You can upgrade from Oracle Reports 11gR2 to 12c. To upgrade from Oracle Reports 11g Release 2 to Oracle Reports 12c, see Oracle Fusion Middleware Upgrade Guide for Oracle Forms and Reports.
Upgrading from Oracle Reports 11.1.2 and 11.1.1 to 12c Release (12.2.1) is fully automated:
Integrated with Oracle Fusion Middleware Upgrade framework.
Automated configuration reduction mapping.
Extensive logging and diagnostics.
No loss of functionality.
Oracle Reports 12c Release (12.2.1) is fully backward compatible and interoperable with 11.1.2/11.1.1.
11.1.2/11.1.1 server/client compatible with 11g Release 2 (11.1.2) server/client.
11.1.2/11.1.1 reports can be run without any changes or loss of functionality.
Support for Oracle Portal and Oracle Internet Directory based security along with new Java EE security.
Support for 11.1.2. Toolkit-based font model along with new Java-based font model.
Support for interoperability with 11.1.2. Oracle Forms Services, Oracle Portal, and Oracle Internet Directory.