The ARM architected timer driver doesn't compile without
GENERIC_CLOCKEVENTS selected, so ensure that we select it when building
for a platform that has the timer.

Without this patch, mach-virt fails to build without something like
mach-vexpress also selected.
Acked-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Make sure that seccomp filter won't be built when ARM OABI is in use,
since there is work needed to distinguish calling conventions. Until
that is done (which is likely never since OABI is deprecated), make
sure seccomp filter is unavailable in the OABI world.
Signed-off-by: NKees Cook <keescook@chromium.org>
Reviewed-by: NWill Drewry <wad@chromium.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Given recent discussions about the lack of OABI in the wild, switch
CONFIG_OABI_COMPAT to off-by-default to encourage more system builders
to avoid it.
Signed-off-by: NKees Cook <keescook@chromium.org>
Acked-by: NNicolas Pitre <nico@linaro.org>
Acked-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This removes the XSCALE_PMU Kconfig param, which is defined
but no longer used in makefiles and source files.
Signed-off-by: NMichael Opdenacker <michael.opdenacker@free-electrons.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Our spinlocks are only 32-bit (2x16-bit tickets) and, on processors
with 64-bit atomic instructions, cmpxchg64 makes use of the double-word
exclusive accessors.

This patch wires up the cmpxchg-based lockless lockref implementation
for ARM.
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The SA1100 was implementing its own variants of gpio_get_value()
and gpio_set_value() and only selectively falling back to
gpiolib for extended (EGPIO) handling. However the driver in
gpio/gpio-sa1100.c already handles the same functionality for
these lines, yet remain unused.

The only upside would be things like a timing-critical hotpath
on bit-banged GPIO, but that kind of things does not seem to
happen on these GPIOs, so it is not worth having the extra
complexity.

Tested with some buttons on the Compaq iPAQ H3630.

Cc: Kristoffer Ericson <kristoffer.ericson@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This converts the gemini machine to use generic clockevents
by rewriting the timer driver.

Cc: arm@kernel.org
Cc: Hans Ulli Kroll <ulli.kroll@googlemail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NOlof Johansson <olof@lixom.net>

The Kconfig for arch/arm/mach-ixp4xx has a local definition
of ARCH_SUPPORTS_BIG_ENDIAN which could be used elsewhere.
This means that if IXP4xx is selected and this symbol is
selected eleswhere then an warning is produced.

Clean the following error up by making the symbol be
selected by the main ARCH_IXP4XX definition and have a
common definition in arch/arm/mm/Kconfig

warning: (ARCH_xxx) selects ARCH_SUPPORTS_BIG_ENDIAN which has unmet direct dependencies (ARCH_IXP4XX)
warning: (ARCH_xxx) selects ARCH_SUPPORTS_BIG_ENDIAN which has unmet direct dependencies (ARCH_IXP4XX)
Signed-off-by: NBen Dooks <ben.dooks@codethink.co.uk>

The Device Tree boot path now supports everything the ATAG
boot can provide, and the two are equivalent. This deletes
the ATAG boot path from the Integrator/AP and
Integrator/CP platforms to move them on to the future.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

CLKDEV_LOOKUP selects HAVE_CLK and COMMON_CLK selects CLKDEV_LOOKUP. So
all symbols that select at least two of these symbols can be simplified.

For imx, omap2 and ux500 some rearrangements were necessary before the
simplification.
Acked-by: NTony Lindgren <tony@atomide.com>
Acked-by: NStephen Boyd <sboyd@codeaurora.org>
Acked-by: NDinh Nguyen <dinguyen@altera.com>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: NPawel Moll <pawel.moll@arm.com>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NOlof Johansson <olof@lixom.net>

CONFIG_PLAT_S3C64XX has been kept in place way too long since it was
marked as temporary in commit

110d85ac ARM: S3C64XX: Eliminate plat-s3c64xx

After fixing all users of it in previous patches, this patch finally
kills this temporary Kconfig entry.
Signed-off-by: NTomasz Figa <tomasz.figa@gmail.com>
Signed-off-by: NKukjin Kim <kgene.kim@samsung.com>

All other platforms have this condition checked inside their own Kconfig
files, so for consistency this patch makes it this way for mach-s3c64xx
as well.
Signed-off-by: NTomasz Figa <tomasz.figa@gmail.com>
Signed-off-by: NKukjin Kim <kgene.kim@samsung.com>

The Gemini has no need of a <mach/gpio.h> header as this is only
used by the machine-local gpio.c gpiochip driver, which is also
only using the irq_to_gpio() macro. Delete the file, move the single
macro into the driver and remove the NEED_MACH_GPIO_H flag.

