xref: /openbmc/qemu/docs/devel/acpi-bits.rst (revision ffe98631)
1=============================================================================
2ACPI/SMBIOS avocado tests using biosbits
3=============================================================================
4
5Biosbits is a software written by Josh Triplett that can be downloaded
6from https://biosbits.org/. The github codebase can be found
7`here <https://github.com/biosbits/bits/tree/master>`__. It is a software that executes
8the bios components such as acpi and smbios tables directly through acpica
9bios interpreter (a freely available C based library written by Intel,
10downloadable from https://acpica.org/ and is included with biosbits) without an
11operating system getting involved in between.
12There are several advantages to directly testing the bios in a real physical
13machine or VM as opposed to indirectly discovering bios issues through the
14operating system. For one thing, the OSes tend to hide bios problems from the
15end user. The other is that we have more control of what we wanted to test
16and how by directly using acpica interpreter on top of the bios on a running
17system. More details on the inspiration for developing biosbits and its real
18life uses can be found in [#a]_ and [#b]_.
19For QEMU, we maintain a fork of bios bits in gitlab along with all the
20dependent submodules here: https://gitlab.com/qemu-project/biosbits-bits
21This fork contains numerous fixes, a newer acpica and changes specific to
22running this avocado QEMU tests using bits. The author of this document
23is the sole maintainer of the QEMU fork of bios bits repo.
24
25Under the directory ``tests/avocado/``, ``acpi-bits.py`` is a QEMU avocado
26test that drives all this.
27
28A brief description of the various test files follows.
29
30Under ``tests/avocado/`` as the root we have:
31
32::
33
34   ├── acpi-bits
35   │ ├── bits-config
36   │ │ └── bits-cfg.txt
37   │ ├── bits-tests
38   │   ├── smbios.py2
39   │   ├── testacpi.py2
40   │   └── testcpuid.py2
41   ├── acpi-bits.py
42
43* ``tests/avocado``:
44
45   ``acpi-bits.py``:
46   This is the main python avocado test script that generates a
47   biosbits iso. It then spawns a QEMU VM with it, collects the log and reports
48   test failures. This is the script one would be interested in if they wanted
49   to add or change some component of the log parsing, add a new command line
50   to alter how QEMU is spawned etc. Test writers typically would not need to
51   modify this script unless they wanted to enhance or change the log parsing
52   for their tests. In order to enable debugging, you can set **V=1**
53   environment variable. This enables verbose mode for the test and also dumps
54   the entire log from bios bits and more information in case failure happens.
55   You can also set **BITS_DEBUG=1** to turn on debug mode. It will enable
56   verbose logs and also retain the temporary work directory the test used for
57   you to inspect and run the specific commands manually.
58
59   In order to run this test, please perform the following steps from the QEMU
60   build directory:
61   ::
62
63     $ make check-venv (needed only the first time to create the venv)
64     $ ./tests/venv/bin/avocado run -t acpi tests/avocado
65
66   The above will run all acpi avocado tests including this one.
67   In order to run the individual tests, perform the following:
68   ::
69
70     $ ./tests/venv/bin/avocado run tests/avocado/acpi-bits.py --tap -
71
72   The above will produce output in tap format. You can omit "--tap -" in the
73   end and it will produce output like the following:
74   ::
75
76      $ ./tests/venv/bin/avocado run tests/avocado/acpi-bits.py
77      Fetching asset from tests/avocado/acpi-bits.py:AcpiBitsTest.test_acpi_smbios_bits
78      JOB ID     : eab225724da7b64c012c65705dc2fa14ab1defef
79      JOB LOG    : /home/anisinha/avocado/job-results/job-2022-10-10T17.58-eab2257/job.log
80      (1/1) tests/avocado/acpi-bits.py:AcpiBitsTest.test_acpi_smbios_bits: PASS (33.09 s)
81      RESULTS    : PASS 1 | ERROR 0 | FAIL 0 | SKIP 0 | WARN 0 | INTERRUPT 0 | CANCEL 0
82      JOB TIME   : 39.22 s
83
84   You can inspect the log file for more information about the run or in order
85   to diagnoze issues. If you pass V=1 in the environment, more diagnostic logs
86   would be found in the test log.
87
88* ``tests/avocado/acpi-bits/bits-config``:
89
90   This location contains biosbits configuration files that determine how the
91   software runs the tests.
92
93   ``bits-config.txt``:
94   This is the biosbits config file that determines what tests
95   or actions are performed by bits. The description of the config options are
96   provided in the file itself.
97
98* ``tests/avocado/acpi-bits/bits-tests``:
99
100   This directory contains biosbits python based tests that are run from within
101   the biosbits environment in the spawned VM. New additions of test cases can
102   be made in the appropriate test file. For example, new acpi tests can go
103   into testacpi.py2 and one would call testsuite.add_test() to register the new
104   test so that it gets executed as a part of the ACPI tests.
105   It might be occasionally necessary to disable some subtests or add a new
106   test that belongs to a test suite not already present in this directory. To
107   do this, please clone the bits source from
108   https://gitlab.com/qemu-project/biosbits-bits/-/tree/qemu-bits.
109   Note that this is the "qemu-bits" branch and not the "bits" branch of the
110   repository. "qemu-bits" is the branch where we have made all the QEMU
111   specific enhancements and we must use the source from this branch only.
112   Copy the test suite/script that needs modification (addition of new tests
113   or disabling them) from python directory into this directory. For
114   example, in order to change cpuid related tests, copy the following
115   file into this directory and rename it with .py2 extension:
116   https://gitlab.com/qemu-project/biosbits-bits/-/blob/qemu-bits/python/testcpuid.py
117   Then make your additions and changes here. Therefore, the steps are:
118
119       (a) Copy unmodified test script to this directory from bits source.
120       (b) Add a SPDX license header.
121       (c) Perform modifications to the test.
122
123   Commits (a), (b) and (c) should go under separate commits so that the original
124   test script and the changes we have made are separated and clear.
125
126   The test framework will then use your modified test script to run the test.
127   No further changes would be needed. Please check the logs to make sure that
128   appropriate changes have taken effect.
129
130   The tests have an extension .py2 in order to indicate that:
131
132   (a) They are python2.7 based scripts and not python 3 scripts.
133   (b) They are run from within the bios bits VM and is not subjected to QEMU
134       build/test python script maintenance and dependency resolutions.
135   (c) They need not be loaded by avocado framework when running tests.
136
137
138Author: Ani Sinha <ani@anisinha.ca>
139
140References:
141-----------
142.. [#a] https://blog.linuxplumbersconf.org/2011/ocw/system/presentations/867/original/bits.pdf
143.. [#b] https://www.youtube.com/watch?v=36QIepyUuhg
144
145