I have bought one zynq-picozed-sdr2-fmc board.
the demo SD card can boot well, and can display iio-oscillator on the hdmi screen.
I want copy one SD card from the demo SD card. copied rootfs using command "sudo cp ./* -dR '/media/gaoming/rootfs'".
the copied sd card can boot well with uboot, and uimage, but the cannot display anything on the hdmi screen.
I do not know why, and only different thing between the demo SD card and copied SD card is copied rootfs, Is there anything wrong?