Getting application-specific data from a device tree

Now we know how to read a device tree file and how to manage it in userspace. In this recipe, we will see how we can extract the configuration settings it holds within the kernel.

Getting ready

To do our job, we can use all the data stored in the DTB to boot our ESPRESSObin and then use the ESPRESSObin as a system test.

As we know, ESPRESSObin's DTS file is stored in kernel sources at linux/arch/arm64/boot/dts/marvell/armada-3720-espressobin.dts or it can be extracted from the running kernel by executing the dtc command as presented in the following code:

# dtc -I fs -o espressobin-reverted.dts /proc/device-tree/

Now let's take this file apart since we can use...