nrfconnect · tomchy · Oct 3, 2025 · Oct 3, 2025 · Oct 3, 2025
@@ -39,6 +39,7 @@ if(CONFIG_NCS_IS_VARIANT_IMAGE)
 
     # Modify the CONFIG_FLASH_LOAD_OFFSET and CONFIG_FLASH_LOAD_SIZE for both the .config and autoconf.h files.
     # If partition manager is not used, these values should be taken from the device tree.
+    # Additionally, convert primary slot dependencies to secondary slot dependencies.
     set(dotconfig_variant_content)
     foreach(line IN LISTS dotconfig_content)
       if("${line}" MATCHES "^CONFIG_FLASH_LOAD_OFFSET=.*$")
@@ -49,6 +50,10 @@ if(CONFIG_NCS_IS_VARIANT_IMAGE)
         string(REGEX REPLACE "CONFIG_FLASH_LOAD_SIZE=(.*)" "CONFIG_FLASH_LOAD_SIZE=${code_partition_size}" line ${line})
       endif()
 
+      if("${line}" MATCHES "(--dependencies|-d).*\([0-9, ]+primary[0-9., ]+\)")
+        string(REGEX REPLACE "primary" "secondary" line ${line})
+      endif()
+
       list(APPEND dotconfig_variant_content "${line}\n")
     endforeach()
 
@@ -62,6 +67,10 @@ if(CONFIG_NCS_IS_VARIANT_IMAGE)
         string(REGEX REPLACE "#define CONFIG_FLASH_LOAD_SIZE (.*)" "#define CONFIG_FLASH_LOAD_SIZE ${code_partition_size}" line ${line})
       endif()
 
+      if("${line}" MATCHES "(--dependencies|-d).*\([0-9, ]+primary[0-9., ]+\)")
+        string(REGEX REPLACE "primary" "secondary" line ${line})
+      endif()
+
       list(APPEND autoconf_variant_content "${line}\n")
     endforeach()
 

@@ -193,6 +193,7 @@ function(dfu_app_zip_package)
     # Network core
     get_property(image_name GLOBAL PROPERTY DOMAIN_APP_CPUNET)
     set(net_update_name "${image_name}.bin")
+    set(secondary_net_update_name "${image_name}_secondary_app.bin")
     sysbuild_get(net_core_board IMAGE ${image_name} VAR BOARD CACHE)
 
     if(SB_CONFIG_SECURE_BOOT_NETCORE)
@@ -204,42 +205,76 @@ function(dfu_app_zip_package)
     mcuboot_image_number_to_slot(net_update_slot_primary ${SB_CONFIG_MCUBOOT_NETWORK_CORE_IMAGE_NUMBER} n)
     mcuboot_image_number_to_slot(net_update_slot_secondary ${SB_CONFIG_MCUBOOT_NETWORK_CORE_IMAGE_NUMBER} y)
 
-    if(SB_CONFIG_PARTITION_MANAGER)
-      set(net_load_address "$<TARGET_PROPERTY:partition_manager,CPUNET_PM_APP_ADDRESS>")
-    else()
-      get_address_from_dt_partition_nodelabel("slot${net_update_slot_primary}_partition"
-                                              net_load_address
-                                             )
-    endif()
+    if(NOT SB_CONFIG_MCUBOOT_BUILD_DIRECT_XIP_VARIANT)
+      if(SB_CONFIG_PARTITION_MANAGER)
+        set(net_load_address "$<TARGET_PROPERTY:partition_manager,CPUNET_PM_APP_ADDRESS>")
+      else()
+        get_address_from_dt_partition_nodelabel("slot${net_update_slot_primary}_partition"
+                                                net_load_address
+                                               )
+      endif()
 
