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=5.
What is the possible reasons, and how is there any configuration I need make to enable this counter? Thanks
Hi Tao,
The counter is not counting because the CNTVALUEB input to the Cortex-A35 is driven by a model which requires some programming to start supplying the clock for the counters. If you are interested the model is the MemoryMappedCounterModule.
You can get around this by setting a parameter in the model to just start counting and the counter will count.
Add
-C bp.refcounter.non_arch_start_at_default=1
to your command line for FVP_Base_Cortex-A35x1 and it will work.
Thanks,
Jason
Jason,
It's validated. You saved my week. Thank you so much.
Tao