even with all the images built and flashed, the sample would still not work. The main application can detect the app to be swapped, but MCUboot cannot boot into the new app for some reasons. I am not 100% certain why at the moment.

Before we proceed any further, I notice you mentioning that this experiment is to get Bluetooth Mesh DFU to work somehow. I understand that you are talking about the nRF5 SDK for Mesh DFU solution. It is a completely different SDK. Do you have a plan to mix the SDKs together somehow?

Hieu

[Shahin97]

I am currently in the research stage of this project, the direction the project will go is still configurable, an so I am assessing different examples from Nordic to gain some background information regarding DFU. Coming from STM32 to Nordic, it is noticeably different, especially with Zephyr. MCUBOOT has intrigued me, Do you know where I can find an example using MCUBOOT for DFU specifically using the nRF52832. This board is a fixed parameter in the specification  

[Hieu]

It turns out that the test_mcuboot project is not intended for nRF device and the addresses in that project is incompatible with MCUboot. 

Shahin97 said:

Do you know where I can find an example using MCUBOOT for DFU specifically using the nRF52832.

The SMP Server is a sample NCS inherits from Zephyr that demonstrate DFU with MCUboot.

We have a blog post explaining how to add DFU to your application. The sections regarding BLE testing should also be useable for testing the SMP Server sample above.

Our colleague Sigurd also provides some small size MCUboot samples here: https://github.com/hellesvik-nordic/samples_for_nrf_connect_sdk/tree/main/bootloader_samples.

If you wish to learn more about MCUboot, please also take some time to read through its documentation:
MCUboot documentation in the nRF Connect SDK — MCUboot 1.9.99 documentation (nordicsemi.com).

This documentation is more relevant to two-stage bootloader setup, but also contains sections about MCUboot:
Bootloaders and Device Firmware Updates — nRF Connect SDK 2.2.0 documentation (nordicsemi.com).