-    math(EXPR net_update_slot_primary "${net_update_slot_primary} + 1")
-    math(EXPR net_update_slot_secondary "${net_update_slot_secondary} + 1")
+      math(EXPR net_update_slot_primary "${net_update_slot_primary} + 1")
+      math(EXPR net_update_slot_secondary "${net_update_slot_secondary} + 1")
+
+      set(generate_script_app_params
+          ${generate_script_app_params}
+          "${net_update_name}image_index=${SB_CONFIG_MCUBOOT_NETWORK_CORE_IMAGE_NUMBER}"
+          "${net_update_name}slot_index_primary=${net_update_slot_primary}"
+          "${net_update_name}slot_index_secondary=${net_update_slot_secondary}"
+          "${net_update_name}load_address=${net_load_address}"
+          "${net_update_name}version=${net_update_version}"
+          "${net_update_name}board=${net_core_board}"
+          "${net_update_name}soc=${SB_CONFIG_SOC}"
+         )
+
+      if(SB_CONFIG_SECURE_BOOT_NETCORE)
+        list(APPEND bin_files "${CMAKE_BINARY_DIR}/signed_by_mcuboot_and_b0_${image_name}.bin")
+        list(APPEND signed_targets ${image_name}_signed_packaged_target)
+      else()
+          sysbuild_get(net_CONFIG_KERNEL_BIN_NAME IMAGE ${image_name} VAR CONFIG_KERNEL_BIN_NAME KCONFIG)
+          if(SB_CONFIG_BOOT_ENCRYPTION)
+            list(APPEND bin_files "${CMAKE_BINARY_DIR}/${image_name}/zephyr/${net_CONFIG_KERNEL_BIN_NAME}.signed.encrypted.bin")
+          else()
+            list(APPEND bin_files "${CMAKE_BINARY_DIR}/${image_name}/zephyr/${net_CONFIG_KERNEL_BIN_NAME}.signed.bin")
+          endif()
+      endif()
+
+      list(APPEND zip_names "${net_update_name}")
+      list(APPEND signed_targets ${image_name}_extra_byproducts)
+    elseif(NOT SB_CONFIG_PARTITION_MANAGER)
+      get_address_from_dt_partition_nodelabel("slot${net_update_slot_primary}_partition" primary_net_load_address)
+      get_address_from_dt_partition_nodelabel("slot${net_update_slot_secondary}_partition" secondary_net_load_address)
 
-    set(generate_script_app_params
+      # Radio in DirectXIP mode
+      set(generate_script_app_params
         ${generate_script_app_params}
-        "${net_update_name}image_index=${SB_CONFIG_MCUBOOT_NETWORK_CORE_IMAGE_NUMBER}"
-        "${net_update_name}slot_index_primary=${net_update_slot_primary}"
-        "${net_update_name}slot_index_secondary=${net_update_slot_secondary}"
-        "${net_update_name}load_address=${net_load_address}"
-        "${net_update_name}version=${net_update_version}"
-        "${net_update_name}board=${net_core_board}"
-        "${net_update_name}soc=${SB_CONFIG_SOC}"
-       )
+          "${net_update_name}load_address=${primary_net_load_address}"
+          "${net_update_name}version_MCUBOOT+XIP=${CONFIG_MCUBOOT_IMGTOOL_SIGN_VERSION}"
+          "${net_update_name}image_index=${SB_CONFIG_MCUBOOT_NETWORK_CORE_IMAGE_NUMBER}"
+          "${net_update_name}slot=${net_update_slot_primary}"
+          "${secondary_net_update_name}load_address=${secondary_net_load_address}"
+          "${secondary_net_update_name}image_index=${SB_CONFIG_MCUBOOT_NETWORK_CORE_IMAGE_NUMBER}"
+          "${secondary_net_update_name}slot=${net_update_slot_secondary}"
+          "${secondary_net_update_name}version_MCUBOOT+XIP=${CONFIG_MCUBOOT_IMGTOOL_SIGN_VERSION}"
+        )
+      list(APPEND bin_files
+           "${CMAKE_BINARY_DIR}/${image_name}/zephyr/${CONFIG_KERNEL_BIN_NAME}.signed.bin"
+           "${CMAKE_BINARY_DIR}/${image_name}_secondary_app/zephyr/${CONFIG_KERNEL_BIN_NAME}.signed.bin"
+      )
+      set(exclude_files EXCLUDE
+          ${CMAKE_BINARY_DIR}/${image_name}/zephyr/${CONFIG_KERNEL_BIN_NAME}.signed.bin
+          ${CMAKE_BINARY_DIR}/${image_name}_secondary_app/zephyr/${CONFIG_KERNEL_BIN_NAME}.signed.bin
+      )
+      set(include_files INCLUDE
+          ${CMAKE_BINARY_DIR}/${image_name}/zephyr/${CONFIG_KERNEL_BIN_NAME}.bin
+          ${CMAKE_BINARY_DIR}/${image_name}_secondary_app/zephyr/${CONFIG_KERNEL_BIN_NAME}.bin
+      )
 
