[v2,0/2] perf: Add xilinx APM support

Message

Datta, Shubhrajyoti Dec. 22, 2022, 8:42 a.m. UTC

The programmable AXI performance monitors (APM) collect real-time
transaction metrics at multiple points on the PS AXI interconnect
to help system software profile real-time activity.
In our platform we have it in PL and also some of the hardened
instances in PS.

Perf is a profiler tool for Linux 2.6+ based systems that abstracts
away CPU hardware differences in Linux performance measurements and
presents a simple commandline interface.

Perf is based on the perf_events interface exported by recent versions of
the Linux kernel. Therefore we register to the framework for the APM.

The IP has support for multiple slots and ranges that we are supporting
by extending the sysfs interface.

Datasheet:
https://docs.xilinx.com/v/u/en-US/pg037_axi_perf_mon
Also the Hardened instances described in
AXI Performance Monitor of ug1085.


Changes in v2:
 - Use boolean for the values xlnx,enable-profile , xlnx,enable-trace
and xlnx,enable-event-count
- Update the file name
- use generic node name pmu
    - Fix a warn

Shubhrajyoti Datta (2):
  dt-bindings: Add the binding doc for xilinx APM
  perf: Add xilinx APM support

 .../bindings/perf/xlnx,axi-perf-monitor.yaml  | 133 ++++
 drivers/perf/Kconfig                          |  11 +
 drivers/perf/Makefile                         |   1 +
 drivers/perf/xilinx_apm.c                     | 666 ++++++++++++++++++
 4 files changed, 811 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/perf/xlnx,axi-perf-monitor.yaml
 create mode 100644 drivers/perf/xilinx_apm.c