mgmt: mcumgr: grp: os: Add active b0 slot bootloader info query

Allows querying the active b0 slot via MCUmgr so that the correct
update image can be loaded to a device

Signed-off-by: Jamie McCrae <jamie.mccrae@nordicsemi.no>

subsys/CMakeLists.txt

@@ -77,3 +77,4 @@ add_subdirectory(suit)
 add_subdirectory_ifdef(CONFIG_MGMT_SUITFU mgmt/suitfu)
 add_subdirectory_ifdef(CONFIG_DULT dult)
 add_subdirectory_ifdef(CONFIG_NRF_COMPRESS nrf_compress)
+add_subdirectory(mgmt/mcumgr)

subsys/Kconfig

@@ -28,6 +28,7 @@ rsource "nrf_rpc/Kconfig"
 rsource "zigbee/Kconfig"
 rsource "mgmt/fmfu/Kconfig"
 rsource "mgmt/suitfu/Kconfig"
+rsource "mgmt/mcumgr/Kconfig"
 rsource "caf/Kconfig"
 rsource "ieee802154/Kconfig"
 rsource "dm/Kconfig"

subsys/mgmt/mcumgr/CMakeLists.txt

@@ -0,0 +1,7 @@
+#
+# Copyright (c) 2024 Nordic Semiconductor
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+add_subdirectory(grp)

subsys/mgmt/mcumgr/Kconfig

@@ -0,0 +1,11 @@
+#
+# Copyright (c) 2024 Nordic Semiconductor
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+menu "Additional MCUmgr configuration"
+
+rsource "grp/Kconfig"
+
+endmenu

subsys/mgmt/mcumgr/grp/CMakeLists.txt

@@ -0,0 +1,7 @@
+#
+# Copyright (c) 2024 Nordic Semiconductor
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+add_subdirectory_ifdef(CONFIG_MCUMGR_GRP_OS os_mgmt)

subsys/mgmt/mcumgr/grp/Kconfig

@@ -0,0 +1,11 @@
+#
+# Copyright (c) 2024 Nordic Semiconductor
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+menu "Additional MCUmgr group configuration"
+
+rsource "os_mgmt/Kconfig"
+
+endmenu

subsys/mgmt/mcumgr/grp/os_mgmt/CMakeLists.txt

@@ -0,0 +1,10 @@
+#
+# Copyright (c) 2024 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+if(CONFIG_MCUMGR_GRP_OS_BOOTLOADER_INFO_B0_ACTIVE_SLOT)
+  zephyr_library_amend()
+  zephyr_library_sources(src/os_mgmt_b0_active_slot.c)
+endif()

subsys/mgmt/mcumgr/grp/os_mgmt/Kconfig

@@ -0,0 +1,22 @@
+#
+# Copyright (c) 2024 Nordic Semiconductor ASA
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+menu "Additional MCUmgr OS group management functionality"
+
+config MCUMGR_GRP_OS_BOOTLOADER_INFO_B0_ACTIVE_SLOT
+	bool "Bootloader info query for active b0 slot"
+	depends on MCUMGR_GRP_OS_BOOTLOADER_INFO
+	depends on BOOTLOADER_MCUBOOT
+	depends on MCUBOOT_MCUBOOT_IMAGE_NUMBER != -1
+	depends on FW_INFO
+	depends on FW_INFO_API
+	select MCUMGR_MGMT_NOTIFICATION_HOOKS
+	select MCUMGR_GRP_OS_BOOTLOADER_INFO_HOOK
+	help
+	  Enables a bootloader info command for `active_b0_slot` which will return the active b0
+	  image slot number, and can be used to determine which update image should be loaded.
+
+endmenu

subsys/mgmt/mcumgr/grp/os_mgmt/src/os_mgmt_b0_active_slot.c

@@ -0,0 +1,71 @@
+/*
+ * Copyright (c) 2024 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+ */
+
+#include <zcbor_common.h>
+#include <zcbor_encode.h>
+#include <pm_config.h>
+#include <fw_info.h>
+#include <zephyr/mgmt/mcumgr/mgmt/callbacks.h>
+#include <zephyr/mgmt/mcumgr/grp/os_mgmt/os_mgmt.h>
+
+static enum mgmt_cb_return bootloader_info_hook(uint32_t event, enum mgmt_cb_return prev_status,
+						int32_t *rc, uint16_t *group, bool *abort_more,
+						void *data, size_t data_size)
+{
+	struct os_mgmt_bootloader_info_data *bootloader_info_data =
+						(struct os_mgmt_bootloader_info_data *)data;
+
+	if (event != MGMT_EVT_OP_OS_MGMT_BOOTLOADER_INFO || data_size !=
+	    sizeof(*bootloader_info_data)) {
+		*rc = MGMT_ERR_EUNKNOWN;
+		return MGMT_CB_ERROR_RC;
+	}
+
+	/* If no parameter is recognized then just introduce the bootloader. */
+	if (*(bootloader_info_data->decoded) >= 1 && (sizeof("active_b0_slot") - 1) ==
+	    bootloader_info_data->query->len && memcmp("active_b0_slot",
+						       bootloader_info_data->query->value,
+						       bootloader_info_data->query->len) == 0) {
+		const struct fw_info *s0_info = fw_info_find(PM_S0_ADDRESS);
+		const struct fw_info *s1_info = fw_info_find(PM_S1_ADDRESS);
+
+		if (s0_info || s1_info) {
+			int active_slot;
+			bool ok;
+
+			if (!s1_info || (s0_info && s0_info->version >= s1_info->version)) {
+				active_slot = 0;
+			} else if (!s0_info || (s1_info && s1_info->version > s0_info->version)) {
+				active_slot = 1;
+			}
+
+			ok = zcbor_tstr_put_lit(bootloader_info_data->zse, "active") &&
+			     zcbor_int32_put(bootloader_info_data->zse, active_slot);
+			*rc = (ok ? MGMT_ERR_EOK : MGMT_ERR_EMSGSIZE);
+			return MGMT_CB_ERROR_RC;
+		}
+
+		/* Return reponse not valid error when active slot cannot be determined */
+		*group = MGMT_GROUP_ID_OS;
+		*rc = OS_MGMT_ERR_QUERY_RESPONSE_VALUE_NOT_VALID;
+		return MGMT_CB_ERROR_ERR;
+	}
+
+	return MGMT_CB_OK;
+}
+
+static struct mgmt_callback cmd_bootloader_info_cb = {
+	.callback = bootloader_info_hook,
+	.event_id = MGMT_EVT_OP_OS_MGMT_BOOTLOADER_INFO,
+};
+
+static int os_mgmt_register_bootloader_info_hook_b0_active_slot(void)
+{
+	mgmt_callback_register(&cmd_bootloader_info_cb);
+	return 0;
+}
+
+SYS_INIT(os_mgmt_register_bootloader_info_hook_b0_active_slot, APPLICATION, 0);