Cc: Hans Ulli Kroll <ulli.kroll@googlemail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This patch implements the functions required for the perf registers API,
allowing the perf tool to interface kernel register dumps with libunwind
in order to provide userspace backtracing.

Cc: Jean Pihet <jean.pihet@linaro.org>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

With the 64-bit requirement removed from VIRT_CPU_ACCOUNTING_GEN,
allow ARM platforms to enable it.  Since VIRT_CPU_ACCOUNTING_GEN is a
dependency for full NO_HZ, this allows ARM platforms to enable full
NO_HZ as well.
Signed-off-by: NKevin Hilman <khilman@linaro.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Arm Linux <linux-arm-kernel@lists.infradead.org>
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>

The PXA sub-architecture appears to have a custom <mach/gpio.h>
for no reason whatsoever. The file became completely empty
after Haojian removed the remaining content in
commit 157d2644
"ARM: pxa: change gpio to platform device".

That commit added these two lines:

However it seems like deleting the file has no effect
whatsoever on the kernel compilation.

Cc: Eric Miao <eric.y.miao@gmail.com>
Cc: Russell King <linux@arm.linux.org.uk>
Acked-by: NHaojian Zhuang <haojian.zhuang@marvell.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The MMP sub-architecture appears to have a custom <mach/gpio.h>
for no reason whatsoever. The file became completely empty
after Haojian removed the remaining content in
commit 157d2644
"ARM: pxa: change gpio to platform device".

Cc: Eric Miao <eric.y.miao@gmail.com>
Acked-by: NHaojian Zhuang <haojian.zhuang@marvell.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Remove NEED_MACH_GPIO_H config select option for ARCH_DAVINCI
to start using gpiolib interface for davinci platforms. This makes
it easier to use the gpio driver on other platforms as it breaks
dependency on mach-davinci.

Latencies for gpio_get/set APIs will increase. On measurement,
latency was found to have increased by 18 microsecond with
gpiolib API as compared to inline APIs.

Measurement was done on DA850 EVM for gpio_get_value() API by
taking the printk timing across the call with interrupts disabled.

  inline gpio API with interrupt disabled
  [   29.734337] before gpio_get
  [   29.736847] after gpio_get

  Time difference 0.00251

  gpio library with interrupt disabled
  [  272.876763] before gpio_get
  [  272.879291] after gpio_get

  Time difference 0.002528
  Latency increased by (0.002528 -  0.00251) = 18 microsecond.

While at it, remove GPIO_TYPE_DAVINCI enum definition as
gpio-davinci.c is converted to Linux device driver model.
Signed-off-by: NPhilip Avinash <avinashphilip@ti.com>
Signed-off-by: NLad, Prabhakar <prabhakar.csengg@gmail.com>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
[nsekhar@ti.com: minor edits to commit message]
Signed-off-by: NSekhar Nori <nsekhar@ti.com>

This prevents the linker erroring with:

arm-linux-ld: error: arch/arm/lib/xor-neon.o uses VFP instructions, whereas arch/arm/lib/built-in.o does not
arm-linux-ld: failed to merge target specific data of file arch/arm/lib/xor-neon.o

This is due to the non-neon files being marked as containing FPA data/
instructions (even though they do not) being mixed with files which
contain VFP, which is an incompatible floating point format.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This converts the IOP32x and IOP33x platforms to pass their
base address offset by a resource attached to a platform device
instead of using static offset macros implicitly passed
through <linux/gpio.h> including <mach/gpio.h>. Delete the
local <mach/gpio.h> and <asm/hardware/iop3xx-gpio.h> headers
and remove the selection of NEED_MACH_GPIO_H.

Pass the virtual address as a resource in the platform device
at this point for bisectability, next patch will pass the
physical address as is custom.

Cc: Lennert Buytenhek <kernel@wantstofly.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Mikael Pettersson <mikpe@it.uu.se>
Tested-by: NAaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Move the IOP GPIO driver to live with its siblings in the
GPIO subsystem.

Cc: Lennert Buytenhek <kernel@wantstofly.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Mikael Pettersson <mikpe@it.uu.se>
Tested-by: NAaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The Shark machine sub-architecture (also known as DNARD, the
DIGITAL Network Appliance Reference Design) lacks a maintainer
able to apply and test patches to modernize the architecture.

