This repository hosts a modified version of Xilinx's Zynq UltraScale+ FPGA driver, part of the FRED Framework software stack. The driver has been extended for supporting I/O multiplexing and the direct load of contiguous bitstream images for userspace. These new functionalities are implemented through four sysfs attributes. The first two attributes are used for passing a reference to a contiguous bitstream image to the driver. The third attribute is used for starting the reconfiguration. Once the reconfiguration is started, the fourth attribute can be monitored through poll() or epoll() syscalls to receive a notification when the reconfiguration is completed. Please note that this driver is intended to be used only for testing and scientific purposes.