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authorRob Herring (Arm) <robh@kernel.org>2026-08-31 14:43:51 -0500
committerDmitry Torokhov <dmitry.torokhov@gmail.com>2026-09-13 18:17:31 -0700
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Input: tsc2007 - read "ti,poll-period" as u32grafted
The "ti,poll-period" property is documented as a normal uint32 cell. The driver used a u64 helper, which makes the helper type disagree with the schema even though the stored value is still small. Read "ti,poll-period" with the u32 helper matching the documented DT cell size. Assisted-by: Codex:gpt-5-5 Signed-off-by: Rob Herring (Arm) <robh@kernel.org> Link: https://patch.msgid.link/20260831194352.1185860-1-robh@kernel.org Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
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+.. SPDX-License-Identifier: GPL-2.0+
+
+============================
+DRM RAS over Generic Netlink
+============================
+
+The DRM RAS (Reliability, Availability, Serviceability) interface provides a
+standardized way for GPU/accelerator drivers to expose error counters and
+other reliability nodes to user space via Generic Netlink. This allows
+diagnostic tools, monitoring daemons, or test infrastructure to query hardware
+health in a uniform way across different DRM drivers.
+
+Key Goals:
+
+* Provide a standardized RAS solution for GPU and accelerator drivers, enabling
+ data center monitoring and reliability operations.
+* Implement a single drm-ras Generic Netlink family to meet modern Netlink YAML
+ specifications and centralize all RAS-related communication in one namespace.
+* Support a basic error counter interface, addressing the immediate, essential
+ monitoring needs.
+* Offer a flexible, future-proof interface that can be extended to support
+ additional types of RAS data in the future.
+* Allow multiple nodes per driver, enabling drivers to register separate
+ nodes for different IP blocks, sub-blocks, or other logical subdivisions
+ as applicable.
+
+.. contents::
+
+Nodes
+=====
+
+Nodes are logical abstractions representing an error type or error source within
+the device. Currently, only error counter nodes is supported.
+
+Drivers are responsible for registering and unregistering nodes via the
+`drm_ras_node_register()` and `drm_ras_node_unregister()` APIs.
+
+Node Management
+-------------------
+
+.. kernel-doc:: drivers/gpu/drm/drm_ras.c
+ :doc: DRM RAS Node Management
+.. kernel-doc:: drivers/gpu/drm/drm_ras.c
+ :internal:
+
+Generic Netlink Usage
+=====================
+
+The interface is implemented as a Generic Netlink family named ``drm-ras``.
+User space tools can:
+
+* List registered nodes with the ``list-nodes`` command.
+* List all error counters in an node with the ``get-error-counter`` command with ``node-id``
+ as a parameter.
+* Query specific error counter values with the ``get-error-counter`` command, using both
+ ``node-id`` and ``error-id`` as parameters.
+* Clear specific error counters with the ``clear-error-counter`` command, using both
+ ``node-id`` and ``error-id`` as parameters.
+
+YAML-based Interface
+--------------------
+
+The interface is described in a YAML specification ``Documentation/netlink/specs/drm_ras.yaml``
+
+This YAML is used to auto-generate user space bindings via
+``tools/net/ynl/pyynl/ynl_gen_c.py``, and drives the structure of netlink
+attributes and operations.
+
+Usage Notes
+-----------
+
+* User space must first enumerate nodes to obtain their IDs.
+* Node IDs or Node names can be used for all further queries, such as error counters.
+* Error counters can be queried by either the Error ID or Error name.
+* Query Parameters should be defined as part of the uAPI to ensure user interface stability.
+* The interface supports future extension by adding new node types and
+ additional attributes.
+
+Example: List nodes using ynl
+
+.. code-block:: bash
+
+ sudo ynl --family drm_ras --dump list-nodes
+ [{'device-name': '0000:03:00.0',
+ 'node-id': 0,
+ 'node-name': 'correctable-errors',
+ 'node-type': 'error-counter'},
+ {'device-name': '0000:03:00.0',
+ 'node-id': 1,
+ 'node-name': 'uncorrectable-errors',
+ 'node-type': 'error-counter'}]
+
+Example: List all error counters using ynl
+
+.. code-block:: bash
+
+ sudo ynl --family drm_ras --dump get-error-counter --json '{"node-id":0}'
+ [{'error-id': 1, 'error-name': 'error_name1', 'error-value': 0},
+ {'error-id': 2, 'error-name': 'error_name2', 'error-value': 0}]
+
+Example: Query an error counter for a given node
+
+.. code-block:: bash
+
+ sudo ynl --family drm_ras --do get-error-counter --json '{"node-id":0, "error-id":1}'
+ {'error-id': 1, 'error-name': 'error_name1', 'error-value': 0}
+
+Example: Clear an error counter for a given node
+
+.. code-block:: bash
+
+ sudo ynl --family drm_ras --do clear-error-counter --json '{"node-id":0, "error-id":1}'
+ None