Newer Pi Linux doesn't do ATAGS by default (cmdline example)

[relistan]

Loving this tutorial! Thanks so much.

If you try to run http://www.cl.cam.ac.uk/projects/raspberrypi/tutorials/os/screen03.html on newer Pi linux builds (replacing kernel.img obviously), it doesn't work. This is not because the code is wrong, it's because newer Linux distributions now use device_tree for kernel configuration which means the bootstrap code doesn't put the configuration at 0x100 formatted as ATAGS. You can fix this by writing this to the end of your config.txt:

# Disable device_tree so we can see the ATAGS
device_tree=

With that setting in place, this code happily runs on my Raspberry Pi Zero W with a Rasbian flash install from a couple of weeks ago, for example.