Thomas reported U-Boot failed to build host tools if libfdt-devel
package is installed because tools include libfdt headers from
/usr/include/ instead of using internal ones.

This commit moves the header code:
  include/libfdt.h         -> include/linux/libfdt.h
  include/libfdt_env.h     -> include/linux/libfdt_env.h

and replaces include directives:
  #include <libfdt.h>      -> #include <linux/libfdt.h>
  #include <libfdt_env.h>  -> #include <linux/libfdt_env.h>

Reported-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

There is tons of code duplication between lib/libfdt/libfdt.h and
scripts/dtc/libfdt/libfdt.h.  Evacuate the U-Boot own code to
include/libfdt.h and remove lib/libfdt/libfdt.h.

For host tools, <libfdt.h> should include scripts/dtc/libfdt/libfdt.h,
which is already suitable for user-space.

For compiling U-Boot, <linux/libfdt.h> should be included because we
need a different libfdt_env.h .

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

The only difference between scripts/dtc/libfdt/fdt_rw.c and
lib/libfdt/fdt_rw.c is fdt_remove_unused_strings().

It is only used by fdtgrep, so we do not need to compile it for U-Boot
image.  Move it to tools/libfdt/fdw_rw.c so that lib/libfdt/fdt_rw.c
can be a wrapper of scripts/dtc/libfdt/fdt_rw.c.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

Now, lib/libfdt/fdt_wip.c is the same as scripts/dtc/libfdt/fdt_wip.c

Change the former to a wrapper of the latter.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

All the other fdt_*_region() functions are located in fdt_region.c,
while only fdt_find_regions() was added to fdt_wip.c, strangely.

Move it to the suitable place.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

lib/libfdt/ and scripts/dtc/libfdt have the same copies for the
followings 6 files:
  fdt.c fdt_addresses.c fdt_empty_tree.c fdt_overlay.c fdt_strerr.c
  fdt_sw.c

Make them a wrapper of scripts/dtc/libfdt/*.  This is exactly what
Linux does to sync libfdt.  In order to make is possible, import
<linux/libfdt.h> and <linux/libfdt_env.h> from Linux 4.14-rc5.

Unfortunately, U-Boot locally modified the following 3 files:
  fdt_ro.c fdt_wip.c fdt_rw.c

The fdt_region.c is U-Boot own file.

I did not touch them in order to avoid unpredictable impact.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Fortunately, U-Boot did not modify libfdt_internal.h locally.

Change it to a wrapper of scripts/dtc/libfdt/fdt.h, which will be
periodically synced with the upstream DTC (or kernel).

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Fortunately, U-Boot did not modify fdt.h locally.

Change it to a wrapper of scripts/dtc/libfdt/fdt.h, which will be
periodically synced with the upstream DTC (or kernel).

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

The pylibfdt is used by dtoc (and, indirectly by binman), but there
is no reason why it must be generated in the tools/ directory.

Recently, U-Boot switched over to the bundled DTC, and the directory
structure under scripts/dtc/ now mirrors the upstream DTC project.
So, scripts/dtc/pylibfdt is the best location.

I also rewrote the Makefile in a cleaner Kbuild style.

The scripts from the upstream have been moved as follows:

  lib/libfdt/pylibfdt/setup.py -> scripts/dtc/pylibfdt/setup.py
  lib/libfdt/pylibfdt/libfdt.i -> scripts/dtc/pylibfdt/libfdt.i_shipped

The .i_shipped is coped to .i during building because the .i must be
located in the objtree when we build it out of tree.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

This patch enables an overlay to refer to a previous overlay's
labels by performing a merge of symbol information at application
time.

In a nutshell it allows an overlay to refer to a symbol that a previous
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.

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

baz.dts
-------

	/dts-v1/;
	/plugin/;
	/ {
		fragment@1 {
			target = <&bar>;
			__overlay__ {
				overlay-2-property;
				baz: baznode {
					baz-property;
				};
			};
		};
	};

	$ dtc -@ -I dts -O dtb -o baz.dtb baz.dts

Applying the overlays:

	$ fdtoverlay -i base.dtb -o target.dtb bar.dtb baz.dtb

Dumping:

	$ fdtdump target.dtb
	/ {
            foonode {
                overlay-1-property;
                foo-property;
                linux,phandle = <0x00000001>;
                phandle = <0x00000001>;
                barnode {
                    overlay-2-property;
                    phandle = <0x00000002>;
                    linux,phandle = <0x00000002>;
                    bar-property;
                    baznode {
                        phandle = <0x00000003>;
                        linux,phandle = <0x00000003>;
                        baz-property;
                    };
                };
            };
            __symbols__ {
                baz = "/foonode/barnode/baznode";
                bar = "/foonode/barnode";
                foo = "/foonode";
            };
	};

Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Simon Glass <sjg@chromium.org>