Merge branch 'for-next/metadata'

Conflicts:
	arch/arm/dts/Makefile
	common/Makefile
	lib/Makefile

3 files changed, 58 insertions, 0 deletions

diff --git a/Documentation/user/imd.rst b/Documentation/user/imd.rst
new file mode 100644
index 0000000000..e0251d644e
--- /dev/null
+++ b/Documentation/user/imd.rst
@@ -0,0 +1,54 @@
+
+.. _imd:
+
+Image MetaData (IMD)
+====================
+
+barebox images can be enriched with metadata. This is useful to get information
+the board an image is compiled for and which barebox version an image contains.
+
+There are predefined tags for:
+
+- The build timestamp
+- The barebox release version
+- The model (board) the image is compiled for
+- The toplevel device tree compatible properties the image can handle
+
+Additionally there is a generic key/value tag to add information which does not
+fit into the above categories, for example the memory size for boards which come
+with different memory sizes which can't be automatically detected.
+
+The informations can be extracted with the ``bareboximd`` tool which lives under
+``scripts/`` in the barebox sourcecode. If enabled it is compiled for the compile
+host and also for the target architecture. barebox itself has the :ref:`command_imd`
+command to extract the informations. Here is an example output of the tool called
+without additional options::
+
+  # imd barebox-phytec-pbab01dl-1gib.img
+  build: #890 Wed Jul 30 16:15:24 CEST 2014
+  release: 2014.07.0-00167-ge6632a9-dirty
+  parameter: memsize=1024
+  of_compatible: phytec,imx6x-pbab01 phytec,imx6dl-pfla02 fsl,imx6dl
+  model: Phytec phyFLEX-i.MX6 Duallite Carrier-Board
+
+Single informations can be extracted with the ``-t <type>`` option::
+
+  # imd barebox-phytec-pbab01dl-1gib.img -t release
+  2014.07.0-00167-ge6632a9-dirty
+
+Since the barebox hush does not have output redirection the barebox too has the
+``-s <var>`` option to assign the output to a variable for later evaluation.
+
+Limitations
+-----------
+
+The IMD tags are generated in the barebox binary before a SoC specific image is
+generated. Some SoCs encrypt or otherwise manipulate the images in a way that the
+IMD information is lost. The IMD mechanism does not work on these SoCs. A known
+example is the Freescale i.MX28.
+
+IMD and barebox_update
+----------------------
+
+The IMD informations could well be used to check if an image is suitable for updating
+barebox for a particular board. Support for such a check is planned but not yet implemented.
diff --git a/Documentation/user/updating.rst b/Documentation/user/updating.rst
index 2a963b6200..6a1a73348c 100644
--- a/Documentation/user/updating.rst
+++ b/Documentation/user/updating.rst
@@ -27,3 +27,6 @@ barebox has been started from is registered as default (marked with a ``*``)::
 available for your board. It is recommended to implement it, but you can also
 update barebox manually using :ref:`command_erase` and :ref:`command_cp`
 commands. The exact commands are board specific.
+
+**NOTE** barebox images can be enriched with metadata which can be used to check
+if a given image is suitable for updating barebox, see :ref:`imd`.
diff --git a/Documentation/user/user-manual.rst b/Documentation/user/user-manual.rst
index 0eac0aadc7..3d68bbb9ae 100644
--- a/Documentation/user/user-manual.rst
+++ b/Documentation/user/user-manual.rst
@@ -19,6 +19,7 @@ Contents:
    hush
    defaultenv-2
    updating
+   imd
    devicetree
    pbl
    multi-image