The GICv3 ITS doesn't really depend on PCI. Only the PCI/MSI
part of it does, and there is no reason not to blow away most
of the irqchip stack because PCI is not selected (though not
selecting PCI seem to be asking for punishment, but hey...).

So let's split the PCI-specific part from the ITS in the Kconfig
file, and let's make that part depend on PCI. Architecture specific
hacks (arch/arm{,64}/Kconfig) will be addressed in a separate patch.
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

In some randconfig scenarios, including arm-gic-v4.h results
in a spurious wawrning about the $SUBJECT structure not being
defined. Adding a forward definition keeps it quiet.
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

pr_err() messages should end with a new-line to avoid other messages
being concatenated.
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

pr_err() messages should end with a new-line to avoid other messages
being concatenated.
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

Fix child-node lookup during initialisation, which ended up searching
the whole device tree depth-first starting at the parent rather than
just matching on its children.

To make things worse, the parent gic node was prematurely freed, while
the ppi-partitions node was leaked.

Fixes: e3825ba1 ("irqchip/gic-v3: Add support for partitioned PPIs")
Cc: stable <stable@vger.kernel.org>     # 4.7
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

Should the call to irq_set_vcpu_affinity() fail at map time,
we should restore the normal lazy-disable behaviour instead
of staying with the eager disable that GICv4 requires.
Reported-by: Eric Auger <eric.auger@redhat.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

When requesting a shared interrupt, we assume that the firmware
support code (DT or ACPI) has called irqd_set_trigger_type
already, so that we can retrieve it and check that the requester
is being reasonnable.

Unfortunately, we still have non-DT, non-ACPI systems around,
and these guys won't call irqd_set_trigger_type before requesting
the interrupt. The consequence is that we fail the request that
would have worked before.

We can either chase all these use cases (boring), or address it
in core code (easier). Let's have a per-irq_desc flag that
indicates whether irqd_set_trigger_type has been called, and
let's just check it when checking for a shared interrupt.
If it hasn't been set, just take whatever the interrupt
requester asks.

Fixes: 382bd4de ("genirq: Use irqd_get_trigger_type to compare the trigger type for shared IRQs")
Cc: stable@vger.kernel.org
Reported-and-tested-by: Petr Cvek <petrcvekcz@gmail.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

If the physical address of the GIC resource cannot be read from device
tree, then the code falls back to reading it from the gcr_gic_base
register. Hopefully this has been set to a sane value by the bootloader
or some platform code, but is defined by the hardware manual to have
"undefined" reset state. Using it as the address at which the GIC will
be mapped into physical memory space can therefore be risky if it has
not been initialised, since it may result in the GIC being mapped to an
effectively random address anywhere in physical memory, where it might
conflict with peripherals or RAM and lead to weird crashes.

Since a "sane value" is very platform specific because it is particular
to the platform's memory map, it is difficult to test for. At the very
least, a warning message should be printed in the case that we trust the
inherited value.
Reported-by: Amit Kama <amit.kama@satixfy.com>
Signed-off-by: Matt Redfearn <matt.redfearn@mips.com>
Reviewed-by: Paul Burton <paul.burton@mips.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

Several messages from the MIPS GIC driver include the text "GIC", but
the format is not standard. Add a pr_fmt of "irq-mips-gic: " and reword
the messages now that they will be prefixed with the driver name.
Signed-off-by: Matt Redfearn <matt.redfearn@mips.com>
Reviewed-by: Paul Burton <paul.burton@mips.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

Move irq_set_wake on interrupt mask, needed to wake up from
low power mode as the event mask is not able to do so.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

-After cold boot, imr default value depends on hardware configuration.
-After hot reboot the registers must be cleared to avoid residue.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

stm32h7 has up to 96 inputs
(3 banks of 32 inputs max).
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

This patch updates stm32-exti documentation with stm32h7-exti
compatible string.
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

-Prepare to manage multi-bank of external interrupts
(N banks of 32 inputs).
-Prepare to manage registers offsets by compatible
(registers offsets could be different follow per stm32 platform).
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

This patch adds GENERIC_IRQ_CHIP to stm32 exti
config.
Signed-off-by: Ludovic Barre <ludovic.barre@st.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

The Socionext Synquacer SoC has an external interrupt unit (EXIU)
that forwards a block of 32 configurable input lines to 32 adjacent
level-high type GICv3 SPIs.

The EXIU has per-interrupt level/edge and polarity controls, and
mask bits that keep the outgoing lines de-asserted, even though
the controller may still latch interrupt conditions that occur
while the line is masked.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

Add a description of the External Interrupt Unit (EXIU) interrupt
controller as found on the Socionext SynQuacer SoC.
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

its_vpe_irq_domain_activate should always return 0. Really. There
is not a single case why it wouldn't.  So this "return true;" is
really a copy/paste issue that got revealed now that we actually
check the return value of the activate method.

Brown paper bag day.

