Add documentation for Cavium Coherent Processor Interconnect (CCPI2) PMU. Signed-off-by: Ganapatrao Kulkarni <gkulkarni@xxxxxxxxxxx> --- Documentation/perf/thunderx2-pmu.txt | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/Documentation/perf/thunderx2-pmu.txt b/Documentation/perf/thunderx2-pmu.txt index dffc57143736..01315b3d4ad9 100644 --- a/Documentation/perf/thunderx2-pmu.txt +++ b/Documentation/perf/thunderx2-pmu.txt @@ -2,24 +2,26 @@ Cavium ThunderX2 SoC Performance Monitoring Unit (PMU UNCORE) ============================================================= The ThunderX2 SoC PMU consists of independent, system-wide, per-socket -PMUs such as the Level 3 Cache (L3C) and DDR4 Memory Controller (DMC). +PMUs such as the Level 3 Cache (L3C), DDR4 Memory Controller (DMC) and +Cavium Coherent Processor Interconnect (CCPI2). The DMC has 8 interleaved channels and the L3C has 16 interleaved tiles. Events are counted for the default channel (i.e. channel 0) and prorated to the total number of channels/tiles. -The DMC and L3C support up to 4 counters. Counters are independently -programmable and can be started and stopped individually. Each counter -can be set to a different event. Counters are 32-bit and do not support -an overflow interrupt; they are read every 2 seconds. +The DMC and L3C support up to 4 counters, while the CCPI2 supports up to 8 +counters. Counters are independently programmable to different events and +can be started and stopped individually. None of the counters support an +overflow interrupt. DMC and L3C counters are 32-bit and read every 2 seconds. +The CCPI2 counters are 64-bit and assumed not to overflow in normal operation. PMU UNCORE (perf) driver: The thunderx2_pmu driver registers per-socket perf PMUs for the DMC and -L3C devices. Each PMU can be used to count up to 4 events -simultaneously. The PMUs provide a description of their available events -and configuration options under sysfs, see -/sys/devices/uncore_<l3c_S/dmc_S/>; S is the socket id. +L3C devices. Each PMU can be used to count up to 4 (DMC/L3C) or up to 8 +(CCPI2) events simultaneously. The PMUs provide a description of their +available events and configuration options under sysfs, see +/sys/devices/uncore_<l3c_S/dmc_S/ccpi2_S/>; S is the socket id. The driver does not support sampling, therefore "perf record" will not work. Per-task perf sessions are also not supported. -- 2.17.1
