[v2,0/2] Add CPU power management for CPU bound CTI devices.

Message

Mike Leach May 4, 2020, 4:15 p.m. UTC

Adds in power management for CPU bound CTI devices:
i) CPU Hotplug - registers a new notifier for CPU start and stop events.
ii) CPU idle PM event notifier to handle PM_ENTER, PM_ENTER_FAILED and
PM_EXIT events.

Tested with DB410c on Linux 5.7-rc3.
Rebased onto coresight/next

Changes since V1: (requested by Mathieu).
1) Split into separate patches for CPU pm and CPU hotplug handling.
2) Enable on hotplug has a specific function to enable the hardware,
while leaving the enable reference counts unchanged.

Mike Leach (2):
  coresight: cti: Add CPU Hotplug handling to CTI driver.
  coresight: cti: Add CPU idle pm notifer to CTI devices.

 drivers/hwtracing/coresight/coresight-cti.c | 173 ++++++++++++++++++++
 include/linux/cpuhotplug.h                  |   1 +
 2 files changed, 174 insertions(+)