When we don't have the DirectLPI feature, we must work around the
architecture shortcomings to be able to perform the required
maintenance (interrupt masking, clearing and injection).

For this, we create a fake device whose sole purpose is to
provide a way to issue commands as if we were dealing with LPIs
coming from that device (while they actually originate from
the ITS). This fake device doesn't have LPIs allocated to it,
but instead uses the VPE LPIs.

Of course, this could be a real bottleneck, and a naive
implementation would require 6 commands to issue an invalidation.

Instead, let's allocate at least one event per physical CPU
(rounded up to the next power of 2), and opportunistically
map the VPE doorbell to an event. This doorbell will be mapped
until we roll over and need to reallocate this slot.

This ensures that most of the time, we only need 2 commands
to issue an INV, INT or CLEAR, making the performance a lot
better, given that we always issue a CLEAR on entry, and
an INV on each side of a trapped WFI.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

The normal course of action when allocating the ITS' view of a
device is to allocate the corresponding LPIs. But we're about
to introduce devices that borrow their interrupts from
some other entities.

So let's make the allocation optional.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

When masking/unmasking a doorbell interrupt, it is necessary
to issue an invalidation to the corresponding redistributor.
We use the DirectLPI feature by writting directly to the corresponding
redistributor.
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

When we're about to run a vcpu, it is crucial that the redistributor
associated with the physical CPU is being told about the new residency.

This is abstracted by hijacking the irq_set_affinity method for the
doorbell interrupt associated with the VPE. It is expected that the
hypervisor will call this method before scheduling the VPE.
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

When a guest issues a INVALL command targetting a collection, it must
be translated into a VINVALL for the VPE that has this collection.

This patch implements a hook that offers this functionallity to the
hypervisor.
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

When a VPE is scheduled to run, the corresponding redistributor must
be told so, by setting VPROPBASER to the VM's property table, and
VPENDBASER to the vcpu's pending table.

When scheduled out, we preserve the IDAI and PendingLast bits. The
latter is specially important, as it tells the hypervisor that
there are pending interrupts for this vcpu.
Reviewed-by: NEric Auger <eric.auger@redhat.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

On activation, a VPE is mapped using the VMAPP command, followed
by a VINVALL for a good measure. On deactivation, the VPE is
simply unmapped.
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

When creating a VM, the low level GICv4 code is responsible for:
- allocating each VPE a unique VPEID
- allocating a doorbell interrupt for each VPE
- allocating the pending tables for each VPE
- allocating the property table for the VM

This of course has to be reversed when the VM is brought down.

All of this is wired into the irq domain alloc/free methods.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Add the basic GICv4 VPE (vcpu in GICv4 parlance) infrastructure
(irqchip, irq domain) that is going to be populated in the following
patches.
Reviewed-by: NEric Auger <eric.auger@redhat.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

When a VLPI is reconfigured (enabled, disabled, change in priority),
the full configuration byte must be written, and the caches invalidated.

Also, when using the irq_mask/irq_unmask methods, it is necessary
to disable the doorbell for that particular interrupt (by mapping it
to 1023) on top of clearing the Enable bit.
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NEric Auger <eric.auger@redhat.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

In order to let a VLPI being injected into a guest, the VLPI must
be mapped using the VMAPTI command. When moved to a different vcpu,
it must be moved with the VMOVI command.

These commands are issued via the irq_set_vcpu_affinity method,
making sure we unmap the corresponding host LPI first.

The reverse is also done when the VLPI is unmapped from the guest.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Add the skeleton irq_set_vcpu_affinity method that will be used
to configure VLPIs.
Reviewed-by: NEric Auger <eric.auger@redhat.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Add the new GICv4 ITS command definitions, most of them, being
defined in terms of their physical counterparts.
Reviewed-by: NEric Auger <eric.auger@redhat.com>
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

We're are going to need to change a bit more than just the enable
bit in the LPI property table in the future. So let's change the
LPI configuration funtion to take a set of bits to be cleared,
and a set of bits to be set.

