The [user space] interface does not filter out offline cpus. It merily
guarantees that the mask contains at least one online cpu.

So the selector in the irq chip implementation needs to make sure to
pick only an online cpu because otherwise:

     Offline Core 1
     Set affinity to 0xe (is valid due to online mask 0xd)
     cpumask_first will pick core 1, which is offline
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: ia64 <linux-ia64@vger.kernel.org>
Link: http://lkml.kernel.org/r/20140304203100.650414633@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

LTO patches add __visible to the asmlinkage define, causing
compilation warnings like:

  drivers/irqchip/irq-gic.c:283:1: warning: 'externally_visible'
  attribute have effect only on public objects [-Wattributes]

Drop asmlinkage here to avoid such warnings.
Reported-by: NOlof's autobuilder <build@lixom.net>
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: khilman@linaro.org
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Josh Cartwright <joshc@codeaurora.org>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1393980030-17770-1-git-send-email-sboyd@codeaurora.orgSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Reported-by: NIngo Molnar <mingo@kernel.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

drivers/irqchip/irq-gic.c:53:23: warning: duplicate [noderef]
drivers/irqchip/irq-gic.c:651:6: warning: symbol 'gic_raise_softirq' was not declared. Should it be static?
drivers/irqchip/irq-gic.c:872:29: warning: symbol 'gic_irq_domain_ops' was not declared. Should it be static?
drivers/irqchip/irq-gic.c:977:12: warning: symbol 'gic_of_init' was not declared. Should it be static?
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1393981321-25721-1-git-send-email-sboyd@codeaurora.orgSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

drivers/irqchip/irqchip.c:27:13: warning: symbol 'irqchip_init'
was not declared. Should it be static?
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Cc: trivial@kernel.org
Link: http://lkml.kernel.org/r/1393981281-25553-1-git-send-email-sboyd@codeaurora.orgSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Compiling last minute changes without setting the proper config
options is not really clever.
Reported-by: NFengguang Wu <fengguang.wu@intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

commit: 8f945a33 (genirq: Move kstat_incr_irqs_this_cpu() to core)
unearthed the following:

arch/m68k/kernel/ints.c:34:15: error: variable 'auto_irq_chip' has initializer but incomplete type
arch/m68k/kernel/ints.c:35:2: error: unknown field 'name' specified in initializer
arch/m68k/kernel/ints.c:35:2: warning: excess elements in struct initializer [enabled by default]

The reason is that this file requires linux/irq.h and magically
pulled that in via linux/kernel_stat.h

The commit above got rid of the pointless include of linux/irq.h in
linux/kernel_stat.h and therefor broke the build.

Include linux/irq.h

Reported-by: fengguang.wu@intel.com
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Commit b8a9a11b (powerpc: eeh: Kill another abuse of irq_desc) is
missing some brackets .....

It's not a good idea to write patches in grumpy mode and then forget
to at least compile test them or rely on the few eyeballs discussing
that patch to spot it.....

Reported-by: fengguang.wu@intel.com
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Gavin Shan <shangw@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: ppc <linuxppc-dev@lists.ozlabs.org>

commit: 8f945a33 (genirq: Move kstat_incr_irqs_this_cpu() to core)
unearthed the following:

   arch/s390/kernel/irq.c: In function 'init_IRQ':
>> arch/s390/kernel/irq.c:93:2: error: implicit declaration of function 'irq_reserve_irqs'
[-Werror=implicit-function-declaration]
....
   cc1: some warnings being treated as errors
--
   drivers/s390/cio/cio.c: In function 'init_cio_interrupts':
>> drivers/s390/cio/cio.c:594:2: error: implicit declaration of function
'irq_set_chip_and_handler' [-Werror=implicit-function-declaration]
[-Werror=implicit-function-declaration]
....
   cc1: some warnings being treated as errors

The reason is that those files require linux/irq.h and magically
pulled that in via linux/kernel_stat.h

The commit above got rid of the pointless include of linux/irq.h in
linux/kernel_stat.h and therefor broke the build.

Include linux/irq.h

Reported-by: fengguang.wu@intel.com
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: s390 <linux-s390@vger.kernel.org>

Reported-by: fengguang.wu@intel.com
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linuxdrivers <devel@linuxdriverproject.org>
Cc: x86 <x86@kernel.org>

Commit 1aec1696 (x86: Hyperv: Cleanup the irq mess) removed the
ability to build the hyperv stuff as a module. Bring it back.

