Move the code that sets-up a GIC via device-tree into it's own
function and add a generic function for GIC teardown that can be used
for both device-tree and ACPI to unmap the GIC memory.
Signed-off-by: NJon Hunter <jonathanh@nvidia.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Store the GIC configuration parameters in the GIC chip data structure.
This will allow us to simplify the code by reducing the number of
parameters passed between functions.

Update the __gic_init_bases() function so that we only need to pass a
pointer to the GIC chip data structure and no longer need to pass the
GIC index in order to look-up the chip data.
Signed-off-by: NJon Hunter <jonathanh@nvidia.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Instead of passing the GIC index to the save/restore functions pass a
pointer to the GIC chip data. This will allow these save/restore
functions to be re-used by a platform driver where the GIC chip data
structure is allocated dynamically and so there is no applicable index
for identifying the GIC.
Signed-off-by: NJon Hunter <jonathanh@nvidia.com>
Acked-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

If the GIC initialisation fails, then currently we do not return an error
or clean-up afterwards. Although for root controllers, this failure may be
fatal anyway, for secondary controllers, it may not be fatal and so return
an error on failure and clean-up.

Update the functions gic_cpu_init() and gic_pm_init() to return an error
instead of calling BUG() and perform any necessary clean-up.

For non-banked GIC controllers, make sure that we free any memory
allocated if we fail to initialise the IRQ domain. Please note that
free_percpu() only frees memory if the pointer passed to it is not NULL
and so it is unnecessary to check if both pointers are valid or not.
Signed-off-by: NJon Hunter <jonathanh@nvidia.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

There are only 3 differences (not including the name) in the definitions
of the gic_chip and gic_eoimode1_chip structures. Instead of statically
defining the gic_eoimode1_chip structure, remove it and populate the
eoimode1 functions dynamically for the appropriate GIC irqchips.
Signed-off-by: NJon Hunter <jonathanh@nvidia.com>
Acked-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

If we fail to map the address space for the GIC distributor or CPU
interface, then don't attempt to initialise the chip, just WARN and
return.
Signed-off-by: NJon Hunter <jonathanh@nvidia.com>
Acked-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

When an IPI is generated by a CPU, the pattern looks roughly like:

  <write shared data>
  smp_wmb();
  <write to GIC to signal SGI>

On the receiving CPU we rely on the fact that, once we've taken the
interrupt, then the freshly written shared data must be visible to us.
Put another way, the CPU isn't going to speculate taking an interrupt.

Unfortunately, this assumption turns out to be broken.

Consider that CPUx wants to send an IPI to CPUy, which will cause CPUy
to read some shared_data. Before CPUx has done anything, a random
peripheral raises an IRQ to the GIC and the IRQ line on CPUy is raised.
CPUy then takes the IRQ and starts executing the entry code, heading
towards gic_handle_irq. Furthermore, let's assume that a bunch of the
previous interrupts handled by CPUy were SGIs, so the branch predictor
kicks in and speculates that irqnr will be <16 and we're likely to
head into handle_IPI. The prefetcher then grabs a speculative copy of
shared_data which contains a stale value.

Meanwhile, CPUx gets round to updating shared_data and asking the GIC
to send an SGI to CPUy. Internally, the GIC decides that the SGI is
more important than the peripheral interrupt (which hasn't yet been
ACKed) but doesn't need to do anything to CPUy, because the IRQ line
is already raised.

CPUy then reads the ACK register on the GIC, sees the SGI value which
confirms the branch prediction and we end up with a stale shared_data
value.

This patch fixes the problem by adding an smp_rmb() to the IPI entry
code in gic_handle_irq. As it turns out, the combination of a control
dependency and an ISB instruction from the EOI in the GICv3 driver is
enough to provide the ordering we need, so we add a comment there
justifying the absence of an explicit smp_rmb().

