[TF-M] generated header files

I'm using the feature-ipc branch and I notice a lot of these warnings in TF-M header files:

/*********** WARNING: This is an auto-generated file. Do not edit! ***********/

When are these files generated? I assume they're derived from associated manifest files.

When I use cmake to create a "ConfigCoreIPC.cmake" build area, I don't see any header files being generated in the process. Any changes I've made to header files with these warnings are still present. Is there a TF-M cmake configuration that regenerates these files? If so, how do I invoke it so I can more properly reconfigure a custom SP?

Alan