I started working with the HDMI Video output on ZC702 design(http://wiki.analog.com/resources/tools-software/linux-drivers/platforms/zynq) using Xilinx Linux kernel, and I have some questions to ask.
1. The Linux kernel for ADI design uses i2c-gpio driver instead of i2c-xilinx driver. With i2c-gpio, I was having trouble to probe/initialize i2c-mux(pca9548) in the device driver(pca954x). On the other hand, It works ok with i2c-xilinx except the i2c write timeout that happens once in a while. Is this something you observed? or did you have any other reason to switch to i2c-gpio from i2c-xilinx?
2. I tested drm KMS functions of this design using the simple test cases from libdrm. I wonder if you find any other KMS test cases useful, before moving on to run X server or any other display managers.