linux.git/arch/mips/Makefile, branch v4.16.13

MIPS: XPA: Use XPA instructions in assembly

2018-01-22T20:51:55+00:00

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 
Cc: Ralf Baechle 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17775/

MIPS: Fix vmlinuz build when ZBOOT is selected

2018-01-18T21:52:04+00:00

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 
Reviewed-by: James Hogan 
Cc: Ralf Baechle 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/18466/
Signed-off-by: James Hogan

MIPS: Xilfpga: Switch to using generic defconfigs

2017-11-08T22:54:14+00:00

Use the generic platform code and remove arch/mips/xilfpga

Signed-off-by: Zubair Lutfullah Kakakhel 
Cc: Ralf Baechle 
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

MIPS: Set defconfig target to a generic system for 32r2el

2017-11-08T22:25:55+00:00

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 
Cc: Ralf Baechle 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14715/
Signed-off-by: James Hogan

MIPS: Add DWARF unwinding to assembly

2017-09-06T09:01:52+00:00

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 
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

MIPS: Prevent direct use of generic_defconfig

2017-08-29T22:57:28+00:00

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 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16946/
Signed-off-by: Ralf Baechle

MIPS: generic: Allow filtering enabled boards by requirements

2017-08-29T22:57:28+00:00

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 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16943/
Signed-off-by: Ralf Baechle

MIPS: Allow platform to specify multiple its.S files

2017-08-29T13:21:52+00:00

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 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16938/
Signed-off-by: Ralf Baechle

MIPS: Remove unused R6000 support

2017-08-29T13:21:51+00:00

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 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16236/
Signed-off-by: Ralf Baechle

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