top: Rename LICENSE file to COPYING.BSD

Also make sure that this file contains only the official BSD 2-clause
license text, nothing else.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
1 file changed
tree: fe3fa9092a6723576a03c0579122e5ee4078b71a
  1. .gitignore
  2. COPYING.BSD
  3. Makefile
  4. README.md
  5. docs/
  6. firmware/
  7. include/
  8. lib/
  9. platform/
README.md

RISC-V Open Source Supervisor Binary Interface (OpenSBI)

The RISC-V Supervisor Binary Interface (SBI) is a recommended interface between:

  1. A platform specific firmware (M-mode) and a general purpose OS or hypervisor or bootloader (S-mode or HS-mode).
  2. A hypervisor (HS-mode) and a general purpose OS or bootloader (VS-mode)

The RISC-V SBI specification is maintained as an independent project by the RISC-V Foundation in Github

OpenSBI aims to provides an open-source and extensible implementation of the RISC-V SBI specification for case 1 mentioned above. OpenSBI implementation can be easily extended by RISC-V platform or System-on-Chip vendors to fit a particular hardware configuration.

OpenSBI provides three components:

  1. libsbi.a - A generic OpenSBI static library
  2. libplatsbi.a - Platform specific OpenSBI static library, that is, libsbi.a plus platform specific hooks
  3. firmwares - Platform specific bootable firmware binaries

Building and Installing generic libsbi.a

For cross-compiling, the environment variable CROSS_COMPILE must be defined to specify the toolchain executable name prefix, e.g. riscv64-unknown-elf- if the gcc executable used is riscv64-unknown-elf-gcc.

To build the generic OpenSBI library libsbi.a, simply execute:

make

All compiled binaries will be placed in the build directory. To specify an alternate build directory target, run:

make O=<build_directory>

To generate files to be installed for using libsbi.a in other projects, run:

make install

This will create the install directory with all necessary include files and binary files under it. To specify an alternate installation directory, run:

make I=<install_directory> install

Building and Installing platform specific libsbi.a and firmwares

The libplatsbi.a and firmware files are only built if the PLATFORM=<platform_subdir> argument is specified on make command lines. <platform_subdir> must specify the path to one of the leaf directories under the platform directory. For example, to compile the library and firmware for QEMU RISC-V virt machine, <platform_subdir> should be qemu/virt.

To build libsbi, libplatsbi, and firmwares for a specific platform, run:

make PLATFORM=<platform_subdir>
or
make PLATFORM=<platform_subdir> O=<build_directory>

To install libsbi, headers, libplatsbi, and firmwares, run:

make PLATFORM=<platform_subdir> install
or
make PLATFORM=<platform_subdir> I=<install_directory> install

In addition, platform specific make command-line options to top-level make , such as PLATFORM_ or FW_ can also be specified. These options are described under docs/platform/<platform_name>.md and docs/firmware/<firmware_name>.md.

License

The software is provided under a BSD-2-Clause license. Contributions to this project are accepted under the same license with developer sign-off as described in the Contributing Guidelines.

This project also contains code from other projects as listed below. The original license text is included in those source files.

  1. The libfdt source code is disjunctively dual licensed (GPL-2.0+ OR BSD-2-Clause). It is used by this project under the terms of the BSD-2-Clause license. Any contributions to this code must be made under the terms of both licenses.

Documentation

A more detailed documentation is under the docs directory and organized as follows.

  • docs/contributing.md - Guidelines for contributing to OpenSBI project
  • docs/platform_guide.md - Guidelines for adding new platform support
  • docs/library_usage.md - Guidelines for using the static library
  • docs/platform/<platform_name>.md - Documentation for the platform <platform_name>
  • docs/firmware/<firmware_name>.md - Documentation for the firmware <firmware_name>

The source code is also well documented. For source level documentation, doxygen style is used. Please refer to Doxygen manual for details on this format.

The Doxygen can be installed on your debian build system using following:

sudo apt-get install doxygen doxygen-latex doxygen-doc doxygen-gui graphviz

To build a consolidated refman.pdf of all documentation, run:

make docs
or
make O=<build_directory> docs

NOTE: refman.pdf will be available under <build_directory>/docs/latex.

To install a consolidated refman.pdf of all documentation, run:

make install_docs
or
make I=<install_directory> install_docs

NOTE: refman.pdf will be installed under <install_directory>/docs.