DTB

DTB commonly refers to the Device Tree Blob, a binary data structure used by some operating systems to describe the hardware present in a system. It allows the kernel to understand CPUs, memory, buses, peripherals, and their configurations without relying on board-specific source code. This enables greater portability across devices and simplifies kernel maintenance.

A DTB is produced from a human-readable device tree source file (.dts) by the Device Tree Compiler (dtc). During boot, the kernel can load the DTB in several ways: it may be embedded in the kernel image, supplied by the bootloader, or loaded from an adjacent file on the system. On many architectures, including ARM and ARM64, the boot process can also apply device tree overlays to modify or extend the hardware description at runtime, without rebuilding the kernel.

Key concepts associated with the DTB include bindings, which describe how a hardware component should be represented in the tree, and the use of phandles and compatible strings to match devices with appropriate drivers. The DTB supports dynamic hardware configurations through overlays, enabling changes to hardware descriptions as needed for different boards or revisions.

The Device Tree approach originated in embedded Linux to improve portability across boards and reduce platform-specific kernel code. While widely used in various architectures, the DTB is most commonly associated with Linux-based embedded systems, though similar tree-based hardware descriptions have appeared in other ecosystems.

DTB can stand for other terms in different contexts, but in computing it most often denotes Device Tree Blob. Context usually clarifies which meaning applies.