Re: [RFC PATCH 1/2] dt-bindings: irqchip: Update bindings to drop the usage of gic as parent

From: Marc Zyngier <maz@kernel.org>
To: Lokesh Vutla <lokeshvutla@ti.com>
Cc: Nishanth Menon <nm@ti.com>,
	Linux ARM Mailing List <linux-arm-kernel@lists.infradead.org>
Subject: Re: [RFC PATCH 1/2] dt-bindings: irqchip: Update bindings to drop the usage of gic as parent
Date: Wed, 2 Oct 2019 13:57:57 +0100	[thread overview]
Message-ID: <20191002135757.28901015@why> (raw)
In-Reply-To: <20190923042405.26064-2-lokeshvutla@ti.com>

On Mon, 23 Sep 2019 09:54:04 +0530
Lokesh Vutla <lokeshvutla@ti.com> wrote:

> Drop the firmware related dt-bindings and use the hardware specified
> interrupt numbers within Interrupt Router. This ensures interrupt router
> DT node need not assume any interrupt parent type.
> 
> Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
> ---
>  .../interrupt-controller/ti,sci-intr.txt      | 28 +++++++++----------
>  1 file changed, 13 insertions(+), 15 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/interrupt-controller/ti,sci-intr.txt b/Documentation/devicetree/bindings/interrupt-controller/ti,sci-intr.txt
> index 1a8718f8855d..de5de2a4b467 100644
> --- a/Documentation/devicetree/bindings/interrupt-controller/ti,sci-intr.txt
> +++ b/Documentation/devicetree/bindings/interrupt-controller/ti,sci-intr.txt
> @@ -44,15 +44,14 @@ Required Properties:
>  			4: If intr supports level triggered interrupts.
>  - interrupt-controller:	Identifies the node as an interrupt controller
>  - #interrupt-cells:	Specifies the number of cells needed to encode an
> -			interrupt source. The value should be 2.
> -			First cell should contain the TISCI device ID of source
> -			Second cell should contain the interrupt source offset
> -			within the device.
> +			interrupt source. The value should be 1.
> +			First cell should contain interrupt router input number
> +			as specified by hardware.

This is breaking compatibility with existing kernels. Why isn't that a
problem?

> +- power-domains:	phandle pointing to the corresponding PM domain node
> +			and an ID representing the device.

Why is this power-domain thing part of this patch? Is it related?

>  - ti,sci:		Phandle to TI-SCI compatible System controller node.
> -- ti,sci-dst-id:	TISCI device ID of the destination IRQ controller.
> -- ti,sci-rm-range-girq:	Array of TISCI subtype ids representing the host irqs
> -			assigned to this interrupt router. Each subtype id
> -			corresponds to a range of host irqs.
> +- interrupt-ranges:	Ranges that convert the INTR output interrupt numbers to
> +			parent's interrupt number.

This isn't a standard property, is it? If it isn't, it should be
documented a bit more than just that.

>  
>  For more details on TISCI IRQ resource management refer:
>  http://downloads.ti.com/tisci/esd/latest/2_tisci_msgs/rm/rm_irq.html
> @@ -62,21 +61,20 @@ Example:
>  The following example demonstrates both interrupt router node and the consumer
>  node(main gpio) on the AM654 SoC:
>  
> -main_intr: interrupt-controller0 {
> +main_gpio_intr: interrupt-controller0 {
>  	compatible = "ti,sci-intr";
>  	ti,intr-trigger-type = <1>;
>  	interrupt-controller;
>  	interrupt-parent = <&gic500>;
> -	#interrupt-cells = <2>;
> +	power-domains = <&k3_pds 131 TI_SCI_PD_SHARED>;
> +	#interrupt-cells = <1>;
>  	ti,sci = <&dmsc>;
> -	ti,sci-dst-id = <56>;
> -	ti,sci-rm-range-girq = <0x1>;
> +	interrupt-ranges = <0 360 32>;
>  };
>  
>  main_gpio0: gpio@600000 {
>  	...
> -	interrupt-parent = <&main_intr>;
> -	interrupts = <57 256>, <57 257>, <57 258>,
> -		     <57 259>, <57 260>, <57 261>;
> +	interrupt-parent = <&main_gpio_intr>;
> +	interrupts = <192>, <193>, <194>, <195>, <196>, <197>;
>  	...
>  };

Thanks,

	M.
-- 
Without deviation from the norm, progress is not possible.

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel