[PATCH v9 1/4] dt-binding:Documents of the mbigen bindings

[Mark Rutland]

Hi,

On Mon, Nov 23, 2015 at 11:15:10AM +0800, MaJun wrote:
> From: Ma Jun <majun258 at huawei.com>
> 
> Add the mbigen msi interrupt controller bindings document.
> 
> This patch based on Mark Rutland's patch
> https://lkml.org/lkml/2015/7/23/558
> 
> Signed-off-by: Ma Jun <majun258 at huawei.com>
> ---
>  Documentation/devicetree/bindings/arm/mbigen.txt |   69 ++++++++++++++++++++++
>  1 files changed, 69 insertions(+), 0 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/arm/mbigen.txt
> 
> diff --git a/Documentation/devicetree/bindings/arm/mbigen.txt b/Documentation/devicetree/bindings/arm/mbigen.txt
> new file mode 100644
> index 0000000..8ae59a9
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/arm/mbigen.txt
> @@ -0,0 +1,69 @@
> +Hisilicon mbigen device tree bindings.
> +=======================================
> +
> +Mbigen means: message based interrupt generator.
> +
> +MBI is kind of msi interrupt only used on Non-PCI devices.
> +
> +To reduce the wired interrupt number connected to GIC,
> +Hisilicon designed mbigen to collect and generate interrupt.
> +
> +
> +Non-pci devices can connect to mbigen and generate the
> +interrupt by writing ITS register.
> +
> +The mbigen chip and devices connect to mbigen have the following properties:
> +
> +Mbigen main node required properties:
> +-------------------------------------------
> +- compatible: Should be "hisilicon,mbigen-v2"
> +- reg: Specifies the base physical address and size of the Mbigen
> +  registers.
> +- interrupt controller: Identifies the node as an interrupt controller
> +- msi-parent: This property has two cells.
> +	The 1st cell specifies the ITS this device connected.
> +	The 2nd cell specifies the device id.

This should just refer to the generic msi-parent binding in
Documentation/devicetree/bindings/interrupt-controller/msi.txt.

I assume that the driver does not try to parse this itself (i.e. it uses
generic accessors and doesn't assume anything about the meaning of these
cells).

> +- num-msis:Specifies the total number of interrupt this device has.
> +- #interrupt-cells : Specifies the number of cells needed to encode an
> +  interrupt source. The value must be 2.
> +
> +  The 1st cell is global hardware pin number of the interrupt.
> +	This value depends on the Soc design.

I think a little more information is required here. Presumably the
"global hardware pin number" is actually a pin number within the
particular mbigen instance? i.e. it is local to this instance?

> +  The 2nd cell is the interrupt trigger type.
> +	The value of this cell should be:
> +	1: rising edge triggered
> +	or
> +	4: high level triggered	
> +
> +Examples:
> +
> + 	mbigen_device_gmac:intc {
> +			compatible = "hisilicon,mbigen-v2";
> +			reg = <0x0 0xc0080000 0x0 0x10000>;
> +			interrupt-controller;
> +			msi-parent = <&its_dsa 0x40b1c>;
> +			num-msis = <9>;
> +			#interrupt-cells = <2>;
> + 	};
> +
> +Devices connect to mbigen required properties:
> +----------------------------------------------------
> +-interrupt-parent: Specifies the mbigen device node which device connected.
> +-interrupts:specifies the interrupt source.
> +  The 1st cell is global hardware pin number of the interrupt.
> +		This value depends on the Soc design.
> +  The 2nd cell is the interrupt trigger type(rising edge triggered or high
> +		level triggered)

You should be able to refer to the usual interrupt bindings given you
defined the format previously when describing #interrupt-cells.

Thanks,
Mark.