Use the following links to access information that may be useful to you.
Oracle Support Center
Patches and updates downloads from My Oracle Support (MOS)
Oracle Key Manager documentation
Oracle Unified Storage Systems documentation
http://www.oracle.com/technetwork/documentation/oracle-unified-ss-193371.html
Oracle Enterprise Manager Concepts Guide
Management of Heterogeneous Data Centers Using Oracle Enterprise Manager Plug-ins (an Oracle White Paper)
http://www.oracle.com/technology/products/oem/pdf/dc_mgmt.pdf
Oracle Enterprise Manager Cloud Control 12c documentation, including the Oracle Enterprise Manager Concepts and Oracle Enterprise Manager Administration Guide
Oracle Enterprise Manager Cloud Control Upgrade Guide
https://download.oracle.com/docs/cd/E24628_01/upgrade.121/e22625.pdf
Oracle Enterprise Manager, Cloud Control Extensibility Programmers Reference, 12c Release3 (12.1.0.3.0)
http://docs.oracle.com/cd/E24628_01/doc.121/e25161/title.htm