ARMV7 PMU event counter always return 0

I am want to use arm pmu to profile checksum algorithm performance, but the event counter always return 0, only cycle counter is normal. The step i use as follows: 1. enable user enable by setting...
Why I can't find the performance monitoring event for all Instructions count? How to get instructions event for my ARMV7 Cortex-A9 by PMU?

Can anyone help?
Why I can't find the performance monitoring event for all Instructions count? How to get instructions event for my ARMV7 Cortex-A9 by PMU?

Can anyone help?
Cortex-A35 Counter-timer Physical Count register (CNTPCT_EL0) always reads zero

Counter-timer Physical Count register CNTPCT_EL0 always reads zero on FVP_Base_Cortex-A35x1. I expect the value of this register to change over time. I set $CNTFRQ_EL0=35000000, and $CNTP_CTL_EL0...
Cortex-A35 Counter-timer Physical Count register (CNTPCT_EL0) always reads zero

Counter-timer Physical Count register CNTPCT_EL0 always reads zero on FVP_Base_Cortex-A35x1. I expect the value of this register to change over time. I set $CNTFRQ_EL0=35000000, and $CNTP_CTL_EL0...