diff --git a/tcl/target/stm32f4x.cfg b/tcl/target/stm32f4x.cfg
index 35d8275b5..a77527c46 100644
--- a/tcl/target/stm32f4x.cfg
+++ b/tcl/target/stm32f4x.cfg
@@ -98,6 +98,9 @@ proc _proc_pre_enable_$_CHIPNAME.tpiu {_chipname} {
 	targets $_chipname.cpu
 
 	if { [$_chipname.tpiu cget -protocol] eq "sync" } {
+		# Enable the GPIOE clock.
+		mmw 0x40023830 0x00000010 0x00000010
+
 		switch [$_chipname.tpiu cget -port-width] {
 			1 {
 				# Set TRACE_IOEN; TRACE_MODE to sync 1 bit; GPIOE[2-3] to AF0