rw1nkler / alkali-csd-fw

Alkali Firmware

This repository contains firmware sources of the Alkali project, which can be used to generate the bitstream for the Western Digital NVMe accelerator test platform (AN300 board). The project includes Linux built with Buildroot that contains application for APU and there is a separate Zephyrproject application for RPU.

The register description headers are auto-generated from the NVMe documentation. It is used by RPU application to communicate with NVMe control registers.

Repository structure

The diagram below presents the simplified structure of this repository and includes the most important files and directories.

.
├── apu-app
│   ├── CMakeLists.txt
│   ├── src
│   │   ├── cmds
│   │   ├── vm
│   │   ├── vta
│   │   └── ...
│   └── third-party -> ../third-party
├── br2-external
│   ├── board
│   │   └── an300
│   │       └── ...
│   ├── configs
│   │   └── zynqmp_nvme_defconfig
├── LICENSE
├── Makefile
├── README.md
├── requirements.txt
├── rpu-app
│   ├── CMakeLists.txt
│   ├── nvme.overlay
│   ├── prj.conf
│   ├── rpu.tcl
│   ├── src
│   │   └── ...
│   └── west.yml
└── third-party (submodules)
    ├── buildroot
    ├── googletest
    ├── linux
    ├── registers-generator
    ├── tensorflow
    └── ubpf

• apu-app/ - contains source files for APU Application. The APU App will be responsible for processing the custom NVMe commands. It is generated with use of Buildroot.

• br2-external/ - configuration files for Buildroot to build the Linux system for APU. Its rootfs contains an APU Application.

• rpu-app/ - contains source file for RPU Application. The RPU software is responsible for handling the functionality required by the NVMe standard including regular read/write transactions. Application is built using Zephyr RTOS as an operating system.

• third-party/ - the directory used to store all external projects used as a part of the alkali-csd-hw project. The register-generator directory contains scripts used to parse the NVMe specification and generate the headers with registers descriptions. The buildroot, googletest, tensorflow and ubpf are used to build APU software, including an operating system and applications.

• Makefile - file containing all the rules used to manage the repository. Type make help to display all the documented rules that can be used inside the project.

Prerequisites

This repository contains the fw.dockerfile which can be used to simplify the process of installing dependencies. Before running other rules from this repository make sure that you build the docker image by using:

make docker

In case you want to install all the prerequisites directly on your machine, follow the instructions from the fw.dockerfile.

Usage

If you use docker workflow, use make enter to open the docker container before running other commands.

To generate software for the alkali board you can simply use:

make all

This will run all builds one by one in order APU App, Linux system, RPU App. However it might take a lot of time (~2 hours) so you can also choose which part would you like to build. Note that in order to build Linux system, you must build an APU App first.

• Build APU App:

make apu-app

• Build Linux system:

make buildroot

• Build RPU App:

make rpu-app

The final output files can be found in build/ directory.

Managing Subprojects

The projects available in this repository use different build systems which are all together managed by the main Makefile. To extend the existing project with add new files one has to understand how they are organized.

• apu-app uses CMake to manage its dependencies. To add sources to the project, include the new files in the proper list of either library or executable targets inside the apu-app/CMakeLists.txt file. For details about the CMake file format check CMake documentation

• rpu-app uses west and CMake to manage its dependencies. To add sources to the application extend the list of [target_sources (https://cmake.org/cmake/help/latest/command/target_sources.html) in the rpu-app/CMakeLists.txt. For details about the CMake file format check CMake documentation All the changes related to the device tree settings should be applied to rpu-app/nvme.overlay file. The list of the Zephyr subprojects used to build the app is managed by west and is contained in the rpu-app/west.yml file. For details about the West check West documentation

• Buildroot uses make and Kconfig for building the projects with the given configuration. The most important part of the project includes the configuration located in the br2-external/configs/zynqmp_nvme_defconfig which is used to select all the components of the system including U-Boot, Linux kernel, ARM trusted firmware, and root file system. Besides the packages specified in the config, all the files from the br2-external/board/alkali directory are copied to the final root file system. Details about the Buildroot may be found in the Buildroot's documentation