Integrating flashloader into MicroPython (RP2)

[cfpwastaken]

Checks

• I agree to follow the MicroPython Code of Conduct to ensure a safe and respectful space for everyone.

• I've searched for existing issues regarding this feature, and didn't find any.

Description

ESP32 users have "Partitions" and can do easy OTA updates in pure micropython code.
For RP2040 boards, there should be something similar, like adding flashloader as a second-stage bootloader and some functions exposing the API to python.
I found this discussion about OTA on RP2 ports.

I have marked both "I intend to implement this" and "I hope the MP maintainers or community will implement this" as I am willing to do it, but sadly do not have the capabilities to do this on my own. I have tried implementing it myself, but it does not compile. I can share my progress if needed.

Code Size

I'd definitely say it should be a toggle in the compiler options, but code size-wise, the bootloader only takes up 4kB, and i think it replaces the already existing boot2 bootloader, meaning that can't count towards the total size.

Implementation

• I intend to implement this feature and would submit a Pull Request if desirable.
• I hope the MicroPython maintainers or community will implement this feature.
• I would like to Sponsor development of this feature.