Embedded Firmware Base

This repo contains a set of common base libraries for writing bare-metal embedded firmware for a variety of targets.

Supported Targets

While there's no real architectural concerns in most of the shared code provided, only the following architectures have been tested to work:

• ARM
  • Cortex-M4F: Atmel ATSAMD5x, STM32MP15x MCU core
  • Cortex-M33: Silicon Labs EFR32FG23

Support for RISC-V platforms is (eventually) planned.

Additional Requirements

Only clang/llvm is supported to build the library code. You'll need to provide your own toolchain (and toolchain files) as well.

Integration

To use the libraries, you need to somehow add this CMake project as a dependency on your embedded firmware's project. There are several ways to go about this, the easiest being automatically fetching it with FetchContent:

FetchContent_Declare(
    fw-base
    GIT_REPOSITORY https://github.com/tristanseifert/embedded-fw-base.git
    GIT_TAG main
)
FetchContent_MakeAvailable(fw-base)
link_libraries(embedded-fw-base::libc)

Once integrated, you can link with the various targets. Create a firmware image with the following command:

add_firmware_executable(NAME firmware FILENAME "output-filename"
    LDSCRIPT ${CMAKE_CURRENT_LIST_DIR}/script.ld
    LDMAP ${CMAKE_CURRENT_BINARY_DIR}/output.map
    SOURCES
    Sources/Main.cpp
)

Configuration

Various CMake options can be set to determine how to build the library.

Required

These options are required:

• EFWB_TARGET: Processor family to target. This automatically configures the applied HAL, libraries, etc.
  • Currently supported values are stm32mp15x and efr32fg23.

Usage

Once the library has been configured for a particular target, you can define a new firmware image with the add_firmware_executable command exported by this library's build script. Its semantics are very similar to the basic add_executable command, but will configure compiler and linker options appropriately.