Source code directories

Typically, the startup source code is found in the following directory:

bsp_working_dir/src/hardware/startup/boards/boardname

The diagram shows only the directories you should always find in the startup source code directory tree. Note the following about this directory tree:

hardware/

• The only directory that will always be found under hardware is startup.

• The hardware directory will usually also include the ipl directory, but on systems that always use U-Boot, this directory may be absent because it isn't needed.

  Similarly, the flash directory will be present only if the system will use a Flash filesystem.

• In most cases, the hardware directory also includes other subdirectories such as dev* directories for device drivers (e.g., audio, eMMC), and spi and i2c directories with the source code that supports these technologies.

boards/

The boards directory has platform-specific source code:

• It has a subdirectory for the specific board type (e.g., imx6x), which has the board-specific startup API source code, and subdirectories (e.g., mini-can, sabreARD) with even more source API files to support specific board variants and specific technologies.
• The buildfile is in one of these directories (e.g., src/hardware/boards/imx6x/sabreARD/build).

lib/

The lib directory has the generic (i.e., common to all platforms) startup API source files, and:

• an architecture-specific subdirectory (e.g., arm, x86_64) with the startup API source for the current board architecture.
• a public subdirectory, with header files.