Re: [PATCH v3 0/7] platform/x86/amd/pmf: Introduce PMF util layer with userspace interface

[Shyam Sundar S K <Shyam-sundar.S-k@amd.com>]

On 3/3/2026 01:06, Mario Limonciello wrote:
> On 3/1/26 7:11 AM, Shyam Sundar S K wrote:
>> This patch series introduces a new util layer for the AMD Platform
>> Management Framework (PMF) driver that exposes a minimal userspace
>> interface for metrics monitoring and feature discovery.
>>
>> AMD PMF currently manages power and thermal policies internally through
>> Smart PC features, Auto Mode, Policy Builder, Static/Dynamic Power
>> Sliders. However, system designers and OEMs need visibility into PMF
>> metrics and feature status for validation, debugging, and integration
>> with monitoring tools.
>>
>> This series addresses that need by adding a character device interface
>> that allows controlled access to PMF metrics data while maintaining
>> the driver's existing automated policy management.
>>
>> The primary use case is integration with userspace tools like AMD
>> SystemDeck, which are widely used by system designers to:
>> - Monitor real-time power and thermal behavior
>> - Validate PMF feature operation during platform bring-up
>> - Debug thermal issues by tracking skin temperature, C-state residency,
>>    and socket power metrics
>> - Verify BIOS input/output policy values during Smart PC operation
>>
>> The util layer reads from the existing Trusted Application (TA) shared
>> memory buffer and cached BIOS output values, adding no new
>> communication
>> overhead with the TA.
>>
>> v3:
>>   - Stop exporting battery information via util layer.
>>   - Optimize the core logic for fetching BIOS outputs.
>>   - Update the documentation patch to reflect the current util layer
>> design.
>>   - Consolidate amd-pmf-io.h changes into common UAPI header.
>>   - Define a single unified uAPI structure and IOCTL.
>>   - Address other v2 review remarks [1]
>>
>> v2:
>>   - address remarks from v1
>>   - add a new tool that exercises the IOCTLs from PMF interface
>>
>> [1] https://lore.kernel.org/platform-driver-
>> x86/20251111071010.4179492-1-Shyam-sundar.S-k@amd.com/
>>
>> Shyam Sundar S K (7):
>>    platform/x86/amd/pmf: Add util layer and userspace misc device
>>      interface
>>    platform/x86/amd/pmf: cache BIOS output values for user-space
>> metrics
>>      via util IOCTL
>>    platform/x86/amd/pmf: Add feature discovery support to util
>> interface
>>    platform/x86/amd/pmf: Store commonly used enums in the header file
>>    platform/x86/amd/pmf: Move debug helper functions to UAPI header
>>    platform/x86/amd/pmf: Introduce AMD PMF testing tool for driver
>>      metrics and features
>>    Documentation/ABI: add testing entry for AMD PMF misc device
>> interface
>>
>>   .../ABI/testing/misc-amdpmf_interface         |  70 ++++
>>   MAINTAINERS                                   |   1 +
>>   .../amd-sfh-hid/sfh1_1/amd_sfh_interface.c    |   1 +
>>   drivers/platform/x86/amd/pmf/Kconfig          |  10 +
>>   drivers/platform/x86/amd/pmf/Makefile         |   2 +
>>   drivers/platform/x86/amd/pmf/core.c           |   8 +
>>   drivers/platform/x86/amd/pmf/pmf.h            |  32 +-
>>   drivers/platform/x86/amd/pmf/spc.c            |  55 +--
>>   drivers/platform/x86/amd/pmf/tee-if.c         |   9 +-
>>   drivers/platform/x86/amd/pmf/util.c           | 210 ++++++++++++
>>   include/linux/amd-pmf-io.h                    |   9 -
>>   include/uapi/linux/amd-pmf.h                  | 324 ++++++++++++++
>> ++++
>>   tools/testing/selftests/Makefile              |   1 +
>>   .../drivers/platform/x86/amd/pmf/Makefile     |   8 +
>>   .../drivers/platform/x86/amd/pmf/test_pmf.c   | 243 +++++++++++++
>>   15 files changed, 897 insertions(+), 86 deletions(-)
>>   create mode 100644 Documentation/ABI/testing/misc-amdpmf_interface
>>   create mode 100644 drivers/platform/x86/amd/pmf/util.c
>>   create mode 100644 include/uapi/linux/amd-pmf.h
>>   create mode 100644 tools/testing/selftests/drivers/platform/x86/
>> amd/pmf/Makefile
>>   create mode 100644 tools/testing/selftests/drivers/platform/x86/
>> amd/pmf/test_pmf.c
>>
> 
> Thanks, looks good to me.  You can add this to the next version (which
> incorporates Randy's feedback).
> 
> Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
> 

Sure. Thanks! I will wait for other feedback to come in before
re-spinning.

Thanks,
Shyam