[hipBLASLt] Docs: Add environment variable reference page

projects/hipblaslt/docs/index.rst

@@ -44,6 +44,7 @@ The hipBLASLt public repository is located at `<https://github.com/ROCm/hipBLASL
 
     * :doc:`Data type support <./reference/data-type-support>`
     * :doc:`hipBLASLt datatypes <./reference/datatypes>`
+    * :doc:`hipBLASLt environment variables <./reference/env-variables>`
     * :doc:`hipBLASLt API <./reference/api-reference>`
     * :doc:`hipBLASLtExt API <./reference/ext-reference>`
     * :doc:`hipBLASLtExt operation API <./reference/ext-ops>`

projects/hipblaslt/docs/reference/env-variables.rst

@@ -0,0 +1,119 @@
+.. meta::
+  :description: hipBLASLt environment variables reference
+  :keywords: hipBLASLt, ROCm, API, environment variables, environment, reference
+
+.. _environment-variables:
+
+********************************************************************
+hipBLASLt environment variables
+********************************************************************
+
+This section describes the important hipBLASLt environment variables,
+which are grouped by functionality.
+
+Logging and debugging
+=====================
+
+The logging and debugging environment variables for hipBLASLt are collected in the following table.
+For more information, see :doc:`Use logging and heuristics <../how-to/use-logging-heuristics>`.
+
+.. list-table::
+    :header-rows: 1
+    :widths: 70,30
+
+    * - **Environment variable**
+      - **Value**
+
+    * - | ``HIPBLASLT_LOG_LEVEL``
+        | Controls the verbosity level of hipBLASLt logging output.
+      - | 0: Off (logging disabled, default)
+        | 1: Error (only errors are logged)
+        | 2: Trace (API calls with kernel launches log parameters)
+        | 3: Hints (performance improvement suggestions)
+        | 4: Info (general library execution information)
+        | 5: API trace (detailed API call parameters)
+
+    * - | ``HIPBLASLT_LOG_MASK``
+        | Controls logging output using bit mask flags (can be combined).
+      - | 0: Off
+        | 1: Error
+        | 2: Trace
+        | 4: Hints
+        | 8: Info
+        | 16: API trace
+        | 32: Bench
+        | 64: Profile
+        | 128: Extended profile
+
+    * - | ``HIPBLASLT_LOG_FILE``
+        | Specifies path to logging file. Can contain ``%i`` for process ID replacement.
+      - | Path to log file (for example, ``logfile_%i.log``)
+        | If not defined: log messages printed to stdout
+
+    * - | ``HIPBLASLT_ENABLE_MARKER``
+        | Enables marker trace for ROCProfiler profiling.
+      - | 0 or unset: Disable marker trace
+        | 1: Enable marker trace
+
+
+Offline tuning
+===============
+
+The offline tuning environment variables for hipBLASLt are collected in the following table.
+For more information, see :doc:`Use hipBLASLt offline tuning <../how-to/how-to-use-hipblaslt-offline-tuning>`.
+
+.. list-table::
+    :header-rows: 1
+    :widths: 70,30
+
+    * - **Environment variable**
+      - **Value**
+
+    * - | ``HIPBLASLT_TUNING_FILE``
+        | Specifies file to store tuning results with best solution indices for GEMM problems.
+      - | Path to tuning file (for example, ``tuning.txt``)
+        | File stores optimal kernel indices for reuse
+
+    * - | ``HIPBLASLT_TUNING_OVERRIDE_FILE``
+        | Specifies file to load tuning results and override default kernel selection.
+      - | Path to tuning file (for example, ``tuning.txt``)
+        | Loads previously saved optimal kernel choices
+
+    * - | ``HIPBLASLT_TUNING_USER_MAX_WORKSPACE``
+        | Sets maximum workspace size constraint during tuning stage.
+      - | Integer value in bytes (default: 128 * 1024 * 1024)
+        | Limits workspace size for solution selection
+
+Stream-K configuration
+======================
+
+The Stream-K configuration environment variables for hipBLASLt are collected in the following table.
+For more information, see :doc:`Use Stream-K with hipBLASLt <../how-to/how-to-use-streamk>`.
+
+.. list-table::
+    :header-rows: 1
+    :widths: 70,30
+
+    * - **Environment variable**
+      - **Value**
+
+    * - | ``TENSILE_SOLUTION_SELECTION_METHOD``
+        | Controls hipBLASLt kernel selection strategy for GEMM operations.
+      - | 0: Default (standard tuned libraries, no Stream-K)
+        | 2: Stream-K (enables Stream-K library for consistent performance)
+
+    * - | ``TENSILE_STREAMK_DYNAMIC_GRID``
+        | Controls Stream-K dynamic grid size selection behavior.
+      - | 0: Disable dynamic grid (use all available compute units)
+        | 3: Default (automatically pick optimal workgroup count)
+
+    * - | ``TENSILE_STREAMK_FIXED_GRID``
+        | Overrides default grid size with specified number of workgroups for Stream-K kernels.
+      - | Integer value specifying number of workgroups
+        | Example: 64 (limits GEMM kernels to 64 workgroups)
+
+    * - | ``TENSILE_STREAMK_MAX_CUS``
+        | Sets maximum number of compute units for Stream-K kernels.
+      - | Integer value specifying maximum compute units
+        | Example: 32 (limits GEMM kernels to 32 compute units)
+        | Default: All available compute units

projects/hipblaslt/docs/sphinx/_toc.yml.in

@@ -47,6 +47,8 @@ subtrees:
   - file: reference/data-type-support
   - file: reference/datatypes
     title: hipBLASLt datatypes
+  - file: reference/env-variables
+    title: hipBLASLt environment variables
   - file: reference/api-reference
     title: hipBLASLt API
   - file: reference/ext-reference