The current PCI/MSI support in the GICv3 ITS doesn't really deal
with systems where different PCI devices end-up using the same
RequesterID (as it would be the case with non-transparent bridges,
for example). It is likely that none of these devices would
actually generate any interrupt, as the ITS is programmed with
the device's own ID, and not that of the bridge.

A solution to this is to iterate over the PCI hierarchy to
discover what the device aliases too. We also use this
to discover the upper bound of the number of MSIs that this
sub-hierarchy can generate.

With this in place, PCI aliases can be supported.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/1425659870-11832-4-git-send-email-marc.zyngier@arm.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

The ITS table allocator is only allocating a single page per table.
This works fine for most things, but leads to silent lack of
interrupt delivery if we end-up with a device that has an ID that is
out of the range defined by a single page of memory. Even worse, depending
on the page size, behaviour changes, which is not a very good experience.

A solution is actually to allocate memory for the full range of ID that
the ITS supports. A massive waste memory wise, but at least a safe bet.

Tested on a Phytium SoC.
Tested-by: NChen Baozi <chenbaozi@kylinos.com.cn>
Acked-by: NChen Baozi <chenbaozi@kylinos.com.cn>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/1425659870-11832-3-git-send-email-marc.zyngier@arm.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

We skip initialisation of ITS in case the device-tree has no
corresponding description, but we are still accessing to ITS bits while
setting CPU interface what leads to the kernel panic:

ITS: No ITS available, not enabling LPIs
CPU0: found redistributor 0 region 0:0x000000002f100000
Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = ffffffc0007fb000
[00000000] *pgd=00000000fc407003, *pud=00000000fc407003, *pmd=00000000fc408003, *pte=006000002f000707
Internal error: Oops: 96000005 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.19.0-rc2+ #318
Hardware name: FVP Base (DT)
task: ffffffc00077edb0 ti: ffffffc00076c000 task.ti: ffffffc00076c000
PC is at its_cpu_init+0x2c/0x320
LR is at gic_cpu_init+0x168/0x1bc

It happens in gic_rdists_supports_plpis() because gic_rdists is NULL.
The gic_rdists is set to non-NULL only when ITS node is presented in
the device-tree.

Fix this by moving the call to gic_rdists_supports_plpis() inside the
!list_empty(&its_nodes) block, because it is that list that guards the
validity of the rest of the information in this driver.
Acked-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NVladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/1425659870-11832-2-git-send-email-marc.zyngier@arm.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

The cevt-r4k driver used to call into the GIC driver to find whether the
timer was pending, but only with External Interrupt Controller (EIC)
mode, where the Cause.IP bits can't be used as they encode the interrupt
priority level (Cause.RIPL) instead.

However commit e9de688d ("irqchip: mips-gic: Support local
interrupts") changed the condition from cpu_has_veic to gic_present.
This fails on cores such as P5600 which have a GIC but the local
interrupts aren't routable by the GIC, causing c0_compare_int_usable()
to consider the interrupt unusable so r4k_clockevent_init() fails.

The previous behaviour, added in commit 98b67c37 ("MIPS: Add EIC
support for GIC."), wasn't really correct either as far as I can tell,
since P5600 apparently supports EIC mode too, and in any case the use of
Cause.TI with r2 should have been sufficient anyway since commit
010c108d ("MIPS: PowerTV: Fix support for timer interrupts with > 64
external IRQs").

Therefore drop the call into the gic driver altogether, and add a
comment in c0_compare_int_pending() to clarify that Cause.TI does get
checked since MIPS r2.
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
Fixes: e9de688d ("irqchip: mips-gic: Support local interrupts")
Reviewed-by: NAndrew Bresticker <abrestic@chromium.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Steven J. Hill <steven.hill@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9077/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Commit e9de688d ("irqchip: mips-gic: Support local interrupts")
changed the GIC irqchip driver so that all local interrupts were routed
to the same CPU pin used for external interrupts. Unfortunately this
causes a regression when smp-cmp is used. The CPUs are started by the
bootloader and put in a timer based waiting poll loop, but when their
timer interrupts are rerouted to a different IRQ pin which is not
unmasked they never wake up.

