The Canon EOS 5D Mark IV has just released for weeks, according to a post on ML forum, Magic Lantern now already have cracked the Canon EOS 5D Mark IV successfully, and will begin work on adding new features for a firmware release for 5D Mark IV.
Read all about the progress at Magic Lantern
Canon EOS 5D Mark IV is now in stock at most US stores. You may check 5D Mark IV deals here.