[FAQ] TDA4VM: Steps for executing linux DSS on SDK

Note : Please ensure that the DSS module is working fine on the RTOS side (i.e., Please run a vision_apps demo in the RTOS SDK which uses the display)

Please follow the below steps to run the DSS (Display SubSystem) hardware on Linux using tidss driver

Step 1 : Disable all the DSS related macros in ${PSDKRA}/vision_apps/platform/j721e/rtos/common/app_cfg_mcu2_0.h [i.e., ENABLE_DSS_SINGLE or ENABLE_DSS_DUAL (ENABLE_DSS_EDP, ENABLE_DSS_HDMI or ENABLE_DSS_DSI)]

Step 2 : Clean build vision_apps as shown below

cd ${PSDKRA}/
make vision_apps_scrub
make vision_apps -j

Step 3 : Copy the file system into the SD using below command

make linux_fs_install_sd

Step 4 : In the Linux SDK (i.e., PSDKLA), remove the dss related components that are disabled (i.e., serdes_wiz4, mhdp, dss, main_i2c1) , from the file ${PSDKLA}/board-support/linux-5.10.120+gitAUTOINC+95b90aa828-g95b90aa828/arch/arm64/boot/dts/ti/k3-j721e-vision-apps.dts

Step 5 : Build the vision_apps overlay using below command

cd ${PSDKLA}/
make linux-dtbs

Step 6 : Copy the file k3-j721e-vision-apps.dtbo present at ${PSDKLA}/board-support/linux-5.10.120+gitAUTOINC+95b90aa828-g95b90aa828/arch/arm64/boot/dts/ti/ to /media/${USER}/rootfs/boot/ and replace the existing file.

Step 7 : Insert the SD card into the EVM and boot

Step 8 : Before Login, you would see that the display is detected on the monitor.

Step 9 : Login as root and do the below command if the weston service is running

killall weston

Step 10 : In order to display a pattern on the display, you could run the below command

modetest -M tidss -s 39@37:1920x1080

Note : Please check if the port ID is 39 on your device using below command

modetest -M tidss | grep connected

Regards,
Nikhil