Re: [PATCH] irqchip: Add support for Renesas RZ/N1 GPIO interrupt multiplexer

From: Rob Herring
Date: Tue May 01 2018 - 09:28:54 EST


On Mon, Apr 23, 2018 at 02:33:06PM +0100, Phil Edworthy wrote:
> On RZ/N1 devices, there are 3 Synopsys DesignWare GPIO blocks each
> configured to have 32 interrupt outputs, so we have a total of 96 GPIO
> interrupts. All of these are passed to the GPIO IRQ Muxer, which selects
> 8 of the GPIO interrupts to pass onto the GIC. The interrupt signals
> aren't latched, so there is nothing to do in this driver when an interrupt
> is received, other than tell the corresponding GPIO block.
>
> Signed-off-by: Phil Edworthy <phil.edworthy@xxxxxxxxxxx>
> ---
> .../interrupt-controller/renesas,rzn1-mux.txt | 85 ++++++++++

Please split bindings to a separate patch.

> drivers/irqchip/Kconfig | 10 ++
> drivers/irqchip/Makefile | 1 +
> drivers/irqchip/irq-rzn1-irq-mux.c | 178 +++++++++++++++++++++
> 4 files changed, 274 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/interrupt-controller/renesas,rzn1-mux.txt
> create mode 100644 drivers/irqchip/irq-rzn1-irq-mux.c
>
> diff --git a/Documentation/devicetree/bindings/interrupt-controller/renesas,rzn1-mux.txt b/Documentation/devicetree/bindings/interrupt-controller/renesas,rzn1-mux.txt
> new file mode 100644
> index 0000000..f28a365
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/interrupt-controller/renesas,rzn1-mux.txt
> @@ -0,0 +1,85 @@
> +* Renesas RZ/N1 GPIO Interrupt Multiplexer
> +
> +On Renesas RZ/N1 devices, there are 3 Synopsys DesignWare GPIO blocks each
> +configured to have 32 interrupt outputs, so we have a total of 96 GPIO
> +interrupts. All of these are passed to the GPIO IRQ Muxer, which selects
> +8 of the GPIO interrupts to pass onto the GIC.
> +
> +A single node in the device tree is used to describe the GPIO IRQ Muxer.
> +
> +Required properties:
> +- compatible: the SoC specific name, i.e. "renesas,r9a06g032-gpioirq"
> + or "renesas,r9a06g033-gpioirq" followed by the SoC family name, i.e.
> + "renesas,rzn1-gpioirq".
> +- interrupt-controller: Identifies the node as an interrupt controller.
> +- #interrupt-cells: should be <1>. The meaning of the cells is the input
> + interrupt index, 0 to 95.
> +- reg: Base address and size of GPIO IRQ Muxer registers.
> +- interrupts: The list of interrupts generated by the muxer which are then
> + connected to a parent interrupt controller. The format of the interrupt
> + specifier depends in the interrupt parent controller.
> +- gpioirq-#N: One property for each interrupt output from the GPIO IRQ Muxer
> + that specifies the input interrupt to use, #N is from 0 to 7.

Why do you need this in DT? Can't the driver handle this dynamically?
When you request an interrupt on a GPIO line, then connect that GPIO
line to a free IRQ line.

If you really need this in DT, then interrupt-map can be used here.

> +
> +Optional properties:
> +- interrupt-parent: pHandle of the parent interrupt controller, if not
> + inherited from the parent node.
> +
> +
> +Example:
> +
> + The following is an example for the RZ/N1D SoC.
> +
> + gpioirq: gpioirq@51000480 {
> + compatible = "renesas,r9a06g032-gpioirq",
> + "renesas,rzn1-gpioirq";
> + reg = <0x51000480 0x20>;
> + interrupts =
> + <GIC_SPI 103 IRQ_TYPE_LEVEL_HIGH>,
> + <GIC_SPI 104 IRQ_TYPE_LEVEL_HIGH>,
> + <GIC_SPI 105 IRQ_TYPE_LEVEL_HIGH>,
> + <GIC_SPI 106 IRQ_TYPE_LEVEL_HIGH>,
> + <GIC_SPI 107 IRQ_TYPE_LEVEL_HIGH>,
> + <GIC_SPI 108 IRQ_TYPE_LEVEL_HIGH>,
> + <GIC_SPI 109 IRQ_TYPE_LEVEL_HIGH>,
> + <GIC_SPI 110 IRQ_TYPE_LEVEL_HIGH>;
> + interrupt-controller;
> + #interrupt-cells = <1>;
> + status = "disabled";

Don't show status in examples.

> + };
> +
> + gpio0: gpio@5000b000 {
> + compatible = "snps,dw-apb-gpio";
> + reg = <0x5000b000 0x80>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + clock-names = "bus";
> + clocks = <&hclk_gpio0>;
> + status = "disabled";
> +
> + gpio0a: gpio-controller@0 {
> + compatible = "snps,dw-apb-gpio-port";
> + bank-name = "gpio0a";
> + gpio-controller;
> + #gpio-cells = <2>;
> + snps,nr-gpios = <32>;
> + reg = <0>;
> +
> + interrupt-controller;
> + interrupt-parent = <&gpioirq>;
> + interrupts = < 0 1 2 3 4 5 6 7
> + 8 9 10 11 12 13 14 15
> + 16 17 18 19 20 21 22 23
> + 24 25 26 27 28 29 30 31 >;
> + #interrupt-cells = <2>;
> + };
> + };
> +
> +
> + The following is an example for a board using this.

Don't show the soc/board split. This is convention, but not part of the
binding.

> +
> + &gpioirq {
> + status = "okay";
> + gpioirq-0 = <24>; /* gpio0a 24 */
> + gpioirq-4 = <3>; /* gpio0a 3 */
> + };