-    if(SB_CONFIG_SECURE_BOOT_NETCORE)
-      list(APPEND bin_files "${CMAKE_BINARY_DIR}/signed_by_mcuboot_and_b0_${image_name}.bin")
-      list(APPEND signed_targets ${image_name}_signed_packaged_target)
-    else()
-        sysbuild_get(net_CONFIG_KERNEL_BIN_NAME IMAGE ${image_name} VAR CONFIG_KERNEL_BIN_NAME KCONFIG)
-        if(SB_CONFIG_BOOT_ENCRYPTION)
-          list(APPEND bin_files "${CMAKE_BINARY_DIR}/${image_name}/zephyr/${net_CONFIG_KERNEL_BIN_NAME}.signed.encrypted.bin")
-        else()
-          list(APPEND bin_files "${CMAKE_BINARY_DIR}/${image_name}/zephyr/${net_CONFIG_KERNEL_BIN_NAME}.signed.bin")
-        endif()
+      list(APPEND zip_names "${net_update_name};${secondary_net_update_name}")
+      list(APPEND signed_targets ${image_name}_extra_byproducts)
+      list(APPEND signed_targets ${image_name}_secondary_app_extra_byproducts)
     endif()
-
-    list(APPEND zip_names "${net_update_name}")
-    list(APPEND signed_targets ${image_name}_extra_byproducts)
   endif()
 
   if(SB_CONFIG_DFU_ZIP_WIFI_FW_PATCH)