Fixes: 2247e1bf ("irqchip/gic-v3-its: Limit scope of VPE mapping to be per ITS")
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

We have 2 bitmaps used to keep track of interrupts dedicated to IPIs in
the MIPS GIC irqchip driver. These bitmaps are only used from the one
compilation unit of that driver, and so can be made static. Do so in
order to avoid polluting the symbol table & global namespace.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

The gic_set_type() function included writes to the MIPS GIC polarity,
trigger & dual-trigger registers in each case of a switch statement
determining the IRQs type. This is all well & good when we only have a
single cluster & thus a single GIC whose register we want to update. It
will lead to significant duplication once we have multi-cluster support
& multiple GICs to update.

Refactor this such that we determine values for the polarity, trigger &
dual-trigger registers and then have a single set of register writes
following the switch statement. This will allow us to write the same
values to each GIC in a multi-cluster system in a later patch, rather
than needing to duplicate more register writes in each case.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

Following the past few patches nothing uses the gic_vpes variable any
longer. Remove the dead code.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

Reserving a number of IPIs based upon the number of VPs reported by the
GIC makes little sense for a few reasons:

 - The kernel may have been configured with NR_CPUS less than the number
   of VPs in the cluster, in which case using gic_vpes causes us to
   reserve more interrupts for IPIs than we will possibly use.

 - If a kernel is configured without support for multi-threading & runs
   on a system with multi-threading & multiple VPs per core then we'll
   similarly reserve more interrupts for IPIs than we will possibly use.

 - In systems with multiple clusters the GIC can only provide us with
   the number of VPs in its cluster, not across all clusters. In this
   case we'll reserve fewer interrupts for IPIs than we need.

Fix these issues by using num_possible_cpus() instead, which in all
cases is actually indicative of how many IPIs we may need.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

Rather than configuring EIC mode for all CPUs during boot, configure it
locally on each when they come online. This will become important with
multi-cluster support, since clusters may be powered on & off (for
example via hotplug) and would lose the EIC configuration when powered
off.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

We currently walk through the range 0..gic_vpes-1, expecting these
values all to be valid Linux CPU numbers to provide to mips_cm_vp_id(),
and masking all routable local interrupts during boot. This approach has
a few drawbacks:

 - In multi-cluster systems we won't have access to all CPU's GIC local
   registers when the driver is probed, since clusters (and their GICs)
   may be powered down at this point & only brought online later.

 - In multi-cluster systems we may power down clusters at runtime, for
   example if we offline all CPUs within it via hotplug, and the
   cluster's GIC may lose state. We therefore need to reinitialise it
   when powering back up, which this approach does not take into
   account.

 - The range 0..gic_vpes-1 may not all be valid Linux CPU numbers, for
   example if we run a kernel configured to support fewer CPUs than the
   system it is running on actually has. In this case we'll get garbage
   values from mips_cm_vp_id() as we read past the end of the cpu_data
   array.

Fix this and simplify the code somewhat by writing an all-bits-set
value to the VP-local reset mask register when a CPU is brought online,
before any local interrupts are configured for it. This removes the need
for us to access all CPUs during driver probe, removing all of the
problems described above.

In the name of simplicity we drop the checks for routability of
interrupts and simply clear the mask bits for all interrupts. Bits for
non-routable local interrupts will have no effect so there's no point
performing extra work to avoid modifying them.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

The gic_all_vpes_local_irq_controller chip currently attempts to operate
on all CPUs/VPs in the system when masking or unmasking an interrupt.
This has a few drawbacks:

 - In multi-cluster systems we may not always have access to all CPUs in
   the system. When all CPUs in a cluster are powered down that
   cluster's GIC may also power down, in which case we cannot configure
   its state.

 - Relatedly, if we power down a cluster after having configured
   interrupts for CPUs within it then the cluster's GIC may lose state &
   we need to reconfigure it. The current approach doesn't take this
   into account.

 - It's wasteful if we run Linux on fewer VPs than are present in the
   system. For example if we run a uniprocessor kernel on CPU0 of a
   system with 16 CPUs then there's no point in us configuring CPUs
   1-15.

 - The implementation is also lacking in that it expects the range
   0..gic_vpes-1 to represent valid Linux CPU numbers which may not
   always be the case - for example if we run on a system with more VPs
   than the kernel is configured to support.

Fix all of these issues by only configuring the affected interrupts for
CPUs which are online at the time, and recording the configuration in a
new struct gic_all_vpes_chip_data for later use by CPUs being brought
online. We register a CPU hotplug state (reusing
CPUHP_AP_IRQ_GIC_STARTING which the ARM GIC driver uses, and which seems
suitably generic for reuse with the MIPS GIC) and execute
irq_cpu_online() in order to configure the interrupts on the newly
onlined CPU.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

The gic_local_irq_domain_map() function has only one callsite in
gic_irq_domain_map(), and the split between the two functions makes it
unclear that they duplicate calculations & checks.

Inline gic_local_irq_domain_map() into gic_irq_domain_map() in order to
clean this up. Doing this makes the following small issues obvious, and
the patch tidies them up:

 - Both functions used GIC_HWIRQ_TO_LOCAL() to convert a hwirq number to
   a local IRQ number. We now only do this once. Although the compiler
   ought to have optimised this away before anyway, the change leaves us
   with less duplicate code.

