Introduction: Build Target AGL image with Yocto project

To setup AGL on a raspberrypi or any target system, first we need build an AGL image particular to that system/chip. For this we will use Yocto project to build the target AGL image.

Steps that we will following

• Setup an EC2 machine and build environment
• Download the software
• Build the image
• Copy the AGL image from EC2 instance to your local machine
• Format the SD card
• Copy the AGL image from your local instance to SD card.
• BootUp

Step 1: Setup an EC2 instance

• To create an AGL image, we need a linux instance. This instance will be used as a host system.
• Choose an instance that has more cpu power as it will help to create the AGL image faster.
• In my case, i chose g3.8xlarge ec2 instance with ubuntu as operating system. Once the instance is created, login to the instance.
• Use the below command to install the packages

sudo apt-get update
sudo apt-get install curl gawk wget git diffstat unzip texinfo gcc-multilib build-essential chrpath socat cpio python python3 python3-pip python3-pexpect python-dev xz-utils debianutils iputils-ping cpu-checker default-jre parted

Step 2: Download AGL source code

• Setup the build environment

export AGL_TOP=$HOME/workspace_agl
mkdir -p $AGL_TOP

• Setup and Prepare Repo Tool

AGL uses **repo** tool for managing repos.

mkdir -p ~/bin
export PATH=~/bin:$PATH
curl https://storage.googleapis.com/git-repo-downloads/repo > ~/bin/repo
chmod a+x ~/bin/repo

• Download the latest AGL source code. Note that raspberrypi4 option is only in this latest version.

cd $AGL_TOP
repo init -u https://gerrit.automotivelinux.org/gerrit/AGL/AGL-repo
repo sync

tree -L 1

Step 3: Build the AGL platform for Raspberry Pi

• Here we will build the AGL demo platform for raspberry pi 4.

• "-m" option sets the machine/architecture/board that we are going to use. In this case, it will be raspberrypi4

• At the time of writing this, the available machines in the LATEST release are below.

Available machines:
   [meta-agl]
       bbe
       beaglebone
       cubox-i
       cyclone5
       dra7xx-evm
       dragonboard-410c
       dragonboard-820c
       ebisu
       h3-salvator-x
       h3ulcb
       h3ulcb-kf
       h3ulcb-nogfx
       hsdk
       imx6qdlsabreauto
       imx8mqevk
       imx8mqevk-viv
       intel-corei7-64
       m3-salvator-x
       m3ulcb
       m3ulcb-kf
       m3ulcb-nogfx
       nitrogen6x
       qemuarm
       qemuarm64
     * qemux86-64
       raspberrypi3
       raspberrypi4

• Build the image with feature: agl-all-features for machine: raspberrypi4
• This execution will take 45 mins to 1 hour to complete.

source meta-agl/scripts/aglsetup.sh -m raspberrypi4 agl-all-features

bitbake agl-demo-platform

• The image will be stored in the below path under $AGL_TOP directory.

cd build/tmp/deploy/images/raspberrypi4-64/
ls agl-demo-platform-raspberrypi4-64-20200820181620.rootfs.wic.xz
cp agl-demo-platform-raspberrypi4-64-20200820181620.rootfs.wic.xz/tmp/

Step 4: Copy the AGL image from EC2 instance to your local machine.

• On your local machine/mac home directory

cd ~
scp -i ~/work/amazon/xxxxx.pem [email protected]:/tmp/agl-demo-platform-raspberrypi4-64-20200820181620.rootfs.wic.xz .

Step 5: Format the SD card

• Use USB drive reader to connect to your micro SD card to the mac/laptop.
• Open Disk Util app on your mac.
• Notedown the Device
• Click on Erase to delete all the previous contents from the SD card. MAKE SURE YOU SELECTED THE APPROPRIATE DRIVE
• Click on UnMount button as well. IN THE PICTURE, IT SHOWS - MOUNT, BUT YOU WILL SEE THE UNMOUNT BUTTON AFTER ERASING THE OLD CONTENT

Step 6: Copy the AGL image from your local instance to SD card.

• Use the dd command to copy the contents.

cd ~
xzcat agl-demo-platform-raspberrypi4-64-20200820181620.rootfs.wic.xz | sudo dd of=/dev/disk2 bs=4m

Step 7: Bootup the Raspberrypi

• Connect Mouse, Keyboard to the Raspberrypi 4
• Connect to the monitor using micro HDMI to HDMI cable.
• Powerup the Raspberry pi.
• You will see the picture on your monitor as below. By default the screen orientataion horizontally.

Step 8: Login to Shell

• To connect to shell, from the online research i found 2 ways
• 1st One is using the USB Serial Cable. - I did not try this.
• 2nd option which i tried is below.

* Connected an ethernet cable to raspberry pi.
* And manually looked my router UI to find out the raspberry pi IP address. See the picture below.
* In my case, my internet provider is AT&T, and their default IP address to connect to router is:  **http://192.168.1.254/**
* Make sure you are disconnected from your VPN, if you have any.
* Once I login, i followed the below steps.

• In this page, you will see an entry for raspberrypi-4 and you can get the IP address. You can also see the associated name for that.

• Login ssh command is. No password is needed.

ssh root@<IP-Address>

• In my case, By default raspberry pi host is set to raspberrypi4-64. You can also try this machine to connect.

ssh root@raspberrypi4-64