diff --git a/tcl/target/stm32h7x.cfg b/tcl/target/stm32h7x.cfg
index c9aec7612..0bfc43dfd 100644
--- a/tcl/target/stm32h7x.cfg
+++ b/tcl/target/stm32h7x.cfg
@@ -56,7 +56,17 @@ if {[using_jtag]} {
  jtag_ntrst_delay 100
 }
 
-# use hardware reset, connect under reset
+# use hardware reset
+#
+# The STM32H7 does not support connect_assert_srst mode because the AXI is
+# unavailable while SRST is asserted, and that is used to access the DBGMCU
+# component at 0x5C001000 in the examine-end event handler.
+#
+# It is possible to access the DBGMCU component at 0xE00E1000 via AP2 instead
+# of the default AP0, and that works with SRST asserted; however, nonzero AP
+# usage does not work with HLA, so is not done by default. That change could be
+# made in a local configuration file if connect_assert_srst mode is needed for
+# a specific application and a non-HLA adapter is in use.
 reset_config srst_only srst_nogate
 
 if {![using_hla]} {