This way, we'll be able to use it when a guest updates an LPI
property (priority, for example).
Reviewed-by: NEric Auger <eric.auger@redhat.com>
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

As we want to use 2-level tables for VCPUs, let's hack the device
table allocator in order to make it slightly more generic. It
will get reused in subsequent patches.
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NEric Auger <eric.auger@redhat.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Rework LPI deallocation so that it can be reused by the v4 support
code.
Reviewed-by: NEric Auger <eric.auger@redhat.com>
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Just as for the property table, let's move the pending table
allocation to a separate function.
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NEric Auger <eric.auger@redhat.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

The VCPU tables can be quite sparse as well, and it makes sense
to use indirect tables as well if possible.
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NEric Auger <eric.auger@redhat.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Move the LPI property table allocation into its own function, as
this is going to be required for those associated with VMs in
the future.
Reviewed-by: NEric Auger <eric.auger@redhat.com>
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Allow the pending state of an LPI to be set or cleared via
irq_set_irqchip_state.
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NEric Auger <eric.auger@redhat.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Most ITS commands do operate on a collection object, and require
a SYNC command to be performed on that collection in order to
guarantee the execution of the first command.

With GICv4 ITS, another set of commands perform similar operations
on a VPE object, and a VSYNC operations must be executed to guarantee
their execution.

Given the similarities (post a command, perform a synchronization
operation on a sync object), it makes sense to reuse the same
mechanism for both class of commands.

Let's start with turning its_send_single_command into a huge macro
that performs the bulk of the work, and a set of helpers that
make this macro usable for the GICv3 ITS commands.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Add the probing code for the ITS VLPI support. This includes
configuring the ITS number if not supporting the single VMOVP
command feature.
Reviewed-by: NEric Auger <eric.auger@redhat.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

The various LPI definitions are in the middle of the code, and
would be better placed at the beginning, given that we're going
to use some of them much earlier.
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NEric Auger <eric.auger@redhat.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Now that we have a custom printf format specifier, convert users of
full_name to use %pOF instead. This is preparation to remove storing
of the full path string for each node.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Lee Jones <lee@kernel.org>
Cc: Stefan Wahren <stefan.wahren@i2se.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Ray Jui <rjui@broadcom.com>
Cc: Scott Branden <sbranden@broadcom.com>
Cc: bcm-kernel-feedback-list@broadcom.com
Cc: Sylvain Lemieux <slemieux.tyco@gmail.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: "Sören Brinkmann" <soren.brinkmann@xilinx.com>
Cc: linux-rpi-kernel@lists.infradead.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mediatek@lists.infradead.org
Cc: linux-tegra@vger.kernel.org
Acked-by: NEric Anholt <eric@anholt.net>
Acked-by: NBaruch Siach <baruch@tkos.co.il>
Acked-by: NVladimir Zapolskiy <vz@mleia.com>
Acked-by: NMatthias Brugger <matthias.bgg@gmail.com>
Acked-by: NAlexandre Torgue <alexandre.torgue@st.com>
Acked-by: NMaxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: NRob Herring <robh@kernel.org>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

wait_for_range_completion() is nicely busted when handling
wrapping of the command queue, leading to an early exit
instead of waiting for the command to have been executed.

Fortunately, the impact is pretty minor, as it only impair
the detection of an ITS that doesn't make any forward progress
for a whole second. And an ITS should *never* lock up.
Reported-by: NYang Yingliang <yangyingliang@huawei.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

The current ITS driver is assuming every ITS hardware implementation
supports minimum of 16bit INTID. But this is not true, as per GICv3
specification, INTID field is IMPLEMENTATION DEFINED in the range of
14-24 bits. We might see an unpredictable system behavior on systems
where hardware support less than 16bits and software tries to use
64K LPI interrupts.

On Qualcomm Datacenter Technologies QDF2400 platform, boot log shows
confusing information about number of LPI chunks as shown below. The
QDF2400 ITS hardware supports 24bit INTID.

This patch allocates the memory resources for PEND/PROP tables based
on discoverable value which is specified in GITS_TYPER.IDbits. Also
it fixes the log message that reflects the correct number of LPI
chunks were allocated.

ITS@0xff7efe0000: allocated 524288 Devices @3c0400000 (indirect, esz 8, psz 64K, shr 1)
ITS@0xff7efe0000: allocated 8192 Interrupt Collections @3c0130000 (flat, esz 8, psz 64K, shr 1)
ITS@0xff7efe0000: allocated 8192 Virtual CPUs @3c0140000 (flat, esz 8, psz 64K, shr 1)
ITS: Allocated 524032 chunks for LPIs
PCI/MSI: ITS@0xff7efe0000 domain created
Platform MSI: ITS@0xff7efe0000 domain created
Signed-off-by: NShanker Donthineni <shankerd@codeaurora.org>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Add code to parse SRAT ITS Affinity sub table as defined in ACPI 6.2.
Later in per device probe, ITS devices are mapped to numa node using
ITS Id to proximity domain mapping.

