arch: add KBUILD_DEFCONFIG to allow "make defconfig" ...

Currently, "make defconfig" is only supported for sandbox and x86.

I set KBUILD_DEFCONFIG to support "make defconfig" where I was able
to find a suitable one.

nios2 and openrisc have a single generic_defconfig, so it is definitely
good for KBUILD_DEFCONFIG.

For arm, mips, I assume qemu is a preferred choice over a real board.

blackfin has only one defconfig. Since it is inactive (it is gone in
Linux), so no more defconfig will come in.

I am not sure about ppc and riscv, so I did not touch them.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Makefile: generate a barebox-flash-image link ...

Depending on the SoC a barebox.bin, barebox.netx, barebox.s5p, MLO image
is generated. With pbl support there now is an additional
arch/arm/pbl/zbarebox.bin image.

To help the user to determine which image should be flashed to his device,
generate a barebox-flash-image link.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>

Only pass -P to cpp when generating ld scripts ...

When building sandbox with ccache, one would hit warnings such as:
    warning: 'struct mmsghdr' declared inside parameter list
on random files; a way to reproduce this issue is to build a simple
file doing just:
    #include <sys/socket.h>

    int main(void) {
        return 0;
    }

    gcc -Wall -P -c -o foo foo.c

But actually the -P flag is only useful when generating non-C files,
such as linker scripts in the case of barebox.  Removing the -P flag
from all the gcc invocations, except when generating .lds files makes
the warning go away.  It turns out that this is what
linux/scripts/Makefile.build also does nowadays.

Signed-off-by: Loïc Minier <loic.minier@linaro.org>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

move boards to arch/<architecure>/boards ...

this will allow each arch to handle the boards more simply and depending on
there need

the env var BOARD will refer to the current board dirent

for sandbox as we have only one board the board dirent is arch/sandbox/board

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

rename U-Boot-v2 project to barebox ...

This has been done with the following script:

find -path ./.git -prune -o -type f -print0 | xargs -0 -r sed -i \
	-e 's/u2boot/barebox/g' \
	-e 's/U2Boot/barebox/g' \
	-e 's/U-boot V2/barebox/g' \
	-e 's/u-boot v2/barebox/g' \
	-e 's/U-Boot V2/barebox/g' \
	-e 's/U-Boot-v2/barebox/g' \
	-e 's/U_BOOT/BAREBOX/g' \
	-e 's/UBOOT/BAREBOX/g' \
	-e 's/uboot/barebox/g' \
	-e 's/u-boot/barebox/g' \
	-e 's/u_boot/barebox/g' \
	-e 's/U-Boot/barebox/g' \
	-e 's/U-boot/barebox/g' \
	-e 's/U-BOOT/barebox/g'

find -path ./.git -prune -o \( -name "*u-boot*" -o -name "*uboot*" -o -name "*u_boot*" \) -print0 | \
	xargs -0 -r rename 's/u[-_]?boot/barebox/'

It needs some manual fixup following in the next patch

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

[BLACKFIN] move include/asm-blackfin to arch/blackfin/include/asm ...

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>

[kbuild] move -pipe from architecture Makefiles to toplevel ...

Makefile

[kbuild] remove -Wall from architecture Makefiles. It's already ...

in toplevel CFLAGS

[kbuild] move -nostdinc from architecture Makefiles to toplevel ...

Makefile

[kbuild] move -ffreestanding from architecture Makefiles to toplevel ...

Makefile

[kbuild] move -fno-builtin from architecture Makefiles to toplevel ...

Makefile

[kbuild] move -Os flag from architecture Makefiles to toplevel ...

Makefile

[kbuild] change architecture Makefiles not to overwrite ...

CFLAGS, instead append them to the existing CFLAGS.
	 Also, remove all double CFLAGS

Enable blackfin boot rom boot modes ...

Signed-Off-By: Enrik Berkhan <Enrik.Berkhan@ge.com>

remove -isystem with empty argument ...

This patch removes the "-isystem $(gccincdir)" from the
arch/*/Makefile because gccindir is empty.

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

don't against link libgcc ...

We don't want to link against libgcc.

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

Linking: Remove linker scripts from (arm based-) boards and add ...

a generic linker script to arch/arm/lib/u-boot.lds.S.
	 If a board wants to overwrite a linker script it can do
	 so using CONFIG_BOARD_LINKER_SCRIPT.
	 There is no generic linker script for ppc and blackfin
	 yet, so still use the board specific one.

add blackfin specific bits for module handling

add -D__blackfin__ to blackfin CFLAGS

initial blackfin support