Commit Graph
278 Commits
Author SHA1 Message Date
Masahiro Yamada 076f421da5 kbuild: replace cc-name test with CONFIG_CC_IS_CLANG
Evaluating cc-name invokes the compiler every time even when you are
not compiling anything, like 'make help'. This is not efficient.

The compiler type has been already detected in the Kconfig stage.
Use CONFIG_CC_IS_CLANG, instead.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Paul Burton <paul.burton@mips.com> (MIPS)
Acked-by: Joel Stanley <joel@jms.id.au>
2018-11-02 22:49:00 +09:00
Linus Torvalds cc10ad25bb Merge tag 'mips_4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux
Pull MIPS updates from Paul Burton:

 - kexec support for the generic MIPS platform when running on a CPU
   including the MIPS Coherence Manager & related hardware.

 - Improvements to the definition of memory barriers used around MMIO
   accesses, and fixes in their use.

 - Switch to CONFIG_NO_BOOTMEM from Mike Rapoport, finally dropping
   reliance on the old bootmem code.

 - A number of fixes & improvements for Loongson 3 systems.

 - DT & config updates for the Microsemi Ocelot platform.

 - Workaround to enable USB power on the Netgear WNDR3400v3.

 - Various cleanups & fixes.

* tag 'mips_4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (51 commits)
  MIPS: Cleanup DSP ASE detection
  MIPS: dts: Change upper case to lower case
  MIPS: generic: Add Network, SPI and I2C to ocelot_defconfig
  MIPS: Loongson-3: Fix BRIDGE irq delivery problem
  MIPS: Loongson-3: Fix CPU UART irq delivery problem
  MIPS: Remove unused PREF, PREFE & PREFX macros
  MIPS: lib: Use kernel_pref & user_pref in memcpy()
  MIPS: Remove unused CAT macro
  MIPS: Add kernel_pref & user_pref helpers
  MIPS: Remove unused TTABLE macro
  MIPS: Remove unused PIC macros
  MIPS: Remove unused MOVN & MOVZ macros
  MIPS: Provide actually relaxed MMIO accessors
  MIPS: Enforce strong ordering for MMIO accessors
  MIPS: Correct `mmiowb' barrier for `wbflush' platforms
  MIPS: Define MMIO ordering barriers
  MIPS: mscc: add PCB120 to the ocelot fitImage
  MIPS: mscc: add DT for Ocelot PCB120
  MIPS: memset: Limit excessive `noreorder' assembly mode use
  MIPS: memset: Fix CPU_DADDI_WORKAROUNDS `small_fixup' regression
  ...
2018-10-26 14:43:48 -07:00
Paul Burton edbb4233e7 MIPS: Cleanup DSP ASE detection
Currently we hardcode a list of files for which we specify that the
toolchain has DSP ASE support when building for MIPSr2 only. This has a
number of problems:

  1) It doesn't actually ensure that the toolchain supports the DSP ASE
     at all.

  2) It's fragile if we try to use DSP ASE macros in other files.

  3) It makes no provision for MIPSr6 & later systems which also support
     the DSP ASE & end up using the .word directive implementation of
     the DSP macros.

Fix this by detecting assembler support for the DSP ASE globally, not
just for a small set of files, and not just for MIPSr2. This now exposes
use of toolchain DSP support to kernel builds targeting MIPSr1 and
older, so we add .set MIPS_ISA_LEVEL directives prior to all .set dsp
directives in order to prevent the assembler from complaining that the
DSP ASE is only supported with MIPSr2 & higher.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/20901/
Cc: linux-mips@linux-mips.org
2018-10-16 15:30:21 -07:00
Rob Herring 37c8a5fafa 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>
2018-10-02 09:23:21 -05:00
Paul Burton e245767abf MIPS: Use a custom elf-entry program to find kernel entry point
For a long time arch/mips/Makefile used nm to discover the kernel entry
point by looking for the address of the kernel_entry symbol. This
doesn't work for systems which make use of bit 0 of the PC to reflect
the ISA mode - ie. microMIPS (and MIPS16, but we don't support building
kernels that target MIPS16 anyway).

So for a while with commit 5fc9484f5e ("MIPS: Set ISA bit in entry-y
for microMIPS kernels") we manually modified the last nibble of the
output from nm, which worked but wasn't particularly pretty.

Commit 27c524d174 ("MIPS: Use the entry point from the ELF file
header") then cleaned this up by using objdump to print the ELF entry
point which includes the ISA bit, rather than using nm to print the
address of the kernel_entry symbol which doesn't. That removed the ugly
replacement of the last nibble, but added its own ugliness by needing to
manually sign extend in the 32 bit case.

