From f6ee11d77d15ff10f8a804eec529a7092bbb46a6 Mon Sep 17 00:00:00 2001 From: Shyam Sundar S K Date: Tue, 9 Jun 2026 13:40:44 +0530 Subject: [PATCH] Documentation/ABI: add testing entry for AMD PMF character device interface MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add a Documentation/ABI/testing entry describing the AMD PMF util layer character device (/dev/amdpmf_interface) and the initial ioctl used to query feature support and metrics data information. This interface is available when CONFIG_AMD_PMF_UTIL_SUPPORT=y. Also update the MAINTAINERS record with the new UAPI header. Signed-off-by: Shyam Sundar S K Link: https://patch.msgid.link/20260609081044.2416731-8-Shyam-sundar.S-k@amd.com Reviewed-by: Ilpo Järvinen Signed-off-by: Ilpo Järvinen --- Documentation/ABI/testing/amdpmf-interface | 73 ++++++++++++++++++++++ MAINTAINERS | 1 + 2 files changed, 74 insertions(+) create mode 100644 Documentation/ABI/testing/amdpmf-interface diff --git a/Documentation/ABI/testing/amdpmf-interface b/Documentation/ABI/testing/amdpmf-interface new file mode 100644 index 000000000000..625f90a013d0 --- /dev/null +++ b/Documentation/ABI/testing/amdpmf-interface @@ -0,0 +1,73 @@ +What: /dev/amdpmf_interface +Date: June 2026 +KernelVersion: 7.2 +Contact: Shyam Sundar S K +Description: + The AMD Platform Management Framework (PMF) util layer exposes a + minimal user-space interface via a character device for feature + discovery and metrics monitoring. + + When CONFIG_AMD_PMF_UTIL_SUPPORT is enabled, the driver creates + a character device: + + ====================== + /dev/amdpmf_interface + ====================== + + The interface supports a single ioctl: + + ============================ ======================================= + IOCTL Usage + IOCTL_AMD_PMF_POPULATE_DATA User passes a struct amd_pmf_info with + the size field set to sizeof(struct + amd_pmf_info). The driver returns all + available metrics and feature status + in the structure. + ============================ ======================================= + + struct amd_pmf_info layout: + + ======================= ========== ================================ + Field Type Description + size __u64 Structure size for versioning + features_supported __u32 Bitmask of supported features + platform_type __u32 Platform form factor orientation + power_source __u32 AC/DC power source + laptop_placement __u32 Device placement state + lid_state __u32 Lid open/closed status + user_presence __u32 User presence detection + slider_position __u32 Current power slider position + skin_temp __s32 Skin temperature (centidegrees) + gfx_busy __u32 Graphics workload percentage + ambient_light __s32 Ambient light sensor reading + avg_c0_residency __u32 Average C0 state residency + max_c0_residency __u32 Maximum C0 state residency + socket_power __u32 Socket power consumption + bios_input[10] __u32 Custom BIOS input parameters + bios_output[10] __u32 Custom BIOS output parameters + ======================= ========== ================================ + + Feature Support Flags (features_supported bitmask): + + ===================================== ==== ============================= + Flag Bit Description + AMD_PMF_FEAT_AUTO_MODE 0 Auto Mode feature support + AMD_PMF_FEAT_STATIC_POWER_SLIDER 1 Static Power Slider support + AMD_PMF_FEAT_POLICY_BUILDER 2 Policy Builder (Smart PC) + AMD_PMF_FEAT_DYNAMIC_POWER_SLIDER_AC 3 Dynamic slider on AC + AMD_PMF_FEAT_DYNAMIC_POWER_SLIDER_DC 4 Dynamic slider on DC + ===================================== ==== ============================= + + Return codes: + + ============= ============================================================ + Return code Description + 0 Success + EINVAL Invalid size or parameter + EFAULT copy_to_user/copy_from_user failures + ENODEV PMF device not available + ENOTTY Unknown ioctl command + ============= ============================================================ + + User-space tools integrating with AMD PMF to discover capabilities and + monitor real-time metrics for thermal and power management validation. diff --git a/MAINTAINERS b/MAINTAINERS index 1ef1ec374eab..3820b286f09f 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1263,6 +1263,7 @@ L: platform-driver-x86@vger.kernel.org S: Supported F: Documentation/ABI/testing/sysfs-amd-pmf F: drivers/platform/x86/amd/pmf/ +F: include/uapi/linux/amd-pmf.h AMD POWERPLAY AND SWSMU M: Kenneth Feng