Re: [PATCH RFC 2/4] dt-bindings/interrupt-controller: pdc: descibe PDC device binding

From: Marc Zyngier
Date: Wed Jan 24 2018 - 09:24:13 EST


On 23/01/18 17:56, Lina Iyer wrote:
> From: Archana Sathyakumar <asathyak@xxxxxxxxxxxxxx>
>
> Add device binding documentation for the PDC Interrupt controller on
> QCOM SoC's like the SDM845. The interrupt-controller can be used to
> sense edge low interrupts and wakeup interrupts when the GIC is
> non-operational.
>
> Cc: devicetree@xxxxxxxxxxxxxxx
> Signed-off-by: Archana Sathyakumar <asathyak@xxxxxxxxxxxxxx>
> Signed-off-by: Lina Iyer <ilina@xxxxxxxxxxxxxx>
> ---
> .../bindings/interrupt-controller/qcom,pdc.txt | 55 ++++++++++++++++++++++
> 1 file changed, 55 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/interrupt-controller/qcom,pdc.txt
>
> diff --git a/Documentation/devicetree/bindings/interrupt-controller/qcom,pdc.txt b/Documentation/devicetree/bindings/interrupt-controller/qcom,pdc.txt
> new file mode 100644
> index 000000000000..c4592bbf678d
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/interrupt-controller/qcom,pdc.txt
> @@ -0,0 +1,55 @@
> +PDC interrupt controller
> +
> +Qualcomm Technologies Inc. SoCs based on the RPM Hardened archicture have a
nit: architecture

> +Power Domain Controller (PDC) that is on always-on domain. In addition to
> +providing power control for the power domains, the hardware also has an
> +interrupt controller that can be used to help detect edge low interrupts as
> +well detect interrupts when the GIC is non-operational.
> +
> +GIC is parent interrupt controller at the highest level. Platform interrupt
> +controller PDC is next in hierarchy, followed by others. This driver only
> +configures the interrupts, does not handle them.
> +
> +Properties:
> +
> +- compatible:
> + Usage: required
> + Value type: <string>
> + Definition: Should contain "qcom,pdc" and "qcom,pdc-<target>"
> + - "qcom,pdc-sdm845": For sdm845 pin data
> +
> +- reg:
> + Usage: required
> + Value type: <prop-encoded-array>
> + Definition: Specifies the base physical address for PDC hardware.
> +
> +- interrupt-cells:
> + Usage: required
> + Value type: <u32>
> + Definition: Specifies the number of cells needed to encode an interrupt
> + source.
> + Value must be 3.
> + The encoding of these cells are same as described in [1].

The GICv3 binding allows for more cells (at least 4), so you'll have to
adapt both in the binding and in the driver.

> +
> +- interrupt-parent:
> + Usage: required
> + Value type: <phandle>
> + Definition: Specifies the interrupt parent necessary for hierarchical
> + domain to operate.
> +
> +- interrupt-controller:
> + Usage: required
> + Value type: <bool>
> + Definition: Identifies the node as an interrupt controller.
> +
> +Example:
> +
> + pdc: interrupt-controller@b220000 {
> + compatible = "qcom,pdc", "qcom,pdc-sdm845";
> + reg = <0xb220000 0x30000>;
> + #interrupt-cells = <3>;
> + interrupt-parent = <&intc>;
> + interrupt-controller;
> + };
> +
> +[1]. Documentation/devicetree/bindings/interrupt-controller/arm,gic-v3.txt
>

You'll also have to specify the ranges for the pin to SPI mapping.

Thanks,

M.
--
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