dm: Add documentation for host command and implementation
Document the 'host' command and also the internals of how it is
implemented.
Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/doc/arch/sandbox/index.rst b/doc/arch/sandbox/index.rst
new file mode 100644
index 0000000..1f1f5de
--- /dev/null
+++ b/doc/arch/sandbox/index.rst
@@ -0,0 +1,12 @@
+.. SPDX-License-Identifier: GPL-2.0+ */
+.. Copyright 2022 Google LLC
+.. sectionauthor:: Simon Glass <sjg@chromium.org>
+
+Sandbox
+=======
+
+.. toctree::
+ :maxdepth: 2
+
+ sandbox
+ block_impl