@@ -0,0 +1,24 @@
+#
+# Copyright (c) 2025 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+
+cmake_minimum_required(VERSION 3.20.0)
+
+find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
+project(ab_split)
+
+target_sources(app PRIVATE src/main.c)
+target_sources(app PRIVATE src/ab_utils.c)
+
+target_include_directories(
+    app PRIVATE
+    ${ZEPHYR_MCUBOOT_MODULE_DIR}/boot/bootutil/include
+    ${ZEPHYR_MCUBOOT_MODULE_DIR}/boot/zephyr/include
+    ${ZEPHYR_BASE}/samples/subsys/mgmt/mcumgr/smp_svr/src
+  )
+
+target_sources_ifdef(CONFIG_MCUMGR_TRANSPORT_BT app PRIVATE
+                     ${ZEPHYR_BASE}/samples/subsys/mgmt/mcumgr/smp_svr/src/bluetooth.c)
@@ -0,0 +1,14 @@
+#
+# Copyright (c) 2025 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+config N_BLINKS
+	int "Number of fast blinks"
+	default 1
+
+config EMULATE_APP_HEALTH_CHECK_FAILURE
+	bool "Blocks confirmation of being healthy after the update"
+
+source "Kconfig.zephyr"
@@ -0,0 +1,194 @@
+.. _ab_split_sample:
+
+A/B with MCUboot and separated slots
+####################################
+
+.. contents::
+   :local:
+   :depth: 2
+
+The A/B with MCUboot and separated slots sample demonstrates how to configure the application for updates using the A/B method using MCUboot.
+This sample is a variant of the :ref:`A/B sample <ab_sample>`, where the application and radio images are not merged, but reside in separate MCUboot slots.
+This split increases demand on the number of memory areas that should be individually locked from accidental writes as well as requires additional care when preparing updates, so only a compatible set of slots are booted.
+The additional dependency check during the boot process increases the time to boot the system.
+
+It also includes an example to perform a device health check before confirming the image after the update.
+You can update the sample using the Simple Management Protocol (SMP) with UART or Bluetooth® Low Energy.
+
+To prevent the build system from merging slots, the sysbuild :kconfig:option:`SB_CONFIG_MCUBOOT_SIGN_MERGED_BINARY` option is disabled.
+To enable slot-based dependency management, the :kconfig:option:`CONFIG_BOOT_VERSION_CMP_USE_SLOT_NUMBER` option is enabled in the :file:`sysbuild/mcuboot/prj.conf` file.
+
+Requirements
+************
+
+The sample supports the following development kits:
+
+.. table-from-sample-yaml::
+
+You need the nRF Device Manager app for update over Bluetooth Low Energy:
+
+* `nRF Device Manager mobile app for Android`_
+* `nRF Device Manager mobile app for iOS`_
+
+
+Overview
+********
+
+This sample demonstrates firmware update using the A/B method.
+This method allows two copies of the application in the NVM memory.
+It is possible to switch between these copies without performing a swap, which significantly reduces time of device's unavailability during the update.
+The switch between images can be triggered by the application or, for example, by a hardware button.
+
+This sample implements an SMP server.
+SMP is a basic transfer encoding used with the MCUmgr management protocol.
+For more information about MCUmgr and SMP, see :ref:`device_mgmt`.
+
+The sample supports the following MCUmgr transports by default:
+
+* Bluetooth
+* Serial (UART)
+
+A/B functionality
+=================
+
+When the A/B with separated slots functionality is used, the device has two slots for each application and radio firmwares: slot A and slot B.
+The slots are equivalent, and the device can boot from either of them.
+By design, the slot A of the application image boots the slot A of the radio image, so there is a slot-based dependency required to correctly verify the correctness of the images.
+In the case of MCUboot, this is achieved by using the Direct XIP feature.
+Thus, note that the terms slot 0, primary slot, slot A and slot 1, secondary slot, slot B are used interchangeably throughout the documentation.
+This configuration allows a background update of the non-active slot while the application runs from the active slot.
+After the update is complete, the device can quickly switch to the updated slot on the next reboot.
+
+The following conditions decide which slot will be booted (active) on the next reboot:
+
+1. If one of the slots contains a valid image, it is marked as valid only if the same slot of the other image is also valid.
+#. If one of the slots is not valid, the other slot is selected as active.
+#. If both slots are valid, the slot marked as "preferred" is selected as active.
+#. If both slots are valid and none is marked as "preferred," the slot with the higher version number is selected as active.
+#. If none of the above conditions is met, slot A is selected as active.
+
+You can set the preferred slot using the ``boot_request_set_preferred_slot`` function.
+Currently, this only sets the boot preference for a single reboot.
+
+Identifying the active slot
+---------------------------
+
+If the project uses the Partition Manager, the currently running slot can be identified by checking if ``CONFIG_NCS_IS_VARIANT_IMAGE`` is defined.
+If it is defined, the application is running from slot B.
+Otherwise, it is running from slot A.
+
+If the project does not use the Partition Manager (a configuration currently only supported on the nRF54H20), the currently running slot can be identified by comparing the address pointed `zephyr,code-partition` to specific node addresses defined in the device tree.
