doc: Move devicetree control doc to rST

Move this to rST format, largely unchanged to start with. Add an index
for this topic, as well as an empty intro.

Note this patch does not include updates! Is it just a conversion to the
new format. See the next patch.
Signed-off-by: NSimon Glass <sjg@chromium.org>
Reviewed-by: NHeinrich Schuchart <xypron.glpk@gmx.de>

doc/README.fdt-control → doc/develop/devicetree/control.rst

-# SPDX-License-Identifier: GPL-2.0+
-#
-# Copyright (c) 2011 The Chromium OS Authors.
+.. SPDX-License-Identifier: GPL-2.0+
+.. sectionauthor:: Copyright 2011 The Chromium OS Authors
 
 Device Tree Control in U-Boot
 =============================
@@ -37,9 +36,7 @@ What is a Flat Device Tree?
 ---------------------------
 
 An fdt can be specified in source format as a text file. To read about
-the fdt syntax, take a look at the specification here:
-
-https://www.power.org/resources/downloads/Power_ePAPR_APPROVED_v1.0.pdf
+the fdt syntax, take a look at the specification (dtspec_).
 
 You also might find this section of the Linux kernel documentation
 useful: (access this in the Linux kernel source code)
@@ -60,18 +57,18 @@ To use this feature you will need to get the device tree compiler. This is
 provided by U-Boot automatically. If you have a system version of dtc
 (typically in the 'device-tree-compiler' package), it is currently not used.
 
-If you want to build your own dtc, it is kept here:
+If you want to build your own dtc, it is kept here::
 
 	git://git.kernel.org/pub/scm/utils/dtc/dtc.git
 
-For example:
+For example::
 
 	$ git clone git://git.kernel.org/pub/scm/utils/dtc/dtc.git
 	$ cd dtc
 	$ make
 	$ sudo make install
 
-Then run the compiler (your version will vary):
+Then run the compiler (your version will vary)::
 
 	$ dtc -v
 	Version: DTC 1.2.0-g2cb4b51f
@@ -105,14 +102,14 @@ Failing that, you could write one from scratch yourself!
 Configuration
 -------------
 
-Use:
+Use::
 
-#define CONFIG_DEFAULT_DEVICE_TREE	"<name>"
+   #define CONFIG_DEFAULT_DEVICE_TREE	"<name>"
 
 to set the filename of the device tree source. Then put your device tree
-file into
+file into::
 
-	board/<vendor>/dts/<name>.dts
+   board/<vendor>/dts/<name>.dts
 
 This should include your CPU or SOC's device tree file, placed in
 arch/<arch>/dts, and then make any adjustments required.
@@ -123,9 +120,9 @@ and development only and is not recommended for production devices.
 
 If CONFIG_OF_SEPARATE is defined, then it will be built and placed in
 a u-boot.dtb file alongside u-boot-nodtb.bin. A common approach is then to
-join the two:
+join the two::
 
-	cat u-boot-nodtb.bin u-boot.dtb >image.bin
+   cat u-boot-nodtb.bin u-boot.dtb >image.bin
 
 and then flash image.bin onto your board. Note that U-Boot creates
 u-boot-dtb.bin which does the above step for you also. Resulting
@@ -144,9 +141,9 @@ specify the file to read.
 You cannot use more than one of these options at the same time.
 
 To use a device tree file that you have compiled yourself, pass
-EXT_DTB=<filename> to 'make', as in:
+EXT_DTB=<filename> to 'make', as in::
 
-	make EXT_DTB=boot/am335x-boneblack-pubkey.dtb
+   make EXT_DTB=boot/am335x-boneblack-pubkey.dtb
 
 Then U-Boot will copy that file to u-boot.dtb, put it in the .img file
 if used, and u-boot-dtb.bin.
@@ -162,16 +159,21 @@ variable will be set to the address of the newly relocated fdt blob.
 It is read-only and cannot be changed. It can optionally be used to
 control the boot process of Linux with bootm/bootz commands.
 
-To use this, put something like this in your board header file:
+To use this, put something like this in your board header file::
 
-#define CONFIG_EXTRA_ENV_SETTINGS	"fdtcontroladdr=10000\0"
+   #define CONFIG_EXTRA_ENV_SETTINGS	"fdtcontroladdr=10000\0"
 
 Build:
 
-After board configuration is done, fdt supported u-boot can be build in two ways:
-1)  build the default dts which is defined from CONFIG_DEFAULT_DEVICE_TREE
+After board configuration is done, fdt supported u-boot can be build in two
+ways:
+
+#  build the default dts which is defined from CONFIG_DEFAULT_DEVICE_TREE::
+
     $ make
-2)  build the user specified dts file
+
+#  build the user specified dts file::
+
     $ make DEVICE_TREE=<dts-file-name>
 
 
@@ -225,6 +227,4 @@ but can use the fdt to specific the UART clock, peripheral address, etc.
 In very broad terms, the CONFIG options in general control *what* driver
 files are pulled in, and the fdt controls *how* those files work.
 
---
-Simon Glass <sjg@chromium.org>
-1-Sep-11
+.. _dtspec: https://www.power.org/resources/downloads/Power_ePAPR_APPROVED_v1.0.pdf

doc/develop/devicetree/index.rst

+.. SPDX-License-Identifier: GPL-2.0+
+
+Devicetree in U-Boot
+====================
+
+The following holds information on how U-Boot makes use of devicetree for
+build-time and runtime configuration.
+
+.. toctree::
+   :maxdepth: 2
+
+   intro
+   control

doc/develop/devicetree/intro.rst

+.. SPDX-License-Identifier: GPL-2.0+
+
+Devicetree Introduction
+=======================

doc/develop/index.rst

@@ -11,6 +11,7 @@ Implementation
 
    ci_testing
    commands
+   devicetree/index
    driver-model/index
    global_data
    logging