tools: Integrate the Dockerfile used for CI
Integrate the Dockerfile from
https://source.denx.de/u-boot/gitlab-ci-runner.git as of
commit bc6130d572f1 ("Dockerfile: Remove high UID/GID") and introduce a
short rST on how to build the container.
Cc: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/doc/build/docker.rst b/doc/build/docker.rst
new file mode 100644
index 0000000..953d1b2
--- /dev/null
+++ b/doc/build/docker.rst
@@ -0,0 +1,14 @@
+GitLab CI / U-Boot runner container
+===================================
+
+In order to have a reproducible and portable build environment for CI we use a container for building in. This means that developers can also reproduce the CI environment, to a large degree at least, locally. This file is located in the tools/docker directory. To build the image yourself
+
+.. code-block:: bash
+
+ sudo docker build -t your-namespace:your-tag .
+
+Or to use an existing container
+
+.. code-block:: bash
+
+ sudo docker pull trini/u-boot-gitlab-ci-runner:bionic-20200807-02Sep2020