Some ASH WARE users develop timing data in spreadsheets and then output it into the form of the test vector language for use in the simulation tool (see examples and documentation for details on the test vector language that can be used to drive input signals). Certainly the same technique can be used for .csv files. Large (many MB) test vector files have been used to exercise some very long simulations (hours to days) in the past. This is a fairly straightforward technique.
Newer scripting capabilities support reading of .csv files into the script environment where the data could then be used to control timing and pin values via script commands. Almost for sure this would need to be done in its own script file, separate from the one that configures the eTPU and stimulates it via HSRs and memory writes. This is easy to do if a dual-engine (eTPU-A and B) simulation is set up - the main script file would be associated with eTPU-A, and the signal generation script would be associated with eTPU-B (but it could still drive pins on eTPU-A). What is the format of your .csv data?
John Diener