linux-kernel - Re: [PATCH] ARM: dts: integrator: Fix DMA ranges mismatch warning on IM-PD1

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <CAD++jLneTBUyMDod_fbJbuy2Y4errGQpWM3H8uVdYbKZeUNEAw@mail.gmail.com>
Date: Wed, 24 Dec 2025 21:57:02 +0100
From: Linus Walleij <linusw@...nel.org>
To: Kuan-Wei Chiu <visitorckw@...il.com>
Cc: linus.walleij@...aro.org, robh@...nel.org, krzk+dt@...nel.org, 
	conor+dt@...nel.org, arnd@...db.de, jserv@...s.ncku.edu.tw, 
	linux-arm-kernel@...ts.infradead.org, devicetree@...r.kernel.org, 
	linux-kernel@...r.kernel.org, stable@...r.kernel.org
Subject: Re: [PATCH] ARM: dts: integrator: Fix DMA ranges mismatch warning on IM-PD1

On Thu, Dec 4, 2025 at 5:42 PM Kuan-Wei Chiu <visitorckw@...il.com> wrote:

> When compiling the device tree for the Integrator/AP with IM-PD1, the
> following warning is observed regarding the display controller node:
>
> arch/arm/boot/dts/arm/integratorap-im-pd1.dts:251.3-14: Warning
> (dma_ranges_format):
> /bus@...00000/bus@...00000/display@...0000:dma-ranges: empty
> "dma-ranges" property but its #address-cells (2) differs from
> /bus@...00000/bus@...00000 (1)
>
> The display node specifies an empty "dma-ranges" property, intended to
> describe a 1:1 identity mapping. However, the node lacks explicit
> "#address-cells" and "#size-cells" properties.

(...)
> +++ b/arch/arm/boot/dts/arm/integratorap-im-pd1.dts
> @@ -248,6 +248,8 @@ display@...0000 {
>                 /* 640x480 16bpp @ 25.175MHz is 36827428 bytes/s */
>                 max-memory-bandwidth = <40000000>;
>                 memory-region = <&impd1_ram>;
> +               #address-cells = <1>;
> +               #size-cells = <1>;
>                 dma-ranges;
>
>                 port@0 {

This is for the *port* node and not for the
stuff mentioned in the commit message, but the port is:

                port@0 {
                        #address-cells = <1>;
                        #size-cells = <0>;

                        clcd_pads_vga_dac: endpoint@0 {
                                reg = <0>;
                                remote-endpoint = <&vga_bridge_in>;
                                arm,pl11x,tft-r0g0b0-pads = <0 8 16>;
                        };
                };

Devoid of any reg, so who cares?

Probably the empty dma-ranges should just be deleted again, it is
pointless for the port.

Yours,
Linus Walleij