This commit imports some updates in misc scripts from Linux 3.18-rc1.

[1] commit cbb4d3e6510b99522719c5ef0 by Horia Geanta
scripts/kernel-doc: handle object-like macros

[2] commit 164f0d2efaaef83 by Michal Marek
kbuild: Fix handling of backslashes in *.cmd files

[3] commit 270a00963cd367214e by Randy Dunlap
scripts/kernel-doc: recognize __meminit

[4] commit a4954fd7724c0f55361eb5 by Masahiro Yamada
  kbuild: remove obj-n and lib-n handling

[5] commit 5b2389b45d1a9c12b9f by Masahiro Yamada
kbuild: simplify build, clean, modbuiltin shorthands

Signed-off-by: Horia Geanta <horia.geanta@freescale.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>

Since Linux 3.18-rc1, Kbuild is able to handle multi-objs
dependency correctly, which also allows us futher cleanups
of some makefiles.

This commit imports those commits:

[1] commit c8589d1e9e01 by Masahiro Yamada
kbuild: handle multi-objs dependency appropriately

[2] commit 97e3226e6e98 by Masahiro Yamada
kbuild: handle the dependency of multi-objs hostprogs appropriately

[3] commit 022af62d0190 by Masahiro Yamada
kbuild: refactor script/kconfig/Makefile

[4] commit 221ecca6cafe by Masahiro Yamada
kbuild: remove redundant clean-files from scripts/kconfig/Makefile

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

This commit was imported from Linux Kernel:
commit a86fe353 written by me.

W=... provides extra gcc checks.

Having such code in scripts/Makefile.build results in the same flags
being added to KBUILD_CFLAGS multiple times becuase
scripts/Makefile.build is invoked every time Kbuild descends into
the subdirectories.

Since the top Makefile is already too cluttered, this commit moves
all of extra gcc check stuff to a new file scripts/Makefile.extrawarn,
which is included from the top Makefile.

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

This commit enables Kconfig.
Going forward, we use Kconfig for the board configuration.
mkconfig will never be used. Nor will include/config.mk be generated.

Kconfig must be adjusted for U-Boot because our situation is
a little more complicated than Linux Kernel.
We have to generate multiple boot images (Normal, SPL, TPL)
from one source tree.
Each image needs its own configuration input.

Usage:

Run "make <board>_defconfig" to do the board configuration.

It will create the .config file and additionally spl/.config, tpl/.config
if SPL, TPL is enabled, respectively.

You can use "make config", "make menuconfig" etc. to create
a new .config or modify the existing one.

Use "make spl/config", "make spl/menuconfig" etc. for spl/.config
and do likewise for tpl/.config file.

The generic syntax of configuration targets for SPL, TPL is:

  <target_image>/<config_command>

Here, <target_image> is either 'spl' or 'tpl'
      <config_command> is 'config', 'menuconfig', 'xconfig', etc.

When the configuration is done, run "make".
(Or "make <board>_defconfig all" will do the configuration and build
in one time.)

For futher information of how Kconfig works in U-Boot,
please read the comment block of scripts/multiconfig.py.

By the way, there is another item worth remarking here:
coexistence of Kconfig and board herder files.

Prior to Kconfig, we used C headers to define a set of configs.

We expect a very long term to migrate from C headers to Kconfig.
Two different infractructure must coexist in the interim.

In our former configuration scheme, include/autoconf.mk was generated
for use in makefiles.
It is still generated under include/, spl/include/, tpl/include/ directory
for the Normal, SPL, TPL image, respectively.

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

Import the following trivial commits from Linux v3.16-rc1:

 bb66fc6 kbuild: trivial - use tabs for code indent where possible
 7eb6e34 kbuild: trivial - remove trailing empty lines
 3fbb43d kbuild: trivial - fix comment block indent
 38385f8 kbuild: trivial - remove trailing spaces

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

This commit imports Kbuild-related updates
from v3.14 to v3.15-rc1.

