Directory hierarchy

Directory path

Usage

/arch

Architecture-specific files

/arch/arc

Files relating to ARC architecture

/arch/arm

Files relating to ARM architecture

/arch/m68k

Files relating to m68k architecture

/arch/microblaze

Files relating to microblaze architecture

/arch/mips

Files relating to MIPS architecture

/arch/nios2

Files relating to Altera NIOS2 architecture

/arch/powerpc

Files relating to PowerPC architecture

/arch/riscv

Files relating to RISC-V architecture

/arch/sandbox

Files relating to HW-independent “sandbox”

/arch/sh

Files relating to SH architecture

/arch/x86

Files relating to x86 architecture

/arch/xtensa

Files relating to Xtensa architecture

/api

Machine/arch-independent API for external apps

/board

Board-dependent files

/boot

Support for images and booting

/cmd

U-Boot commands functions

/common

Misc architecture-independent functions

/configs

Board default configuration files

/disk

Code for disk drive partition handling

/doc

Documentation (a mix of ReST and READMEs)

/drivers

Device drivers

/dts

Makefile for building internal U-Boot fdt.

/env

Environment support

/examples

Example code for standalone applications, etc.

/fs

Filesystem code (cramfs, ext2, jffs2, etc.)

/include

Header Files

/lib

Library routines relating to all architectures

/Licenses

Various license files

/net

Networking code

/post

Power On Self Test

/scripts

Various build scripts and Makefiles

/test

Various unit test files

/tools

Tools to build and sign FIT images, etc.