[FAQ] PROCESSOR-SDK-DRA8X-TDA4X: [PSDKRA]Can I use QT & wayland to render VisionApp result?

Posting a response from my colleague Kedar:

To enable disaplay on A72 do the following: 

1. Disable display in R5F/OpenVX, https://software-dl.ti.com/jacinto7/esd/processor-sdk-rtos-jacinto7/latest/exports/docs/vision_apps/docs/user_guide/BUILD_INSTRUCTIONS.html#MAKEFILE_OPTIONS
   #undef ENABLE_DSS, ENABLE_DSS_HDMI , ENABLE_DSS_EDP in ${PSDKRA}/vision_apps/apps/basic_demos/app_tirtos/common/app_cfg_mcu2_0.h, see above link for more details
2. Rebuild vision_apps and update binaries as usual, https://software-dl.ti.com/jacinto7/esd/processor-sdk-rtos-jacinto7/latest/exports/docs/vision_apps/docs/user_guide/BUILD_AND_RUN.html
3. Make sure OpenVX display node is not used in your application (By default vision_apps demos with OpenVX display node, so these should not be used or modified accordingly)
4. Enable display on Linux side by modifying vision_apps dtso as below, remove below lines from arch/arm64/boot/dts/ti/k3-j721e-vision-apps.dtso in linux kernel in PSDKLA. Regenerate the dtbo for the modified dtso and apply it during boot.

5. &serdes_wiz4 {
   
                  status = "disabled";
   
   };
   
   &mhdp {
   
                  status = "disabled";
   
   };
   
   &dss {
   
                  status = "disabled";
   
   };
   
   &main_i2c1 {
   
                  status = "disabled";
   
   };

6. When display is disabled from R5F/OpenVX and enabled in linux kernel via dtbo change above, you should see linux prompt or a splash screen on a wayland display when you boot linux. You can use the usual wayland/DRM APIs to draw to this display.

Regards

Kedar

Brijesh,

Thanks for keep attention. My problem was on D3's RVP board and solved. Linux SYSFS provides simple GPIO control interface. 

DP power can be enabled in RVP by "echo 460 > /sys/class/gpio/export; echo "out" > /sys/class/gpio/gpio460/direction; echo 1 > /sys/class/gpio/gpio460/value".

I guess EVM also can be controlled similarly. 

You can close this post.

Thanks and regards,

Wilson.