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1What: /sys/class/intel_pmt/features-<PCI BDF>/
2Date: 2025-04-24
3KernelVersion: 6.16
4Contact: david.e.box@linux.intel.com
5Description:
6 The `features-<PCI BDF>/` directory represents the "features"
7 capability exposed by Intel PMT (Platform Monitoring Technology)
8 for the given PCI device.
9
10 Each directory corresponds to a PMT feature and contains
11 attributes describing the available telemetry, monitoring, or
12 control functionalities.
13
14Directory Structure:
15
16 /sys/class/intel_pmt/features-<PCI BDF>/
17 ├── accelerator_telemetry/ # Per-accelerator telemetry data
18 ├── crash_log/ # Contains system crash telemetry logs
19 ├── per_core_environment_telemetry/ # Environmental telemetry per core
20 ├── per_core_performance_telemetry/ # Performance telemetry per core
21 ├── per_rmid_energy_telemetry/ # Energy telemetry for RMIDs
22 ├── per_rmid_perf_telemetry/ # Performance telemetry for RMIDs
23 ├── tpmi_control/ # TPMI-related controls and telemetry
24 ├── tracing/ # PMT tracing features
25 └── uncore_telemetry/ # Uncore telemetry data
26
27Common Files (Present in all feature directories):
28
29 caps
30 - Read-only
31 - Lists available capabilities for this feature.
32
33 guids
34 - Read-only
35 - Lists GUIDs associated with this feature.
36
37Additional Attributes (Conditional Presence):
38
39 max_command_size
40 - Read-only
41 - Present if the feature supports out-of-band MCTP access.
42 - Maximum supported MCTP command size for out-of-band PMT access (bytes).
43
44 max_stream_size
45 - Read-only
46 - Present if the feature supports out-of-band MCTP access.
47 - Maximum supported MCTP stream size (bytes).
48
49 min_watcher_period_ms
50 - Read-only
51 - Present if the feature supports the watcher API.
52 The watcher API provides a writable control interface that allows user
53 configuration of monitoring behavior, such as setting the sampling or
54 reporting interval.
55 - Minimum supported time period for the watcher interface (milliseconds).
56
57 num_rmids
58 - Read-only
59 - Present if the feature supports RMID (Resource Monitoring ID) telemetry.
60 RMIDs are identifiers used by hardware to track and report resource usage,
61 such as memory bandwidth or energy consumption, on a per-logical-entity
62 basis (e.g., per core, thread, or process group).
63 - Maximum number of RMIDs tracked simultaneously.
64
65Example:
66For a device with PCI BDF `0000:00:03.1`, the directory tree could look like:
67
68 /sys/class/intel_pmt/features-0000:00:03.1/
69 ├── accelerator_telemetry/
70 │ ├── caps
71 │ ├── guids
72 │ ├── max_command_size
73 │ ├── max_stream_size
74 │ ├── min_watcher_period_ms
75 ├── crash_log/
76 │ ├── caps
77 │ ├── guids
78 │ ├── max_command_size
79 │ ├── max_stream_size
80 ├── per_core_environment_telemetry/
81 │ ├── caps
82 │ ├── guids
83 │ ├── max_command_size
84 │ ├── max_stream_size
85 │ ├── min_watcher_period_ms
86 ├── per_rmid_energy_telemetry/
87 │ ├── caps
88 │ ├── guids
89 │ ├── max_command_size
90 │ ├── max_stream_size
91 │ ├── min_watcher_period_ms
92 │ ├── num_rmids
93 ├── tpmi_control/
94 │ ├── caps
95 │ ├── guids
96 ├── tracing/
97 │ ├── caps
98 │ ├── guids
99 ├── uncore_telemetry/
100 │ ├── caps
101 │ ├── guids
102 │ ├── max_command_size
103 │ ├── max_stream_size
104 │ ├── min_watcher_period_ms
105
106Notes:
107 - Some attributes are only present if the corresponding feature supports
108 the capability (e.g., `max_command_size` for MCTP-capable features).
109 - Features supporting RMIDs include `num_rmids`.
110 - Features supporting the watcher API include `min_watcher_period_ms`.
111 - The `caps` file provides additional information about the functionality
112 of the feature.
113
114Example 'caps' content for the 'tracing' feature:
115
116 /sys/class/intel_pmt/features-0000:00:03.1/
117 ├── tracing/
118 │ ├── caps
119
120 telemetry Available: No
121 watcher Available: Yes
122 crashlog Available: No
123 streaming Available: No
124 threashold Available: No
125 window Available: No
126 config Available: Yes
127 tracing Available: No
128 inband Available: Yes
129 oob Available: Yes
130 secure_chan Available: No
131 pmt_sp Available: Yes
132 pmt_sp_policy Available: Yes
133 mailbox Available: Yes
134 bios_lock Available: Yes