I have a copy of the DisplayPort Reference Design running on my Ultrazed. The reference design itself has AXI GPIO peripherals which interface with the dip switches, LEDs, and push buttons. I am trying to access the registers associated with these peripherals through /dev/mem using busybox. I'm using the base addresses that were set up in the Address Editor as physical addresses for these devices, but I can't seem to access these registers at all. Busybox just ends up hanging, which I guess would indicate that the device is not there. I also might be doing this completely wrong. Is the addresses that we set in the address editor, analogous to the physical memory addresses that we'd normally use to access RAM? It does seem that writes to addresses below 0x80000000 work just fine, which makes sense because the RAM itself is 2GB and lives in this address space.
Any help would be great. Thanks!