doc: move README.fdt-overlays to HTML documentation

Convert doc/README.fdt-overlays to doc/usage/fdt_overlays.rst.

Edit the text for readability.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

1 files changed, 0 insertions, 114 deletions

diff --git a/doc/README.fdt-overlays b/doc/README.fdt-overlays
deleted file mode 100644
index 39139cb850c..00000000000
--- a/doc/README.fdt-overlays
+++ /dev/null
@@ -1,114 +0,0 @@
-U-Boot FDT Overlay usage
-=============================================
-
-Overlays Syntax
----------------
-
-Overlays require slightly different syntax compared to traditional overlays.
-Please refer to dt-object-internal.txt in the dtc sources for information
-regarding the internal format of overlays:
-https://git.kernel.org/pub/scm/utils/dtc/dtc.git/tree/Documentation/dt-object-internal.txt
-
-Building Overlays
------------------
-
-In a nutshell overlays provides a means to manipulate a symbol a previous dtb
-or overlay has defined. It requires both the base and all the overlays
-to be compiled with the -@ command line switch so that symbol information is
-included.
-
-Note support for -@ option can only be found in dtc version 1.4.4 or newer.
-Only version 4.14 or higher of the Linux kernel includes a built in version
-of dtc that meets this requirement.
-
-Building an overlay follows the same process as building a traditional dtb.
-
-For example:
-
-base.dts
---------
-
-	/dts-v1/;
-	/ {
-		foo: foonode {
-			foo-property;
-		};
-	};
-
-	$ dtc -@ -I dts -O dtb -o base.dtb base.dts
-
-bar.dts
--------
-
-	/dts-v1/;
-	/plugin/;
-	/ {
-		fragment@1 {
-			target = <&foo>;
-			__overlay__ {
-				overlay-1-property;
-				bar: barnode {
-					bar-property;
-				};
-			};
-		};
-	};
-
-	$ dtc -@ -I dts -O dtb -o bar.dtb bar.dts
-
-Ways to Utilize Overlays in U-boot
-----------------------------------
-
-There are two ways to apply overlays in U-boot.
-1. Include and define overlays within a FIT image and have overlays
-   automatically applied.
-
-2. Manually load and apply overlays
-
-The remainder of this document will discuss using overlays via the manual
-approach. For information on using overlays as part of a FIT image please see:
-doc/uImage.FIT/overlay-fdt-boot.txt
-
-Manually Loading and Applying Overlays
---------------------------------------
-
-1. Figure out where to place both the base device tree blob and the
-overlay. Make sure you have enough space to grow the base tree without
-overlapping anything.
-
-=> setenv fdtaddr 0x87f00000
-=> setenv fdtovaddr 0x87fc0000
-
-2. Load the base blob and overlay blobs
-
-=> load ${devtype} ${bootpart} ${fdtaddr} ${bootdir}/base.dtb
-=> load ${devtype} ${bootpart} ${fdtovaddr} ${bootdir}/overlay.dtb
-
-3. Set it as the working fdt tree.
-
-=> fdtaddr $fdtaddr
-
-4. Grow it enough so it can 'fit' all the applied overlays
-
-=> fdt resize 8192
-
-5. You are now ready to apply the overlay.
-
-=> fdt apply $fdtovaddr
-
-6. Boot system like you would do with a traditional dtb.
-
-For bootm:
-
-=> bootm ${kerneladdr} - ${fdtaddr}
-
-For bootz:
-
-=> bootz ${kerneladdr} - ${fdtaddr}
-
-Please note that in case of an error, both the base and overlays are going
-to be invalidated, so keep copies to avoid reloading.
-
-Pantelis Antoniou
-pantelis.antoniou@konsulko.com
-11/7/2017