USB DFU using AuTerm Unable to switch between images in two slots

[Shuhao Dong]

Hello, I am test DFU USB function with my Thingy53. So far, I have been able to add DFU USB support from my application but not from the MCUboot. I am using the recommended AuTerm (v0.35a) to upload and read images. I can successfully upload the "signed_by_mcuboot_and_b0_ipc_radio.bin" file with the Test option, and this could be confirmed by reading images again as shown in the figure.  But from the terminal output, I can see an error and two inf log outputs as shown: 

[00:07:32.896,820] <inf> mcuboot_util: Image index: 0, Swap type: test
[00:07:32.897,888] <inf> mcuboot_util: Image index: 1, Swap type: none
[00:07:32.897,918] <err> mcumgr_img_grp: Failed to open flash area ID 1: -2

I found a similar issue about this error code here (https://devzone.nordicsemi.com/f/nordic-q-a/108054/flash-area-error-while-doing-dfu-using-nrf-connect), and my conclusion from this post is that this error should not affect the DFU process.

But after I issue a reset command, what I should expect is that the two images swapped. But what happens is: 1) This time I only have one image in slot 0, there is no slot 1 anymore. 2) the log information in the terminal change to:

[00:00:16.194,580] <inf> mcuboot_util: Image index: 0, Swap type: none
[00:00:16.195,220] <inf> mcuboot_util: Image index: 1, Swap type: none
[00:00:16.195,251] <err> mcumgr_img_grp: Failed to open flash area ID 1: -2

, which suggests both images are not swapable I assume? By checking the hash number of the image in slot 0 after reset, I can confirm it is the same image in slot 0 before I issue a reset command. So what happened is, after I issued a reset, the image in slot 1 just disappered while image in slot 0 is active. I attached my prj.conf file here: 

CONFIG_GPIO=y

#Enable I2C
CONFIG_I2C=y
# Enable SPI
CONFIG_SPI=y

# Disable TFM
CONFIG_TFM_SECURE_UART=n
CONFIG_TFM_LOG_LEVEL_SILENCE=y

CONFIG_LOG=y
CONFIG_USE_SEGGER_RTT=y
CONFIG_LOG_BACKEND_RTT=y    
CONFIG_LOG_BACKEND_UART=y  
CONFIG_UART_RTT=y  
CONFIG_RTT_CONSOLE=y    
CONFIG_STDOUT_CONSOLE=y
CONFIG_SEGGER_RTT_BUFFER_SIZE_UP=4096  
CONFIG_LOG_BUFFER_SIZE=8192

# Enable Bluetooth LE
CONFIG_BT=y
CONFIG_BT_PERIPHERAL=y
CONFIG_BT_DEVICE_NAME="thingy53"
CONFIG_BT_BROADCASTER=y
CONFIG_BT_OBSERVER=y

# Increase stack size for the main thread and System Workqueue
CONFIG_SYSTEM_WORKQUEUE_STACK_SIZE=2048
CONFIG_MAIN_STACK_SIZE=10240

# Enale floating point unit for float point calculation 
CONFIG_FPU=y
CONFIG_CBPRINTF_FP_SUPPORT=y

# Enable debugging 
CONFIG_DEBUG_THREAD_INFO=y
CONFIG_DEBUG_OPTIMIZATIONS=y

# Enable multithread
CONFIG_MULTITHREADING=y

CONFIG_SENSOR=y
CONFIG_PWM=y
CONFIG_ADC=y

CONFIG_VOLTAGE_DIVIDER=y
CONFIG_NRFX_SAADC=y

# Enable USB
CONFIG_USB_DEVICE_STACK=y
CONFIG_USB_DEVICE_PRODUCT="thingy53"
CONFIG_USB_DEVICE_PID=0x0001
CONFIG_USB_DRIVER_LOG_LEVEL_ERR=y
CONFIG_USB_DEVICE_LOG_LEVEL_ERR=y
CONFIG_SERIAL=y
CONFIG_UART_INTERRUPT_DRIVEN=y
CONFIG_UART_LINE_CTRL=y
CONFIG_USB_DEVICE_INITIALIZE_AT_BOOT=y