Cc: stable@vger.kernel.org
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

For now, the firmware tables are parsed 2 times: once in the GIC
drivers, the other timer when initializing the vGIC. It means code
duplication and make more tedious to add the support for another
firmware table (like ACPI).

Introduce a new structure and set of helpers to get/set the virtual GIC
information. Also fill up the structure for GICv2.
Signed-off-by: NJulien Grall <julien.grall@arm.com>
Signed-off-by: NChristoffer Dall <christoffer.dall@linaro.org>

The ACPI code requires to use global variables in order to collect
information from the tables.

For now, a single global variable is used, but more will be added in a
subsequent patch. To make clear they are ACPI specific, gather all the
information in a single structure.
Signed-off-by: NJulien Grall <julien.grall@arm.com>
Acked-by: NChristofer Dall <christoffer.dall@linaro.org>
Acked-by: NHanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: NChristoffer Dall <christoffer.dall@linaro.org>

When introducing the whole CPU feature detection framework,
we lost the capability to detect a mismatched GIC configuration
(using the GICv2 MMIO interface, but having the system register
interface enabled).

In order to solve this, use the new this_cpu_has_cap() helper.
Also move the check to the CPU interface path in order to catch
systems where the first CPU has been correctly configured,
but the secondaries are not.
Reviewed-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NSuzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Moving an SPI around doesn't require any extra work from the rest
of the stack, and specially not for MSI-generated SPIs.

It is then worth returning IRQ_SET_MASK_OK_DONE instead of
IRQ_SET_MASK_OK, and simplify the other irqchips that rely on
this behaviour (GICv2m and Marvell's ODMI controller).
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Acked-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>
Link: https://lkml.kernel.org/r/1455894029-17270-1-git-send-email-marc.zyngier@arm.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

EOImode1 is only used for the root controller and hence only the root
controller uses the eoimode1 functions for handling interrupts. However,
if the root controller supports EOImode1, then the EOImodeNS bit will be
set for all GICs, enabling EOImode1. This is not what we want and this
causes interrupts on non-root GICs to only be dropped in priority but
never deactivated. Therefore, only set the EOImodeNS bit for the root
controller.
Acked-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NJon Hunter <jonathanh@nvidia.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Setting the affinity of an IRQ, it only applicable for the root
interrupt controller and so only populate this operator for the root
controller.
Acked-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NJon Hunter <jonathanh@nvidia.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

This patch introduces gicv2m_acpi_init(), which uses information
in MADT GIC MSI frames structure to initialize GICv2m driver.
It also exposes gicv2m_init() function, which simplifies callers
to a single GICv2m init function.
Reviewed-by: NMarc Zyngier <marc.zyngier@arm.com>
Tested-by: NDuc Dang <dhdang@apm.com>
Acked-by: NRafael J. Wysocki <rjw@rjwysocki.net>
Signed-off-by: NSuravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: NHanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Since there will be several places checking if fwnode.type
is equal FWNODE_IRQCHIP, this patch adds a convenient function
for this purpose.
Acked-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NSuravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

There is currently a hack in the GIC driver making it possible
to pass the number of GIC instances from the platform-specific
include files and thus override the variable MAX_GIC_NR.

With multiplatform deployments, this will not work as we need
to get rid of the platform-specific include files.

It turns out that this feature is only used by the RealView
platform which has a cascaded GIC. So move the configuration
to Kconfig and bump to 2 instances if we're building for the
RealView. The include file hacks can then be removed.

Tested on the ARM PB11MPCore with its cascaded GIC.
Suggested-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

The GIC has no such thing as interrupt 1020: the last valid ID is
1019, and the range 1020-1023 is reserved - 1023 indicating that
no interrupt is pending. So let's make sure we don't try to handle
this ID.