It is suspected that the current kernel, while it compiles,
does not even boot on this machine. The listed maintainer has
expressed that he will not be able to spend any time on the
maintenance for the coming year.

So let's delete it from the kernel for now. It can always be
resurrected with git revert if maintenance is resumed.

As the VIA82c505 PCI adapter was only used by this
architecture, that gets deleted too.

Cc: arm@kernel.org
Cc: Alexander Schulz <alex@shark-linux.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This patch migrates the s3c64xx platform to use the new clock driver
using Common Clock Framework.
Signed-off-by: NTomasz Figa <tomasz.figa@gmail.com>
Signed-off-by: NKukjin Kim <kgene.kim@samsung.com>

After the last architecture switched to generic hard irqs the config
options HAVE_GENERIC_HARDIRQS & GENERIC_HARDIRQS and the related code
for !CONFIG_GENERIC_HARDIRQS can be removed.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Keep arch/arm/Kconfig select statements sorted alphabetically.  I've
added a comment at the bottom of the main bank for CONFIG_ARM to this
effect so hopefully this will keep things more in order.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Olof Johansson reports that the tests against HZ_FIXED seem
non-functional.  Fix this by using '0' as a sentinel for "not
specified" and test against that instead.
Reported-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

On Cortex-A15 CPUs up to and including r0p4, in certain rare sequences
of code, the loop buffer may deliver incorrect instructions. This
workaround disables the loop buffer to avoid the erratum.
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Support IRQCHIP & CONFIG_MULTI_IRQ_HANDLER in irq-mmp driver.
Signed-off-by: NHaojian Zhuang <haojian.zhuang@gmail.com>
Reviewed-by: NDaniel Drake <dsd@laptop.org>

commit 40b31360 ("Finally eradicate
CONFIG_HOTPLUG") removed remaining references to CONFIG_HOTPLUG, but missed
a few plain English references in the CONFIG_KEXEC help texts.

Remove them, too.
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Acked-by: NStephen Rothwell <sfr@canb.auug.org.au>
Acked-by: NIngo Molnar <mingo@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add support for suspend/resume operations. The implemented procedures
are identical to the ones for ARM926.
Signed-off-by: NEzequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

All timer interrupts and the perf interrupt are marked NO_THREAD, so
its safe to allow forced interrupt threading.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

DRA7xx has 8 GPIO banks so that there are 32x8 = 256 GPIOs.
In order for the gpiolib to detect and initialize these
and other TWL GPIOs, ARCH_NR_GPIO is set to 512 using the
kconfig default for DRA7.
Signed-off-by: NR Sricharan <r.sricharan@ti.com>
Signed-off-by: NRajendra Nayak <rnayak@ti.com>

Now that we have weak versions for each of the PCI MSI architecture
functions, we can actually build the MSI support for all platforms,
regardless of whether they provide or not architecture-specific
versions of those functions. For this reason, the ARCH_SUPPORTS_MSI
hidden kconfig boolean becomes useless, and this patch gets rid of it.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Tested-by: NDaniel Price <daniel.price@gmail.com>
Tested-by: NThierry Reding <thierry.reding@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: linux-s390@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: x86@kernel.org
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: linux-ia64@vger.kernel.org
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: David S. Miller <davem@davemloft.net>
Cc: sparclinux@vger.kernel.org
Cc: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: NJason Cooper <jason@lakedaemon.net>

This allows us to remove the init_time callback in the DT machine
descriptors, shrinking the code.
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NDavid Brown <davidb@codeaurora.org>

As the need for an IRQ chip handling PWM timer interrupt chaining is
gone now, this patch removes all the code made unnecessary.
Signed-off-by: NTomasz Figa <t.figa@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Tested-by: NHeiko Stuebner <heiko@sntech.de>
Tested-by: NMark Brown <broonie@linaro.org>
Tested-by: NSylwester Nawrocki <sylvester.nawrocki@gmail.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>

This patch moves all Samsung platforms using PWM clocksource from legacy
samsung-time to new samsung-pwm-timer driver.
Signed-off-by: NTomasz Figa <tomasz.figa@gmail.com>
Reviewed-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Tested-by: NHeiko Stuebner <heiko@sntech.de>
Tested-by: NMark Brown <broonie@linaro.org>
Tested-by: NSylwester Nawrocki <sylvester.nawrocki@gmail.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>

Only the basic call to aid debugging.

