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For Petalinux related limitations please refer PetaLinux 2020.1 - Product Update Release Notes and Known Issues
For VCU related limitations please refer AR# 66763: LogiCORE H.264/H.265 Video Codec Unit (VCU) - Release Notes and Known Issues, Xilinx Zynq UltraScale+ MPSoC Video Codec Unit and PG252 Link will be added <June-05> link.
xdma driver can transfer max up to 512K chunk size of data.
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