Unfortunately it has been pointed out that objdump's output is
localised, and therefore grepping for its "start address" output doesn't
work when the user's language settings are such that objdump doesn't
print in English.

We could simply revert commit 27c524d174 ("MIPS: Use the entry point
from the ELF file header") and return to the manual replacement of the
last nibble of entry-y, but it seems that was found sufficiently
unpalatable to avoid. We could attempt to force the language used by
objdump by setting an environment variable such as LC_ALL, but that
seems fragile. Instead we add a small tool named elf-entry which simply
prints out the entry point of the kernel in the format we require.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Reported-by: Philippe Reynes <philippe.reynes@softathome.com>
Tested-by: Philippe Reynes <philippe.reynes@softathome.com>
Fixes: 27c524d174 ("MIPS: Use the entry point from the ELF file header")
Patchwork: https://patchwork.linux-mips.org/patch/20322/
Cc: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
2018-08-30 09:39:22 -07:00
Masahiro Yamada d503ac531a kbuild: rename LDFLAGS to KBUILD_LDFLAGS
Commit a0f97e06a4 ("kbuild: enable 'make CFLAGS=...' to add
additional options to CC") renamed CFLAGS to KBUILD_CFLAGS.

Commit 222d394d30 ("kbuild: enable 'make AFLAGS=...' to add
additional options to AS") renamed AFLAGS to KBUILD_AFLAGS.

Commit 06c5040cdb ("kbuild: enable 'make CPPFLAGS=...' to add
additional options to CPP") renamed CPPFLAGS to KBUILD_CPPFLAGS.

For some reason, LDFLAGS was not renamed.

Using a well-known variable like LDFLAGS may result in accidental
override of the variable.

Kbuild generally uses KBUILD_ prefixed variables for the internally
appended options, so here is one more conversion to sanitize the
naming convention.

I did not touch Makefiles under tools/ since the tools build system
is a different world.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
2018-08-24 08:22:08 +09:00
Paul Burton c6d6f4c55f MIPS: Always specify -EB or -EL when using clang
When building using clang, always specify -EB or -EL in order to ensure
we target the desired endianness.

Since clang cross compiles using a single compiler build with multiple
targets, our -dumpmachine tests which don't specify clang's --target
argument check output based upon the build machine rather than the
machine our build will target. This means our detection of whether to
specify -EB fails miserably & we never do. Providing the endianness flag
unconditionally for clang resolves this issue & simplifies the clang
path somewhat.

Signed-off-by: Paul Burton <paul.burton@mips.com>
2018-08-07 16:16:08 -07:00
Paul Burton 344ebf0994 MIPS: Always use -march=<arch>, not -<arch> shortcuts
The VDSO Makefile filters CFLAGS to select a subset which it uses whilst
building the VDSO ELF. One of the flags it allows through is the -march=
flag that selects the architecture/ISA to target.

Unfortunately in cases where CONFIG_CPU_MIPS32_R{1,2}=y and the
toolchain defaults to building for MIPS64, the main MIPS Makefile ends
up using the short-form -<arch> flags in cflags-y. This is because the
calls to cc-option always fail to use the long-form -march=<arch> flag
due to the lack of an -mabi=<abi> flag in KBUILD_CFLAGS at the point
where the cc-option function is executed. The resulting GCC invocation
is something like:

  $ mips64-linux-gcc -Werror -march=mips32r2 -c -x c /dev/null -o tmp
  cc1: error: '-march=mips32r2' is not compatible with the selected ABI

These short-form -<arch> flags are dropped by the VDSO Makefile's
filtering, and so we attempt to build the VDSO without specifying any
architecture. This results in an attempt to build the VDSO using
whatever the compiler's default architecture is, regardless of whether
that is suitable for the kernel configuration.

One encountered build failure resulting from this mismatch is a
rejection of the sync instruction if the kernel is configured for a
MIPS32 or MIPS64 r1 or r2 target but the toolchain defaults to an older
architecture revision such as MIPS1 which did not include the sync
instruction:

