Re: [PATCH 1/2] dt-bindings: arm: bcm: raspberrypi,bcm2835-firmware: Add missing properties

From: Dave Stevenson <dave.stevenson@raspberrypi.com>
To: Stefan Wahren <wahrenst@gmx.net>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
	 Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
	devicetree@vger.kernel.org,
	 linux-rpi-kernel@lists.infradead.org,
	linux-arm-kernel@lists.infradead.org,
	 linux-gpio@vger.kernel.org, Rob Herring <robh@kernel.org>,
	 Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	Conor Dooley <conor+dt@kernel.org>,
	 Florian Fainelli <florian.fainelli@broadcom.com>,
	 Broadcom internal kernel review list
	<bcm-kernel-feedback-list@broadcom.com>,
	Ray Jui <rjui@broadcom.com>,
	 Scott Branden <sbranden@broadcom.com>,
	Linus Walleij <linus.walleij@linaro.org>,
	 Bartosz Golaszewski <brgl@bgdev.pl>
Subject: Re: [PATCH 1/2] dt-bindings: arm: bcm: raspberrypi,bcm2835-firmware: Add missing properties
Date: Tue, 26 Mar 2024 18:41:30 +0000	[thread overview]
Message-ID: <CAPY8ntDnLXTeep1GQxrZvxzi=F7zDoasto0BVRvN9_h5joE96g@mail.gmail.com> (raw)
In-Reply-To: <45242028-edf7-49fc-80bf-be9eb242b4cd@gmx.net>

On Tue, 26 Mar 2024 at 11:47, Stefan Wahren <wahrenst@gmx.net> wrote:
>
> [add Dave since he's working on DMA for Raspberry Pi 4 and maybe have a
> opinion about this]

No real opinion from me, but I am far from a DT expert, and AFAIK this
bit isn't impacted by the stuff I'm looking at.

Laurent is correct that it's missing from the binding doc when it
looks to be needed. Adding it would therefore be the correct thing to
do.

  Dave

> [drop Emma Anholt old address since she is not involved anymore]
>
> Am 26.03.24 um 08:06 schrieb Krzysztof Kozlowski:
> > On 26/03/2024 01:49, Laurent Pinchart wrote:
> >> The raspberrypi,bcm2835-firmware devices requires a dma-ranges property,
> >> and, as a result, also needs to specify #address-cells and #size-cells.
> >> Those properties have been added to thebcm2835-rpi.dtsi in commits
> >> be08d278eb09 ("ARM: dts: bcm283x: Add cells encoding format to firmware
> >> bus") and 55c7c0621078 ("ARM: dts: bcm283x: Fix vc4's firmware bus DMA
> >> limitations"), but the DT bindings haven't been updated, resulting in
> >> validation errors:
> >>
> >> arch/arm64/boot/dts/broadcom/bcm2711-rpi-4-b.dtb: firmware: '#address-cells', '#size-cells', 'dma-ranges', 'gpio' do not match any of the regexes: 'pinctrl-[0-9]+'
> >>          from schema $id: http://devicetree.org/schemas/arm/bcm/raspberrypi,bcm2835-firmware.yaml#
> >>
> >> Fix this by adding the properties to the bindings.
> >>
> >> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> > Children do not perform any IO on their own, because everything is
> > handled by parent. It is really odd to see dma-ranges without ranges.
> > Referenced commits might be also wrong.
> >
> > Best regards,
> > Krzysztof
> >
> >
> > _______________________________________________
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> > linux-arm-kernel@lists.infradead.org
> > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>