I finished the specifications for the bootloader yesterday.
I am currently working on creating the base chibiOS project. I have been working on the board.h a major part of the afternoon. It is quite long because there are a lot of registers to be configured. Indeed the board.h for the stm32f407 is a bit different from the board.h of the stm32f103CB because each feature is to be configured in a specific register.
I also took some time to learn to manage branches on GIT.