[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...
More information about the linux-arm-kernel
mailing list