Re: [PATCH v2 06/14] irqchip: add initial support for ompic

From: Rob Herring
Date: Mon Sep 18 2017 - 16:43:59 EST


On Sun, Sep 10, 2017 at 03:49:18PM +0900, Stafford Horne wrote:
> From: Stefan Kristiansson <stefan.kristiansson@xxxxxxxxxxxxx>
>
> IPI driver for the Open Multi-Processor Interrupt Controller (ompic) as
> described in the Multicore support section of the OpenRISC 1.2
> proposed architecture specification:
>
> https://github.com/stffrdhrn/doc/raw/arch-1.2-proposal/openrisc-arch-1.2-rev0.pdf
>
> Each OpenRISC core contains a full interrupt controller which is used in
> the SMP architecture for interrupt balancing. This IPI device, the
> ompic, is the only external device required for enabling SMP on
> OpenRISC.
>
> Pending ops are stored in a memory bit mask which can allow multiple
> pending operations to be set and serviced at a time. This is mostly
> borrowed from the alpha IPI implementation.
>
> Signed-off-by: Stefan Kristiansson <stefan.kristiansson@xxxxxxxxxxxxx>
> [shorne@xxxxxxxxx: converted ops to bitmask, wrote commit message]
> Signed-off-by: Stafford Horne <shorne@xxxxxxxxx>
> ---
>
> Changes since v1
> - Added openrisc, prefix
> - Clarified 8 bytes per cpu
> - Removed #interrupt-cells as this will not be an irq parent

You should still have #interrupt-cells as that is required with
"interrupt-controller". It could be 0 though.

> - Changed ops to be percpu
> - Added DTS and intialization failure validations
>
> .../interrupt-controller/openrisc,ompic.txt | 19 ++
> arch/openrisc/Kconfig | 1 +
> drivers/irqchip/Kconfig | 3 +
> drivers/irqchip/Makefile | 1 +
> drivers/irqchip/irq-ompic.c | 205 +++++++++++++++++++++
> 5 files changed, 229 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/interrupt-controller/openrisc,ompic.txt
> create mode 100644 drivers/irqchip/irq-ompic.c
>
> diff --git a/Documentation/devicetree/bindings/interrupt-controller/openrisc,ompic.txt b/Documentation/devicetree/bindings/interrupt-controller/openrisc,ompic.txt
> new file mode 100644
> index 000000000000..346e6042d62f
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/interrupt-controller/openrisc,ompic.txt
> @@ -0,0 +1,19 @@
> +Open Multi-Processor Interrupt Controller
> +
> +Required properties:
> +
> +- compatible : This should be "openrisc,ompic"
> +- reg : Specifies base physical address and size of the register space. The
> + size is based on the number of cores the controller has been configured
> + to handle, this should be set to 8 bytes per cpu core.
> +- interrupt-controller : Identifies the node as an interrupt controller
> +- interrupts : Specifies the interrupt line to which the ompic is wired.
> +
> +Example:
> +
> +ompic: ompic {

interrupt-controller@98000000 {

> + compatible = "openrisc,ompic";
> + reg = <0x98000000 16>;
> + interrupt-controller;
> + interrupts = <1>;
> +};