Install U-Boot to SPI Flash
This step requires Armbian with the legacy kernel. Fedora does not (yet?) expose the SPI node (it’s disabled in the dtb).
Table of contents
Boot Armbian
Boot Armbian, use the u-boot-sunxi-with-spl.bin found in /usr/share/uboot/orangepi_zero/ on the Fedora armhfp image.
sudo apt install -y flashrom
dd if=/dev/zero of=flash.img bs=1M count=2
dd if=u-boot-sunxi-with-spl.bin of=flash.img conv=notrunc
sudo flashrom -p linux_spi:dev=/dev/spidev0.0 -w flash.img -c "MX25L1605D/MX25L1608D/MX25L1673E"
Using the UART cable
The cable must be connected white > green > black, with black closest to the edge of the PCB.
On Windows Subsystem for Linux, run sudo screen /dev/ttyS3 115200. Here ttyS[3] refers to the COM[3] port. Ensure the COM port is set to 115200.