linux.git/arch/mips/Makefile, branch v4.13

MIPS: Set ISA bit in entry-y for microMIPS kernels

2017-08-08T12:00:50+00:00

When building a kernel for the microMIPS ISA, ensure that the ISA bit
(ie. bit 0) in the entry address is set. Otherwise we may include an
entry address in images which bootloaders will jump to as MIPS32 code.

I originally tried using "objdump -f" to obtain the entry address, which
works for microMIPS but it always outputs a 32 bit address for a 32 bit
ELF whilst nm will sign extend to 64 bit. That matters for systems where
we might want to run a MIPS32 kernel on a MIPS64 CPU & load it with a
MIPS64 bootloader, which would then jump to a non-canonical
(non-sign-extended) address.

This works in all cases as it only changes the behaviour for microMIPS
kernels, but isn't the prettiest solution. A possible alternative would
be to write a custom tool to just extract, sign extend & print the entry
point of an ELF executable. I'm open to feedback if that would be
preferred.

Signed-off-by: Paul Burton 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16950/
Signed-off-by: Ralf Baechle

MIPS: build: Fix "-modd-spreg" switch usage when compiling for mips32r6

2017-06-29T00:42:23+00:00

Add "-modd-spreg" when compiling the kernel for mips32r6 target.

This makes sure the kernel builds properly even with toolchains that
use "-mno-odd-spreg" by default. This is the case with Android gcc.
Prior to this patch, kernel builds using gcc for Android failed with
following error messages, if target architecture is set to mips32r6:

arch/mips/kernel/r4k_switch.S: Assembler messages:
.../r4k_switch.S:210: Error: float register should be even, was 1
.../r4k_switch.S:212: Error: float register should be even, was 3
.../r4k_switch.S:214: Error: float register should be even, was 5
.../r4k_switch.S:216: Error: float register should be even, was 7
.../r4k_switch.S:218: Error: float register should be even, was 9
.../r4k_switch.S:220: Error: float register should be even, was 11
.../r4k_switch.S:222: Error: float register should be even, was 13
.../r4k_switch.S:224: Error: float register should be even, was 15
.../r4k_switch.S:226: Error: float register should be even, was 17
.../r4k_switch.S:228: Error: float register should be even, was 19
.../r4k_switch.S:230: Error: float register should be even, was 21
.../r4k_switch.S:232: Error: float register should be even, was 23
.../r4k_switch.S:234: Error: float register should be even, was 25
.../r4k_switch.S:236: Error: float register should be even, was 27
.../r4k_switch.S:238: Error: float register should be even, was 29
.../r4k_switch.S:240: Error: float register should be even, was 31
make[2]: *** [arch/mips/kernel/r4k_switch.o] Error 1

Signed-off-by: Miodrag Dinic 
Signed-off-by: Goran Ferenc 
Signed-off-by: Aleksandar Markovic 
Cc: James.Hogan@imgtec.com
Cc: Paul.Burton@imgtec.com
Cc: Raghu.Gandham@imgtec.com
Cc: Leonid.Yegoshin@imgtec.com
Cc: Douglas.Leung@imgtec.com
Cc: Petar.Jovanovic@imgtec.com
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16509/
Signed-off-by: Ralf Baechle

MIPS: generic: fix out-of-tree defconfig target builds

2017-04-11T11:17:31+00:00

When specifying a generic defconfig target with O=... option set, make
is invoked in the output location before a target makefile wrapper is
created. Ensure that the correct makefile is used by specifying the
kernel source makefile during make invocation.

This fixes the either of the following errors:

$ make sead3_defoncifg ARCH=mips O=test
make[1]: Entering directory '/mnt/ssd/MIPS/linux-next/test'
make[2]: *** No rule to make target '32r2el_defconfig'.  Stop.
arch/mips/Makefile:506: recipe for target 'sead3_defconfig' failed
make[1]: *** [sead3_defconfig] Error 2
make[1]: Leaving directory '/mnt/ssd/MIPS/linux-next/test'
Makefile:152: recipe for target 'sub-make' failed
make: *** [sub-make] Error 2

$ make 32r2el_defconfig ARCH=mips O=test
make[1]: Entering directory '/mnt/ssd/MIPS/linux-next/test'
Using ../arch/mips/configs/generic_defconfig as base
Merging ../arch/mips/configs/generic/32r2.config
Merging ../arch/mips/configs/generic/el.config
Merging ../arch/mips/configs/generic/board-sead-3.config
!
! merged configuration written to .config (needs make)
!
make[2]: *** No rule to make target 'olddefconfig'.  Stop.
arch/mips/Makefile:489: recipe for target '32r2el_defconfig' failed
make[1]: *** [32r2el_defconfig] Error 2
make[1]: Leaving directory '/mnt/ssd/MIPS/linux-next/test'
Makefile:152: recipe for target 'sub-make' failed
make: *** [sub-make] Error 2

Fixes: eed0eabd12ef ('MIPS: generic: Introduce generic DT-based board support')
Fixes: 3f5f0a4475e1 ('MIPS: generic: Convert SEAD-3 to a generic board')
Signed-off-by: Marcin Nowakowski 
Cc: Paul Burton 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/15464/
Signed-off-by: Ralf Baechle

MIPS: Disable stack checks on MIPS kernels

2017-02-14T09:00:23+00:00

Disable stack checking on MIPS kernels.  Some distribution toolchains
might pass the -fstack-check option to gcc.  This results in a
store-doubleword instruction being emitted at the top of all
functions that checks the available stack space.  E.g.,

  a80000000001d740 :
  a80000000001d740:       ffa0bfc0        sd      zero,-16448(sp)
  a80000000001d744:       2405ffc9        li      a1,-55
  a80000000001d748:       67bdffc0        daddiu  sp,sp,-64

Generally, this is undesirable, and especially on the SGI IP27
platform, it will trigger a NULL pointer dereference in
'_raw_spin_lock_irq' during early init.

