Experiments in bare metal code.

RISC-V is the only architecture currently implemented.

Building

The preferred toolchain is the Sifive GNU embedded toolchain from https://www.sifive.com/software

Tested with CMake 3.21, might still work with 3.19 but not tested anymore.

cd desideria
cmake -S . -B build -G Ninja -DBOARD=longan -DCMAKE_TOOLCHAIN_FILE=cmake/toolchain-gnu-riscv64.cmake
cmake --build build

Flash using whatever tools you normally use. The binaries will be found under ./build/path/to/project, e.g. ./build/examples/hello_libc/example_hello_libc.elf

There are .bin and .hex files as well for flash tools that do not support loading .elf files.

Supported boards

Working:

• Seeedstudio GD32VF1 development board
• Sipeed Longan Nano
• Sparkfun Red-V Redboard

In progress:

• Bouffalo Labs BL702 (XT-ZB1 dev board)
• Bouffalo Labs BL602
• Hosted environment (running as a Linux executable)

Future:

• ARM?
• ESP32-C3

Repository layout

The repository directory tree is organized as follows:

• arch/ contains code for a specific CPU architecture, such as thread context switching code.
• bsp/ contains code specific to each particular board, primarily pin configurations and onboard devices.
• core/ contains platform-independent code for the core kernel features
• dev/ contains device drivers
• examples/ contains code usage examples
• include/ contains some useful header files that are usable without anything from core or other Desideria code
• lib/ contains third-party libraries
• soc/ code specific to a chip or chip family, but that can be shared across all boards with that chip
• svd/ contains hardware descriptions used for generating the MMIO headers
• sys/ contains libraries that are useful to applications but not required by the core kernel
• test/ contains automated tests to run on devices
• tools/ contains host side tools