Commit Graph

29 Commits

Author SHA1 Message Date
Geert Uytterhoeven
ec93b94ac1 irqchip/renesas-intc-irqpin: Use proper irq_chip name and parent
The irq_chip .name field should contain the device's class (not
instance) name, while .parent_device should point to the device itself.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-06-11 12:22:42 +01:00
Geert Uytterhoeven
89626d4bad irqchip/renesas-intc-irqpin: Remove devm_kzalloc() error printing
There is no need to print a message if devm_kzalloc() fails, as the
memory allocation core already takes care of that.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-04-29 16:29:59 +01:00
Kuninori Morimoto
bf9732857b irqchip/irq-renesas-intc-irqpin: Convert to SPDX identifiers
This patch updates license to use SPDX-License-Identifier
instead of verbose license text.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-12-13 09:35:46 +00:00
Geert Uytterhoeven
66bf8252cf irqchip/renesas-intc-irqpin: Use wakeup_path i.s.o. explicit clock handling
Since commit 705bc96c2c ("irqchip: renesas-intc-irqpin: Add
minimal runtime PM support"), when an IRQ is used for wakeup, the INTC
block's module clock (if exists) is manually kept running during system
suspend, to make sure the device stays active.

However, this explicit clock handling is merely a workaround for a
failure to properly communicate wakeup information to the device core.

Instead, set the device's power.wakeup_path field, to indicate this
device is part of the wakeup path.  Depending on the PM Domain's
active_wakeup configuration, the genpd core code will keep the device
enabled (and the clock running) during system suspend when needed.
This allows for the removal of all explicit clock handling code from the
driver.

Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-14 11:11:15 +00:00
Andrew Lunn
39c3fd5895 kernel/irq: Extend lockdep class for request mutex
The IRQ code already has support for lockdep class for the lock mutex
in an interrupt descriptor. Extend this to add a second class for the
request mutex in the descriptor. Not having a class is resulting in
false positive splats in some code paths.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: linus.walleij@linaro.org
Cc: grygorii.strashko@ti.com
Cc: f.fainelli@gmail.com
Link: https://lkml.kernel.org/r/1512234664-21555-1-git-send-email-andrew@lunn.ch
2017-12-28 12:26:35 +01:00
Geert Uytterhoeven
42a5968c0a irqchip/renesas-intc-irqpin: Use of_device_get_match_data() helper
Use the of_device_get_match_data() helper instead of open coding.

Acked-by: Simon Horman <horms+renesas@verge.net.au>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-10-19 10:55:16 +01:00
Geert Uytterhoeven
86e57ca735 irqchip/renesas-intc-irqpin: Improve clock error handling and reporting
If the Renesas External IRQ Pin driver cannot find a functional clock,
it prints a warning, .e.g.

    renesas_intc_irqpin fe78001c.interrupt-controller: unable to get clock

and continues, as the clock is optional, depending on the SoC type.
This warning may confuse users.

To fix this, add a flag to indicate that the clock is mandatory or
optional, and add a few more compatible entries:
  - If the clock is mandatory (on R-Mobile A1 or SH-Mobile AG5), a
    missing clock is now treated as a fatal error,
  - If the clock is optional (on R-Car Gen1, or using the generic
    "renesas,intc-irqpin" compatible value), the warning is no longer
    printed.

This requires making struct intc_irqpin_irlm_config more generic by
renaming it to intc_irqpin_config, and adding a flag to indicate if IRLM
is needed.
The new clock flag is merged with the existing shared_irqs boolean into
a bitfield to save space.

Suggested-by: Magnus Damm <magnus.damm@gmail.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lkml.kernel.org/r/1448377693-19597-1-git-send-email-geert+renesas@glider.be
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2015-11-24 16:54:19 +00:00
Geert Uytterhoeven
1affe5946f irqchip/renesas-intc-irqpin: Remove intc_irqpin_priv.number_of_irqs
intc_irqpin_priv.number_of_irqs is used inside intc_irqpin_probe() only,
so it can just become a local variable.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1448376581-9202-3-git-send-email-geert+renesas@glider.be
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2015-11-24 16:53:13 +00:00
Geert Uytterhoeven
f9551a9c08 irqchip/renesas-intc-irqpin: Remove obsolete platform data support
Since commit 4baadb9e05 ("ARM: shmobile: r8a7778: remove obsolete
setup code"), all Renesas SoCs with a renesas-intc-irqpin module are
only supported in generic DT-only ARM multi-platform builds.  The driver
doesn't need to use platform data anymore, hence remove platform data
configuration.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1448376581-9202-2-git-send-email-geert+renesas@glider.be
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2015-11-24 16:53:00 +00:00
Ulrich Hecht
26c21dd988 irqchip/renesas-intc-irqpin: r8a7778 IRLM setup support
Works the same as on r8a7779.

Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Link: http://lkml.kernel.org/r/1443607387-19147-1-git-send-email-geert+Brenesas@glider.be
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-09-30 21:02:22 +02:00
Rob Herring
d17cab4451 irqchip: Kill off set_irq_flags usage
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: Rob 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.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-09-16 16:53:38 +02:00
Geert Uytterhoeven
f4e209cdc7 irqchip/renesas-intc-irqpin: Propagate wake-up settings to parent
The renesas-intc-irqpin interrupt controller is cascaded to the GIC, but
its driver doesn't propagate wake-up settings to the parent interrupt
controller.

Since commit aec89ef72b ("irqchip/gic: Enable SKIP_SET_WAKE and
MASK_ON_SUSPEND"), the GIC driver masks interrupts during suspend, and
wake-up through gpio-keys now fails on r8a7740/armadillo and
sh73a0/kzm9g.

Fix this by propagating wake-up settings to the parent interrupt
controller. There's no need to handle irq_set_irq_wake() failures, as
the renesas-intc-irqpin interrupt controller is always cascaded to a
GIC, and the GIC driver always sets SKIP_SET_WAKE since the
aforementioned commit.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Link: http://lkml.kernel.org/r/1441731636-17610-2-git-send-email-geert%2Brenesas@glider.be
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-09-15 17:06:29 +02:00
Geert Uytterhoeven
769b5cf78e irqchip/renesas-intc-irqpin: Use a separate lockdep class
The renesas-intc-irqpin interrupt controller is cascaded to the GIC.
Hence when propagating wake-up settings to its parent interrupt
controller, the following lockdep warning is printed:

    =============================================
    [ INFO: possible recursive locking detected ]
    4.2.0-armadillo-10725-g50fcd7643c034198 #781 Not tainted
    ---------------------------------------------
    s2ram/1179 is trying to acquire lock:
    (&irq_desc_lock_class){-.-...}, at: [<c005bb54>] __irq_get_desc_lock+0x78/0x94

    but task is already holding lock:
    (&irq_desc_lock_class){-.-...}, at: [<c005bb54>] __irq_get_desc_lock+0x78/0x94

    other info that might help us debug this:
    Possible unsafe locking scenario:

	  CPU0
	  ----
     lock(&irq_desc_lock_class);
     lock(&irq_desc_lock_class);

    *** DEADLOCK ***

    May be due to missing lock nesting notation

    7 locks held by s2ram/1179:
    #0:  (sb_writers#7){.+.+.+}, at: [<c00c9708>] __sb_start_write+0x64/0xb8
    #1:  (&of->mutex){+.+.+.}, at: [<c0125a00>] kernfs_fop_write+0x78/0x1a0
    #2:  (s_active#23){.+.+.+}, at: [<c0125a08>] kernfs_fop_write+0x80/0x1a0
    #3:  (autosleep_lock){+.+.+.}, at: [<c0058244>] pm_autosleep_lock+0x18/0x20
    #4:  (pm_mutex){+.+.+.}, at: [<c0057e50>] pm_suspend+0x54/0x248
    #5:  (&dev->mutex){......}, at: [<c0243a20>] __device_suspend+0xdc/0x240
    #6:  (&irq_desc_lock_class){-.-...}, at: [<c005bb54>] __irq_get_desc_lock+0x78/0x94

    stack backtrace:
    CPU: 0 PID: 1179 Comm: s2ram Not tainted 4.2.0-armadillo-10725-g50fcd7643c034198

