Hello,
CPPC cpufreq driver is used for ARM servers and this patch series tries
to provide counter-based frequency invariance support for them in the
absence for architecture specific counters (like AMUs).
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.
Vincent/Ionela, it would be nice if you guys can give this a shot on
some real hardware where counters work.
This is based of pm/linux-next (need some stuff from the arm64 tree).
These patches should get merged via the arm64 tree only for the same
reason.
Changes since V2:
- Not sending as an RFC anymore.
- Several renames, reordering of code in 1/2 based on Ionela's comments.
- Several rebase changes for 2/2.
- The freq_scale calculations are optimized a bit.
- Better overall commenting and commit logs.
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
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 | 10 +-
arch/arm64/kernel/topology.c | 89 +++++++--------
drivers/base/arch_topology.c | 56 +++++++++-
drivers/cpufreq/cppc_cpufreq.c | 179 ++++++++++++++++++++++++++++--
include/linux/arch_topology.h | 15 ++-
kernel/sched/core.c | 1 +
6 files changed, 274 insertions(+), 76 deletions(-)
--
2.25.0.rc1.19.g042ed3e048af