Since smp-cmp support is deprecated and everybody who was using it
should be switching to smp-cps which brings up the secondary CPUs
without bootloader assistance, I've gone for the simple fix which can be
easily removed once smp-cmp is removed, rather than a fully generic fix.

In __gic_init() the local GIC_VPE_TIMER_MAP register is read to find the
boot-time routing of the local timer interrupt, and a chained handler is
added to that CPU pin as well as the normal one.
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
Fixes: e9de688d ("irqchip: mips-gic: Support local interrupts")
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Reviewed-by: NAndrew Bresticker <abrestic@chromium.org>
Patchwork: https://patchwork.linux-mips.org/patch/9081/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

During a recent cleanup of the arm64 DTs it has become clear that
the handling of PPIs in xxxx_set_type() is incorrect. The ARM TRMs
for GICv2 and later allow for "implementation defined" support for
setting the edge or level type of the PPI interrupts and don't restrict
the activation level of the signal. Current ARM implementations
do restrict the PPI level type to IRQ_TYPE_LEVEL_LOW, but licensees
of the IP can decide to shoot themselves in the foot at any time.
Signed-off-by: NLiviu Dudau <Liviu.Dudau@arm.com>
Acked-by: NMarc Zyngier <Marc.Zyngier@arm.com>
Cc: LAKML <linux-arm-kernel@lists.infradead.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Haojian Zhuang <haojian.zhuang@linaro.org>
Link: http://lkml.kernel.org/r/1421772779-25764-1-git-send-email-Liviu.Dudau@arm.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

When an interrupt occurs __gic_irq_dispatch() continuously reads local
and shared pending registers until all is serviced before
returning. The problem with that is that it could introduce a long
delay before returning if a piece of hardware keeps triggering while
in one of these loops.

To ensure fairness and priority doesn't get skewed a lot, read local
and shared pending registers once to service each pending IRQ once.
If another interupt triggers while servicing the current ones, then we
shall re-enter the handler after we return.
Signed-off-by: NQais Yousef <qais.yousef@imgtec.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: <linux-mips@linux-mips.org>
Link: http://lkml.kernel.org/r/1421668289-828-1-git-send-email-qais.yousef@imgtec.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Add interrupt controller driver to the Conexant CX92755 SoC, part of the
Digicolor SoCs series. Use the generic irq framework support. Use syscon to
access the system global UC_IRQ_CONTROL register.
Signed-off-by: NBaruch Siach <baruch@tkos.co.il>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/5b769e3c23dfa5fde08c4f3bc966c2c2b3921d8a.1421317616.git.baruch@tkos.co.ilSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Nowadays omap2 is booting in device tree only mode so there is no
need to keep the legacy interface around for omap2_init_irq().
Signed-off-by: NTony Lindgren <tony@atomide.com>
Reviewed-by: NFelipe Balbi <balbi@ti.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1421187806-6804-3-git-send-email-tony@atomide.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

On dm81xx we have 128 interrupts like am33xx has. Let's add
compatible flags for dm814x and dm816x, and document the
existing binding.

As the dm81xx are booting in device tree only mode, we can now
also remove ti81xx_init_irq() legacy function.
Signed-off-by: NTony Lindgren <tony@atomide.com>
Reviewed-by: NFelipe Balbi <balbi@ti.com>
Cc: Brian Hutchinson <b.hutchman@gmail.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1421187806-6804-2-git-send-email-tony@atomide.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Originally mtk-sysirq hardcoded supported irq number to 224. This
was fine since all SoCs before support the same number of irqs for
intpol.

