Re: [PATCH v11 0/2] irqchip: add support for GICv2m MSI controller

[Jason Cooper <jason@lakedaemon.net>]

On Tue, Nov 25, 2014 at 06:47:21PM +0000, Marc Zyngier wrote:
> GICv2m is a very simple addition to the standard GICv2 interrupt
> controller, offering a way to convert writes from a device to a
> "wire-like" interrupt. Basically what we need to support MSI on the
> GIC.
> 
> The v2m widget exposes a "frame", containing a read-only register
> describing the range of interrupts that are MSI-capable, as well as a
> doorbell that the device can kick to generate the interrupt. All the
> rest of the infrastructure is provided by the GIC itself (enabling,
> routing, ack/eoi...). This makes an ideal case for stacked irq
> domains.
> 
> These patches were originally written by Suravee, but I've converted
> them to the stacked irq domains. As this turned out to be quite a
> sizeable rewrite of the original code, please blame me for any issue
> in this code, and not Suravee.
> 
> Unsurprisingly, there is quite a long dependency chain here. You need:
> - Jiang's stacked domain patches, from tip/irq/irqdomain
> - The first patch in my GICv3 ITS series:
>   https://lkml.org/lkml/2014/11/24/409
> - The first patch in Yingjoe's sysirq series:
>   https://lkml.org/lkml/2014/11/25/130
> 
> For everyone's convenience, I have a branch containing all that, and
> much more:
> 
> git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms.git irq/v2m
> 
> This has been fairly heavily tested on an arm64 platform driving a
> pair of igb interfaces.
> 
> From v10:
> - Rewrote the driver to solely rely on irq domains, and not the
> setup_irq/teardown_irq methods that were used before (similar to what
> has been done for the GICv3 ITS).
> 
> Suravee Suthikulpanit (2):
>   irqchip: gicv2m: Add support for ARM GICv2m MSI(-X) doorbell
>   irqchip: gicv2m: Add DT bindings for GICv2m
> 
>  Documentation/devicetree/bindings/arm/gic.txt |  53 ++++
>  arch/arm64/Kconfig                            |   1 +
>  drivers/irqchip/Kconfig                       |   6 +
>  drivers/irqchip/Makefile                      |   1 +
>  drivers/irqchip/irq-gic-v2m.c                 | 333 ++++++++++++++++++++++++++
>  drivers/irqchip/irq-gic.c                     |   4 +
>  include/linux/irqchip/arm-gic.h               |   2 +
>  7 files changed, 400 insertions(+)
>  create mode 100644 drivers/irqchip/irq-gic-v2m.c

Both added to irqchip/core

thx,

Jason.