Golioth Multi MCU OTA Updates

Overview

An experimental project based on the Golioth fw_update sample that demonstrates how to update an auxiliary MCU from the main MCU utilizing SMP (Simple Management Protocol).

The main MCU is nRF9160 DK running an SMP Client and is responsible for downloading the auxiliary MCUs image and transfering it over UART interface. The auxiliary MCU is the nRF52840 DK, running the SMP Server sample.

Hardware

Both the nRF9160 DK and nRF52840 DK use uart1 interface for communication.

Connect nRF9160 DK and nRF52840 DK using wires:

nRF9160 DK	nRF52840 DK
P0.00 (RX)	P1.02 (TX)
P0.01 (TX)	P1.01 (RX)
GND	GND

Requirements

• Golioth credentials
• Network connectivity

Local set up

Do not clone this repo using git. Zephyr's west meta tool should be used to set up your local workspace.

Install the Python virtual environment (recommended)

cd ~
mkdir golioth-multi-mcu-update
python -m venv golioth-multi-mcu-update/.venv
source golioth-multi-mcu-update/.venv/bin/activate
pip install wheel west

Use west to initialize and install

cd ~/golioth-multi-mcu-update
west init -m git@github.com:goliothlabs/multi-mcu-fw-update.git .
west update
west zephyr-export
pip install -r deps/zephyr/scripts/requirements.txt

Apply Golioth Firmware SDK Patch

Apply the patch to add experimental support for multi MCU updates to Golioth Firmware SDK.

cd ~/golioth-multi-mcu-update/deps/zephyr
git am ../../app/0001-Zephyr-SMP-SVR-Example.patch

Apply Zephyr SMP Server Sample Patch

Apply the patch to add support for nRF52840 DK to the SMP Server sample.

cd ~/golioth-multi-mcu-update/deps/modules/lib/golioth-firmware-sdk
git am ../../../../app/0001-Golioth-Firmware-SDK-patch.patch

Creating a Release in the Golioth Console

Build an application with MCUBoot for nRF52840 DK.

When creating the Artifact let the Package name be: aux-mcu.

Building and Running

Building the application for nRF9160 DK

$ (.venv) cd ~/golioth-multi-mcu-update
$ (.venv) west build -p -b nrf9160dk_nrf9160_ns app --

Building the application for nRF52840 DK

$ (.venv) cd ~/golioth-multi-mcu-update/deps/zephyr/samples/subsys/mgmt/mcumgr/smp_svr
$ (.venv) west build -p -b nrf52840dk_nrf52840 -- -DEXTRA_CONF_FILE='overlay-serial.conf'

Authentication specific configuration

PSK based auth - Hardcoded

Configure the following Kconfig options based on your Golioth credentials:

• GOLIOTH_SAMPLE_PSK_ID - PSK ID of registered device
• GOLIOTH_SAMPLE_PSK - PSK of registered device

by chaning these lines in the configuration file:

CONFIG_GOLIOTH_SAMPLE_PSK_ID="psk-id"
CONFIG_GOLIOTH_SAMPLE_PSK="psk"

PSK based auth - Runtime

We provide an option for setting Golioth credentials through the Zephyr shell. This is based on the Zephyr Settings subsystem.

Add the following options to prj.conf:

CONFIG_GOLIOTH_SAMPLE_PSK_ID="psk-id"
CONFIG_GOLIOTH_SAMPLE_PSK="psk"
CONFIG_GOLIOTH_SAMPLE_HARDCODED_CREDENTIALS=n
CONFIG_FLASH=y
CONFIG_FLASH_MAP=y
CONFIG_NVS=y
CONFIG_SETTINGS=y
CONFIG_SETTINGS_RUNTIME=y
CONFIG_GOLIOTH_SAMPLE_PSK_SETTINGS=y
CONFIG_GOLIOTH_SAMPLE_WIFI_SETTINGS=y
CONFIG_GOLIOTH_SAMPLE_SETTINGS_AUTOLOAD=y
CONFIG_GOLIOTH_SAMPLE_SETTINGS_SHELL=y

At runtime, configure PSK-ID and PSK using the device shell based on your Golioth credentials:

uart:~$ settings set golioth/psk-id <my-psk-id@my-project>
uart:~$ settings set golioth/psk <my-psk>
uart:-$ kernel reboot cold

Certificate based auth

Configure the following Kconfig options based on your Golioth credentials:

• CONFIG_GOLIOTH_AUTH_METHOD_CERT - use certificate-based

  authentication

• CONFIG_GOLIOTH_SAMPLE_HARDCODED_CRT_PATH - device certificate
• CONFIG_GOLIOTH_SAMPLE_HARDCODED_KEY_PATH - device private key

by adding these lines to configuration file (e.g. prj.conf):

CONFIG_GOLIOTH_AUTH_METHOD_CERT=y
CONFIG_GOLIOTH_SAMPLE_HARDCODED_CRT_PATH="keys/device.crt.der"
CONFIG_GOLIOTH_SAMPLE_HARDCODED_KEY_PATH="keys/device.key.der"

Sample output

A sample output from the serial console is found below.