 - gic_local_irq_domain_map() had a check for invalid local interrupt
   numbers (intr > GIC_LOCAL_INT_FDC). This condition can never occur
   because any hwirq higher than those used for local interrupts is a
   shared interrupt, which gic_irq_domain_map() already handles
   separately. We therefore remove this check.

 - The decision of whether to map the interrupt to gic_cpu_pin or
   timer_cpu_pin can be handled within the existing switch statement in
   gic_irq_domain_map(), shortening the code a little.

The change additionally prepares us nicely for the following patch of
the series which would otherwise need to duplicate the check for whether
a local interrupt should be percpu_devid or just percpu (ie. the switch
statement from gic_irq_domain_map()) in gic_local_irq_domain_map().
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

Meson8 uses the same GPIO interrupt controller IP block as the other
Meson SoCs. A total of 134 pins can be spied on, which is the sum of:
- 22 pins on bank GPIOX
- 17 pins on bank GPIOY
- 30 pins on bank GPIODV
- 10 pins on bank GPIOH
- 15 pins on bank GPIOZ
- 7 pins on bank CARD
- 19 pins on bank BOOT
- 14 pins in the AO domain
Acked-by: Kevin Hilman <khilman@baylibre.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

Commit:

f110711a ("irqdomain: Convert irqdomain-%3Eof_node to fwnode")

converted of_node field to fwnode, but didn't update its comments.

Update it.

Fixes: f110711a ("irqdomain: Convert irqdomain-%3Eof_node to fwnode")
Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

There is a lot of broken firmware out there that don't really
expose the information the kernel requires when it comes with dealing
with GICv2:

(1) Firmware that only describes the first 4kB of GICv2
(2) Firmware that describe 128kB of CPU interface, while
    the usable portion of the address space is between
    60 and 68kB

So far, we only deal with (2). But we have platforms exhibiting
behaviour (1), resulting in two sub-cases:
(a) The GIC is occupying 8kB, as required by the GICv2 architecture
(b) It is actually spread 128kB, and this is likely to be a version
    of (2)

This patch tries to work around both (a) and (b) by poking at
the outside of the described memory region, and try to work out
what is actually there. This is of course unsafe, and should
only be enabled if there is no way to otherwise fix the DT provided
by the firmware (we provide a "irqchip.gicv2_force_probe" option
to that effect).

Note that for the time being, we restrict ourselves to GICv2
implementations provided by ARM, since there I have no knowledge
of an alternative implementations. This could be relaxed if such
an implementation comes to light on a broken platform.
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

So far, we require the hypervisor to update the VLPI properties
once the the VLPI mapping has been established. While this
makes it easy for the ITS driver, it creates a window where
an incoming interrupt can be delivered with an unknown set
of properties. Not very nice.

Instead, let's add a "properties" field to the mapping structure,
and use that to configure the VLPI before it actually gets mapped.
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

Required merge to get mainline irqchip updates.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

In case of error, the function of_iomap() returns NULL pointer not
ERR_PTR(). The IS_ERR() test in the return value check should be
replaced with NULL test..
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

Add support for the interrupt gpio controller found on Amlogic's meson
SoC family.

This controller is a separate controller from the gpio controller. It is
able to spy on the SoC pad. It is essentially a 256 to 8 router with a
filtering block to select level or edge and polarity. The number of actual
mappable inputs depends on the SoC.

Cc: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

This commit adds the device tree bindings description for Amlogic's GPIO
interrupt controller available on the meson8b, gxbb and gxl SoC families

Cc: Heiner Kallweit <hkallweit1@gmail.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

When setting the affinity of a VPE (either because we map or move
it), make sure the effective affinity is correctly reported back
to the core kernel.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

Sending VINVALL to all ITSs is completely pointless, as all
we're trying to achieve is to tell the redistributor that
the property table for this VPE should be invalidated.

Let's issue the command on the first valid ITS and be done with it.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

So far, we map all VPEs on all ITSs. While this is not wrong,
this is quite a big hammer, as moving a VPE around requires
all ITSs to be synchronized. Needles to say, this is an
expensive proposition.

Instead, let's switch to a mode where we issue VMAPP commands
only on ITSs that are actually involved in reporting interrupts
to the given VM.

For that purpose, we refcount the number of interrupts are are
mapped for this VM on each ITS, performing the map/unmap
operations as required. It then allows us to use this refcount
to only issue VMOVP to the ITSs that need to know about this
VM.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

Currently, its_send_vmapp operates on all ITSs. As we're about
to try and limit the amount of commands we send to ITSs that are
not involved in dealing with a given VM, let's redefine that
primitive so that it takes a target ITS as a parameter.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

Currently, its_send_vinvall operates on all ITSs. As we're about
to try and limit the amount of commands we send to ITSs that are
not involved in dealing with a given VM, let's redefine that
primitive so that it takes a target ITS as a parameter.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

As we're about to make use of the maximum number of ITSs in
a GICv4 system, let's make this value global (and rename it to
GICv4_ITS_LIST_MAX).
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>