debugability: logger: add note on DMA trace limitations

If sof-logger is started (or restarted) while DSP is running, the initial traces may come in incorrect order or are incomplete. This is important to note when parsing the logger results. BugLink: thesofproject/sof-test#297 Signed-off-by: Kai Vehmanen <[email protected]>
kv2019i · Nov 10, 2021 · c3f2078 · c3f2078
1 parent 9426615
commit c3f2078
Showing 1 changed file with 5 additions and 0 deletions.
diff --git a/developer_guides/debugability/logger/index.rst b/developer_guides/debugability/logger/index.rst
@@ -136,6 +136,11 @@ Examples
     distribution kernels ``sof_debug=1`` module option for ``snd_sof`` might be
     needed if the /sys/kernel/debug/sof/trace file is not present)
 
+.. note::
+  The DMA trace sysfs interface is a streaming interface. If sof-logger is
+  started (or restarted) while DSP is active, it is possible the initial traces
+  messages are in wrong order or incomplete.
+
 Trace filtering
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