The official Mender documentation explains how Mender works. This is a board-specific complement to the official documentation.
Board description
PICO-PI-IMX7 is the Starting Kit for Android Things
The i.MX 7Dual delivers high-performance processing for low-power requirements with a high degree of functional integration. The i.MX 7Dual features an advanced implementation of two ARM®Cortex®-A7 cores, which operate at speeds of up to 1.2 GHz, as well as the ARM® Cortex®-M4 core. The Pico variant is pin-compatible with the Intel® Edison for sensors and low-speed I/O, but also adds additional expansion possibilities for multimedia and connectivity, giving you cutting edge technology that can easily be expanded and implemented for IoT designs.
URL:https://shop.technexion.com/pico-pi-imx7.html
Test results
The Yocto Project releases in the table below have been tested by the Mender community. Please update it if you have tested this integration on other Yocto Project releases:
| Yocto Project | Build | Runtime |
|---|---|---|
| sumo (2.5) |  |
|
| thud (2.6) | |
|
| warrior (2.7) | |
|
| zeus (3.0) | |
|
| dunfell (3.1) | |
|
Build Means that the Yocto Project build using this Mender integration completes without errors and outputs images.
Runtime Means that Mender has been verified to work on the board. For U-Boot-based boards, the integration checklist has been verified.
Getting started
Prerequisites
-
A supported Linux distribution and dependencies installed on your workstation/laptop as described in the Yocto Mega Manual
-
NOTE. Instructions depend on which Yocto version you intend to use.
-
Google repo tool installed and in your
PATH.
Configuring the build
Setup Yocto environment
Set the Yocto Project branch you are building for:
# set to your branch, make sure it is supported (see table above)
export BRANCH="dunfell"
Create a directory for your mender-nxp setup to live in and clone the
meta information.
mkdir mender-nxp && cd mender-nxp
Initialize repo manifest:
repo init -u https://github.com/mendersoftware/meta-mender-community \
-m meta-mender-nxp/scripts/manifest-nxp.xml \
-b ${BRANCH}
Fetch layers in manifest:
repo sync
Setup build environment
Initialize the build environment:
source setup-environment nxp
NOTE! You need to accept the Freescale EULA at ‘…/sources/meta-freescale/EULA’. Please read it and in case you accept it, add:
ACCEPT_FSL_EULA = "1"
in your local.conf.
Building the image
You can now proceed with building an image:
MACHINE=imx7d-pico bitbake core-image-base
Replace core-image-base with your desired image target.
Using the build output
After a successful build, the images and build artifacts are placed in tmp/deploy/images/imx7d-pico/.
-
tmp/deploy/images/imx7d-pico/core-image-base-imx7d-pico.sdimg -
tmp/deploy/images/imx7d-pico/core-image-base-imx7d-pico.mender -
tmp/deploy/images/SPL -
tmp/deploy/images/u-boot-dtb.img
The disk image (with .sdimg suffix) is used to provision the device storage for devices without Mender running already. Please proceed to the official documentation on provisioning a new device for steps to do this.
On the other hand, if you already have Mender running on your device and want to deploy a rootfs update using this build, you should use the Mender Artifact files, which have .mender suffix. You can either deploy this Artifact in managed mode with the Mender server (upload it under Releases in the server UI) or by using the Mender client standalone mode.
Flash instructions
Based on the output artifacts described above we need to flash the SPL, u-boot.imx and core-image-base-imx7d-pico.sdimg separately to fully provision an device and for it to work with Mender.
Required software on the host PC:
- imx_usb_loader: GitHub - boundarydevices/imx_usb_loader: USB & UART loader for i.MX5/6/7/8 series
- dfu-util
- libusb
git clone https://github.com/boundarydevices/imx_usb_loader
cd imx_usb_loader && make
Loading U-Boot via USB Serial Download Protocol
Note: This method is convenient for development purposes.
If the eMMC has already a U-Boot flashed with DFU support then
the user can go to step 2 below in order to update U-Boot.
Put pico board in Serial Boot Loader mode (refer to the PICO-iMX7D Quick Start Guide
page 18 (https://www.nxp.com/docs/en/user-guide/PICO-IMX7D-USG.pdf)
Connect a USB to serial adapter between the host PC and pico.
Connect a USB cable between the OTG pico port and the host PC.
Open a terminal program such as minicom.
Copy SPL and u-boot.img to the imx_usb_loader folder.
Load the SPL binary via USB:
$ sudo ./imx_usb SPL
Load the u-boot.img binary via USB:
$ sudo ./imx_usb u-boot-dtb.img
Then U-Boot starts and its messages appear in the console program.
Use the default environment variables:
=> env default -f -a
=> saveenv
Flashing Image into the eMMC
From the u-boot :
=> ums 0 mmc 0
From the host :
sudo dd if=core-image-base-imx7d-pico.sdimg of=/dev/sdX bs=1M ; sudo sync
After flashing use ctrl-c to get out of ums.
Flashing U-Boot into the eMMC
Run the DFU agent so we can flash the new images using dfu-util tool:
=> dfu 0 mmc 0
Flash SPL and u-boot.img into the eMMC running the following commands on a PC:
$ sudo dfu-util -D SPL -a spl
$ sudo dfu-util -D u-boot-dtb.img -a u-boot
The following message should be seen on the U-Boot prompt after a successful upgrade:
#DOWNLOAD … OK
Ctrl+C to exit …
Remove power from the pico board.
Put pico board into normal boot mode.
Power up the board and the new updated U-Boot should boot from eMMC.
References
- The sources of the Yocto integration can be found in meta-mender-community/meta-mender-nxp
If this post was useful to you, please press like, or leave a thank you note to the contributor who put valuable time into this and made it available to you. It will be much appreciated!
, wanderboard is one of the redistributors of the pico pi imx7