This bug has been in since the initial GIC code was introduced in
8ad68bbf ("[ARM] Add support for ARM RealView board").
Reported-by: NEric Auger <eric.auger@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Instead of having the irqchip being a static struct, make it part
of the per-instance data so we can assign it a dynamic name. This
has the usable side effect of displaying the GIC with an instance
number as GIC0, GIC1 ... GICn in /proc/interrupts, which is helpful
when debugging cascaded GICs, such as on the ARM PB11MPCore.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

The ARM RealView PB11MPCore reference design has some special
bits in a system controller register to set up the GIC in one
of three modes: legacy, new with DCC, new without DCC. The
register is also used to enable FIQ.

Since the platform will not boot unless this register is set
up to "new with DCC" mode, we need a special quirk to be
compiled-in for the RealView platforms.

If we find the right compatible string on the GIC TestChip,
we enable this quirk by looking up the system controller and
enabling the special bits.

We depend on the CONFIG_REALVIEW_DT Kconfig symbol as the old
boardfile code has the same fix hardcoded, and this is only
needed for the attempts to modernize the RealView code using
device tree.

After fixing this, the PB11MPCore boots with device tree
only.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

When using EOImode==1, we may mark interrupts as being forwarded
to a virtual machine. In that case, the interrupt is left active
while being passed to the VM.

If we suspend the system before the VM has deactivated the interrupt,
the active state will be lost (which may be very annoying, as this
may result in spurious interrupts and a confused guest).

To avoid this, save and restore the active state together with the
rest of the GIC registers.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Cc: <linux-arm-kernel@lists.infradead.org>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Russell King <linux@arm.linux.org.uk>
Link: http://lkml.kernel.org/r/1447701208-18150-5-git-send-email-marc.zyngier@arm.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

When restoring the GIC state (after a suspend/resume cycle,
for example), the driver directly writes the 'enabled' state
it has saved by accessing GICD_ISENABLERn, which performs
an OR operation between the value present in the register
and the value we write.

If whatever code that has run before we reentered the kernel
has enabled an interrupt that was previously disabled, we won't
restore that disabled state.

Making sure we first clear the register (by writting to
GICD_ICENABLERn) before restoring the enabled state.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Cc: <linux-arm-kernel@lists.infradead.org>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Russell King <linux@arm.linux.org.uk>
Link: http://lkml.kernel.org/r/1447701208-18150-4-git-send-email-marc.zyngier@arm.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

We are now left with only two use models for the GIC driver:
- Via a firmware interface, which mandates a hierarchical domain,
  and the use of the 'translate' method
- The legacy platforms, which assume irq==hwirq, hence not using
  the 'xlate' method.

The logical conclusion is that we can now nuke the 'xlate' method
altogether.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Reviewed-and-tested-by: NHanjun Guo <hanjun.guo@linaro.org>
Tested-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: <linux-arm-kernel@lists.infradead.org>
Cc: Tomasz Nowicki <tomasz.nowicki@linaro.org>
Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Cc: Graeme Gregory <graeme@xora.org.uk>
Cc: Jake Oshins <jakeo@microsoft.com>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Link: http://lkml.kernel.org/r/1444737105-31573-14-git-send-email-marc.zyngier@arm.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Now that the basic ACPI GSI code is irq domain aware, make sure
that the ACPI support in the GIC doesn't pointlessly deviate from
the DT path.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Reviewed-and-tested-by: NHanjun Guo <hanjun.guo@linaro.org>
Tested-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: <linux-arm-kernel@lists.infradead.org>
Cc: Tomasz Nowicki <tomasz.nowicki@linaro.org>
Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Cc: Graeme Gregory <graeme@xora.org.uk>
Cc: Jake Oshins <jakeo@microsoft.com>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Link: http://lkml.kernel.org/r/1444737105-31573-13-git-send-email-marc.zyngier@arm.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Since nobody is using gic_init_bases anymore outside of the GIC
driver itself, let's do a bit of housekeeping and remove the now
useless entry point.

