Adds perf events support for L2 cache PMU.
The L2 cache PMU driver is named 'l2cache_0' and can be used
with perf events to profile L2 events such as cache hits
and misses on Qualcomm Technologies processors.
Signed-off-by: Neil Leeder <nleeder@xxxxxxxxxxxxxx>
Various style changes for function names & code restructuring
Replace dev_warn with ratelimited debug prints
Move hotplug registration before PMU registration
Reload counters with a fixed value
Add column-exclusion check for events in same group
Rebase on 4.10-rc3