linux-stable.git/kernel/irq/chip.c, branch v5.2

genirq: Introduce irq_chip_{request,release}_resource_parent() apis

2019-05-01T09:41:38+00:00

Introduce irq_chip_{request,release}_resource_parent() apis so
that these can be used in hierarchical irqchips.

Signed-off-by: Lokesh Vutla 
Signed-off-by: Marc Zyngier

genirq: Respect IRQCHIP_SKIP_SET_WAKE in irq_chip_set_wake_parent()

2019-04-05T15:41:41+00:00

If a child irqchip calls irq_chip_set_wake_parent() but its parent irqchip
has the IRQCHIP_SKIP_SET_WAKE flag set an error is returned.

This is inconsistent behaviour vs. set_irq_wake_real() which returns 0 when
the irqchip has the IRQCHIP_SKIP_SET_WAKE flag set. It doesn't attempt to
walk the chain of parents and set irq wake on any chips that don't have the
flag set either. If the intent is to call the .irq_set_wake() callback of
the parent irqchip, then we expect irqchip implementations to omit the
IRQCHIP_SKIP_SET_WAKE flag and implement an .irq_set_wake() function that
calls irq_chip_set_wake_parent().

The problem has been observed on a Qualcomm sdm845 device where set wake
fails on any GPIO interrupts after applying work in progress wakeup irq
patches to the GPIO driver. The chain of chips looks like this:

     QCOM GPIO -> QCOM PDC (SKIP) -> ARM GIC (SKIP)

The GPIO controllers parent is the QCOM PDC irqchip which in turn has ARM
GIC as parent.  The QCOM PDC irqchip has the IRQCHIP_SKIP_SET_WAKE flag
set, and so does the grandparent ARM GIC.

The GPIO driver doesn't know if the parent needs to set wake or not, so it
unconditionally calls irq_chip_set_wake_parent() causing this function to
return a failure because the parent irqchip (PDC) doesn't have the
.irq_set_wake() callback set. Returning 0 instead makes everything work and
irqs from the GPIO controller can be configured for wakeup.

Make it consistent by returning 0 (success) from irq_chip_set_wake_parent()
when a parent chip has IRQCHIP_SKIP_SET_WAKE set.

[ tglx: Massaged changelog ]

Fixes: 08b55e2a9208e ("genirq: Add irqchip_set_wake_parent")
Signed-off-by: Stephen Boyd 
Signed-off-by: Thomas Gleixner 
Acked-by: Marc Zyngier 
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-gpio@vger.kernel.org
Cc: Lina Iyer 
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20190325181026.247796-1-swboyd@chromium.org

Merge tag 'gpio-v5.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

2019-03-08T18:09:53+00:00

Pull GPIO updates from Linus Walleij:
"This is the bulk of GPIO changes for the v5.1 cycle:

Core changes:

- The big change this time around is the irqchip handling in the
qualcomm pin controllers, closely coupled with the gpiochip. This
rework, in a classic fall-between-the-chairs fashion has been
sidestepped for too long.

The Qualcomm IRQchips using the SPMI and SSBI transport mechanisms
have been rewritten to use hierarchical irqchip. This creates the
base from which I intend to gradually pull support for hierarchical
irqchips into the gpiolib irqchip helpers to cut down on duplicate
code.

We have too many hacks in the kernel because people have been
working around the missing hierarchical irqchip for years, and once
it was there, noone understood it for a while. We are now slowly
adapting to using it.

This is why this pull requests include changes to MFD, SPMI,
IRQchip core and some ARM Device Trees pertaining to the Qualcomm
chip family. Since Qualcomm have so many chips and such large
deployments it is paramount that this platform gets this right, and
now it (hopefully) does.

- Core support for pull-up and pull-down configuration, also from the
device tree. When a simple GPIO chip supports an "off or on" pull-up
or pull-down resistor, we provide a way to set this up using
machine descriptors or device tree.

If more elaborate control of pull up/down (such as resistance shunt
setting) is required, drivers should be phased over to use pin
control. We do not yet provide a userspace ABI for this pull
up-down setting but I suspect the makers are going to ask for it
soon enough. PCA953x is the first user of this new API.

- The GPIO mockup driver has been revamped after some discussion
improving the IRQ simulator in the process.

The idea is to make it possible to use the mockup for both testing
and virtual prototyping, e.g. when you do not yet have a GPIO
expander to play with but really want to get something to develop
code around before hardware is available. It's neat. The blackbox
testing usecase is currently making its way into kernelci.

- ACPI GPIO core preserves non direction flags when updating flags.

- A new device core helper for devm_platform_ioremap_resource() is
funneled through the GPIO tree with Greg's ACK.

New drivers:

- TQ-Systems QTMX86 GPIO controllers (using port-mapped I/O)

- Gateworks PLD GPIO driver (vaccumed up from OpenWrt)

- AMD G-Series PCH (Platform Controller Hub) GPIO driver.

- Fintek F81804 & F81966 subvariants.

- PCA953x now supports NXP PCAL6416.

Driver improvements:

- IRQ support on the Nintendo Wii (Hollywood) GPIO.

- get_direction() support for the MVEBU driver.

- Set the right output level on SAMA5D2.

- Drop the unused irq trigger setting on the Spreadtrum driver.

- Wakeup support for PCA953x.

