systemc: Disable the phase_callbacks set of tests.

This feature is experimental, nonstandard, and would in some cases be
difficult to implement in gem5.

Change-Id: Ic7fe77e6a2e9dbc5aba06579fb85fd2f055cb6b1
Reviewed-by: Gabe Black <>
Maintainer: Gabe Black <>
diff --git a/src/systemc/tests/working.filt b/src/systemc/tests/working.filt
index e28b74b..75cc837 100644
--- a/src/systemc/tests/working.filt
+++ b/src/systemc/tests/working.filt
@@ -12,6 +12,11 @@
 # something we're not currently planning to support.
+# Phase callbacks are an experimental feature. Also calling all the interested
+# sc_objects whenever time advances would add a non-trivial amount of
+# complexity and is probably not worth implementing in general.
 path in (
     # Uses sc_get_curr_simcontext.