Prior to Kbuild, $(TOPDIR) or $(SRCTREE) was used for
pointing to the top of source directory.
(No difference between the two.)

In Kbuild style, $(srctree) is used for instead.
This commit renames SRCTREE to srctree and deletes the
defition of SRCTREE.

Note that SRCTREE in scripts/kernel-doc, scripts/docproc.c,
doc/DocBook/Makefile should be keep.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>

LOGO_BMP was never overwritten by board-specific or
vendor-specific logos.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Reported-by: Bo Shen <voice.shen@atmel.com>
Tested-by: Bo Shen <voice.shen@atmel.com>

Programs in tools/ directory are usually built for the host.
But some of them (mkimage, dumpimge, gen_eth_addr, etc.) are
useful on the target OS too.

Actually, prior to Kbuild, U-Boot could build tools for
the target like follows:

  $ make <target_board>_config
  $ export CROSS_COMPILE=<cross_gcc_prefix>
  $ make HOSTCC=${CROSS_COMPILE}gcc HOSTSTRIP=${CROSS_COMPILE}strip tools

In Kbuild, we can no longer replace HOSTCC at the command line.

In order to get back that feature, this commit adds "cross-tools" target.

Usage:

  Build tools for the host
  $ make CROSS_COMPILE=<cross_gcc_prefix> tools

  Build tools for the target
  $ make CROSS_COMPILE=<cross_gcc_prefix> cross_tools

Besides, "make cross_tools" strip tools programs because we
generally expect smaller storages on embedded systems.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Reported-by: Heiko Schocher <hs@denx.de>
Cc: Wolfgang Denk <wd@denx.de>
Cc: Tom Rini <trini@ti.com>
Tested-by: Heiko Schocher <hs@denx.de>
Acked-by: Heiko Schocher <hs@denx.de>

tools/kernel-doc/docproc.c and tools/kernel-doc/kernel-doc are
files imported from Linux Kernel.

They originally resided under scripts/ directory in Linux Kernel.

This commit moves them to the original location.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Acked-by: Simon Glass <sjg@chromium.org>

- Move "easylogo", "gdb" tagets to tools/Makefile
 - Delete "gdbtools" target (same as "gdb")

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>

Now we are ready to switch over to real Kbuild.

This commit disables temporary scripts:
  scripts/{Makefile.build.tmp, Makefile.host.tmp}
and enables real Kbuild scripts:
  scripts/{Makefile.build,Makefile.host,Makefile.lib}.

This switch is triggered by the line in scripts/Kbuild.include
  -build := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.build.tmp obj
  +build := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.build obj

We need to adjust some build scripts for U-Boot.
But smaller amount of modification is preferable.

Additionally, we need to fix compiler flags which are
locally added or removed.

In Kbuild, it is not allowed to change CFLAGS locally.
Instead, ccflags-y, asflags-y, cppflags-y,
CFLAGS_$(basetarget).o, CFLAGS_REMOVE_$(basetarget).o
are prepared for that purpose.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Tested-by: Gerhard Sittig <gsi@denx.de>

This commit changes the working directory
where the build process occurs.

Before this commit, build process occurred under the source
tree for both in-tree and out-of-tree build.

That's why we needed to add $(obj) prefix to all generated
files in makefiles like follows:
  $(obj)u-boot.bin:  $(obj)u-boot

Here, $(obj) is empty for in-tree build, whereas it points
to the output directory for out-of-tree build.

And our old build system changes the current working directory
with "make -C <sub-dir>" syntax when descending into the
sub-directories.

On the other hand, Kbuild uses a different idea
to handle out-of-tree build and directory descending.

The build process of Kbuild always occurs under the output tree.
When "O=dir/to/store/output/files" is given, the build system
changes the current working directory to that directory and
restarts the make.

Kbuild uses "make -f $(srctree)/scripts/Makefile.build obj=<sub-dir>"
syntax for descending into sub-directories.
(We can write it like "make $(obj)=<sub-dir>" with a shorthand.)
This means the current working directory is always the top
of the output directory.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Tested-by: Gerhard Sittig <gsi@denx.de>

This commit merges commonly-used header include paths
to UBOOTINCLUDE and NOSTDINC_FLAGS variables, which are placed
at the top Makefile.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>

Before this commit, makefiles under tools/ directory
were implemented with their own way.

This commit refactors them by using "hostprogs-y" variable.

Several C sources have been added to wrap other C sources
to simplify Makefile.
For example, tools/crc32.c includes lib/crc32.c

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>

The incorrect substitution made it rebuild every time.

Signed-off-by: Ian Campbell <ijc@hellion.org.uk>
Cc: Tom Rini <trini@ti.com>
Acked-by: Simon Glass <sjg@chromium.org>