Accessing privilege mode from user mode in Cortex A8

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1

Hello,

I want to access privilege mode of the cortex A8 processor from user
mode. I have read the DDI0344H_cortex_a8_r3p0_trm.pdf. In that it is
given that to go from user mode to privilege mode exception required
to apply. I am not getting exactly how to do it. So can any one tell
me how to apply exception to enter in that mode? If some one having
code lines then it will help me much.

Thanks,
Ritika

2

Privileged modes are intended for the OS to use, and it is intentional
that there is no easy way to switch away from user mode. The SWI/SVC
instruction is the normal way to call an OS (you need an exception
handler on 0x8). What are you trying to do?

3

Hi,

I tried to write this instruction but from the manual I am not clearly
getting how to write the SWI/SVC to call OS. Can you give any
suggestions?

Thanks,
RItika