Provide a description of the U-Boot build process with GCC in the HTML documentation.
Signed-off-by: Heinrich Schuchardt xypron.glpk@gmx.de --- doc/build/gcc.rst | 119 ++++++++++++++++++++++++++++++++++++++++++++ doc/build/index.rst | 1 + 2 files changed, 120 insertions(+) create mode 100644 doc/build/gcc.rst
diff --git a/doc/build/gcc.rst b/doc/build/gcc.rst new file mode 100644 index 0000000000..fcb0b1ffb3 --- /dev/null +++ b/doc/build/gcc.rst @@ -0,0 +1,119 @@ +Building with GCC +================= + +Dependencies +------------ + +For building U-Boot you need a GCC compiler for your host platform. If you +are not building on the target platform you further need a GCC cross compiler. + +Debian based +~~~~~~~~~~~~ + +On Debian based systems the cross compiler packages are named +gcc-<architecture>-linux-gnu. + +You could install GCC and the GCC cross compiler for the ARMv8 architecture with + +.. code-block:: bash + + sudo apt-get gcc gcc-aarch64-linux-gnu + +Depending on the build targets further packages maybe needed + +.. code-block:: bash + + sudo apt-get install bc bison build-essential coccinelle \ + device-tree-compiler dfu-util efitools flex gdisk liblz4-tool \ + libguestfs-tools libncurses-dev libpython3-dev libsdl2-dev libssl-dev \ + lzma-alone openssl python3 python3-coverage python3-pyelftools \ + python3-pytest python3-sphinxcontrib.apidoc python3-sphinx-rtd-theme swig + +Prerequisites +------------- + +For some boards you have to build prerequisite files before you can build +U-Boot, e.g. for the some boards you will need to build the ARM Trusted Firmware +beforehand. Please, refer to the board specific documentation +:doc:`../board/index`. + +Configuration +------------- + +Directory configs/ contains the template configuration files for the maintained +boards following the naming scheme:: + + <board name>_defconfig + +These files have been stripped of default settings. So you cannot use them +directly. Instead their name serves as a make target to generate the actual +configuration file .config. For instance the configuration template for the +Odroid C2 board is called odroid-c2_defconfig. The corresponding .config file +is generated by + +.. code-block:: bash + + make odroid-c2_defconfig + +You can adjust the configuration using + +.. code-block:: bash + + make menuconfig + +Building +-------- + +When cross compiling you will have to specify the prefix of the cross-compiler. +You can either specify the value of the CROSS_COMPILE variable on the make +command line or export it beforehand. + +.. code-block:: bash + + CROSS_COMPILE=<compiler-prefix> make + +Assuming cross compiling on Debian for ARMv8 this would be + +.. code-block:: bash + + CROSS_COMPILE=aarch64-linux-gnu- make + +Build parameters +~~~~~~~~~~~~~~~~ + +A list of available parameters for the make command can be obtained via + +.. code-block:: bash + + make help + +You can speed up compilation by parallelization using the -j parameter, e.g. + +.. code-block:: bash + + CROSS_COMPILE=aarch64-linux-gnu- make -j$(nproc) + +Further important build parameters are + +* O=<dir> - generate all output files in directory <dir>, including .config +* V=1 - verbose build + +Other build targets +~~~~~~~~~~~~~~~~~~~ + +A list of all make targets can be obtained via + +.. code-block:: bash + + make help + +Important ones are + +* clean - remove most generated files but keep the configuration +* mrproper - remove all generated files + config + various backup files + +Installation +------------ + +The process for installing U-Boot on the target device is device specific. +Please, refer to the board specific documentation :doc:`../board/index`. diff --git a/doc/build/index.rst b/doc/build/index.rst index 5051a97e70..5f90f95aca 100644 --- a/doc/build/index.rst +++ b/doc/build/index.rst @@ -7,5 +7,6 @@ Build U-Boot :maxdepth: 2
source + gcc clang tools -- 2.28.0