OpenAMP Documentation

OpenAMP (Open Asymmetric Multi Processing) is a framework providing software components for developing applications on Asymmetric Multiprocessing (AMP) systems.

Key capabilities include:

• Life Cycle Management and Inter-Processor Communication (IPC) for remote compute resources.
• A standalone library for RTOS and Baremetal environments.
• Compatibility with upstream Linux remoteproc and rpmsg components.
• Support for Linux host/Generic(Baremetal) remote and Generic(Baremetal) host/Linux remote configurations.
• Proxy infrastructure to allow Baremetal remote contexts to perform file operations (e.g., printf, scanf, open, close, read, write) via the host.

The OpenAMP library libopen_amp is organized into the following directories within lib/:

• virtio/: Virtio implementation.
• rpmsg/: RPMsg implementation.
• remoteproc/: Remoteproc implementation.
• proxy/: Implementation for accessing a device on another processor using file operations.

Note: System and machine support has been moved to the libmetal library.

To build OpenAMP for communication between Linux processes, follow these steps:

1. Install required packages:

   sudo apt-get install libsysfs-dev libhugetlbfs-dev

2. Build libmetal:

   mkdir -p build-libmetal
   cd build-libmetal
   cmake <libmetal_source>
   make VERBOSE=1 DESTDIR=<libmetal_install> install

3. Build OpenAMP:

   mkdir -p build-openamp
   cd build-openamp
   cmake <openamp_source> -DCMAKE_INCLUDE_PATH=<libmetal_built_include_dir> \
               -DCMAKE_LIBRARY_PATH=<libmetal_built_lib_dir>
   make VERBOSE=1 DESTDIR=$(pwd) install

After installation, headers are located in build/usr/local/include and libraries in build/usr/local/lib.

OpenAMP relies on libmetal for hardware abstraction. To port OpenAMP to a new system, you must implement the following libmetal APIs in your system's directory (lib/system/<SYS>):

• alloc: Memory allocation and free.
• cache: Cache flushing and invalidation.
• io: Memory mapping (required for accessing vrings and carved-out memory).
• irq: IRQ handler registration, IRQ disable/enable, and global IRQ handling.
• mutex: Mutex implementation.
• shmem: Shared memory (for RTOS, lib/system/generic/ can often be used).
• sleep: Microsecond sleep (used when failing to acquire a buffer).
• time: Timestamping.
• init: Library initialization.
• atomic: Atomic operations.

If using a compiler other than GNU gcc, you must port libmetal for your compiler. OpenAMP specifically requires the atomic operations defined in lib/compiler/gcc/atomic.h.

The Zephyr implementation of OpenAMP is a fork of this repository with add-ons for Zephyr integration.

To compile OpenAMP for a Zephyr project, use the Zephyr build environment. Refer to the Zephyr OpenAMP samples for examples and Zephyr documentation for the build process.