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Diffstat (limited to 'Documentation/devicetree/of_unittest.rst')
-rw-r--r-- | Documentation/devicetree/of_unittest.rst | 27 |
1 files changed, 24 insertions, 3 deletions
diff --git a/Documentation/devicetree/of_unittest.rst b/Documentation/devicetree/of_unittest.rst index 2afe41a37148..8864b52d1195 100644 --- a/Documentation/devicetree/of_unittest.rst +++ b/Documentation/devicetree/of_unittest.rst @@ -24,7 +24,28 @@ from the unflattened device tree data structure. This interface is used by most of the device drivers in various use cases. -2. Test-data +2. Verbose Output (EXPECT) +========================== + +If unittest detects a problem it will print a warning or error message to +the console. Unittest also triggers warning and error messages from other +kernel code as a result of intentionally bad unittest data. This has led +to confusion as to whether the triggered messages are an expected result +of a test or whether there is a real problem that is independent of unittest. + +'EXPECT \ : text' (begin) and 'EXPECT / : text' (end) messages have been +added to unittest to report that a warning or error is expected. The +begin is printed before triggering the warning or error, and the end is +printed after triggering the warning or error. + +The EXPECT messages result in very noisy console messages that are difficult +to read. The script scripts/dtc/of_unittest_expect was created to filter +this verbosity and highlight mismatches between triggered warnings and +errors vs expected warnings and errors. More information is available +from 'scripts/dtc/of_unittest_expect --help'. + + +3. Test-data ============ The Device Tree Source file (drivers/of/unittest-data/testcases.dts) contains @@ -56,7 +77,7 @@ The assembly file is compiled into an object file (testcases.dtb.o), and is linked into the kernel image. -2.1. Adding the test data +3.1. Adding the test data ------------------------- Un-flattened device tree structure: @@ -191,7 +212,7 @@ properties are updated to the live tree's node by calling the function update_node_properties(). -2.2. Removing the test data +3.2. Removing the test data --------------------------- Once the test case execution is complete, selftest_data_remove is called in |