[seL4] SMC in seL4

Hello, I'm porting sel4 to imx6q sabrelite as the trusted OS in trustzone. I initialize the monitor mode directly using the functions "install_monitor_hook()" and “switch_to_mon_mode()”. Is the sp in monitor mode appropriate? After calling smc in SVC mode, it hangs(do nothing in smc_handle()). What's wrong with it? Do you have any ideas? Thank you! Dongxu Ji