Testing the DRM/VSP Interface on RCar G3 Salvator-X platforms
Work which has been completed to repair races between the DU and VSP drivers must be verified by a manual process.
This process involves introducing an artificial delay to simulate the possible delays that could occur in a running system, which would cause an effect on the display pipeline. To implement this delay, a patch: File:DNI-TEST-Fake-long-processing-during-atomic-flush.patch is provided. This patch should be applied manually to your local Linux Kernel sources, before rebuilding.
To manually verify this work - perform the following sequence:
- Establish a build environment for compiling the kernel on your host development platform
- Download the patch and save in your kernel tree.
Establish a baseline comparison
- Apply the patch to your kernel tree without any fixes relating to the issue.
- Compile the kernel, and boot a Salvator-X board
- Introduce an artificial delay with the following command using a shell terminal running on the board:
- # echo 8 > /sys/module/vsp1/parameters/vsp1_delay