diff --git a/README.adoc b/README.adoc
index 460dab6..c8cef05 100644
--- a/README.adoc
+++ b/README.adoc
@@ -12768,6 +12768,14 @@ exec filecode in scope
 
 TODO: the file path name appears to be passed as a command line argument to the Python script, but I didn't have the patience to fully understand the details.
 
+The Python config files then set the entire system up in Python, and finally call `m5.simulate()` to run the actual simulation. This function has a C++ native implementation at:
+
+....
+src/sim/simulate.cc
+....
+
+and that is where doSimLoop the main event loop, `doSimLoop` gets called and starts kicking off the <<gem5-event-queue>>.
+
 Tested at gem5 b4879ae5b0b6644e6836b0881e4da05c64a6550d.
 
 ==== gem5 event queue