However MT8173 intpol support 32 more irq pins, changes to get
irq number from register resource size to suppor MT8173 properly.
Signed-off-by: NYingjoe Chen <yingjoe.chen@mediatek.com>
Signed-off-by: NEddie Huang <eddie.huang@mediatek.com>
Cc: <srv_heupstream@mediatek.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
Cc: Kumar Gala <galak@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Olof  Johansson <olof@lixom.net>
Cc: Robert Richter <rrichter@cavium.com>
Cc: Mark Brown <broonie@linaro.org>
Cc: <linux-arm-kernel@lists.infradead.org>
Cc: Sascha Hauer <kernel@pengutronix.de>
Cc: <marc.zyngier@arm.com>
Cc: <peter.maydell@linaro.org>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1421054073-43468-3-git-send-email-eddie.huang@mediatek.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Add r8a7779 specific support for IRLM bit configuration
in the INTC-IRQPIN driver. Without this code we need
special workaround code in arch/arm/mach-shmobile.

The IRLM bit for the INTC hardware exists on various
older SH-based SoCs and is used to select between two
modes for the external interrupt pins IRQ0 to IRQ3:

IRLM = 0: (default from reset on r8a7779)
In this mode the pins IRQ0 to IRQ3 are used together
to give a value between 0 and 15 to the SoC. External
logic is required for masking. This mode is not
supported by the INTC-IRQPIN driver.

IRLM = 1: (needs this patch or configuration elsewhere)
In this mode IRQ0 to IRQ3 operate as 4 individual
external interrupt pins. In this mode the SMSC ethernet
chip can be used via IRQ1 on r8a7779 Marzen. This mode
is the only supported mode by the INTC-IRQPIN driver.

For this patch to work the r8a7779 DTS needs to pass
the ICR0 register as the last register bank.
Signed-off-by: NMagnus Damm <damm+renesas@opensource.se>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: horms@verge.net.au
Cc: jason@lakedaemon.net
Link: http://lkml.kernel.org/r/20141203121803.5936.35881.sendpatchset@w520Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

The gic_send_sgi() function used hardcoded bit shift values to
generate the ICC_SGI1R_EL1 register value.
Replace this with symbolic names to allow reusing them later.
Signed-off-by: NAndre Przywara <andre.przywara@arm.com>
Reviewed-by: NChristoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: NChristoffer Dall <christoffer.dall@linaro.org>

This patch makes the bitmask for AIC_SRCTYPE consistent
with that of its valid values, and prevents the priority
field at bits 2:0 from being clobbered by an incorrect
AND with the AIC_SRCTYPE mask.
Signed-off-by: NGavin Li <gavinli@thegavinli.com>
Cc: <stable@vger.kernel.org> # v3.17+
Acked-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Link: https://lkml.kernel.org/r/1420598843-8409-1-git-send-email-gavinli@thegavinli.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

commit 55601c9f (arm: omap: intc: switch over
to linear irq domain) introduced a regression with
SDMA legacy driver because that driver strictly depends
on INTC's IRQs starting at NR_IRQs. Aparently
irq_domain_add_linear() won't guarantee that, since we see
a 7 IRQs difference when booting with and without the
commit cited above.

Until arch/arm/plat-omap/dma.c is properly fixed, we
must maintain OMAP2/3 using irq_domain_add_legacy().

A FIXME note was added so people know to delete that
code once that legacy DMA driver is fixed up.

Fixes: 55601c9f (arm: omap: intc: switch over to linear irq domain)
Cc: <stable@vger.kernel.org> # v3.18
Tested-by: NAaro Koskinen <aaro.koskinen@iki.fi>
Tested-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Link: https://lkml.kernel.org/r/1420576688-10604-1-git-send-email-balbi@ti.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

arm64 defconfig spits out the following compiler warning from the ITS
driver:

In file included from include/linux/bitmap.h:9:0,
                 from drivers/irqchip/irq-gic-v3-its.c:18:
drivers/irqchip/irq-gic-v3-its.c: In function ‘its_create_device’:
include/linux/kernel.h:716:17: warning: comparison of distinct pointer types lacks a cast
  (void) (&_max1 == &_max2);  \
                 ^
drivers/irqchip/irq-gic-v3-its.c:1056:12: note: in expansion of macro ‘max’
  nr_ites = max(2, roundup_pow_of_two(nvecs));

Fix the warning by specifying the decimal constant `2' explicitly as an
unsigned long type.

