If you talk civil to someone, I would assume you talk to them in a civil manner. Normally, if you talk to someone in a civil manner you speak to them in a polite but perhaps somewhat formal way. In certain contexts, it is possible that you speak to them in a slightly less than friendly way, as if forcing yourself to be polite. So, as is often the case, context is important.What does it mean if the manager talks civil to you?
Hope this helps.