Simultaneous multi-image DFU with nRF5340 DK

The simultaneous update of multiple images is available for testing since nRF Connect SDK v1.7.0. It allows the updating of both the application core and the network core in one go.

To enable the simultaneous update of multiple images by MCUboot, set the following options:

SB_CONFIG_SECURE_BOOT_NETCORE - Enables nRF Secure Immutable Bootloader for the network core.
SB_CONFIG_NETCORE_APP_UPDATE - Enables firmware updates for the network core.
SB_CONFIG_MCUBOOT_NRF53_MULTI_IMAGE_UPDATE - Performs network core updates in a single operation.

Note

The application core can be reverted, but doing so breaks the network core upon reversal, as the reversion process fills the network core with the content currently in the RAM that PCD uses.

Additionally, the memory partitions must be defined and include:

mcuboot_primary and mcuboot_secondary partitions for the application core image slots.
mcuboot_primary_1 and mcuboot_secondary_1 partitions for the network core image slots.
pcd_sram partition used for command exchange between the application core and the network core (see CONFIG_PCD_APP).

Note

The application core does not have direct access to the network core flash memory. The update image is passed indirectly using RAM. Because of this, the mcuboot_primary_1 must be stored in ram_flash region. To enable providing such region on the device, see CONFIG_FLASH_SIMULATOR.

Samples and applications built for Thingy:53 enable simultaneous update of multiple images by default. To learn more about Thingy:53, see Developing with Thingy:53.