    CC      arch/mips/vdso/gettimeofday.o
  /tmp/ccGQKoOj.s: Assembler messages:
  /tmp/ccGQKoOj.s:273: Error: opcode not supported on this processor: mips1 (mips1) `sync'
  /tmp/ccGQKoOj.s:329: Error: opcode not supported on this processor: mips1 (mips1) `sync'
  /tmp/ccGQKoOj.s:520: Error: opcode not supported on this processor: mips1 (mips1) `sync'
  /tmp/ccGQKoOj.s:714: Error: opcode not supported on this processor: mips1 (mips1) `sync'
  /tmp/ccGQKoOj.s:1009: Error: opcode not supported on this processor: mips1 (mips1) `sync'
  /tmp/ccGQKoOj.s:1066: Error: opcode not supported on this processor: mips1 (mips1) `sync'
  /tmp/ccGQKoOj.s:1114: Error: opcode not supported on this processor: mips1 (mips1) `sync'
  /tmp/ccGQKoOj.s:1279: Error: opcode not supported on this processor: mips1 (mips1) `sync'
  /tmp/ccGQKoOj.s:1334: Error: opcode not supported on this processor: mips1 (mips1) `sync'
  /tmp/ccGQKoOj.s:1374: Error: opcode not supported on this processor: mips1 (mips1) `sync'
  /tmp/ccGQKoOj.s:1459: Error: opcode not supported on this processor: mips1 (mips1) `sync'
  /tmp/ccGQKoOj.s:1514: Error: opcode not supported on this processor: mips1 (mips1) `sync'
  /tmp/ccGQKoOj.s:1814: Error: opcode not supported on this processor: mips1 (mips1) `sync'
  /tmp/ccGQKoOj.s:2002: Error: opcode not supported on this processor: mips1 (mips1) `sync'
  /tmp/ccGQKoOj.s:2066: Error: opcode not supported on this processor: mips1 (mips1) `sync'
  make[2]: *** [scripts/Makefile.build:318: arch/mips/vdso/gettimeofday.o] Error 1
  make[1]: *** [scripts/Makefile.build:558: arch/mips/vdso] Error 2
  make[1]: *** Waiting for unfinished jobs....

This can be reproduced for example by attempting to build
pistachio_defconfig using Arnd's GCC 8.1.0 mips64 toolchain from
kernel.org:

  https://mirrors.edge.kernel.org/pub/tools/crosstool/files/bin/x86_64/8.1.0/x86_64-gcc-8.1.0-nolibc-mips64-linux.tar.xz

Resolve this problem by using the long-form -march=<arch> in all cases,
which makes it through the arch/mips/vdso/Makefile's filtering & is thus
consistently used to build both the kernel proper & the VDSO.

The use of cc-option to prefer the long-form & fall back to the
short-form flags makes no sense since the short-form is just an
abbreviation for the also-supported long-form in all GCC versions that
we support building with. This means there is no case in which we have
to use the short-form -<arch> flags, so we can simply remove them.

The manual redefinition of _MIPS_ISA is removed naturally along with the
use of the short-form flags that it accompanied, and whilst here we
remove the separate assembler ISA selection. I suspect that both of
these were only required due to the mips32 vs mips2 mismatch that was
introduced by commit 59b3e8e9aa ("[MIPS] Makefile crapectomy.") and
fixed but not cleaned up by commit 9200c0b2a0 ("[MIPS] Fix Makefile
bugs for MIPS32/MIPS64 R1 and R2.").

I've marked this for backport as far as v4.4 where the MIPS VDSO was
introduced. In earlier kernels there should be no ill effect to using
the short-form flags.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org # v4.4+
Reviewed-by: James Hogan <jhogan@kernel.org>
Patchwork: https://patchwork.linux-mips.org/patch/19579/
2018-06-28 14:24:30 -07:00
Luc Van Oostenryck 1f2f01b122 kbuild: add machine size to CHECKFLAGS
By default, sparse assumes a 64bit machine when compiled on x86-64
and 32bit when compiled on anything else.

This can of course create all sort of problems for the other archs, like
issuing false warnings ('shift too big (32) for type unsigned long'), or
worse, failing to emit legitimate warnings.

Fix this by adding the -m32/-m64 flag, depending on CONFIG_64BIT,
to CHECKFLAGS in the main Makefile (and so for all archs).
Also, remove the now unneeded -m32/-m64 in arch specific Makefiles.

Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-06-01 11:36:58 +09:00
Maciej W. Rozycki 27c524d174 MIPS: Use the entry point from the ELF file header
In order to fetch the correct entry point with the ISA bit included, for
use by non-ELF boot loaders, parse the output of `objdump -f' for the
start address recorded in the kernel executable itself, rather than
using `nm' to get the value of the `kernel_entry' symbol.

Sign-extend the address retrieved if 32-bit, so that execution is
correctly started on 64-bit processors as well.  The tool always prints
the entry point using either 8 or 16 hexadecimal digits, matching the
address width (aka class) of the ELF file, even in the presence of
leading zeros.