- A slew of cleanups in the various Intel drivers"

* tag 'gpio-v5.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (110 commits)
gpio: gpio-omap: fix level interrupt idling
gpio: amd-fch: Set proper output level for direction_output
x86: apuv2: remove unused variable
gpio: pca953x: Use PCA_LATCH_INT
platform/x86: fix PCENGINES_APU2 Kconfig warning
gpio: pca953x: Fix dereference of irq data in shutdown
gpio: amd-fch: Fix type error found by sparse
gpio: amd-fch: Drop const from resource
gpio: mxc: add check to return defer probe if clock tree NOT ready
gpio: ftgpio: Register per-instance irqchip
gpio: ixp4xx: Add DT bindings
x86: pcengines apuv2 gpio/leds/keys platform driver
gpio: AMD G-Series PCH gpio driver
drivers: depend on HAS_IOMEM for devm_platform_ioremap_resource()
gpio: tqmx86: Set proper output level for direction_output
gpio: sprd: Change to use SoC compatible string
gpio: sprd: Use SoC compatible string instead of wildcard string
gpio: of: Handle both enable-gpio{,s}
gpio: of: Restrict enable-gpio quirk to regulator-gpio
gpio: davinci: use devm_platform_ioremap_resource()
...

Merge tag 'irqchip-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core

2019-02-23T09:53:31+00:00

Pull irqchip updates from Marc Zyngier

- Core pseudo-NMI handling code
- Allow the default irq domain to be retrieved
- A new interrupt controller for the Loongson LS1X platform
- Affinity support for the SiFive PLIC
- Better support for the iMX irqsteer driver
- NUMA aware memory allocations for GICv3
- A handful of other fixes (i8259, GICv3, PLIC)

Merge branch 'ib-qcom-ssbi' into devel

2019-02-21T11:58:31+00:00

genirq: introduce irq_chip_mask_ack_parent()

2019-02-13T08:23:05+00:00

The hierarchical irqchip never before ran into a situation
where the parent is not "simple", i.e. does not implement
.irq_ack() and .irq_mask() like most, but the qcom-pm8xxx.c
happens to implement only .irq_mask_ack().

Since we want to make ssbi-gpio a hierarchical child of this
irqchip, it must *also* only implement .irq_mask_ack()
and call down to the parent, and for this we of course
need irq_chip_mask_ack_parent().

Cc: Marc Zyngier 
Cc: Thomas Gleixner 
Acked-by: Marc Zyngier 
Signed-off-by: Brian Masney 
Signed-off-by: Linus Walleij

genirq: Avoid summation loops for /proc/stat

2019-02-10T20:34:45+00:00

Waiman reported that on large systems with a large amount of interrupts the
readout of /proc/stat takes a long time to sum up the interrupt
statistics. In principle this is not a problem. but for unknown reasons
some enterprise quality software reads /proc/stat with a high frequency.

The reason for this is that interrupt statistics are accounted per cpu. So
the /proc/stat logic has to sum up the interrupt stats for each interrupt.

This can be largely avoided for interrupts which are not marked as
'PER_CPU' interrupts by simply adding a per interrupt summation counter
which is incremented along with the per interrupt per cpu counter.

The PER_CPU interrupts need to avoid that and use only per cpu accounting
because they share the interrupt number and the interrupt descriptor and
concurrent updates would conflict or require unwanted synchronization.

Reported-by: Waiman Long 
Signed-off-by: Thomas Gleixner 
Reviewed-by: Waiman Long 
Reviewed-by: Marc Zyngier 
Reviewed-by: Davidlohr Bueso 
Cc: Matthew Wilcox 
Cc: Andrew Morton 
Cc: Alexey Dobriyan 
Cc: Kees Cook 
Cc: linux-fsdevel@vger.kernel.org
Cc: Davidlohr Bueso 
Cc: Miklos Szeredi 
Cc: Daniel Colascione 
Cc: Dave Chinner 
Cc: Randy Dunlap 
Link: https://lkml.kernel.org/r/20190208135020.925487496@linutronix.de


8<-------------

v2: Undo the unintentional layout change of struct irq_desc.

 include/linux/irqdesc.h |    1 +
 kernel/irq/chip.c       |   12 ++++++++++--
 kernel/irq/internals.h  |    8 +++++++-
 kernel/irq/irqdesc.c    |    7 ++++++-
 4 files changed, 24 insertions(+), 4 deletions(-)

genirq: Provide NMI handlers

2019-02-05T14:37:01+00:00

Provide flow handlers that are NMI safe for interrupts and percpu_devid
interrupts.

Signed-off-by: Julien Thierry 
Acked-by: Marc Zyngier 
Cc: Thomas Gleixner 
Cc: Marc Zyngier 
Cc: Peter Zijlstra 
Signed-off-by: Marc Zyngier

genirq: export irq_chip_set_wake_parent symbol

2019-02-04T10:02:51+00:00

Export the irq_chip_set_wake_parent symbol so that drivers with
hierarchical IRQ chips can be built as a module.

Signed-off-by: Brian Masney 
Reported-by: Mark Brown 
Acked-by: Marc Zyngier 
Signed-off-by: Linus Walleij

genirq: Fix various typos in comments

2018-12-18T13:22:28+00:00

Go over the IRQ subsystem source code (including irqchip drivers) and
fix common typos in comments.

No change in functionality intended.

Signed-off-by: Ingo Molnar 
Cc: Thomas Gleixner 
Cc: Jason Cooper 
Cc: Marc Zyngier 
Cc: Peter Zijlstra 
Cc: Linus Torvalds 
Cc: linux-kernel@vger.kernel.org