Signed-off-by: Joshua Kinard 
Suggested-by: James Hogan 
Cc: Ralf Baechle 
Cc: "Maciej W. Rozycki" 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/15132/
Signed-off-by: James Hogan

MIPS: 'make -s' should be silent

2017-01-25T01:51:09+00:00

A clean mips64 build produces no output except for two lines:

  Checking missing-syscalls for N32
  Checking missing-syscalls for O32

On other architectures, there is no output at all, so let's do the
same here for the sake of build testing. The 'kecho' macro is used
to print the message on a normal build but skip it with 'make -s'.

Fixes: e48ce6b8df5b ("[MIPS] Simplify missing-syscalls for N32 and O32")
Signed-off-by: Arnd Bergmann 
Cc: Paul Burton 
Cc: Matt Redfearn 
Cc: Huacai Chen 
Cc: Maarten ter Huurne 
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/15040/
Signed-off-by: Ralf Baechle

MIPS: Use Makefile.postlink to insert relocations into vmlinux

2017-01-03T15:34:37+00:00

When relocatable support for MIPS was merged, there was no support for
an architecture to add a postlink step for vmlinux. This meant that only
invoking a target within the boot directory, such as uImage, caused the
relocations to be inserted into vmlinux. Building just the vmlinux
target would result in a relocatable kernel with no relocation
information present.

Commit fbe6e37dab97 ("kbuild: add arch specific post-link Makefile")
recified this situation, so MIPS can now define a postlink step to add
relocation information into vmlinux, and remove the additional steps
tacked onto boot targets.

Signed-off-by: Matt Redfearn 
Tested-by: Steven J. Hill 
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14554/
Signed-off-by: Ralf Baechle

MIPS: zboot: Add "uzImage.bin" target

2017-01-03T15:34:31+00:00

uzImage.bin is vmlinuz.bin wrapped in a legacy U-Boot image. Since
the extraction code is inside the image, it does not depend on the
boot loader to extract the kernel.

Signed-off-by: Maarten ter Huurne 
Cc: Alban Bedel 
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14473/
Signed-off-by: Ralf Baechle

MIPS: Fix build of compressed image

2016-11-03T23:37:15+00:00

Changes introduced to arch/mips/Makefile for the generic kernel resulted
in build errors when making a compressed image if platform-y has multiple
values, like this:

make[2]: *** No rule to make target `alchemy/'.
make[1]: *** [vmlinuz] Error 2
make[1]: Target `_all' not remade because of errors.
make: *** [sub-make] Error 2
make: Target `_all' not remade because of errors.

Fix this by quoting $(platform-y) as it is passed to the Makefile in
arch/mips/boot/compressed/Makefile

Reported-by: kernelci.org bot 
Link: https://storage.kernelci.org/next/next-20161017/mips-gpr_defconfig/build.log
Signed-off-by: Matt Redfearn 
Reviewed-by: Paul Burton 
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14405/
Signed-off-by: Ralf Baechle

MIPS: generic: Convert SEAD-3 to a generic board

2016-10-06T16:04:20+00:00

Convert the MIPS SEAD-3 board support to be a generic board, supported
by generic kernels.

Because the SEAD-3 boot protocol was defined long ago and we don't want
to force a switch to the UHI protocol, SEAD-3 is added as a legacy board
which is detected by reading the REVISION register. This may technically
not be a valid memory read & future work will include attempting to
handle that gracefully. In practice since SEAD-3 is the only legacy
board supported by the generic kernel so far the read will only happen
on SEAD-3 boards, and even once Malta is converted the same REVISION
register exists there too. Other boards such as Boston, Ci20 & Ci40 will
use the UHI boot protocol & thus not run any of the legacy board detect
functions.

Signed-off-by: Paul Burton 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14354/
Signed-off-by: Ralf Baechle

MIPS: generic: Introduce generic DT-based board support

2016-10-06T16:04:04+00:00

Introduce a "generic" platform, which aims to be board-agnostic by
making use of device trees passed by the boot protocol defined in the
MIPS UHI (Universal Hosting Interface) specification. Provision is made
for supporting boards which use a legacy boot protocol that can't be
changed, but adding support for such boards or any others is left to
followon patches.

Right now the built kernels expect to be loaded to 0x80100000, ie. in
kseg0. This is fine for the vast majority of MIPS platforms, but
nevertheless it would be good to remove this limitation in the future by
mapping the kernel via the TLB such that it can be loaded anywhere & map
itself appropriately.

Configuration is handled by dynamically generating configs using
scripts/kconfig/merge_config.sh, somewhat similar to the way powerpc
makes use of it. This allows for variations upon the configuration, eg.
differing architecture revisions or subsets of driver support for
differing boards, to be handled without having a large number of
defconfig files.

Signed-off-by: Paul Burton 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14353/
Signed-off-by: Ralf Baechle