Re: [PATCH 04/10] arm64: dts: juno: use proper 'dma-channels/requests' properties

From: Robin Murphy <robin.murphy@arm.com>
To: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
	Lee Jones <lee.jones@linaro.org>,
	Rob Herring <robh+dt@kernel.org>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	Alim Akhtar <alim.akhtar@samsung.com>,
	Dinh Nguyen <dinguyen@kernel.org>,
	Michal Simek <michal.simek@xilinx.com>,
	Liviu Dudau <liviu.dudau@arm.com>,
	Sudeep Holla <sudeep.holla@arm.com>,
	Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
	Ray Jui <rjui@broadcom.com>,
	Scott Branden <sbranden@broadcom.com>,
	Broadcom Kernel Team <bcm-kernel-feedback-list@broadcom.com>,
	Sylwester Nawrocki <s.nawrocki@samsung.com>,
	devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	linux-samsung-soc@vger.kernel.org, linux-kernel@vger.kernel.org
Cc: Rob Herring <robh@kernel.org>
Subject: Re: [PATCH 04/10] arm64: dts: juno: use proper 'dma-channels/requests' properties
Date: Thu, 28 Apr 2022 11:43:01 +0100	[thread overview]
Message-ID: <1d1aae6e-50db-d6db-9727-62f9c2d1ca6b@arm.com> (raw)
In-Reply-To: <20220427155840.596535-5-krzysztof.kozlowski@linaro.org>

On 2022-04-27 16:58, Krzysztof Kozlowski wrote:
> pl330 DMA controller bindings documented 'dma-channels' and
> 'dma-requests' properties (without leading hash sign), so fix the DTS to
> match the bindings.
> 
> Reported-by: Rob Herring <robh@kernel.org>
> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
> ---
>   arch/arm64/boot/dts/arm/juno-base.dtsi | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arm64/boot/dts/arm/juno-base.dtsi b/arch/arm64/boot/dts/arm/juno-base.dtsi
> index 4f40a5c8f565..96ef0ddc0b2d 100644
> --- a/arch/arm64/boot/dts/arm/juno-base.dtsi
> +++ b/arch/arm64/boot/dts/arm/juno-base.dtsi
> @@ -829,8 +829,8 @@ dma-controller@7ff00000 {
>   		compatible = "arm,pl330", "arm,primecell";
>   		reg = <0x0 0x7ff00000 0 0x1000>;
>   		#dma-cells = <1>;
> -		#dma-channels = <8>;
> -		#dma-requests = <32>;
> +		dma-channels = <8>;
> +		dma-requests = <32>;

BTW, this has always been wrong - Juno is configured with only 8 request 
interfaces. But then it's moot anyway since PL330 has an ID register for 
this stuff[1], so the DT properties aren't used by Linux, and shouldn't 
be needed in general.

Thanks,
Robin.

[1] 
https://developer.arm.com/documentation/ddi0424/d/programmers-model/register-descriptions/configuration-register-0?lang=en

>   		interrupts = <GIC_SPI 88 IRQ_TYPE_LEVEL_HIGH>,
>   			     <GIC_SPI 89 IRQ_TYPE_LEVEL_HIGH>,
>   			     <GIC_SPI 90 IRQ_TYPE_LEVEL_HIGH>,