Device Tree and its roots

Linus Torvalds was sad and mad. ARM was making Linus sad and mad. There were too many cooks, too many ingredients, too many new hardware variations in the world of ARM devices. The architecture had become so popular in the embedded computing world that a thicket of third-party devices were being cooked up to work with ARM. Custom hardware drivers and custom kernels were everywhere. This was making the Linux kernel playground increasingly chaotic.

So, Linus roared: go back to the kitchen, cooks, and make a better recipe! So, they did. Or, so the story goes. Thus was born Device Tree....

For beginners, Device Tree can be a bit difficult to wrap one's head around. However, in order to use BeagleBone Black in more interesting projects, an understanding is often critical. Basically, Device Tree is a data structure to describe the hardware that you add on to your board. With Device Tree, the details of a device are available to the board without needing to be hardcoded...