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>
OpenRISC GCC supports flags to enable the backend to output instructions
if they are supported by a target processor. This patch adds
configuration flags to enable configuring these flags to tune the kernel
for a particular CPU configuration.
In the future we could also enable all of these flags by default and
provide instruction emulation in the kernel to make these choices easier
for users but this is what we provide for now.
Signed-off-by: Stafford Horne <shorne@gmail.com>
Documentation/kbuild/makefiles.rst suggests to use "archclean" for
cleaning arch/$(SRCARCH)/boot/, but it is not a hard requirement.
Since commit d92cc4d516 ("kbuild: require all architectures to have
arch/$(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/$(SRCARCH)/Makefile. The "archdep"
target no longer exists.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
arch/$(SRCARCH)/Kbuild is useful for Makefile cleanups because you can
use the obj-y syntax.
Add an empty file if it is missing in arch/$(SRCARCH)/.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Describe the subdirectories under arch/openrisc/ in arch/openrisc/Kbuild
so you can use the standard obj-y syntax.
I removed the CONFIG_OPENRISC_BUILTIN_DTB conditional because it is
already controlled by arch/openrisc/boot/dts/Makefile.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Stafford Horne <shorne@gmail.com>
Build it by default. This is commonly used by fpga targets.
Signed-off-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Stafford Horne <shorne@gmail.com>
- LDFLAGS_vmlinux is cleared by the top Makefile
- 'all: vmlinux' is specified by the top Makefile
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Since commit ce99d0bf31 ("kbuild: clear LDFLAGS in the top Makefile"),
the top-level Makefile caters to this.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
The kernel depends on macros like __BYTE_ORDER__,
__BIG_ENDIAN__ or __LITTLE_ENDIAN__.
OTOH, sparse doesn't know about the endianness of the kernel and
by default uses the same as the machine on which sparse was built.
Ensure that sparse can predefine the macros corresponding to
how the kernel was configured by adding -m{big,little}-endian
to CHECKFLAGS in the main Makefile (and so for all archs).
Also, remove the equivalent done in arch specific Makefiles.
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
openrisc is big-endian only but sparse assumes the same endianness
as the building machine.
This is problematic for code which expect __BYTE_ORDER__ being
correctly predefined by the compiler which sparse can then
pre-process differently from what gcc would, depending on the
building machine endianness.
Fix this by letting sparse know about the architecture endianness.
To: Jonas Bonn <jonas@southpole.se>
To: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
To: Stafford Horne <shorne@gmail.com>
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Signed-off-by: Stafford Horne <shorne@gmail.com>
Need append "_D__linux__" to KBUILD_CFLAGS, just like some of another
architectures have done, or 'allmodconfig' can not pass compiling.
The related error:
CC [M] fs/coda/psdev.o
In file included from include/linux/coda.h:65:0,
from fs/coda/psdev.c:45:
include/uapi/linux/coda.h:221:2: error: expected specifier-qualifier-list before 'u_quad_t'
The related compiler information:
[root@dhcp122 ~]# /usr/local/bin/or32-linux-gcc -v
Using built-in specs.
COLLECT_GCC=/usr/local/bin/or32-linux-gcc
COLLECT_LTO_WRAPPER=/usr/local/libexec/gcc/or32-linux/4.5.1-or32-1.0rc1/lto-wrapper
Target: or32-linux
Configured with: ../gcc-openrisc/configure --target=or32-linux --disable-nls --enable-languages=c --without-headers --disable-shared --disable-threads --enable-werror=no
Thread model: single
gcc version 4.5.1-or32-1.0rc1 (GCC)
Signed-off-by: Chen Gang <gang.chen@asianux.com>
Signed-off-by: Jonas Bonn <jonas@southpole.se>
The current rules have the .dtb files build in a different directory
from the .dts files. This patch changes openrisc to use the generic dtb
rule which builds .dtb files in the same directory as the source .dts.
This requires renaming arch/openrisc/boot/Makefile to
arch/openrisc/boot/dts/Makefile, and updating arch/openrisc/Makefile to
call the new Makefile.
Cc: Jonas Bonn <jonas@southpole.se>
Cc: linux@lists.openrisc.net
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Same code. Use the generic version. The special Makefile treatment is
pointless anyway as init_task.o contains only data which is handled by
the linker script. So no point on being treated like head text.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jonas Bonn <jonas@southpole.se>
Link: http://lkml.kernel.org/r/20120503085035.083343435@linutronix.de
