ARM Linux下的特权模式

Question

I'm using an ARM Cortex-A8. There is Linux Debian 4.6.2-11 distribution. I'm trying to get access the SysTick counter by reading SYST_RVR register, but now have Segmentation fault. In this regard, I have a question, whether it is accessible in privileged mode only? Since SegFault can be meant that a process is accessing a memory address, which is prohibited to it.

I also followed this thread How to measure program execution time in ARM Cortex-A8 processor? and also have "Illegal instruction" message

Answer 1

Are you trying to access it via 0xE000E014? There's no such register on Cortex A series. It makes sense if you get illegal access / segmentation error.