    Hardware name: Generic R8A7740 (Flattened Device Tree)
    [<c00129f4>] (dump_backtrace) from [<c0012bec>] (show_stack+0x18/0x1c)
    [<c0012bd4>] (show_stack) from [<c03f5d94>] (dump_stack+0x20/0x28)
    [<c03f5d74>] (dump_stack) from [<c00514d4>] (__lock_acquire+0x67c/0x1b88)
    [<c0050e58>] (__lock_acquire) from [<c0052df8>] (lock_acquire+0x9c/0xbc)
    [<c0052d5c>] (lock_acquire) from [<c03fb068>] (_raw_spin_lock_irqsave+0x44/0x58)
    [<c03fb024>] (_raw_spin_lock_irqsave) from [<c005bb54>] (__irq_get_desc_lock+0x78/0x94
    [<c005badc>] (__irq_get_desc_lock) from [<c005c3d8>] (irq_set_irq_wake+0x28/0x100)
    [<c005c3b0>] (irq_set_irq_wake) from [<c01e50d0>] (intc_irqpin_irq_set_wake+0x24/0x4c)
    [<c01e50ac>] (intc_irqpin_irq_set_wake) from [<c005c17c>] (set_irq_wake_real+0x3c/0x50
    [<c005c140>] (set_irq_wake_real) from [<c005c414>] (irq_set_irq_wake+0x64/0x100)
    [<c005c3b0>] (irq_set_irq_wake) from [<c02a19b4>] (gpio_keys_suspend+0x60/0xa0)
    [<c02a1954>] (gpio_keys_suspend) from [<c023b750>] (platform_pm_suspend+0x3c/0x5c)

Avoid this false positive by using a separate lockdep class for INTC
External IRQ Pin interrupts.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1441798974-25716-3-git-send-email-geert%2Brenesas@glider.be
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-09-15 17:06:29 +02:00
Krzysztof Kozlowski
9600973656 irqchip: Constify irq_domain_ops
The irq_domain_ops are not modified by the driver and the irqdomain core
code accepts pointer to a const data.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Kukjin Kim <kgene@kernel.org>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Lee Jones <lee@kernel.org>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-rpi-kernel@lists.infradead.org
Cc: linux-mediatek@lists.infradead.org
Link: http://lkml.kernel.org/r/1430139264-4362-2-git-send-email-k.kozlowski.k@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-05-05 10:45:58 +02:00
Magnus Damm
e03f9088e2 irqchip: renesas-intc-irqpin: r8a7779 IRLM setup support
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: Magnus 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@w520
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-01-26 11:38:22 +01:00
Wolfram Sang
b79d4b7717 irqchip: drop owner assignment from platform_drivers
A platform_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-10-20 16:20:42 +02:00
Geert Uytterhoeven
705bc96c2c irqchip: renesas-intc-irqpin: Add minimal runtime PM support
This is just enough to let pm_clk_*() enable the functional clock, and
manage it for suspend/resume, if present.
Before, it was assumed enabled by the bootloader or reset state.

To prevent the clock from being disabled while the module is needed for
wake-up, implement irq_chip.irq_set_wake(), which increments/decrements
the clock's enable_count when needed.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lkml.kernel.org/r/1410527720-18061-3-git-send-email-geert+renesas@glider.be
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2014-09-14 06:47:40 +00:00
Geert Uytterhoeven
36845f1b54 irqchip: renesas-intc-irqpin: Add helper variable dev = &pdev->dev
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lkml.kernel.org/r/1410527720-18061-2-git-send-email-geert+renesas@glider.be
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2014-09-14 06:47:31 +00:00
Geert Uytterhoeven
1c36d42c4f irqchip: renesas-intc-irqpin: Add suspend-to-RAM wake up support
Set the ->irq_enable() and ->irq_disable() methods to NULL to enable
lazy disable of interrupts, and set IRQCHIP_MASK_ON_SUSPEND to tell the
core that only IRQs marked as wake-ups need to stay enabled during
suspend-to-RAM.

This makes wake-up by gpio-keys from suspend-to-RAM work on
r8a7740/Armadillo.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lkml.kernel.org/r/1408546172-22484-1-git-send-email-geert+renesas@glider.be
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2014-08-21 12:07:44 +00:00
Laurent Pinchart
e55bc55867 irqchip: renesas-intc-irqpin: Fix register bitfield shift calculation
The SENSE register bitfield position is incorrectly computed for SoCs
that use 2-bit IRQ sense fields. Fix it.

This has been tested on the Marzen (H1) and Bockw (M1) boards.

