[RFC V2 0/2] cpufreq: cppc: Add support for frequency invariance

[Viresh Kumar]

Hello,

CPPC cpufreq driver is used for ARM servers and this patch series tries
to provide frequency invariance support for them.

This is tested with some hacks, as I didn't have access to the right
hardware, on the ARM64 hikey board to check the overall functionality
and that works fine.

Ionela/Peter Puhov, it would be nice if you guys can give this a shot.

This is based of pm/linux-next and patches [1] and [2] which I sent
recently to cleanup arm64 topology stuff.

Changes since V1:
- The interface for setting the callbacks is improved, so different
  parts looking to provide their callbacks don't need to think about
  each other.

- Moved to per-cpu storage for storing the callback related data, AMU
  counters have higher priority with this.

--
viresh

[1] https://lore.kernel.org/lkml/7a171f710cdc0f808a2bfbd7db839c0d265527e7.1607579234.git.viresh.kumar@xxxxxxxxxx/
[2] https://lore.kernel.org/lkml/5ffc7b9ed03c6301ac2f710f609282959491b526.1608010334.git.viresh.kumar@xxxxxxxxxx/

Viresh Kumar (2):
  topology: Allow multiple entities to provide sched_freq_tick()
    callback
  cpufreq: cppc: Add support for frequency invariance

 arch/arm64/include/asm/topology.h |   8 +-
 arch/arm64/kernel/topology.c      |  89 +++++++++----------
 drivers/base/arch_topology.c      |  56 +++++++++++-
 drivers/cpufreq/cppc_cpufreq.c    | 140 +++++++++++++++++++++++++++++-
 include/linux/arch_topology.h     |  14 ++-
 kernel/sched/core.c               |   1 +
 6 files changed, 244 insertions(+), 64 deletions(-)

-- 
2.25.0.rc1.19.g042ed3e048af