Microsoft has released a KB 2801416. This describes about the sequence in which we need to perform upgrade CM 2012 RTM to Service Pack 1. First and foremost is Top to Down approach (CAS, Primary and then Secondary servers). Following are the 5 steps highlighted in the KB. I’ve already put together some interesting stuff that you must need to go through before upgrading your infra to SP1.
Step 1: Review the upgrade checklist
Step 2: Uninstall Windows Automated Installation Kit (AIK)
Step 3: Download and install Windows ADK
Step 4: Download and install Windows Management Framework 3.0
Step 5: Make sure that your version of Microsoft SQL Server is supported
Step 6: Install System Center 2012 Configuration Manager SP1