This bug has been present since the renesas-intc-irqpin driver was
introduced by 443580486e ("irqchip: Renesas INTC External IRQ pin
driver") in v3.10-rc1.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Magnus Damm <damm@opensource.se>
Tested-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
2013-11-24 15:55:17 +09:00
Guennadi Liakhovetski
c4fa4946f1 ARM: shmobile: irqpin: add a DT property to enable masking on parent
To disable spurious interrupts, that get triggered on certain hardware, the
irqpin driver masks them on the parent interrupt controller. To specify
such broken devices a .control_parent parameter can be provided in the
platform data. In the DT case we need a property, to do the same.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
2013-06-19 21:27:31 +09:00
Guennadi Liakhovetski
894db16426 irqchip: renesas-intc-irqpin: DT binding for sense bitfield width
Most Renesas irqpin controllers have 4-bit sense fields, however, some
have different widths. This patch adds a DT binding to optionally
specify such non-standard values.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski+renesas@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
2013-06-18 16:15:18 +09:00
Bastian Hecht
427cc72027 irqchip: intc-irqpin: Add support for shared interrupt lines
On some hardware we don't have a 1-1 mapping from the external
interrupts coming from INTC to the GIC SPI pins. We can however
share lines to demux incoming IRQs on these SoCs.

This patch enables the intc_irqpin driver to detect requests for shared
interrupt lines and demuxes them properly by querying the INTC INTREQx0A
registers.

If you need multiple shared intc_irqpin device instances, be sure to mask
out all interrupts on the INTC that share the one line before you start
to register them. Else you run into IRQ floods that would be caused by
interrupts for which no handler has been set up yet when the first
intc_irqpin device is registered.

Signed-off-by: Bastian Hecht <hechtb+renesas@gmail.com>
Acked-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
2013-03-28 16:39:46 +09:00
Magnus Damm
9d833bbe49 irqchip: intc-irqpin: Initial DT support
Add initial DT support to the INTC External IRQ Pin
driver. At this point only hardware with 4-bit wide
sense registers is supported via DT.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
2013-03-18 21:26:07 +09:00
Magnus Damm
08eba5ba4f irqchip: intc-irqpin: Make use of devm functions
Use devm_kzalloc(), devm_ioremap_nocache()
and devm_request_irq() to simplify error
handling.

Signed-off-by: Magnus Damm <damm@opensource.se>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
2013-03-18 21:26:06 +09:00
Magnus Damm
d1b6aecde4 irqchip: intc-irqpin: Add force comments
Add comments to describe the special case for
"force" versions of enable and disable functions.

Signed-off-by: Magnus Damm <damm@opensource.se>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
2013-03-18 21:26:06 +09:00
Magnus Damm
33f958f2a7 irqchip: intc-irqpin: Cache mapped IRQ
Cache IRQ in domain_irq variable instead of
making use of irq_find_mapping(). While at it
rename the irq variable to requested_irq.

Signed-off-by: Magnus Damm <damm@opensource.se>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
2013-03-18 21:26:06 +09:00
Magnus Damm
862d309883 irqchip: intc-irqpin: Whitespace fixes
Remove whitespace damage and add newline
between variables and code.

Signed-off-by: Magnus Damm <damm@opensource.se>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
2013-03-18 21:26:06 +09:00
Magnus Damm
443580486e irqchip: Renesas INTC External IRQ pin driver
This patch adds a driver for external IRQ pins connected
to the INTC block on recent SoCs from Renesas.

The INTC hardware block usually contains a rather wide
range of features ranging from external IRQ pin handling
to legacy interrupt controller support. On older SoCs
the INTC is used as a general purpose interrupt controller
both for external IRQ pins and on-chip devices.

On more recent ARM based SoCs with Cortex-A9 the main
interrupt controller is the GIC, but IRQ trigger setup
still need to happen in the INTC hardware block.

This driver implements the glue code needed to configure
IRQ trigger and also handle mask/unmask and demux of
external IRQ pins hooked up from the INTC to the GIC.

Tested on sh73a0 and r8a7779. The hardware varies quite
a bit with SoC model, for instance register width and
bitfield widths vary wildly. The driver requires one GIC
SPI per external IRQ pin to operate.  Each driver instance
will handle up to 8 external IRQ pins.

The SoCs using this driver are currently mainly used
together with regular platform devices so this driver
allows configuration via platform data to support things
like static interrupt base address. DT support will
be added incrementally in the not so distant future.

Signed-off-by: Magnus Damm <damm@opensource.se>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
2013-03-18 21:26:05 +09:00