[maz: fix dependency on ACPICA, fixed structure name, minor cleanups]
Reviewed-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: NGanapatrao Kulkarni <ganapatrao.kulkarni@cavium.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

of_device_ids are not supposed to change at runtime. All functions
working with of_device_ids provided by <linux/of.h> work with const
of_device_ids. So mark the non-const structs as const.
Signed-off-by: NArvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Now that we have irq_domain_update_bus_token(), switch everyone over
to it. The debugfs code thanks you for your continued support.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Just skip the irq affinity setting when the target cpu is the same as
current setting.
This is a small optimization for irq affinity setting logic.
Signed-off-by: NMaJun <majun258@huawei.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Rearrange header file includes in alphabetic order.
Signed-off-by: NHanjun Guo <hanjun.guo@linaro.org>
[lorenzo.pieralisi@arm.com: fixed commit log]
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: NMing Lei <ming.lei@canonical.com>
Tested-by: NWei Xu <xuwei5@hisilicon.com>
Tested-by: NSinan Kaya <okaya@codeaurora.org>
Cc: Tomasz Nowicki <tn@semihalf.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

On Qualcomm Datacenter Technologies QDF2400 SoCs, the ITS hardware
implementation uses 16Bytes for Interrupt Translation Entry (ITE),
but reports an incorrect value of 8Bytes in GITS_TYPER.ITTE_size.

It might cause kernel memory corruption depending on the number
of MSI(x) that are configured and the amount of memory that has
been allocated for ITEs in its_create_device().

This patch fixes the potential memory corruption by setting the
correct ITE size to 16Bytes.

Cc: stable@vger.kernel.org
Signed-off-by: NShanker Donthineni <shankerd@codeaurora.org>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

When reusing commands from the ring buffer, it would be better
to zero them out, even if the ITS should ignore the unused
fields.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

The its command buffer must be page aligned, but kzalloc() is not
guaranteed to be (though it is mostly when allocating 64k). Use
__get_free_pages() as this is used for other buffers as well.
Signed-off-by: NRobert Richter <rrichter@cavium.com>
[Marc: fixed the error path]
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Back in the days when the GICv3/v4 architecture was drafted,
the command to an event to an LPI number was called MAPVI.
Later on, and to avoid confusion with the GICv4 command VMAPI,
it was renamed MAPTI. We've carried the old name for a long
time, but it gets in the way of people reading the code in
the light of the public architecture specification.

Just repaint all the references and kill the old definition.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

During the development of the GICv3/v4 architecture, it was
envisaged to have a CPU table, though the use for it was
never completely clear (the collection table serves that role
pretty well). It ended being dropped before the specification
was published, though it lived on in the driver.

In order to avoid people scratching their head too much, let's do
the same in the kernel.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

The way we encode the various ITS command fields is both tedious
and error prone. Let's introduce a helper function that performs
the encoding, and convert the existing encoders to use that
helper. It also has the advantage of expressing the encoding in
a way that matches the architecture specification.
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

Read-allocation hints are not enabled for both the GIC-ITS and GICR
tables. This forces the hardware to always read the table contents
from an external memory (DDR) which is slow compared to cache memory.
Most of the tables are often read by hardware. So, it's better to
enable Read-allocate hints in addition to Write-allocate hints in
order to improve the GICR_PEND, GICR_PROP, Collection, Device, and
vCPU tables lookup time.
Signed-off-by: NShanker Donthineni <shankerd@codeaurora.org>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>

The GICv3 ITS is MSI remapping capable. Let's advertise
this property so that VFIO passthrough can assess IRQ safety.
Signed-off-by: NEric Auger <eric.auger@redhat.com>
Reviewed-by: NMarc Zyngier <marc.zyngier@arm.com>
Reviewed-by: NTomasz Nowicki <tomasz.nowicki@caviumnetworks.com>
Tested-by: NTomasz Nowicki <tomasz.nowicki@caviumnetworks.com>
Tested-by: NBharat Bhushan <bharat.bhushan@nxp.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

readq and writeq type of assessors are not supported in AArch32, so we
need to specialise them and glue later with series of 32-bit accesses
on AArch32 side.
Signed-off-by: NVladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>