I'm writing bare metal code (no OS), for an ARM Cortex A9 processor.
I need to read a register which is only accessible on supervisor mode (the multiprocessor affinity register, MPIDR).
When I'm in user mode and try to execute the following instruction (to enter supervisor mode) step by step with a debugger nothing happens.
MSR CPSR_C, #0x13
And my program goes to undefined mode, if I try to read the MPIDR register
Please do you know what i'm missing?
When i use the debugger windows, and force the five first bits of CPSR register to b10011, it works, I go to supervisor.