Some GIC revisions require an individual configuration to esp. add
workarounds for HW bugs. This patch implements generic code to parse
the hw revision provided by an IIDR register value and runs specific
code if hw matches. A function is added that reads the IIDR registers
for ITS (GITS_IIDR) and then goes through a list of init functions to
be called for specific versions. Same could be done for GICV3
(GICD_IIDR), but there are no users yet for it.

The patch is needed to implement workarounds for HW errata in Cavium's
ThunderX GICV3 ITS.
Signed-off-by: NRobert Richter <rrichter@cavium.com>
Reviewed-by: NMarc Zygnier <marc.zyngier@arm.com>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Cc: Tirumalesh Chalamarla <tchalamarla@cavium.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1442869119-1814-5-git-send-email-rric@kernel.orgSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

GIC requires to disable the interrupt before changing the trigger type.
irqchip core provides IRQCHIP_SET_TYPE_MASKED flag and ensures that the
interrupt is masked before calling chip.irq_set_type() if the irqchip
sets the flag.

This patch adds IRQCHIP_SET_TYPE_MASKED to GIC irqchip so that the core
can manage disabling the interrupt while changing the trigger type.
Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>
Reviewed-by: NMarc Zyngier <marc.zyngier@arm.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1433501997-19205-1-git-send-email-sudeep.holla@arm.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

During a recent cleanup of the arm64 DTs it has become clear that
the handling of PPIs in xxxx_set_type() is incorrect. The ARM TRMs
for GICv2 and later allow for "implementation defined" support for
setting the edge or level type of the PPI interrupts and don't restrict
the activation level of the signal. Current ARM implementations
do restrict the PPI level type to IRQ_TYPE_LEVEL_LOW, but licensees
of the IP can decide to shoot themselves in the foot at any time.
Signed-off-by: NLiviu Dudau <Liviu.Dudau@arm.com>
Acked-by: NMarc Zyngier <Marc.Zyngier@arm.com>
Cc: LAKML <linux-arm-kernel@lists.infradead.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Haojian Zhuang <haojian.zhuang@linaro.org>
Link: http://lkml.kernel.org/r/1421772779-25764-1-git-send-email-Liviu.Dudau@arm.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

This is to cleanup some hex numbers used in the code and replace
them with defines to make the code cleaner.
Signed-off-by: NFeng Kan <fkan@apm.com>
Reviewed-by: NAnup Patel <apatel@apm.com>
Link: https://lkml.kernel.org/r/1406757419-18729-2-git-send-email-fkan@apm.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

A few GICv2 low-level function are actually very useful to GICv3,
and it makes some sense to share them across the two drivers.
They end-up in their own file, with an additional parameter used
to ensure an optional synchronization (unused on GICv2).

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Acked-by: NChristoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/1404140510-5382-2-git-send-email-marc.zyngier@arm.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>