Embedded Linux Overview¶

Embedded Linux systems typically consist of four major components.

System Architecture¶

+----------------------+
|   User Applications  |
+----------------------+
|     Root Filesystem  |
+----------------------+
|      Linux Kernel    |
+----------------------+
|      Bootloader      |
+----------------------+
|       Hardware       |
+----------------------+

Bootloader¶

The bootloader initializes the hardware and loads the Linux kernel.

Common bootloaders:

U-Boot
Barebox

Responsibilities:

Initialize DRAM
Load kernel image
Load device tree
Jump to kernel entry point

Linux Kernel¶

The Linux kernel is responsible for:

Process scheduling
Memory management
Device drivers
Network stack
Filesystems

Root Filesystem¶

The root filesystem contains user-space tools and libraries.

Typical structure:

/
├── bin
├── sbin
├── etc
├── lib
├── proc
├── sys
└── dev

Common root filesystem implementations:

BusyBox
Buildroot
Yocto