Only gic_init() is now exposed to the rest of the kernel for the
benefit of legacy systems.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Reviewed-and-tested-by: NHanjun Guo <hanjun.guo@linaro.org>
Tested-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: <linux-arm-kernel@lists.infradead.org>
Cc: Tomasz Nowicki <tomasz.nowicki@linaro.org>
Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Cc: Graeme Gregory <graeme@xora.org.uk>
Cc: Jake Oshins <jakeo@microsoft.com>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Link: http://lkml.kernel.org/r/1444737105-31573-12-git-send-email-marc.zyngier@arm.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Since we now have a generic data structure to express an
interrupt specifier, convert all hierarchical irqchips that
are OF based to use a fwnode_handle as part of their alloc
and xlate (which becomes translate) callbacks.

As most of these drivers have dependencies (they exchange IRQ
specifiers), change them all in a single, massive patch...
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Reviewed-and-tested-by: NHanjun Guo <hanjun.guo@linaro.org>
Tested-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: <linux-arm-kernel@lists.infradead.org>
Cc: Tomasz Nowicki <tomasz.nowicki@linaro.org>
Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Cc: Graeme Gregory <graeme@xora.org.uk>
Cc: Jake Oshins <jakeo@microsoft.com>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Link: http://lkml.kernel.org/r/1444737105-31573-6-git-send-email-marc.zyngier@arm.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

The struct irq_domain contains a "struct device_node *" field
(of_node) that is almost the only link between the irqdomain
and the device tree infrastructure.

In order to prepare for the removal of that field, convert all
users to use irq_domain_get_of_node() instead.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Reviewed-and-tested-by: NHanjun Guo <hanjun.guo@linaro.org>
Tested-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: <linux-arm-kernel@lists.infradead.org>
Cc: Tomasz Nowicki <tomasz.nowicki@linaro.org>
Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Cc: Graeme Gregory <graeme@xora.org.uk>
Cc: Jake Oshins <jakeo@microsoft.com>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Link: http://lkml.kernel.org/r/1444737105-31573-2-git-send-email-marc.zyngier@arm.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

When using a GICv3 in compatibility (v2) mode, having GICv3 system
register access enabled is not really compliant with the architecture.

Warn if the firmware (or the hypervisor) has been lazy.
Reviewed-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Now that we have a basic infrastructure to register irqchips and
call them on discovery of a matching entry in MADT, convert the
GIC driver to this new probing method.

It ends up being a code deletion party, which is a rather good thing.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Reviewed-by: NHanjun Guo <hanjun.guo@linaro.org>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Tested-by: NHanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Add support for the PrimeCell® Generic Interrupt Controller (PL390) to
the GIC DT bindings and driver.

Currently the GIC driver treats this GIC variant the same as other GIC
variants, but there are differences in hardware topology (e.g. clock
inputs).

Sort the list of compatible values while we're at it.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Acked-by: NRob Herring <robh+dt@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Kumar Gala <galak@codeaurora.org>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
Link: http://lkml.kernel.org/r/1442261204-30931-2-git-send-email-geert%2Brenesas@glider.beSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

set_irq_flags is ARM specific with custom flags which have genirq
equivalents. Convert drivers to use the genirq interfaces directly, so we
can kill off set_irq_flags. The translation of flags is as follows:

IRQF_VALID -> !IRQ_NOREQUEST
IRQF_PROBE -> !IRQ_NOPROBE
IRQF_NOAUTOEN -> IRQ_NOAUTOEN

For IRQs managed by an irqdomain, the irqdomain core code handles clearing
and setting IRQ_NOREQUEST already, so there is no need to do this in
.map() functions and we can simply remove the set_irq_flags calls. Some
users also modify IRQ_NOPROBE and this has been maintained although it
is not clear that is really needed. There appears to be a great deal of
blind copy and paste of this code.
Signed-off-by: NRob Herring <robh@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Kukjin Kim <kgene@kernel.org>
Cc: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Lee Jones <lee@kernel.org>
Cc: Alexander Shiyan <shc_work@mail.ru>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: linux-rpi-kernel@lists.infradead.org
Cc: linux-samsung-soc@vger.kernel.org
Link: http://lkml.kernel.org/r/1440889285-5637-3-git-send-email-robh@kernel.orgSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Most interrupt flow handlers do not use the irq argument. Those few
which use it can retrieve the irq number from the irq descriptor.

