What is this about?

We make ChibiOS independent of Makefiles, thus enabling its use in PlatformIO (or any other build system.) This is an experimental effort.

How?

Ahead of time, we selectively package sources relevant to your platform of choice. This is done by invoking make lib -n on maintained Makefiles. We parse the make stdout to obtain the list of files required. These are then packaged into a library zip for each MCU family.

Your job is to use the package zipped up for your MCU family and fill in the gaps:

Usage

1. Get chconf.h, mcuconf.h and halconf.h (from ChibiOS/os/{hal|rt}/templates), edit for your needs, and place them so that they are seen by Chibi sources.
2. Get syscalls.c (from ChibiOS/os/various); also may need to dummy-define _exit, _kill, _getpid.
3. Get the linker script files (from ChibiOS/os/common/startup)
4. Define linker symbols __process_stack_size__, __main_stack_size__ to specify the size of stacks.

Example platformio.ini

# platformio.ini
[platformio]

[env:myboard]
platform = ststm32
board_upload.maximum_size = 32768
board_build.ldscript = STM32fromchibios.ld
build_flags =
  ${env.build_flags}
  -Iinclude # Make sure Chibi sees our *conf.h files
  -Wl,--defsym=__process_stack_size__=0x400 # For the main() thread
  -Wl,--defsym=__main_stack_size__=0x200 # For ISRs

# For L0:
lib_deps = ChibiPIO-STM32L0

build_type = debug
extra_scripts =
  pre:pre_linker_specs.py

# pre_linker_specs.py
# Required for shrinking flash usage when we don't use "framework=cmsis" (applies for Newlib)
Import("env")
env.Append(
    LINKFLAGS=[
        "--specs=nano.specs",
        "--specs=nosys.specs"
    ]
)

Notes

Some simplifications were made to get this up and running:

• ChibiOS/RT and ChibiOS/HAL are packaged together
• Only GCC was considered
• Only Cortex-M was considered
• ARM/Thumb interwork was not considered

Side effects compared to the Makefile solution:

• Support for each new platform must be explicitly added.
• Compile parameters (like -fno-rtti) normally specified in the ChibiOS Makefile are lost.
• FPU (hard/soft) build options must be handled manually
• "Smart build" functionality (where only relevant sources are compiled) is lost. This is a non-issue IMHO, Chibi sources are quick to compile nowadays.