The device initially reports firmware version 1.2.3 and about 90 seconds later it receives notification of a new firmware release (1.2.4) from Golioth which triggers the update process.

After a successful update the new version number will be printed out on the serial terminal and displayed on the Golioth web console.

nRF9160 DK output

*** Booting nRF Connect SDK v2.5.2 ***
[00:00:00.513,336] <dbg> fw_update_sample: main: Start FW Update sample
[00:00:00.513,366] <inf> golioth_samples: Waiting to obtain IP address
[00:00:06.040,618] <inf> lte_monitor: Network: Searching
[00:00:08.239,471] <inf> lte_monitor: Network: Registered (home)
[00:00:08.240,570] <inf> golioth_mbox: Mbox created, bufsize: 1232, num_items: 10, item_size: 112
[00:00:08.241,333] <inf> golioth_fw_update: Current firmware version: aux-mcu - 1.2.3
[00:00:09.939,239] <inf> golioth_coap_client_zephyr: Golioth CoAP client connected
[00:00:09.939,544] <inf> fw_update_sample: Golioth client connected
[00:00:09.939,544] <inf> golioth_coap_client_zephyr: Entering CoAP I/O loop
[00:00:10.202,636] <inf> golioth_fw_update: Waiting to receive OTA manifest
[00:00:10.606,109] <inf> golioth_fw_update: Received OTA manifest
[00:00:10.606,170] <inf> golioth_fw_update: Current version = 1.2.3, Target version = 3.0.1
[00:00:10.606,201] <inf> golioth_fw_update: State = Downloading
[00:00:10.856,567] <inf> golioth_fw_update: Image size = 71943
[00:00:10.856,689] <inf> fw_block_processor: Downloading block index 0 (1/71)
[00:00:11.926,605] <inf> mcuboot_util: Image index: 0, Swap type: none
[00:00:11.926,635] <inf> golioth_fw_zephyr: swap type: none
[00:00:12.024,475] <inf> fw_block_processor: Downloading block index 1 (2/71)
[00:00:12.889,892] <inf> fw_block_processor: Downloading block index 2 (3/71)
...

[00:00:58.114,654] <inf> fw_block_processor: Downloading block index 69 (70/71)
[00:00:58.778,228] <inf> fw_block_processor: Downloading block index 70 (71/71)
[00:01:00.005,859] <inf> golioth_fw_update: Download took 49149 ms
[00:01:00.005,889] <inf> fw_block_processor: Block Latency Stats:
[00:01:00.005,889] <inf> fw_block_processor:    Min: 434 ms
[00:01:00.005,920] <inf> fw_block_processor:    Ave: %.3f ms
[00:01:00.005,920] <inf> fw_block_processor:    Max: 1070 ms
[00:01:00.005,950] <inf> fw_block_processor: Total bytes written: 71943
[00:01:00.095,275] <inf> golioth_fw_update: State = Downloaded
[00:01:00.578,552] <inf> golioth_fw_update: State = Updating
[00:01:00.858,551] <inf> fw_update_sample: Sending the image to AUX MCU
[00:01:13.976,562] <inf> fw_update_sample: Confirming the AUX image..
[00:01:14.016,448] <inf> mcumgr_grp_img_client: User configured image list buffer size 1 can't store all info
[00:01:14.016,510] <inf> fw_update_sample: Reset the AUX MCU ...

nRF52840 DK output

*** Booting nRF Connect SDK v2.5.2 ***
I: Starting bootloader
I: Primary image: magic=good, swap_type=0x3, copy_done=0x1, image_ok=0x1
I: Secondary image: magic=unset, swap_type=0x1, copy_done=0x3, image_ok=0x3
I: Boot source: none
I: Image index: 0, Swap type: none
I: Bootloader chainload address offset: 0xc000
*** Booting nRF Connect SDK v2.5.2 ***

After reseting the board:

[00:00:01.001,861] <inf> hello_update: Hello World! nrf52840dk_nrf52840
[00:00:02.002,014] <inf> hello_update: Hello World! nrf52840dk_nrf52840
[00:00:03.002,227] <inf> hello_update: Hello World! nrf52840dk_nrf52840
[00:00:04.002,380] <inf> hello_update: Hello World! nrf52840dk_nrf52840