Hello,

I'm porting sel4 to imx6q sabrelite as the trusted OS in trustzone. I initialize the monitor mode by setting the sp to STACK_TOP and copying arm_monitor_vector to MON_VECTOR_START according to the functions "install_monitor_hook()" and "switch_to_mon_mode()" in "platform_init.c".

#define VECTOR_BASE 0x11000000(addr is not used by the seL4 kernel)

#define STACK_TOP (VECTOR_BASE + (1 << 12) - 0x10)

#define MON_VECTOR_START 0x11000000(The VECTOR_BASE is the same as MON_VECTOR_START)

The smc_handle() in monitor.S, it does nothing but "movs pc, lr". After calling smc in SVC mode, it hangs without any log. If I comment the "smc #0", it can return the caller successfully in usr mode.

stmfd sp!, {r3-r11, lr} dsb smc #0 ldmfd sp!, {r3-r11, pc}

Is the sp in monitor mode appropriate? Or I need to do something else in initialization operations? What's wrong with it? Do you have any ideas?

Thank you!

Dongxu Ji