Re: [PATCH 0/6] AMD Pstate Fixes And Enhancements

From: Tor Vic
Date: Wed Jan 31 2024 - 06:38:18 EST




On 1/31/24 09:50, Perry Yuan wrote:
The patch series adds some fixes and enhancements to the AMD pstate driver.
It enables CPPC v2 for certain processors in the family 17H, as requested
by TR40 processor users who expect improved performance and lower system
temperature.

Additionally, it fixes the initialization of nominal_freq for each cpudata
and changes latency and delay values to be read from platform firmware firstly
for more accurate timing.

A new quirk is also added for legacy processors that lack CPPC capabilities,
which caused the pstate driver to fail loading.

I would greatly appreciate any feedbacks.


Hi Perry,

Which tree or patchset is this based on?
It doesn't apply cleanly onto either 6.7 or 6.8.

First I had to revert [1], then apply [2] before applying this patchset and finally reapply [1].
I did not apply the "prefcore" patchset which I keep in a separate branch.

Is this correct or did I mess up something with my branches?

---
[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?h=v6.8-rc2&id=febab20caebac959fdc3d7520bc52de8b1184455

[2] https://lore.kernel.org/linux-pm/cover.1706255676.git.perry.yuan@xxxxxxx/

Cheers,
Tor Vic

Thank you!


Perry Yuan (6):
ACPI: CPPC: enable AMD CPPC V2 support for family 17h processors
cpufreq:amd-pstate: fix the nominal freq value set
cpufreq:amd-pstate: initialize nominal_freq of each cpudata
cpufreq:amd-pstate: get pstate transition delay and latency value from
ACPI tables
cppc_acpi: print error message if CPPC is unsupported
cpufreq:amd-pstate: add quirk for the pstate CPPC capabilities missing

arch/x86/kernel/acpi/cppc.c | 2 +-
drivers/acpi/cppc_acpi.c | 6 +-
drivers/cpufreq/amd-pstate.c | 112 ++++++++++++++++++++++++++++-------
include/linux/amd-pstate.h | 6 ++
4 files changed, 102 insertions(+), 24 deletions(-)