*** NOT FOR PRODUCTION ***

Usage:

	echo <cpuid>,<clusterid> > /dev/b.L_switcher

where <cpuid> is the logical CPU number, and <clusterid> is 0 for the
first cluster and 1 for the second cluster.
Signed-off-by: Nnicolas Pitre <nico@linaro.org>

Move the machine vector stubs into the page above the vector page,
which we can prevent from being visible to userspace.  Also move
the reset stub, and place the swi vector at a location that the
'ldr' can get to it.

This hides pointers into the kernel which could give valuable
information to attackers, and reduces the number of exploitable
instructions at a fixed address.

Cc: <stable@vger.kernel.org>
Acked-by: NNicolas Pitre <nico@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

General forms of huge_pte_alloc, huge_pte_offset and follow_huge_pmd
are now available in mm/hugetlb.c.

This patch removes the ARM copies of these functions and activates
the general ones by enabling:
CONFIG_ARCH_WANT_GENERAL_HUGETLB
Signed-off-by: NSteve Capper <steve.capper@linaro.org>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This is the core code implementing big.LITTLE switcher functionality.
Rationale for this code is available here:

http://lwn.net/Articles/481055/

The main entry point for a switch request is:

void bL_switch_request(unsigned int cpu, unsigned int new_cluster_id)

If the calling CPU is not the wanted one, this wrapper takes care of
sending the request to the appropriate CPU with schedule_work_on().

At the moment the core switch operation is handled by bL_switch_to()
which must be called on the CPU for which a switch is requested.

What this code does:

  * Return early if the current cluster is the wanted one.

  * Close the gate in the kernel entry vector for both the inbound
    and outbound CPUs.

  * Wake up the inbound CPU so it can perform its reset sequence in
    parallel up to the kernel entry vector gate.

  * Migrate all interrupts in the GIC targeting the outbound CPU
    interface to the inbound CPU interface, including SGIs. This is
    performed by gic_migrate_target() in drivers/irqchip/irq-gic.c.

  * Call cpu_pm_enter() which takes care of flushing the VFP state to
    RAM and save the CPU interface config from the GIC to RAM.

  * Modify the cpu_logical_map to refer to the inbound physical CPU.

  * Call cpu_suspend() which saves the CPU state (general purpose
    registers, page table address) onto the stack and store the
    resulting stack pointer in an array indexed by the updated
    cpu_logical_map, then call the provided shutdown function.
    This happens in arch/arm/kernel/sleep.S.

At this point, the provided shutdown function executed by the outbound
CPU ungates the inbound CPU. Therefore the inbound CPU:

  * Picks up the saved stack pointer in the array indexed by its MPIDR
    in arch/arm/kernel/sleep.S.

  * The MMU and caches are re-enabled using the saved state on the
    provided stack, just like if this was a resume operation from a
    suspended state.

  * Then cpu_suspend() returns, although this is on the inbound CPU
    rather than the outbound CPU which called it initially.

  * The function cpu_pm_exit() is called which effect is to restore the
    CPU interface state in the GIC using the state previously saved by
    the outbound CPU.

  * Exit of bL_switch_to() to resume normal kernel execution on the
    new CPU.

However, the outbound CPU is potentially still running in parallel while
the inbound CPU is resuming normal kernel execution, hence we need
per CPU stack isolation to execute bL_do_switch().  After the outbound
CPU has ungated the inbound CPU, it calls mcpm_cpu_power_down() to:

  * Clean its L1 cache.

  * If it is the last CPU still alive in its cluster (last man standing),
    it also cleans its L2 cache and disables cache snooping from the other
    cluster.

  * Power down the CPU (or whole cluster).

Code called from bL_do_switch() might end up referencing 'current' for
some reasons.  However, 'current' is derived from the stack pointer.
With any arbitrary stack, the returned value for 'current' and any
dereferenced values through it are just random garbage which may lead to
segmentation faults.

The active page table during the execution of bL_do_switch() is also a
problem.  There is no guarantee that the inbound CPU won't destroy the
corresponding task which would free the attached page table while the
outbound CPU is still running and relying on it.

To solve both issues, we borrow some of the task space belonging to
the init/idle task which, by its nature, is lightly used and therefore
is unlikely to clash with our usage.  The init task is also never going
away.

Right now the logical CPU number is assumed to be equivalent to the
physical CPU number within each cluster. The kernel should also be
booted with only one cluster active.  These limitations will be lifted
eventually.
Signed-off-by: NNicolas Pitre <nico@linaro.org>