[U-Boot] [PATCH 22/24] binman: Document parallel tests

[Simon Glass]

Since binman can run tests in parallel, document this.

Signed-off-by: Simon Glass <sjg at chromium.org>
---

 tools/binman/README | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/tools/binman/README b/tools/binman/README
index 927fa856acf..ac193f16cf7 100644
--- a/tools/binman/README
+++ b/tools/binman/README
@@ -702,6 +702,20 @@ To enable Python test coverage on Debian-type distributions (e.g. Ubuntu):
    $ sudo apt-get install python-coverage python-pytest
 
 
+Concurrent tests
+----------------
+
+Binman tries to run tests concurrently. This means that the tests make use of
+all available CPUs to run.
+
+ To enable this:
+
+   $ sudo apt-get install python-subunit python3-subunit
+
+Use '-P 1' to disable this. It is automatically disabled when code coverage is
+being used (-T) since they are incompatible.
+
+
 Advanced Features / Technical docs
 ----------------------------------
 
-- 
2.21.0.1020.gf2820cf01a-goog