I have a custom board with Zynq-7020 device on it. It has 512MB DDR3, 32MB FLASH memory on board but SD card interface is not routed. I have several FPGA pins available to implement 1bit SD interface through EMIO. My idea is to run FSBL → u-boot → kernel from FLASH memory and load PYNQ rootfs from SD card through EMIO SD interface.
I know that PYNQ does not load bitstream on bootup (I already know solution for this). My question is if it is possible to run PYNQ image like this and what will happen when loading PYNQ overlay (if overlay will also have EMIO SD interface)? Will this work? What special care must be taken?