 - commit 3d3d6b8474204b6819688c9800774d52d370a538
    kbuild: LLVMLinux: Adapt warnings for compilation with clang
 - commit 61163efae02040f66a95c8ed17f4407951ba58fa
    kbuild: LLVMLinux: Add Kbuild support for building kernel with Clang
 - commit 79192ca8ebd9a25c583aa46024a250fef1e7766f
    scripts: objdiff: detect object code changes between two commits
 - commit 1c9e70a55b088d97a59241744fe459409d0c3582
    kbuild: create a build directory automatically for out-of-tree build
 - commit a03fcb50e816a69acffb13b5e56db75063aeba8a
    kbuild: remove redundant '.*.cmd' pattern from make distclean
 - commit 13338935f1574a2dcd1c891461b0dcc42f8cff42
    kbuild: move "quote" to Kbuild.include to be consistent
 - commit bfdfaeae500a3b194b73b01e92a8034791a58b7f
    kbuild: specify build_docproc as a phony target
 - commit f4d4ffc03efc864645b990e1d579bbe1b8e358a4
    kbuild: dtbs_install: new make target
 - commit 1e64ff42ea3d8d2fc8aa71f9717b3c1cb6c2f893
    Kbuild, lto: Disable LTO for asm-offsets.c
 - commit ccbef1674a1579842c7dbdf554efca85d2cd245a
    Kbuild, lto: add ld-version and ld-ifversion macros
 - commit ae63b2d7bdd9bd66b88843be0daf8e37d8f0b574
    scripts/tags.sh: Ignore *.mod.c
 - commit e36aaea28972c57a32a3ba5365e61633739719b9
    kbuild: Fix silent builds with make-4

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

Kbuild brought about many advantages for us but a significant
performance regression was reported by Simon Glass.

After some discussions and analysis, it turned out
its main cause is in $(call cc-option,...).

Historically, U-Boot parses all config.mk
(arch/*/config.mk and board/*/config.mk)
every time descending into subdirectories.
That means cc-options are evaluated over and over again.

$(call cc-option,...) is useful but costly.
So we want to evaluate them only in ./Makefile
and spl/Makefile and export compiler flags.

This commit changes the build system as follows:

  - Modify scripts/Makefile.build to not include config.mk
    Instead, add $(PLATFORM_CPPFLAGS) to asflags-y, ccflags-y,
    cppflags-y.

  - Export many variables
    Going forward, Kbuild will not parse config.mk files
    when it descends into subdirectories.
    If we want to set variables in config.mk and use them
    in subdirectories, they must be exported.

    This is the list of variables to get exported:
      PLATFORM_CPPFLAGS
      CPUDIR
      BOARDDIR
      OBJCOPYFLAGS
      LDFLAGS
      LDFLAGS_FINAL
        (used in nand_spl/board/*/*/Makefile)
      CONFIG_STANDALONE_LOAD_ADDR
        (used in examples/standalone/Makefile)
      SYM_PREFIX
        (used in examples/standalone/Makefile)
      RELFLAGS
        (used in examples/standalone/Makefile)

  - Delete CPPFLAGS
    This variable has been replaced with PLATFORM_CPPFLAGS

  - Copy gcclibdir from example/standalone/Makefile
    to arch/sparc/config.mk
    The reference in CONFIG_STANDALONE_LOAD_ADDR must be
    resolved before it is exported.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Reported-by: Simon Glass <sjg@chromium.org>
Acked-by: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org> [on Sandbox]
Tested-by: Stephen Warren <swarren@nvidia.com> [on Tegra]

This commit changes the location of include directives
of board configuration files.

The purpose of this change is:
 - Slim down $(TOPDIR)/config.mk
 - Prevent $(TOPDIR)/Makefile from including the same
    configuration file twice
 - Do not include include/config.mk multiple times
    because ARCH, CPU, BOARD, VENDOR, SOC are exported

Before this commit:

 - include/autoconf.mk was included from $(TOPDIR)/Makefile
   and $(TOPDIR)/config.mk
   (This means $(TOPDIR)/Makefile included include/autoconf.mk twice)

 - include/{spl,tpl}-autoconf.mk was included from $(TOPDIR)/config.mk

 - include/config.mk was included from $(TOPDIR)/Makefile
   and $(TOPDIR)/config.mk
   (This means $(TOPDIR)/Makefile included include/config.mk twice)

After this commit:

 - include/autoconf.mk is included from $(TOPDIR)/Makefile
   and $(TOPDIR)/scripts/Makefile.build

 - include/{spl,tpl}-autoconf.mk is included from $(TOPDIR)/spl/Makefile
   and $(TOPDIR)/scripts/Makefile.build

 - include/config.mk is included from $(TOPDIR)/config.mk and
   $(TOPDIR)/spl/Makefile

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 imports build scripts from Linux Kernel v3.13
as they are.

I know they include some trailing spaces
but I am intentionally keeping them untouched.

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