2012 has the H310 drivers built-in, but 2008 R2 is too old and needs them added.  You can extract the files from the Update Package for Microsoft Windows version manually or just use the "hard drive" (ZPE) version: [URL] Download and run to extract the files before use.
I've got PowerEdge T320 with H320 PERC.  While Windows server 2012 installation procedure recognizes RAID1 disk that I've created, Windows server 2008 R does not recognize it. I've tried to find controller drivers for WS 2008 R2, but all I could find was some updates for allready installed servers. Where can I find drivers that i could use in install procedure? 
Drivers for Windows server 2008 R2