...
- license agreements is valid (between developer/employer and project)
- coding style matches (many projects have scripts that can be used to check a patch)
- patch size is appropriate and not too large (use more patches of smaller size instead of a single large patch)
- commit messages (headline, body with what? and why?, additional information as needed by project)
- tests (all code must be tested to save your future self and other time)
Additionally, please consider this for each community to which you wish to submit a patch:
- how/where the community communicates (email list, IRC, Slack, Discord, ...)
- how the community is governed (who is the maintainer? are there sub-maintainers? are there key experts not in leadership positions but who have influence?)
- who represents RISC-V in the community