Introduction

• Raspberry Pi Official 7" lcd screen display will be working . The 7" touch screen monitor for Raspberry Pi gives users the ability to create all-in-one, integrated projects such as tablets, infotainment systems and embedded projects. 

• The 800x480 display connects via an adapter board which handles power and signal conversion. 

•  We can plug keyboard and mouse to the raspberrypi for the userinteraction. 

• Screen resolution 800 x 480 pixels Connects to the Raspberry Pi board using a ribbon cable connected to the DSI port. 

• Adapter board is used to power the display and convert the parallel signals from the display to the serial (DSI) port on the Raspberry Pi. 

• The display works with all existing Raspberry Pi models with RDK images.

Implementation details

  Containers layer - meta-rdk-containers:    

•     Consists of main container image(rdk-generic-hybrid-lxc-image).
•     Latest "lxc-container-generator" has been added for container generation at do_rootfs stage.
•     Distro feature and latest lxc version updated in qemux86hybsecure.conf.

  Emulator layer - meta-rdk-bsp-emulator:

•        Added emulator specific package groups and plugins to the container image.

  New Container generation process:

     This subsection describes how the new container generation process is replacing the earlier process.

•       In this process containers will be generated using  "lxc-container-generator"  recipe, which will use corresponding .xml files to generate containers.
•       All  dependencies(such as required binaries,libraries,script files) will be provided in each container .XML file.
•       For permissions of files  "add-users-groups-file-owners-and-permissions.inc" file has been added.
•       At rootfs stage containers will be generated in /container path of rootfs.
•       Each container will consists of corresponding script (.sh) file for launching that particular container.
•       Every process will be launched from corresponding component service file. Single (or) multiple processes can be launched/attached to container.

  XML and conf files:

•     All required XML and configuration files are placed along with lxc-container-generator recipe in meta-rdk-bsp-emulator layer.

  Service files:     

•   In platformcontrol container: 

                 Three service files added for launching corresponding processes inside container (sysmgr.service, irmgr.service and dsmgr.service) .        

•   In rmfstreamer container:

                 rmfstreamer.service file has been added.

•   In rdkbrowser2 container:

                 rdkbrowser2.service file has been added.

Implemented containers

 Platformcontrol

• runs sysmgr,irmgr and dsmgr processes inside container.
• sysmgr will be launched in new container using lxc-execute.
• irmgr and dsmgr processes has been attached to same container using lxc-attach.

 Rmfstreamer

•  runs rmfstreamer inside container.
•  rmfstreamer will be launched in new container using lxc-execute.

 Rdkbrowser2

•  runs rdkbrowser2 browser application inside container.
•  westeros will be launched in new container using lxc-execute.
•  rdkbrowser2 will be attached to the same container using lxc-attach.
  

       Note: As we are in the plan of bringing APPmanager as default application we are not running rdkbrowser2 service file on boot-up.

Building procedure

•     repo init -u https://code.rdkcentral.com/r/manifests -b rdk-next -m rdkv-asp-extsrc.xml
•     repo sync --no-tags
•     source meta-cmf-bsp-emulator/setup-environment
•     meta-rdk-containers/conf/machine/qemux86hybsecure.conf
•     bitbake rdk-generic-hybrid-lxc-image

Container verification

•     pstree can be used to track the list of containers running as below.

•      ps -Af | grep lxc also lists the current running containers.
       
  

DEBUG Logs

• strace can give more debug information about containers:

          Example:
          strace -f -o lxc-execute.log /usr/bin/lxc-attach -n PLATFORMCONTROL -f /container/PLATFORMCONTROL/conf/lxc.conf

          -u 704 -g 704  -- /usr/bin/dsMgrMain

• lxc-execute.log for debugging purpose.

Test cases

•    RMFAPP can be used to verify rmfstreamer container. 
     Example: play  http://192.168.2.68:8080/vldms/tuner?ocap_locator=ocap://0x125d
•    RDKBROWSER2 can be used to launch any URL.
     Example: systemctl enable rdkbrowser2.service 
                     systemctl start rdkbrowser2.service - user can see the webpage in rdkbrowser2.
  
     If user wants to change URL, then we need to enter into this container and need to change rdkbrowser2.sh binary  as below:
     systemctl stop rdkbrowser2.service
     systemctl stop westeros-setup.service\
     use command:
     /usr/bin/lxc-execute -n RDKBROWSER2    -f /container/RDKBROWSER2/conf/lxc.conf – /bin/sh
     and then change url in /usr/bin/rdkbrowser2.sh file inside this container environment.

Reference

• https://cloud.google.com/containers/
• https://www.cio.com/article/2924995/software/what-are-containers-and-why-do-you-need-them.html
• https://linuxcontainers.org/
• https://help.ubuntu.com/lts/serverguide/lxc.html
• https://linuxcontainers.org/lxc/documentation/