While working on the next revision of the moteus controller, I started by bringing up a software toolchain on a NUCLEO-G474RE board. Unfortunately, even the most recent mbed 5.14 doesn’t yet support that processor. Thus, I have a half-baked solution which pulls in the ST CUBE sources for that controller into the mbed tree as a patch.
The patch only implements wrappers for the things I care about, so it isn’t a complete solution. Since I am not really using any mbed libraries anymore in any project, that isn’t a whole lot. Right now I’m just using it for the one function that sets up the board, a linker script, and the pin mappings. I will probably eventually just make a rules_stm32 and ditch mbed entirely but for now that is more work than it is worth.