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How to compile Linux with Qt5 option using Yocto for LICHEE PI ZERO

Instruction how to build an image for Lichee Pi Zero and Lichee Pi Zero Dock in Yocto

Products:

Lichee Pi Zero Version

Schematic

Lichee Pi Zero Dock Version

Schematic

General Note:

Assumed that Linux Ubuntu is installed

List of tested elements

WiFi
Ethernet
Lcd
Touchscreen
Led
Backlight for Lcd

List of not tested elements

Bluetooth – appears during system boot up
Microphone
Headphone

How to build images

  1. First, make sure to following packages are installed in the system
sudo apt-get install gawk wget diffstat unzip texinfo gcc-multilib build-essential chrpath socat libsdl1.2-dev xterm libgmp3-dev libmpc-dev

Note: More information can be found on the Yocto reference manual.

2. Download necessary Yocto packaged listed below. Be sure to be in the root of the home folder.

mkdir yocto 
cd yocto 
mkdir build 
git clone git://git.yoctoproject.org/poky --depth 1 -b dunfell
cd poky 
git clone git://git.openembedded.org/meta-openembedded --depth 1 -b dunfell
git clone https://github.com/meta-qt5/meta-qt5.git --depth 1 -b dunfell
git clone https://github.com/voloviq/meta-licheepizero --depth 1 -b dunfell

3. Select directory to build Linux

Zero version
source oe-init-build-env ~/yocto/build/licheepizero
Zero Dock version
source oe-init-build-env ~/yocto/build/licheepizero-dock

4. Modify bblayers.conf(located in ~/yocto/build/licheepizero/conf(or licheepizero-dock/conf))

BBLAYERS ?= " \
${HOME}/yocto/poky/meta \
${HOME}/yocto/poky/meta-poky \
${HOME}/yocto/poky/meta-openembedded/meta-oe \
${HOME}/yocto/poky/meta-openembedded/meta-networking \
${HOME}/yocto/poky/meta-openembedded/meta-python \
${HOME}/yocto/poky/meta-qt5 \
${HOME}/yocto/poky/meta-licheepizero \
"

Note: Please adapt PATH of conf/bblayers.conf if necessary.

5. Modify or align following elements in local.conf(located in ~/yocto/build/licheepizero/conf(or licheepizero-dock/conf)) file

MACHINE ??= "licheepizero-dock"
or 
MACHINE ??= "licheepizero"
DL_DIR = "${HOME}/yocto/downloads"
SSTATE_DIR = "${HOME}/yocto/sstate-cache"
TMPDIR = "${HOME}/yocto/tmp"
at the end add some option if necessary 
RM_OLD_IMAGE = "1" 
INHERIT += "rm_work"

Note: Please adapt rest of conf/local.conf parameters if necessary.

6. Build objects

Issue from console one of the following option

console image 
bitbake console-image

sato (X11) image 
bitbake sato-core-image

qt5 image 
bitbake qt5-image

qt5 toolchain sdk 
bitbake meta-toolchain-qt5

7. After compilation images appear in

Zero version
~/yocto/tmp/deploy/images/licheepizero
Zero Dock version
~/yocto/tmp/deploy/images/licheepizero-dock

8. Insert SD CARD into dedicated CARD slot and issue the following command to write an image

Note:
Be 100% sure to provide a valid device name (of=/dev/sde). Wrong name “/dev/sde” damage Your system file !

Zero version
sudo dd if=~/yocto/tmp/deploy/images/licheepizero/qt5-image-licheepizero.sunxi-sdimg of=/dev/sde bs=1024
Zero Dock verison
sudo dd if=~/yocto/tmp/deploy/images/licheepizero-dock/qt5-image-licheepizero-dock.sunxi-sdimg of=/dev/sde bs=1024

Limitation

rootfs-resize not working (SD CARD size can be resized manualy)
no wiringpi or similar library to control GPIO in C code
discover problem when WiFi connected to access point (probably some drivers issues), nevertheless WiFi works




Lucjan Bryndza

Embedded software engineer