[PATCH v2 2/4] irqchip: bcm2835: If a parent interrupt is registered, chain from it.

Stephen Warren swarren at wwwdotorg.org
Tue Jul 21 19:08:29 PDT 2015

On 07/13/2015 07:35 PM, Eric Anholt wrote:
> The BCM2836 (Raspberry Pi 2) uses two levels of interrupt handling
> with the CPU-local interrupts being the root, so we need to register
> ours as chained off of the CPU's local interrupt.

Sorry for the slow review; laziness after vacation!

> diff --git a/Documentation/devicetree/bindings/interrupt-controller/brcm,bcm2835-armctrl-ic.txt b/Documentation/devicetree/bindings/interrupt-controller/brcm,bcm2835-armctrl-ic.txt

> +The BCM2836 contains the same interrupt controller with the same
> +interrupts, but the per-CPU interrupt controller is the root, and an
> +interrupt there indicates that the ARMCTRL has an interrupt to handle.
> +
>  Required properties:
>  - compatible : should be "brcm,bcm2835-armctrl-ic"

Since there are some differences between the bcm2835 and bcm2836 HW
blocks, I'd expect the compatible value to be different for each. In

> +Optional properties:
> +- interrupt-parent : Specifies the parent interrupt controller when this
> +  controller is the second level.
> +- interrupts : Specifies the interrupt on the parent for this interrupt
> +  controller to handle.

I'd classify that as "additional required properties for

... and with different compatible values for the two chips, you would
know when probe() should require vs. reject the property.

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