Index: tools/ew.py
===================================================================
--- tools/ew.py	(revision c7a67c4164e47071669eabcb1ab3e57b3e80ab10)
+++ tools/ew.py	(revision e4d7363ab09538c786991a26952f1695de85df2c)
@@ -160,4 +160,9 @@
 	return ' -usb'
 
+def qemu_xhci_options():
+	if is_override('noxhci'):
+		return ''
+	return ' -device nec-usb-xhci,id=xhci'
+
 def qemu_audio_options():
 	if is_override('nosnd'):
@@ -180,4 +185,6 @@
 	if (not 'usb' in cfg.keys()) or cfg['usb']:
 		cmdline += qemu_usb_options()
+	if (not 'xhci' in cfg.keys()) or cfg['xhci']:
+		cmdline += qemu_xhci_options()
 	if (not 'audio' in cfg.keys()) or cfg['audio']:
 		cmdline += qemu_audio_options()
@@ -286,5 +293,5 @@
 def usage():
 	print("%s - emulator wrapper for running HelenOS\n" % os.path.basename(sys.argv[0]))
-	print("%s [-d] [-h] [-net e1k|rtl8139|ne2k] [-nohdd] [-nokvm] [-nonet] [-nosnd] [-nousb]\n" %
+	print("%s [-d] [-h] [-net e1k|rtl8139|ne2k] [-nohdd] [-nokvm] [-nonet] [-nosnd] [-nousb] [-noxhci]\n" %
 	    os.path.basename(sys.argv[0]))
 	print("-d\tDry run: do not run the emulation, just print the command line.")
@@ -295,4 +302,5 @@
 	print("-nosnd\tDisable sound, if applicable.")
 	print("-nousb\tDisable USB support, if applicable.")
+	print("-noxhci\tDisable XHCI support, if applicable.")
 
 def fail(platform, machine):
@@ -336,4 +344,6 @@
 		elif sys.argv[i] == '-nousb':
 			overrides['nousb'] = True
+		elif sys.argv[i] == '-noxhci':
+			overrides['noxhci'] = True
 		else:
 			usage()