Remove the argument.

Search and replace was done with coccinelle and some extra helper
scripts around it. Thanks to Julia for her help!
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Jiang Liu <jiang.liu@linux.intel.com>

Get rid of the handler_data abuse.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NMarc Zyngier <marc.zyngier@arm.com>

The GICv2 architecture mandates that the two 4kB GIC regions are
contiguous, and on two separate physical pages (so that access to
the second page can be trapped by a hypervisor). This doesn't work
very well when PAGE_SIZE is 64kB.

A relatively common hack^Wway to work around this is to alias each
4kB region over its own 64kB page. Of course in this case, the base
address you want to use is not really the begining of the region,
but base + 60kB (so that you get a contiguous 8kB region over two
distinct pages).

Normally, this would be described in DT with a new property, but
some HW is already out there, and the firmware makes sure that
it will override whatever you put in the GIC node. Duh. And of course,
said firmware source code is not available, despite being based
on u-boot.

The workaround is to detect the case where the CPU interface size
is set to 128kB, and verify the aliasing by checking that the ID
register for GIC400 (which is the only GIC wired this way so far)
is the same at base and base + 0xF000. In this case, we update
the GIC base address and let it roll.

And if you feel slightly sick by looking at this, rest assured that
I do too...
Reported-by: NJulien Grall <julien.grall@citrix.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Stuart Yoder <stuart.yoder@freescale.com>
Cc: Pavel Fedin <p.fedin@samsung.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1442142873-20213-2-git-send-email-marc.zyngier@arm.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Non-DT/ACPI systems call directly into the GIC driver at init time.
Turns out 0b996fd3 ("irqchip/GIC: Convert to EOImode == 1")
breaks old non firmware-driven platforms, as the driver only
works out the capability of the platform on the DT/ACPI paths.

Fix this thinko by forcing EOImode==0 on non-DT platforms,
which are not capable of supporting a hypervisor anyway.
Reported-and-tested-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1441098533-31523-1-git-send-email-marc.zyngier@arm.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Commit 0a4377de ("genirq: Introduce irq_set_vcpu_affinity() to
target an interrupt to a VCPU") added just what we needed at the
lowest level to allow an interrupt to be deactivated by a guest.

When such a request reaches the GIC, it knows it doesn't need to
perform the deactivation anymore, and can safely leave the guest
do its magic. This of course requires additional support in both
VFIO and KVM.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Reviewed-and-tested-by: NEric Auger <eric.auger@linaro.org>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: <linux-arm-kernel@lists.infradead.org>
Cc: kvmarm@lists.cs.columbia.edu
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1440604845-28229-5-git-send-email-marc.zyngier@arm.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

So far, GICv2 has been used with EOImode == 0. The effect of this
mode is to perform the priority drop and the deactivation of the
interrupt at the same time.

While this works perfectly for Linux (we only have a single priority),
it causes issues when an interrupt is forwarded to a guest, and when
we want the guest to perform the EOI itself.

For this case, the GIC architecture provides EOImode == 1, where:
- A write to the EOI register drops the priority of the interrupt
  and leaves it active. Other interrupts at the same priority level
  can now be taken, but the active interrupt cannot be taken again
- A write to the DIR marks the interrupt as inactive, meaning it can
  now be taken again.

We only enable this feature when booted in HYP mode and that
the device-tree reported a suitable CPU interface. Observable behaviour
should remain unchanged.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Reviewed-and-tested-by: NEric Auger <eric.auger@linaro.org>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: <linux-arm-kernel@lists.infradead.org>
Cc: kvmarm@lists.cs.columbia.edu
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1440604845-28229-4-git-send-email-marc.zyngier@arm.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Commit 32289506 ("irqchip: gic: Preserve gic V2 bypass bits in cpu
ctrl register") added a new function, gic_cpu_if_up(), to program the
GIC CPU_CTRL register. This function assumes that there is only one GIC
instance present and hence always uses the chip data for the primary GIC
controller. Although it is not common for there to be a secondary, some
devices do support a secondary. Therefore, fix this by passing
gic_cpu_if_up() a pointer to the appropriate chip data structure.