# STEP 5.2 - Enable mcumgr DFU in application
# Enable MCUMGR 
CONFIG_MCUMGR=y

# Enable MCUMGR management for both OS and Images
CONFIG_MCUMGR_GRP_OS=y
CONFIG_MCUMGR_GRP_IMG=y

# Configure MCUMGR transport to UART
CONFIG_MCUMGR_TRANSPORT_UART=y

# Dependencies
# Configure dependencies for CONFIG_MCUMGR  
CONFIG_NET_BUF=y
CONFIG_ZCBOR=y
CONFIG_CRC=y

# Configure dependencies for CONFIG_MCUMGR_GRP_IMG  
CONFIG_FLASH=y
CONFIG_IMG_MANAGER=y

# Configure dependencies for CONFIG_IMG_MANAGER  
CONFIG_STREAM_FLASH=y
CONFIG_FLASH_MAP=y

# Configure dependencies for CONFIG_MCUMGR_TRANSPORT_UART 
CONFIG_BASE64=y

I am using nrf connect sdk v2.7.0 and toolchain v2.7.0

[Sigurd Hellesvik]

Hi,

"signed_by_mcuboot_and_b0_ipc_radio.bin" file with the Test option

Netcore DFU does not support Reverting. Use "Confirm" instead of "Test".

 But from the terminal output, I can see an error and two inf log outputs as shown: 

This is typically due to not found secondary slot in MCUboot, usually external flash.

Are your external flash set up properly for MCUboot?

See https://academy.nordicsemi.com/courses/nrf-connect-sdk-intermediate/lessons/lesson-9-bootloaders-and-dfu-fota/topic/exercise-5-fota-over-bluetooth-low-energy/ for a guide (At the bottom is a section for the nRF5340.

Regards,
Sigurd Hellesvik

[Shuhao Dong]

Thank you Sigurd. I have configured a secondary slot in my sysbuild.conf using: SB_CONFIG_MCUBOOT_MODE_SINGLE_APP=n and in the mcuboot.conf using: CONFIG_SINGLE_APPLICATION_SLOT=n. So do I have to use external flash for MCUboot? 

Another question is, if I want to enable serial recovery over USB, the size of my MCUboot parition is restricted by a static partition yaml file comes with zephyr, how can I increase the size of MCUboot partition size? I have tried to use the partition output file from my nrf5340dk's build, is this a valid approach? Thank you!

[Sigurd Hellesvik]

Aha, I missed that you were doing Serial Recovery.

I suggest that you start by trying to only DFU to application core. Does that work?

Shuhao Dong said:

Another question is, if I want to enable serial recovery over USB, the size of my MCUboot parition is restricted by a static partition yaml file comes with zephyr, how can I increase the size of MCUboot partition size? I have tried to use the partition output file from my nrf5340dk's build, is this a valid approach? Thank you!

It depends, do you program the Thingy with an external debugger or not?

[Shuhao Dong]

Hi Sigurd, I abandoned the AuTerm method and changed to dfu-util command line tool. Sorry to make it unclear before, but I do not want to use USB serial recovery. I only want to use USB DFU from application. Right now, I can confirm I could be able to update application core using dfu-util with zephyr.signed.bin. And after enabling 

CONFIG_USB_DFU_PERMANENT_DOWNLOAD=y
CONFIG_USB_DFU_REBOOT=y

, it seems like the device will automatically reboot and swap and confirm the new image. I have not yet tried to upgrade both cores using dfu-util. 

For the second question, since I am not using USB serial recovery, the size of mcuboot partition is large enough. But if I do want to add that feature in the future, I am programming using an external debugger on nrf5340dk. COuld you please suggest any solution to that? Many thanks. 

[Sigurd Hellesvik]

Shuhao Dong said:

But if I do want to add that feature in the future, I am programming using an external debugger on nrf5340dk. COuld you please suggest any solution to that?

If you want to program Serial Recovery later, see https://academy.nordicsemi.com/courses/nrf-connect-sdk-intermediate/lessons/lesson-8-bootloaders-and-dfu-fota/