Reported-by: fengguang.wu@intel.com
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linuxdrivers <devel@linuxdriverproject.org>
Cc: x86 <x86@kernel.org>

This patch removes the IRQF_DISABLED flag from x86 architecture
code. It's a NOOP since 2.6.35 and it will be removed one day.
Signed-off-by: NMichael Opdenacker <michael.opdenacker@free-electrons.com>
Cc: venki@google.com
Link: http://lkml.kernel.org/r/1393965305-17248-1-git-send-email-michael.opdenacker@free-electrons.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

This patch removes the IRQF_DISABLED flag from mn10300 architecture
code. It's a NOOP since 2.6.35 and it will be removed one day.
Signed-off-by: NMichael Opdenacker <michael.opdenacker@free-electrons.com>
Cc: srivatsa.bhat@linux.vnet.ibm.com
Cc: linux-am33-list@redhat.com
Cc: dhowells@redhat.com
Cc: yasutake.koichi@jp.panasonic.com
Link: http://lkml.kernel.org/r/1393965111-17092-1-git-send-email-michael.opdenacker@free-electrons.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

This patch removes the IRQF_DISABLED flag from ia64 architecture
code. It's a NOOP since 2.6.35 and it will be removed one day.
Signed-off-by: NMichael Opdenacker <michael.opdenacker@free-electrons.com>
Cc: paul.gortmaker@windriver.com
Cc: viro@zeniv.linux.org.uk
Cc: srivatsa.bhat@linux.vnet.ibm.com
Cc: andriy.shevchenko@linux.intel.com
Cc: fenghua.yu@intel.com
Cc: tony.luck@intel.com
Link: http://lkml.kernel.org/r/1393964953-17002-1-git-send-email-michael.opdenacker@free-electrons.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

There is no point in having an incomplete copy of irq_set_affinity()
for the hotplug irq migration code.

Use the core function instead and while at it switch to
for_each_active_irq()
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: xtensa <linux-xtensa@linux-xtensa.org>
Link: http://lkml.kernel.org/r/20140223212736.664624945@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

The user space interface does not filter out offline cpus. It merily
verifies that the mask contains at least one online cpu. So the
selector in the irq chip implementation needs to make sure to pick
only an online cpu because otherwise:

     Offline Core 1
     Set affinity to 0xe
     Selector will pick first set bit, i.e. core 1
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Chris Zankel <chris@zankel.net>
Cc: xtensa <linux-xtensa@linux-xtensa.org>

There is no point in having an incomplete copy of irq_set_affinity()
for the hotplug irq migration code.

Use the core function instead.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: sh <linux-sh@vger.kernel.org>
Link: http://lkml.kernel.org/r/20140223212736.774961401@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

No more users outside the core code. Put it into the poison
cabinet. That also gets rid of the linux/irq.h include in
kernel_stat.h
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140223212739.124207133@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

The vmbus/hyperv interrupt handling is another complete trainwreck and
probably the worst of all currently in tree.

If CONFIG_HYPERV=y then the interrupt delivery to the vmbus happens
via the direct HYPERVISOR_CALLBACK_VECTOR. So far so good, but:

  The driver requests first a normal device interrupt. The only reason
  to do so is to increment the interrupt stats of that device
  interrupt. For no reason it also installs a private flow handler.

  We have proper accounting mechanisms for direct vectors, but of
  course it's too much effort to add that 5 lines of code.

  Aside of that the alloc_intr_gate() is not protected against
  reallocation which makes module reload impossible.

Solution to the problem is simple to rip out the whole mess and
implement it correctly.

First of all move all that code to arch/x86/kernel/cpu/mshyperv.c and
merily install the HYPERVISOR_CALLBACK_VECTOR with proper reallocation
protection and use the proper direct vector accounting mechanism.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NK. Y. Srinivasan <kys@microsoft.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linuxdrivers <devel@linuxdriverproject.org>
Cc: x86 <x86@kernel.org>
Link: http://lkml.kernel.org/r/20140223212739.028307673@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NDavid Vrabel <david.vrabel@citrix.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Xen <xen-devel@lists.xenproject.org>
Link: http://lkml.kernel.org/r/20140223212738.808648133@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

HyperV abuses a device interrupt to account for the
HYPERVISOR_CALLBACK_VECTOR.