Cc: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Acked-by: NMarc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/1418825469-30529-1-git-send-email-will.deacon@arm.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

HiP04 GIC extends to support 16 cores, so we should
initialize the hip04_cpu_map to 0xffff.
Signed-off-by: NWang Long <long.wanglong@huawei.com>
Acked-by: NHaojian Zhuang <haojian.zhuang@linaro.org>
Link: https://lkml.kernel.org/r/1418295816-179583-1-git-send-email-long.wanglong@huawei.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

Beniamino noticed a bug that an invalid DT file for the mediatek interrupt
polarity extension will cause kernel oops.

The reason is that the interrupt polarity support for mediatek chips
merely checks for NULL pointer instead of a casted error return
value in mtk_sysirq_of_init() so any other casted error value passes
the NULL pointer check and causes a kernel panic when dereferenced.

Use IS_ERR() and return the error value via PTR_ERR().

[ jac: took V2 over V3 for diff formatting, hand-added V3 changes,
tweaked subject line. ]
Reported-by: NBeniamino Galvani <b.galvani@gmail.com>
Signed-off-by: NYingjoe Chen <yingjoe.chen@mediatek.com>
Link: https://lkml.kernel.org/r/1418205302-22531-1-git-send-email-yingjoe.chen@mediatek.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

When issuing a MAPD command, one of the parameters passed to the ITS
is the number of EventID bits used to index the per-device Interrupt
Translation Table (ITT). Crucially, this is the number of bits
*minus one*.

This has two consequences:
- The size of the ITT has to be a strict power of two, no matter
  how many different events the device is actually going to generate.
- It is impossible to express an ITT with a single entry, as you
  would have to tell the ITS to "use zero bit from the EventID",
  and that clashes with "minus one" above.

Fix this by allocating the ITT with the number of vectors rounded up
to the next power of two, with a minimum of two entries.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Yun Wu (Abel) <wuyun.wu@huawei.com>
Cc: Robert Richter <robert.richter@caviumnetworks.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

The ITS code could do a bit less in the alloc/free paths, and a bit
more in the activate/deactivate methods, giving a better separation
between software allocation and HW programing.
Suggested-by: NWuyun Wu (Abel) <wuyun.wu@huawei.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Yun Wu (Abel) <wuyun.wu@huawei.com>
Cc: Robert Richter <robert.richter@caviumnetworks.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Fix stupid thinko on the path freeing the interrupts, where only
the first interrupt would get reset, and none of the others.

This should only affect multi-MSI allocations.
Reported-by: NWuyun Wu (Abel) <wuyun.wu@huawei.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Robert Richter <robert.richter@caviumnetworks.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

This commit adds suspend/resume support to the irqchip driver used on
Armada XP platforms (amongst others). It does so by adding a set of
suspend/resume syscore_ops, that will respectively save and restore
the necessary registers to ensure interrupts continue to work after
resume.

It is worth mentioning that the affinity is lost during a
suspend/resume cycle, because when a secondary CPU is brought
off-line, all interrupts that are assigned to this CPU in terms of
affinity gets re-assigned to a still running CPU. Therefore, right
before entering suspend, all interrupts are assigned to the boot CPU.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: linux-kernel@vger.kernel.org
Link: https://lkml.kernel.org/r/1416585613-2113-4-git-send-email-thomas.petazzoni@free-electrons.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

This patch adds in support for S2R for dw-apb-ictl irqchip driver.

We can used relaxed variants in the resume hook because there's no DMA
at all here, the device type memory attribute can ensure the operations
order and relaxed version imply compiler barrier.
Signed-off-by: NJisheng Zhang <jszhang@marvell.com>
Link: https://lkml.kernel.org/r/1415773374-4629-4-git-send-email-jszhang@marvell.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

The irq_chip_type instances have separate mask registers, so we need to
enable IRQ_GC_MASK_CACHE_PER_TYPE to actually handle separate mask registers.
Signed-off-by: NJisheng Zhang <jszhang@marvell.com>
Acked-by: NSebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Link: https://lkml.kernel.org/r/1415773374-4629-3-git-send-email-jszhang@marvell.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

