I didn't think I would go here, but I always do on every ARM based project at some point. U-boot code can been tough to navigate, but it often has extremely helpful code examples.
My interest started when I had questions related to writing some bare metal code to download bitstreams into the Zynq PL using the devcfg registers and the PCAP.
I interrupted the boot on my Ebaz board and looked at U-boot help, and by golly there is an fpga command.
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