[PATCH v8 1/4] dt-binding:Documents of the mbigen bindings

Marc Zyngier marc.zyngier at arm.com
Wed Nov 18 09:50:52 PST 2015


On 06/11/15 08:28, 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 |   63 ++++++++++++++++++++++
>  1 files changed, 63 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..eb9a7fd
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/arm/mbigen.txt
> @@ -0,0 +1,63 @@
> +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.
> +- nr-msis:Specifies the total number of interrupt this device has.

So here you have the nr-msis property...

> +- #interrupt-cells : Specifies the number of cells needed to encode an
> +  interrupt source. The value is 2 now.
> +

Just say "Must be 2".

> +  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.
> +
> +Examples:
> +
> + 	mbigen_device_gmac:intc {
> +			compatible = "hisilicon,mbigen-v2";
> +			reg = <0x0 0xc0080000 0x0 0x10000>;
> +			interrupt-controller;
> +			msi-parent = <&its_dsa 0x40b1c>;
> +			num-msis = <9>;

... and here this is num-msis.

Which one is it? The driver seems to use num-msis as well, but I have no
idea which one is the right one.

> +			#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
> +
> +Examples:
> +	gmac0: ethernet at c2080000 {
> +		#address-cells = <1>;
> +		#size-cells = <0>;
> +		reg = <0 0xc2080000 0 0x20000>,
> +		      <0 0xc0000000 0 0x1000>;
> +		interrupt-parent  = <&mbigen_device_gmac>;
> +		interrupts =	<656 1>,
> +				<657 1>;
> +	};
> +
> 

Thanks,

	M.
-- 
Jazz is not dead. It just smells funny...



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