Provide proper accounting as we have for the other vectors as well.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: x86 <x86@kernel.org>
Link: http://lkml.kernel.org/r/20140223212738.681855582@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Let the core do the irq_desc resolution.

No functional change.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: ia64 <linux-ia64@vger.kernel.org>
Link: http://lkml.kernel.org/r/20140223212738.099977064@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Let the core do the irq_desc resolution.

No functional change.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: s390 <linux-s390@vger.kernel.org>
Link: http://lkml.kernel.org/r/20140223212737.983433636@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Let the core do the irq_desc resolution.

No functional change.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: David Howells <dhowells@redhat.com>
Cc: mn10300 <linux-am33-list@redhat.com>
Link: http://lkml.kernel.org/r/20140223212737.751487689@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Let the core do the irq_desc resolution.

No functional change.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NDavid Vrabel <david.vrabel@citrix.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Xen <xen-devel@lists.xenproject.org>
Cc: x86 <x86@kernel.org>
Link: http://lkml.kernel.org/r/20140223212737.869264085@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Let the core do the irq_desc resolution.

No functional change.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: David S. Miller <davem@davemloft.net>
Link: http://lkml.kernel.org/r/20140223212737.635609567@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Let the core do the irq_desc resolution.

No functional change.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: mips <inux-mips@linux-mips.org>
Link: http://lkml.kernel.org/r/20140223212737.517340416@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

There is a common pattern all over the place:

      kstat_incr_irqs_this_cpu(irq, irq_to_desc(irq));

This results in a call to core code anyway. So provide a function
which does the same thing in core.

While at it, replace the butt ugly macro with an inline.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140223212737.422068876@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Warn if any PIRQ cannot be bound to an event channel. Remove the check
for irq_desc->action. This hypercall never fails in practice so we can
emit a warning unconditionally.

Remove a check for a valid irq desc. The only caller of
xen_destroy_irq() will only do so if the irq was previously fully
setup, which means the descriptor has been allocated as well.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Xen <xen-devel@lists.xenproject.org>
Cc: David Vrabel <david.vrabel@citrix.com>
Link: http://lkml.kernel.org/r/20140223212738.579581220@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

generic_handler_irq() already tests for !desc so use this instead of
generic_handle_irq_desc().

Use irq_get_irq_data() instead of desc->irq_data.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NDavid Vrabel <david.vrabel@citrix.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Xen <xen-devel@lists.xenproject.org>
Link: http://lkml.kernel.org/r/20140223212738.222412125@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

The pm-mmp2 and pm-pxa910 power management related irq_set_wake
callbacks fiddle pointlessly with the irq actions for no reason except
for lack of understanding how the wakeup mechanism works.

On supsend the core disables all interrupts lazily, i.e. it does not
mask them at the irq controller level. So any interrupt which is
firing during suspend will mark the corresponding interrupt line as
pending. Just before the core powers down it checks whether there are
interrupts pending from interrupt lines which are marked as wakeup
sources and if so it aborts the suspend and resends the interrupts.
If there was no interrupt at this point, the cpu goes into suspend
with these interrupts unmasked.

The IRQF_NO_SUSPEND flag for interrupt actions is a totally different
mechanism. That allows the device driver to prevent the core from
disabling the interrupt despite the fact that it is not marked as a
wakeup source. This has nothing to do with the case at hand. It was
introduced for special cases where lazy disable is not possible.

Remove the nonsense along with the braindamaged boundary check. The
core code does NOT call these functions out of boundary.

Add a FIXME comment to an unhandled error path which merily printks
some useless blurb instead of returning a proper error code.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: arm <linux-arm-kernel@lists.infradead.org>
Cc: Eric Miao <eric.y.miao@gmail.com>
Cc: Haojian Zhuang <haojian.zhuang@gmail.com>
Cc: Russell King <linux@arm.linux.org.uk>
Link: http://lkml.kernel.org/r/20140223212737.214342433@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Use the proper functions. There is no need to fiddle with irq_desc.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: Shawn Guo <shawn.guo@linaro.org>C
Acked-by: NTony Lindgren <tony@atomide.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: arm <linux-arm-kernel@lists.infradead.org>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Link: http://lkml.kernel.org/r/20140223212737.099151500@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

There is no reason to care about irq_desc in that context, escpecially
as irq_data for that interrupt is retrieved as well.

