Re: [PATCH v3 0/9] cpufreq/amd-pstate: BIOS min perf fixes and Dynamic EPP rework

[Mario Limonciello <mario.limonciello@amd.com>]

On 7/27/26 02:20, K Prateek Nayak wrote:
> This is a follow up of
> https://lore.kernel.org/lkml/20260723201228.22584-1-kprateek.nayak@amd.com/
> with comments from Mario and Sashiko addressed.
> 
> Patches are based on:
> 
>    git.kernel.org/pub/scm/linux/kernel/git/superm1/linux.git bleeding-edge
> 
> at commit 39c0cf62fc78 ("cpufreq/amd-pstate: handle missing policy in
> dynamic EPP callbacks")
> 
> Everyone has been Cc'd on the cover letter. Respective maintainers have
> been Cc'd on the relevant patches to reduce noise. Lists get the full
> series.
> ---
> changelog v2..v3:
> 
> o Ensure min_limit_perf is always <= max_limi_perf when adhering to
>    bios_min_perf constraints. (Sashiko)
> 
> o Fix the units in debug message to KHz. (Sashiko)
> 
> o Added a policy check for dynamic mode toggle. (Sashiko)
> 
> o Reworded documentation based on suggestion. (Mario)
> 
> o Collected tags from Mario and fix typos highlighted. (Thanks a ton!)
> 
> Some Sashiko reviews haven't been addressed in this series:
> 
> Mixing of __free() and goto was considered safe as long as they are in
> the same scope and programmers know what they are doing. (See
> https://lore.kernel.org/all/20260327152052.GJ3738010@noisy.programming.kicks-ass.net/)
> (The flagging was unrelated to changes in this series)
> 
> Kdump scenario for bios_floor_perf is ignored as (afaik) kdump kernels
> are loaded temporarily for debug and dumping out data structures that
> are preserved from last crash, and an inaccurate bios_min_perf during
> this process should be acceptable.
> 
> System profile notifiers do not grab the policy sem to prevent a
> deadlock with disable path. Disable path already grabs the read end and
> a pending notifier must finish for it to be removed. Since the driver
> disallows EPP modifications in dynamic mode, this is handled by the
> driver without needing to grab the policy sem in notifier handler.
> 
> amd-pstate-ut is considered a developer test and is supposed to be run
> in isolation without any parallel modifications to driver settings. As
> such, any of those concerns have not been addressed here.
> ---
> K Prateek Nayak (9):
>    cpufreq/amd-pstate: Set min_limit_freq based on bios_min_perf
>    cpufreq/amd-pstate: Remove the defensive check for bios_min_perf
>    cpufreq/amd-pstate: Extract platform profile to EPP conversion into a
>      helper
>    cpufreq/amd-pstate: Add dynamic EPP as an
>      "energy_performance_preference" mode
>    cpufreq/amd-pstate: Remove "amd_dynamic_epp" cmdline and "dynamic_epp"
>      sysfs
>    Documentation/amd-pstate: Update dynamic_epp documentation with new
>      behavior
>    cpufreq/amd-pstate: Reduce the scope of exported symbols
>    cpufreq/amd-pstate-ut: Add unit test for "dynamic" EPP mode
>    cpufreq/amd-pstate-ut: Add unit test for CPPC Performance Priority
> 
>   Documentation/admin-guide/pm/amd-pstate.rst |  45 ++--
>   drivers/cpufreq/amd-pstate-ut.c             | 131 ++++++++--
>   drivers/cpufreq/amd-pstate.c                | 251 ++++++++++----------
>   drivers/cpufreq/amd-pstate.h                |   9 +
>   4 files changed, 262 insertions(+), 174 deletions(-)
> 
> 
> base-commit: 39c0cf62fc7851a17782e7efe8dfb2948739c681

Thanks, I'll pick these up and continue to test.  If all looks good I'll 
include in my last PR for 7.3.

Thanks!