Signed-off-by: Maciej W. Rozycki <macro@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/18912/
Signed-off-by: James Hogan <jhogan@kernel.org>
2018-03-22 22:30:58 +00:00
Alexandre Belloni 6bce3deae4 MIPS: generic: Add support for Microsemi Ocelot
Introduce support for the MIPS based Microsemi Ocelot SoCs.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Allan Nielsen <Allan.Nielsen@microsemi.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/18858/
[jhogan@kernel.org: update ocelot_defconfig specification]
Signed-off-by: James Hogan <jhogan@kernel.org>
2018-03-21 23:33:10 +00:00
James Hogan cccd0b9a72 MIPS: Expand help text to list generic defconfigs
Expand the MIPS Makefile help text to list generic board names, generic
defconfigs, and legacy defconfigs which have been converted to generic
and are still usable.

Here's a snippet of the new "make ARCH=mips help" output:
  ...
  If you are targeting a system supported by generic kernels you may
  configure the kernel for a given architecture target like so:

  {micro32,32,64}{r1,r2,r6}{el,}_defconfig <BOARDS="list of boards">

  Where BOARDS is some subset of the following:
    boston
    ni169445
    ranchu
    sead-3
    xilfpga

  Specifically the following generic default configurations are
  supported:

  32r1_defconfig           - Build generic kernel for MIPS32 r1
  32r1el_defconfig         - Build generic kernel for MIPS32 r1 little endian
  32r2_defconfig           - Build generic kernel for MIPS32 r2
  32r2el_defconfig         - Build generic kernel for MIPS32 r2 little endian
  32r6_defconfig           - Build generic kernel for MIPS32 r6
  32r6el_defconfig         - Build generic kernel for MIPS32 r6 little endian
  64r1_defconfig           - Build generic kernel for MIPS64 r1
  64r1el_defconfig         - Build generic kernel for MIPS64 r1 little endian
  64r2_defconfig           - Build generic kernel for MIPS64 r2
  64r2el_defconfig         - Build generic kernel for MIPS64 r2 little endian
  64r6_defconfig           - Build generic kernel for MIPS64 r6
  64r6el_defconfig         - Build generic kernel for MIPS64 r6 little endian
  micro32r2_defconfig      - Build generic kernel for microMIPS32 r2
  micro32r2el_defconfig    - Build generic kernel for microMIPS32 r2 little endian

  The following legacy default configurations have been converted to
  generic and can still be used:

  sead3_defconfig          - Build 32r2el_defconfig BOARDS=sead-3
  sead3micro_defconfig     - Build micro32r2el_defconfig BOARDS=sead-3
  xilfpga_defconfig        - Build 32r2el_defconfig BOARDS=xilfpga
  ...

Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Matt Redfearn <matt.redfearn@mips.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kbuild@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/18598/
2018-03-05 15:11:42 +00:00
James Hogan 318df80628 MIPS: Refactor legacy defconfigs
Define legacy defconfigs which have been converted to the generic
platform more programatically, so that they can be listed in the
Makefile help text and as a separate Makefile target without
duplication.

Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Matt Redfearn <matt.redfearn@mips.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kbuild@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/18596/
2018-02-19 21:03:07 +00:00
Marcin Nowakowski 4a5dc51e93 MIPS: crypto: Add crc32 and crc32c hw accelerated module
This module registers crc32 and crc32c algorithms that use the
optional CRC32[bhwd] and CRC32C[bhwd] instructions in MIPSr6 cores.

Signed-off-by: Marcin Nowakowski <marcin.nowakowski@mips.com>
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: linux-mips@linux-mips.org
Cc: linux-crypto@vger.kernel.org
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Patchwork: https://patchwork.linux-mips.org/patch/18601/
[jhogan@kernel.org: Add CRYPTO_ALG_OPTIONAL_KEY flag on Eric Biggers'
 suggestion, due to commit a208fa8f33 ("crypto: hash - annotate
 algorithms taking optional key") in v4.16-rc1]
2018-02-19 20:50:36 +00:00
James Hogan 8e4789d288 MIPS: XPA: Use XPA instructions in assembly
Utilise XPA instructions MFHC0 & MTHC0 in inline assembly instead of
directly encoding them with the _ASM_INSN* macros, and transparently
implement these instructions as assembler macros if the toolchain
doesn't support them natively, using the recently introduced assembler
macro helpers.

The old direct encodings were restricted to using the register $at, so
this allows the extra register moves to go away (saving a grand total of
24 bytes).

Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17775/
2018-01-22 20:51:55 +00:00
Daniel Sabogal 809769a8f0 MIPS: Fix vmlinuz build when ZBOOT is selected
vmlinuz is not built by default for platforms using
COMPRESSION_FNAME (e.g. Malta) due to an erroneous
check on ZBOOT

Signed-off-by: Daniel Sabogal <dsabogalcc@gmail.com>
Reviewed-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/18466/
Signed-off-by: James Hogan <jhogan@kernel.org>
2018-01-18 21:52:04 +00:00
Zubair Lutfullah Kakakhel 0861aa1251 MIPS: Xilfpga: Switch to using generic defconfigs
Use the generic platform code and remove arch/mips/xilfpga

Signed-off-by: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/15847/
[jhogan@kernel.org: Update arch/mips/Makefile snippet and move to end]
Signed-off-by: James Hogan <jhogan@kernel.org>
2017-11-08 22:54:14 +00:00
Matt Redfearn 04d8405e71 MIPS: Set defconfig target to a generic system for 32r2el
The default system type should be a MIPS generic kernel. In order to
include some level of board support, select a 32r2el generic defconfig
by default. The alternative would be to use "generic_defconfig" but
rather unintuitvely that is a bare bones configuration with no platform
support so is not usable in practice.

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14715/
Signed-off-by: James Hogan <jhogan@kernel.org>
2017-11-08 22:25:55 +00:00
Corey Minyard 866b6a89c6 MIPS: Add DWARF unwinding to assembly
This will allow kdump dumps to work correclty with MIPS and
future DWARF unwinding of the stack to give accurate tracebacks.

Signed-off-by: Corey Minyard <cminyard@mvista.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16990/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-09-06 11:01:52 +02:00
Paul Burton a4c2f79787 MIPS: Prevent direct use of generic_defconfig
Using generic_defconfig directly is unlikely to be what a user actually
wants to do - it doesn't specify any particular ISA revision & it
doesn't enable any board or driver support, resulting in a largely
useless kernel.

Prevent users from using it directly, printing a helpful message to
point them in the right direction if they attempt to.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16946/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-30 00:57:28 +02:00
Paul Burton 27e0d4b051 MIPS: generic: Allow filtering enabled boards by requirements
Up until now when configuring a generic kernel all board config
fragments have been merged by default unless boards are explicitly
selected by the user specifying BOARDS=.

In many cases this is sub-optimal, since some boards don't make sense to
include in some kernels. For example the MIPS SEAD-3 development board
has only ever been used with 32 bit CPUs, so including support for the
SEAD-3 in a 64 bit kernel is wasteful.

This patch introduces support for specifying requirements in board
config fragments, using comments formatted like so:

  # require CONFIG_BLA=y

For example the SEAD-3 board could specify that it should only be merged
for 32 bit kernels using a requirement line like the following:

  # require CONFIG_32BIT=y

A new generic-board-config.sh script is introduced to handle selecting
the board config fragments to merge & calling merge_config.sh to merge
them. In order to allow requirements to check Kconfig symbols that are
implicitly selected, rather than explicitly specified by
generic_defconfig or one of the ISA config fragments, an intermediate
.config file is saved & used as a reference when checking requirements.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16943/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-30 00:57:28 +02:00
Paul Burton 436c6a4452 MIPS: Allow platform to specify multiple its.S files
In preparation for splitting arch/mips/generic/vmlinux.its.S into
multiple files such that it doesn't become a conflict magnet as boards
are added, allow platforms to specify a list of image tree source files
which will be concatenated to form the final source used to build the
image tree.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16938/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29 15:21:52 +02:00
Paul Burton 3b2db173f0 MIPS: Remove unused R6000 support
The kernel contains a small amount of incomplete code aimed at
supporting old R6000 CPUs. This is:

  - Unused, as no machine selects CONFIG_SYS_HAS_CPU_R6000.

  - Broken, since there are glaring errors such as r6000_fpu.S moving
    the FCSR register to t1, then ignoring it & instead saving t0 into
    struct sigcontext...

  - A maintenance headache, since it's code that nobody can test which
    nevertheless imposes constraints on code which it shares with other
    machines.

Remove this incomplete & broken R6000 CPU support in order to clean up
and in preparation for changes which will no longer need to consider
dragging the pretense of R6000 support along with them.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16236/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-29 15:21:51 +02:00
Paul Burton 5fc9484f5e MIPS: Set ISA bit in entry-y for microMIPS kernels
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 <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16950/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-08-08 14:00:50 +02:00
Miodrag Dinic 21855a6e5b MIPS: build: Fix "-modd-spreg" switch usage when compiling for mips32r6
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 <miodrag.dinic@imgtec.com>
Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com>
Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com>
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 <ralf@linux-mips.org>
2017-06-29 02:42:23 +02:00