doc: update build system documentation

Split normal build system documentation and the fate one.

Document THREADS make variable and provide an introduction to fate.
Document DESTDIR make variable and add some generic targets.

1 files changed, 45 insertions, 0 deletions

diff --git a/doc/fate.txt b/doc/fate.txt
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+FATE Automated Testing Environment
+
+FATE provides a regression testsuite that can be run locally or configured
+to send reports to fate.libav.org.
+In order to run, it needs a large amount of data (samples and references)
+that is provided separately from the actual source distribution.
+
+Use the following command to get the fate test samples
+
+# rsync -aL rsync://samples.libav.org:/samples/fate-suite/ fate-suite
+
+To inform the build system about the testsuite location, pass
+`--samples=<path to the samples>` to configure or set the SAMPLES Make
+variable or the FATE_SAMPLES environment variable to a suitable value.
+
+For information on how to set up FATE to send results to the official Libav
+testing framework, please refer to the following wiki page:
+http://wiki.multimedia.cx/index.php?title=FATE
+
+FATE Makefile targets:
+
+fate-list
+    Will list all fate/regression test targets.
+
+fate
+    Run the FATE test suite (requires the fate-suite dataset).
+
+Fate Makefile variables:
+
+V
+    Verbosity level, can be set to 0, 1 or 2.
+    * 0: show just the test arguments
+    * 1: show just the command used in the test
+    * 2: show everything
+
+SAMPLES
+    Specify or override the path to the FATE samples at make time, it has a
+    meaning only while running the regression tests.
+
+THREADS
+    Specify how many threads to use while running regression tests, it is
+    quite useful to detect thread-related regressions.
+
+Example:
+    make V=1 SAMPLES=/var/fate/samples THREADS=2 fate