There's no DMA at all, the device type memory attribute can ensure the
operations order and relaxed version imply compiler barrier, so we are safe
to use relaxed version to improve the performance a bit.
Signed-off-by: NJisheng Zhang <jszhang@marvell.com>
Acked-by: NSebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Link: https://lkml.kernel.org/r/1415773374-4629-2-git-send-email-jszhang@marvell.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

ARM GICv2m specification extends GICv2 to support MSI(-X) with
a new register frame. This allows a GICv2 based system to support
MSI with minimal changes.
Signed-off-by: NSuravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
[maz: converted the driver to use stacked irq domains,
      updated changelog]
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/1416941243-7181-2-git-send-email-marc.zyngier@arm.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

Mediatek SoCs have interrupt polarity support in sysirq which
allows to invert polarity for given interrupt. Add this support
using hierarchy irq domain.
Signed-off-by: NYingjoe Chen <yingjoe.chen@mediatek.com>
Link: https://lkml.kernel.org/r/1416902662-19281-3-git-send-email-yingjoe.chen@mediatek.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

Add support to use gic as a parent for stacked irq domain.
Signed-off-by: NYingjoe Chen <yingjoe.chen@mediatek.com>
Acked-by: NMarc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/1416902662-19281-2-git-send-email-yingjoe.chen@mediatek.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

Get the show on the road...
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/1416839720-18400-13-git-send-email-marc.zyngier@arm.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

As the ITS is always a subsystem if GICv3, its probing/init is
driven by the main GICv3 code.

Plug that code in (guarded by a config option).
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/1416839720-18400-12-git-send-email-marc.zyngier@arm.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

Add the code that probes the ITS from the device tree,
and initialize it.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/1416839720-18400-11-git-send-email-marc.zyngier@arm.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

Now, the bit of code that allow us to use the ITS as a MSI controller.
Both MSI and MSI-X are supported.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/1416839720-18400-10-git-send-email-marc.zyngier@arm.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

The ITS has a notion of "device" that can write to it in order to
generate an interrupt.

Conversly, the driver maintains a per-ITS list of devices, together
with their configuration information, and uses this to configure
the HW.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/1416839720-18400-9-git-send-email-marc.zyngier@arm.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

The interrupt translation is driven by a set of tables (device,
ITT, and collection) to be in the end delivered to a CPU. Also,
the redistributors rely on a couple of tables (configuration, and
pending) to deliver the interrupts to the CPUs.

This patch adds the required allocators for these tables.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/1416839720-18400-8-git-send-email-marc.zyngier@arm.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

LPIs are the type of interrupts that are used by the ITS. Given
the size of the namespace (anywhere between 16 and 32bit), interrupt
IDs are allocated in chunks of 32.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/1416839720-18400-7-git-send-email-marc.zyngier@arm.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

The usual methods that are used to present an irqchip to the rest
of the kernel
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/1416839720-18400-6-git-send-email-marc.zyngier@arm.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

The ITS is configured through a number commands that the driver
issues to the HW using a memory-based circular buffer.

This patch implements the subset of commands that are required
for Linux.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/1416839720-18400-5-git-send-email-marc.zyngier@arm.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

The basic GICv3 driver has almost no use for the redistributor
(other than the basic per-CPU interrupts), but the ITS needs
a lot more from them.

As such, rework the set of data structures. The behaviour of the
GICv3 driver is otherwise unaffected.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/1416839720-18400-4-git-send-email-marc.zyngier@arm.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

In order to start supporting stacked domains, convert the GICv3
code base to the new domain hierarchy framework, which mostly
amounts to supporting the new alloc/free callbacks.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/1416839720-18400-3-git-send-email-marc.zyngier@arm.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

Return value of irq_of_parse_and_map() is unsigned int, with 0
indicating failure, so testing for negative result never works.
Signed-off-by: NDmitry Torokhov <dtor@chromium.org>
Acked-by: NFlorian Fainelli <f.fainelli@gmail.com>
Tested-by: Kevin Cernekee <cernekee@gmail.com> 
Link: https://lkml.kernel.org/r/20141114221642.GA37468@dtor-wsSigned-off-by: NJason Cooper <jason@lakedaemon.net>