Ampere SoC Performance Monitoring Unit (PMU)¶
Ampere SoC PMU is a generic PMU IP that follows Arm CoreSight PMU architecture. Therefore, the driver is implemented as a submodule of arm_cspmu driver. At the first phase it’s used for counting MCU events on AmpereOne.
MCU PMU events¶
The PMU driver supports setting filters for “rank”, “bank”, and “threshold”. Note, that the filters are per PMU instance rather than per event.
Example for perf tool use:
/ # perf list ampere
ampere_mcu_pmu_0/act_sent/ [Kernel PMU event]
<...>
ampere_mcu_pmu_1/rd_sent/ [Kernel PMU event]
<...>
/ # perf stat -a -e ampere_mcu_pmu_0/act_sent,bank=5,rank=3,threshold=2/,ampere_mcu_pmu_1/rd_sent/ \
sleep 1