Let me preface this by saying that I'm not an expert in this area (so I may get some things wrong), but Prime Infrastructure's SSO functionality is solely to integrate with other instances of Prime Infrastructure. If you're familiar with Prime Operations Center, which manages multiple instances of Prime Infrastructure and aggregates them into a single pane of glass, this SSO functionality is used to allow for users to quickly access the individual Prime Infrastructure instances and the Operations Center server. But you don't need to use Operations Center to use this SSO functionality.
SSO requires having multiple instances of Prime Infrastructure. You designate one instance as the SSO server. On that server, setup the SSO server settings. Then, on all the instances of Prime Infrastructure, add the SSO server. Now when users visit an instance of Prime Infrastructure, they'll be redirected to the SSO server to login, but will be able to access all instances of Prime Infrastructure without re-authenticating.
As far as I know, there is no support for integrating with SAML at this time.