This is the upgrade path to any System Center 2012 R2 component:
System Center 2012 RTM > System Center 2012 SP1 > System Center 2012 R2.
As you can see, you need to upgrade to every major version, there are NO shortcuts here.
Translated to System Center 2012 – Operations Manager R2 (SCOM 2012 R2 / OM12 R2) this is the upgrade path:
SCOM 2012 RTM > SCOM 2012 SP1 > SCOM 2012 R2.
And when you’re running SCOM 2007 R2 and want to upgrade to SCOM 2012 R2, this is the upgrade path:
SCOM 2007 R2 > SCOM 2012 RTM > SCOM 2012 SP1 > SCOM 2012 R2.