kbuild: remove head-y syntax

Kbuild puts the objects listed in head-y at the head of vmlinux.
Conventionally, we do this for head*.S, which contains the kernel entry
point.

A counter approach is to control the section order by the linker script.
Actually, the code marked as __HEAD goes into the ".head.text" section,
which is placed before the normal ".text" section.

I do not know if both of them are needed. From the build system
perspective, head-y is not mandatory. If you can achieve the proper code
placement by the linker script only, it would be cleaner.

I collected the current head-y objects into head-object-list.txt. It is
a whitelist. My hope is it will be reduced in the long run.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>

nios2: move core-y in arch/nios2/Makefile to arch/nios2/Kbuild

Use obj-y to clean up Makefile.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

kbuild: factor out the common installation code into scripts/install.sh

Many architectures have similar install.sh scripts.

The first half is really generic; it verifies that the kernel image
and System.map exist, then executes ~/bin/${INSTALLKERNEL} or
/sbin/${INSTALLKERNEL} if available.

The second half is kind of arch-specific; it copies the kernel image
and System.map to the destination, but the code is slightly different.

Factor out the generic part into scripts/install.sh.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <n.schier@avm.de>

kbuild: use more subdir- for visiting subdirectories while cleaning

Documentation/kbuild/makefiles.rst suggests to use "archclean" for
cleaning arch/$(SRCARCH)/boot/, but it is not a hard requirement.

Since commit d92cc4d51643 ("kbuild: require all architectures to have
arch/$(SRCARCH)/Kbuild"), we can use the "subdir- += boot" trick for
all architectures. This can take advantage of the parallel option (-j)
for "make clean".

I also cleaned up the comments in arch/$(SRCARCH)/Makefile. The "archdep"
target no longer exists.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)

nios2: move the install rule to arch/nios2/Makefile

Currently, the install target in arch/nios2/Makefile descends into
arch/nios2/boot/Makefile to invoke the shell script, but it is no
good reason to do so.

arch/nios2/Makefile can run the shell script directly.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

kbuild: consolidate Devicetree dtb build rules

There is nothing arch specific about building dtb files other than their
location under /arch/*/boot/dts/. Keeping each arch aligned is a pain.
The dependencies and supported targets are all slightly different.
Also, a cross-compiler for each arch is needed, but really the host
compiler preprocessor is perfectly fine for building dtbs. Move the
build rules to a common location and remove the arch specific ones. This
is done in a single step to avoid warnings about overriding rules.

The build dependencies had been a mixture of 'scripts' and/or 'prepare'.
These pull in several dependencies some of which need a target compiler
(specifically devicetable-offsets.h) and aren't needed to build dtbs.
All that is really needed is dtc, so adjust the dependencies to only be
dtc.

This change enables support 'dtbs_install' on some arches which were
missing the target.

Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Paul Burton <paul.burton@mips.com>
Acked-by: Ley Foon Tan <ley.foon.tan@intel.com>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: linux-kbuild@vger.kernel.org
Cc: linux-snps-arc@lists.infradead.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: uclinux-h8-devel@lists.sourceforge.jp
Cc: linux-mips@linux-mips.org
Cc: nios2-dev@lists.rocketboards.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-xtensa@linux-xtensa.org
Signed-off-by: Rob Herring <robh@kernel.org>

nios2: use common rules to build built-in dtb

Using the common build support for built-in dtb files just requires
adding a .dtb.o target to obj-y.

This has the side effect that CONFIG_NIOS2_DTB_SOURCE should now be just
the dts filename in arch/nios2/boot/dts/ directory. Before any path was
supported, but if you want to build in your dtb to the kernel, it should
be in the kernel tree.

Cc: Ley Foon Tan <lftan@altera.com>
Cc: nios2-dev@lists.rocketboards.org
Signed-off-by: Rob Herring <robh@kernel.org>

nios2: build .dtb files in dts directory

Align nios2 with other architectures which build the dtb files in the
same directory as the dts files. This is also in line with most other
build targets which are located in the same directory as the source.
This move will help enable the 'dtbs' target which builds all the dtbs
regardless of kernel config.

This transition could break some scripts if they expect dtb files in
the old location.

Cc: Ley Foon Tan <lftan@altera.com>
Cc: nios2-dev@lists.rocketboards.org
Signed-off-by: Rob Herring <robh@kernel.org>

nios2: Add CDX support

Add support for the CDX Code Density Extensions present in
Nios II R2 . This introduces new 16bit instruction set to
improve code density while retaining support for the 32bit
Nios II R2 instructions.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Ley Foon Tan <lftan@altera.com>

nios2: Add BMX support

Add support for the BMX Bit Manipulation Extensions present in
Nios II R2 . This introduces three new instructions, EXTRACT,
INSERT and MERGE.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Ley Foon Tan <lftan@altera.com>

nios2: Add NIOS2_ARCH_REVISION to select between R1 and R2

Allow user to select between Nios2 R1 and R2. Since R1 and R2 are
not binary compatible, we cannot have a single kernel binary and
there is no point in having DT property for discerning these two.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Ley Foon Tan <lftan@altera.com>

nios2: Add order-only DTC dependency to %.dtb target

The dtc dependency is missing, thus dtc is not built before it's invoked,
resulting in the following problem:

linux-2.6$ make 10m50_defconfig && make 10m50_devboard.dtb
[...]
scripts/kconfig/conf --silentoldconfig Kconfig
DTC arch/nios2/boot/10m50_devboard.dtb
/bin/sh: 1: ./scripts/dtc/dtc: not found
arch/nios2/boot/Makefile:52: recipe for target 'arch/nios2/boot/10m50_devboard.dtb' failed
make[1]: *** [arch/nios2/boot/10m50_devboard.dtb] Error 127
arch/nios2/Makefile:57: recipe for target '10m50_devboard.dtb' failed
make: *** [10m50_devboard.dtb] Error 2

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Romain Perier <romain.perier@free-electrons.com>
Acked-by: Ley Foon Tan <lftan@altera.com>

nios2: Fix libgcc location detection

The extra CFLAGS required for correct operation of the toolchain are not
propagated into the libgcc detection code. In case of the compiler from
poky sdk, these extra CFLAGS contain the location of compiler sysroot
(the --sysroot= option) and without this option, the location of libgcc
is not properly reported. Add the missing CFLAGS to address this issue.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Romain Perier <romain.perier@free-electrons.com>
Acked-by: Romain Perier <romain.perier@free-electrons.com>
Acked-by: Ley Foon Tan <lftan@altera.com>

nios2: enable "make defconfig"

Running "make defconfig" currently fails for nios2:
$ make ARCH=nios2 defconfig
scripts/kconfig/conf --defconfig Kconfig
***
*** Can't find default configuration "arch/nios2/defconfig"!
***
make[1]: *** [defconfig] Error 1
make: *** [defconfig] Error 2

Add a definition for KBUILD_DEFCONFIG to the nios2's main Makefile to enable
this make target.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Acked-by: Ley Foon Tan <lftan@altera.com>

nios2: Build infrastructure

This patch adds Makefile and Kconfig files required for building a
nios2 kernel.

Signed-off-by: Ley Foon Tan <lftan@altera.com>