+The following node partitions are used by default:
+
+* ``cpuapp_slot0_partition`` - Application core, slot A
+* ``cpuapp_slot1_partition`` - Application core, slot B
+* ``cpurad_slot0_partition`` - Radio core, slot A
+* ``cpurad_slot1_partition`` - Radio core, slot B
+
+For example, verifying that the application is running from slot A can be done by using the following macro:
+
+.. code-block:: c
+
+    #define IS_RUNNING_FROM_SLOT_A \
+        (FIXED_PARTITION_NODE_OFFSET(DT_CHOSEN(zephyr_code_partition)) == \
+         FIXED_PARTITION_OFFSET(cpuapp_slot0_partition))
+
+.. _ab_split_build_files:
+
+Build files
+-----------
+
+This sample overrides the default build strategy, so application and radio images are built separately. 
+In this case, the following files should be sent to the device when performing an update:
+
+* :file:`build/mcuboot_secondary_app/zephyr/zephyr.signed.bin` - Contains the slot B of the application image.
+  This file should be uploaded to the secondary slot when the device is running from slot A.
+* :file:`build/ipc_radio_secondary_app/zephyr/zephyr.signed.bin` - Contains the slot B of the radio image.
+  This file should be uploaded to the secondary slot when the device is running from slot A.
+* :file:`build/ab/zephyr/zephyr.signed.bin` - Contains the slot A of the application image.
+  This file should be uploaded to the primary slot when the device is running from slot B.
+* :file:`build/ipc_radio/zephyr/zephyr.signed.bin` - Contains the slot A of the radio image.
+  This file should be uploaded to the primary slot when the device is running from slot B.
+
+User interface
+**************
+
+LED 0:
+    This LED indicates that the application is running from slot A.
+    It is controlled as active low, meaning it will turn on once the application is booted and blinks (turns off) in short intervals.
+    The number of short blinks is configurable using the :kconfig:option:`CONFIG_N_BLINKS` Kconfig option.
+    It will remain off if the application is running from slot B.
+
+LED 1:
+    This LED indicates that the application is running from slot B.
+    It is controlled as active low, meaning it will turn on once the application is booted and blinks (turns off) in short intervals.
+    The number of short blinks is configurable using the :kconfig:option:`CONFIG_N_BLINKS` Kconfig option.
+    It will remain off if the application is running from slot A.
+
+Button 0:
+    By pressing this button, the non-active slot will be selected as the preferred slot on the next reboot.
+    This preference applies only to the next boot and is cleared after the subsequent reset.
+
+Configuration
+*************
+
+|config|
+
+Configuration options
+=====================
+
+Check and configure the following configuration option for the sample:
+
+.. _CONFIG_N_BLINKS:
+
+CONFIG_N_BLINKS - The number of blinks.
+   This configuration option sets the number of times the LED corresponding to the currently active slot blinks (LED0 for slot A, LED1 for slot B).
+   The default value of the option is set to ``1``, causing a single blink to indicate *Version 1*.
+   You can increment this value to represent an update, such as set it to ``2`` to indicate *Version 2*.
+
+.. _CONFIG_EMULATE_APP_HEALTH_CHECK_FAILURE:
+
+CONFIG_EMULATE_APP_HEALTH_CHECK_FAILURE - Enables emulation of a broken application that fails the self-test.
+   This configuration option emulates a broken application that does not pass the self-test.
+
+Additional configuration
+========================
+
+Check and configure the :kconfig:option:`CONFIG_MCUBOOT_IMGTOOL_SIGN_VERSION` library Kconfig option specific to the MCUboot library.
+This configuration option sets the version to pass to imgtool when signing.
+To ensure the updated build is preferred after a DFU, set this option to a higher version than the version currently running on the device.
+
+In addition, set the :kconfig:option:`CONFIG_MCUBOOT_EXTRA_IMGTOOL_ARGS` library Kconfig option specific to the MCUboot library to specify the slot-specific image dependencies.
+For example, to ensure that there is a valid radio image with version ``1.0.0`` or greater in the radio primary slot set:
+
+.. code-block:: console
+
+    CONFIG_MCUBOOT_EXTRA_IMGTOOL_ARGS="--dependencies \"(0,primary,1.0.0)\""
+
+The slot-specific dependency is automatically converted to point to the secondary slot when building the second variant of each image.
+
+Building and running
+********************
+
+.. |sample path| replace:: :file:`samples/dfu/ab`
+
+.. include:: /includes/build_and_run.txt
+
+Testing
+=======
+
+To perform DFU using the `nRF Connect Device Manager`_ mobile app, complete the following steps:
+
+.. include:: /app_dev/device_guides/nrf52/fota_update.rst
+   :start-after: fota_upgrades_over_ble_nrfcdm_common_dfu_steps_start
+   :end-before: fota_upgrades_over_ble_nrfcdm_common_dfu_steps_end
+
+Instead of using the :file:`dfu_application.zip` file, you can also send the appropriate binary file directly, as described in :ref:`ab_build_files`.
+Make sure to select the correct file based on the currently running slot.
+
+Dependencies
+************
+
+This sample uses the following |NCS| library:
+
+* :ref:`MCUboot <mcuboot_index_ncs>`
@@ -0,0 +1,13 @@
+/*
+ * Copyright (c) 2025 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+ */
+
+#include "../sysbuild/nrf54h20dk_nrf54h20_memory_map.dtsi"
+
+/ {
+	chosen {
+		zephyr,boot-mode = &boot_request;
+	};
+};