Do something like this to get the latest firmware and DTBs:
```
firmware_commit=master
files="bootcode.bin fixup.dat start.elf fixup_cd.dat start_cd.elf bcm2708-rpi-b.dtb bcm2708-rpi-b-plus.dtb bcm2709-rpi-2-b.dtb bcm2710-rpi-3-b.dtb overlays/pi3-disable-bt.dtbo overlays/mmc.dtbo"
mkdir fat/overlays
for f in $files
do
fetch -o "fat/$f" "https://raw.githubusercontent.com/raspberrypi/firmware/$firmware_commit/boot/$f"
done
```
Copy kernel.bin to kernel7.img on the fat partition for RPI2/3, or kernel.img for a RPI0/1.
Write this in config.txt:
```
dtparam=audio=on,i2c_arm=on,spi=on,random=on
dtoverlay=mmc
dtoverlay=pi3-disable-bt
kernel_address=0x200000
```
Boot your PI.