This should work on OSX (not official instructions, just what worked for me):
ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
brew install dfu-util coreutils gnu-getopt
Note: Flashing takes a couple of minutes and there is no realtime progress meter etc. When the flashing is complete you will see a message saying “U-boot & Kernel System Flash Success…”