eglInitialize fails with DRM KMS

Autonomous Machines Jetson & Embedded Systems Jetson AGX Xavier
1

Hi, I’m trying to port an existing application to the Jetson Xavier AGX. It currently works in KMS mode. First I tried using tegra-ugm:

# Stop X xerver
sudo service gdm stop; 
sudo ln -sf /usr/lib/aarch64-linux-gnu/tegra/libnvgbm.so /usr/lib/aarch64-linux-gnu/libgbm.so.1
sudo modprobe tegra-udrm modeset=1

I am able to open the gdm device, but eglInitialize fails. I also tried the method with drmOpen (which is what nvrenderer.cpp uses), but eglInitialize fails on that as well.

3

Hi,
Please refer to steps in
https://docs.nvidia.com/jetson/l4t/#page/Tegra%20Linux%20Driver%20Package%20Development%20Guide/accelerated_gstreamer.html#wwpID0E02P0HA

If you don’t run Westson, the commands are not required:

$ sudo ln -sf /usr/lib/aarch64-linux-gnu/tegra/libnvgbm.so /usr/lib/aarch64-linux-gnu/libgbm.so.1
$ sudo modprobe tegra-udrm modeset=1
4

I’m unsure if the steps are related. For example I’m trying to run kmscube (Debian -- Details of package kmscube in buster) which fails even with those commands.

5

Hi,
Please check if you can run

/usr/src/jetson_multimedia_api/samples/08_video_dec_drm

Jetson Linux API Reference: 08_video_dec_drm (Direct Rendering Manager) | NVIDIA Docs

This is the DRM sample we verify in each release. Suggest you give it a try and develop your usecase based on it.

6

Ok, so it sounds like using EGL+drm just isn’t supported? I’ve seen that sample and it doesn’t address my issue as the sample doesn’t use EGL.

7

Hi,
Not sure if EGL APIs work, but the following demo code works:

    if (ctx->enable_cuda)
    {
        /* Create EGLImage from dmabuf fd */
        ctx->egl_image = NvEGLImageFromFd(ctx->egl_display, fd);
        if (ctx->egl_image == NULL)
            ERROR_RETURN("Failed to map dmabuf fd (0x%X) to EGLImage",
                    ctx->render_dmabuf_fd);

        /* Pass this buffer hooked on this egl_image to CUDA for
           CUDA processing - draw a rectangle on the frame */
        HandleEGLImage(&ctx->egl_image);

        /* Destroy EGLImage */
        NvDestroyEGLImage(ctx->egl_display, ctx->egl_image);
        ctx->egl_image = NULL;
    }

Doing CUDA post processing should work fine.

9