The Zynq board support packages (BSP) contain:
Pre-Built SD Card Images
Allows the user to power up the system out the box.
The Vivado project contains the processing system (PS) configuration, which is required by the First Stage Boot Loader.
First Stage Boot Loader
The First Stage Boot Loader configures the processor with the settings from Vivado before loading U-Boot.
Second Stage Boot Loader
To make it easier to develop and update Embedded Linux images, the First Stage Boot Loader loads the second stage Boot Loader. The Second Stage Boot Loader allows a number of boot options, including booting from QSPI, EMMC, SD card, and TFTP.
PDF documents containing instructions on developing both hardware and software designs for the Zynq boards.
ADM-VPX3-9Z2 download BSP from here (github).