EFI Update for Macbook Unibody 2009 white (6.1)?

I have a Macbook Unibody 2009 white (6.1). It's still got a pretty good battery life and I've upgraded the RAM to 4gb and Mavericks runs quite well on it.

I have a problemn though. Which EFI update do I use? I put a Kingston SSD but it is showing only a Negotiated Link Speed of 1.5 and I want to improve it using the EFI update.... Every other macbook has updates, except the late 2009 white. 😟