Merging in a new Target

LLVM team,

I am working on developing a new target for LLVM for the Propeller 2 microcontroller in this repo. While this is still highly experimental, it’s getting to a point where I’d like to merge it into main LLVM for others to work on, as well as stay up to date with the changes being made to LLVM. What is expected to have complete before submitting a patch, and since you don’t accept git PRs, what’s the process to submitting the changes I’ve developed?