GPU

General Info

It’s possible to create a memory buffer in GPU for the frames in st20 protocol. This is done by using gpu direct library.

Refer to gpu direct s20 pipeline to see an example.

Build MTL GPU-Direct Library

Use Meson to build the GPU-Direct library specifically.

cd <mtl>/gpu_direct
meson setup build
sudo meson install -C build

# check package installed
pkg-config --libs mtl_gpu_direct

# build the mtl library
./build.sh

Run TX Sample App

Prepare a file (test.yuv) of 1920x1080 UYVY frames to send. You can refer to run guide for more details.

./build/app/GpuDirectVideoTxMultiSample 192.168.99.110 20000 test.yuv

Run RX Sample App

You need the SDL library to display the received frame.

./build/app/GpuDirectVideoRxMultiSample 192.168.99.111 192.168.99.110 20000

How to enable it in MTL

Currently, only the ST20P receive frame mode supports VRAM frame allocation.

To enable this feature, use the following flag while initializing the session:
ST20P_RX_FLAG_USE_GPU_DIRECT_FRAMEBUFFERS

This setting instructs MTL to allocate frames directly in VRAM.

Additionally, you must initialize the GPU device in your application using gpu direct library by init_gpu_device function.

Pass the address of the device with the gpu_context parameter:
gpu_context to the st20p rx flags during session initialization.

Warning: Direct memory access functionality is disabled when using this flag. Memory allocated in VRAM cannot be accessed directly using DPDK API.