Use the proper accessor for the msi descriptor
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Acked-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NJingoo Han <jg1.han@samsung.com>
Cc: Mohit Kumar <mohit.kumar@st.com>
Cc: pci <linux-pci@vger.kernel.org>
Link: http://lkml.kernel.org/r/20140223212736.987803648@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

commit 91150af3 (powerpc/eeh: Fix unbalanced enable for IRQ) is
another brilliant example of trainwreck engineering.

The patch "fixes" the issue of an unbalanced call to irq_enable()
which causes a prominent warning by checking the disabled state of the
interrupt line and call conditionally into the core code.

This is wrong in two aspects:

1) The warning is there to tell users, that they need to fix their
   asymetric enable/disable patterns by finding the root cause and
   solving it there.

   It's definitely not meant to work around it by conditionally
   calling into the core code depending on the random state of the irq
   line.

   Asymetric irq_disable/enable calls are a clear sign of wrong usage
   of the interfaces which have to be cured at the root and not by
   somehow hacking around it.

2) The abuse of core internal data structure instead of using the
   proper interfaces for retrieving the information for the 'hack
   around'

   irq_desc is core internal and it's clear enough stated.

Replace at least the irq_desc abuse with the proper functions and add
a big fat comment why this is absurd and completely wrong.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Gavin Shan <shangw@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: ppc <linuxppc-dev@lists.ozlabs.org>
Link: http://lkml.kernel.org/r/20140223212736.562906212@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

No functional change
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: ppc <linuxppc-dev@lists.ozlabs.org>
Link: http://lkml.kernel.org/r/20140223212736.333718121@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

I'm really grumpy about this one. The line:

#include "../../../kernel/irq/settings.h"

should have been an alarm sign for all people who added their SOB to
this trainwreck.

When I cleaned up the mess people made with interrupt descriptors a
few years ago, I warned that I'm going to hunt down new offenders and
treat them with stinking trouts. In this case I'll use frozen shark
for a better educational value.

The whole idiocy which was done there could have been avoided with two
lines of perfectly fine code. And do not complain about the lack of
correct examples in tree.

The solution is simple:

  Remove the brainfart and use the proper functions, which should
  have been used in the first place
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Ashish Kalra <ashish.kalra@freescale.com>
Cc: Timur Tabi <timur@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: ppc <linuxppc-dev@lists.ozlabs.org>
Link: http://lkml.kernel.org/r/20140223212736.451970660@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

This reverts commit 40b367d9.

Russell King has raised the idea of creating a proper PMU driver for
this SoC that would incorporate the functionality currently in this
driver. It would also cover the use case for the graphics subsystem on
this SoC.

To prevent having to maintain the devicetree ABI for this limited
interrupt-handler driver, we revert the driver before it hits a mainline
tagged release (eg v3.15).
Signed-off-by: NJason Cooper <jason@lakedaemon.net>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Sebastian Hesselbarth <sebastian.hesselbarth@googlemail.com>
Cc: Gregory CLEMENT <gregory.clement@free-electrons.com>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
Link: http://lkml.kernel.org/r/1393911160-7688-1-git-send-email-jason@lakedaemon.netSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

irqchip mvebu changes for v3.15

 - armada-370-xp
    - add MSI helper
    - MPIC chained handler
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

The new Armada 375 and Armada 38x Marvell SoCs are based on Cortex-A9
CPU cores and use the ARM GIC as their main interrupt controller.
However, for various purposes (wake-up from suspend, MSI interrupts),
they have kept a separate MPIC interrupt controller, acting as a slave
to the GIC. This MPIC was already used as the primary controller on
previous Marvell SoCs, so this commit extends the existing driver to
allow the MPIC to be used as a GIC slave.
Reviewed-by: NGregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: NEzequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: NJason Cooper <jason@lakedaemon.net>

Introduce a helper function to handle the MSI interrupts. This makes
the code more readable. In addition, this will allow to introduce a
chained IRQ handler mechanism, which is needed in situations where the
MPIC is used as a slave to another interrupt controller.
Reviewed-by: NGregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: NEzequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: NJason Cooper <jason@lakedaemon.net>