Similarly, the function gic_cpu_if_down() only assumes that there is a
single GIC instance present. Update this function so that an instance
number is passed for the appropriate GIC and return an error code on
failure. The vexpress TC2 (which has a single GIC) is currently the only
user of this function and so update it accordingly. Note that because the
TC2 only has a single GIC, the call to gic_cpu_if_down() should always
be successful.
Signed-off-by: NJon Hunter <jonathanh@nvidia.com>
Reviewed-by: NMarc Zyngier <marc.zyngier@arm.com>
Cc: <linux-arm-kernel@lists.infradead.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1438332252-25248-2-git-send-email-jonathanh@nvidia.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

The gic_init_bases() function initialises an array that stores the mapping
between the GIC and CPUs. This array is a global array that is
unconditionally initialised on every call to gic_init_bases(). Although,
it is not common for there to be more than one GIC instance, there are
some devices that do support nested GIC controllers and gic_init_bases()
can be called more than once.

A 2nd call to gic_init_bases() will clear the previous CPU mapping and
will only setup the mapping again for the CPU calling gic_init_bases().
Fix this by only allowing the CPU map to be configured for the primary GIC.

For secondary GICs the CPU map is not relevant because these GICs do not
directly route the interrupts to the main CPU(s) but to other GICs or
devices.
Signed-off-by: NJon Hunter <jonathanh@nvidia.com>
Reviewed-by: NMarc Zyngier <marc.zyngier@arm.com>
Cc: <linux-arm-kernel@lists.infradead.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1438332252-25248-1-git-send-email-jonathanh@nvidia.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Now that the GIC chip implementation enables IRQCHIP_SKIP_SET_WAKE and
IRQCHIP_MASK_ON_SUSPEND by default, the platforms requiring them need
not override the irqchip flags as before.

This patch removes all the users of gic_set_irqchip_flags and the
function itself.
Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Simon Horman <horms@verge.net.au>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Gregory CLEMENT <gregory.clement@free-electrons.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1436971109-20189-2-git-send-email-sudeep.holla@arm.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

The GIC controller doesn't provides any facility to configure the wakeup
sources. For the same reason, GIC chip implementation can't provide
irq_set_wake functionality, but that results in the irqchip core
preventing the systems from entering sleep states like "suspend to RAM".

The GICv1/v2 controllers support wakeup events. They signal these wakeup
events even when CPU interface is disabled which means the wakeup
outputs are always enabled with the required logic in always-on domain.
An implementation can powerdown the GIC completely, but then the wake-up
must be relayed to some control logic within the power controller that
acts as wake-up interrupt controller.

Setting the IRQCHIP_SKIP_SET_WAKE flags will ensure that the interrupts
from GIC can work as wakeup interrupts and resume from suspend-to-{idle,
ram}. The wakeup interrupt sources need to use enable_irq_wake() and the
irqchip core will then set the IRQD_WAKEUP_STATE flag.

Also it's always safer to mask all the non wakeup interrupts are masked
at the chip level when suspending. The irqchip infrastructure can handle
masking of those interrupts at the chip level. The chip implementation
just have to indicate that with IRQCHIP_MASK_ON_SUSPEND.

This patch enables IRQCHIP_SKIP_SET_WAKE and IRQCHIP_MASK_ON_SUSPEND so
that the irqchip core allows and handles the power managemant wake up
modes.
Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Simon Horman <horms@verge.net.au>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Gregory CLEMENT <gregory.clement@free-electrons.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1436971109-20189-1-git-send-email-sudeep.holla@arm.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>