I am trying to access the performance counters of a AMD CPU of family 14h.
As I understand there are two registers of interest as documented in the bios and kernel developer reference of the 14h family (attached):
- PERF_CTL[3:0] performance event select
- PERF_CTR[3:0] performance event counter
I set PERF_CTL which is at MSR0xC0010000 to value "0x400076" this should enable the counter and select event 76h
reading the value at PERF_CTR at MSR0xC0010004 it always return value ''0".
Are there any further registers I have to be aware of?
Please respond guys - I really appreciate your help.