Switching FSBL Targeting Processor The FSBL in platform is created for Cortex-A53, by default, on a Zynq UltraScale+ MPSoC device. You can re-target it to Cortex-R5F when necessary. Double click platform.spr. Select psu_cortexa53_0 > zynqmp_fsbl. Click Re-target to psu_cortexr5_0. Click on the hammer icon to build the platform.