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

Kuan-Wei Chiu posted 1 patch 2 months ago
There is a newer version of this series
arch/arm/boot/dts/arm/integratorap-im-pd1.dts | 2 ++
1 file changed, 2 insertions(+)
[PATCH] ARM: dts: integrator: Fix DMA ranges mismatch warning on IM-PD1
Posted by Kuan-Wei Chiu 2 months ago
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@c0000000/bus@c0000000/display@1000000:dma-ranges: empty
"dma-ranges" property but its #address-cells (2) differs from
/bus@c0000000/bus@c0000000 (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. In this case, the device
tree compiler defaults the address cells to 2 (64-bit), which conflicts
with the parent bus configuration (32-bit, 1 cell).

Fix this by explicitly defining "#address-cells" and "#size-cells" as
1. This matches the 32-bit architecture of the Integrator platform and
ensures the address translation range is correctly parsed by the
compiler.

Fixes: 7bea67a99430 ("ARM: dts: integrator: Fix DMA ranges")
Cc: stable@vger.kernel.org
Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com>
---
 arch/arm/boot/dts/arm/integratorap-im-pd1.dts | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/arm/boot/dts/arm/integratorap-im-pd1.dts b/arch/arm/boot/dts/arm/integratorap-im-pd1.dts
index db13e09f2fab..6d90d9a42dc9 100644
--- a/arch/arm/boot/dts/arm/integratorap-im-pd1.dts
+++ b/arch/arm/boot/dts/arm/integratorap-im-pd1.dts
@@ -248,6 +248,8 @@ display@1000000 {
 		/* 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 {
-- 
2.52.0.177.g9f829587af-goog
Re: [PATCH] ARM: dts: integrator: Fix DMA ranges mismatch warning on IM-PD1
Posted by Linus Walleij 1 month, 2 weeks ago
On Thu, Dec 4, 2025 at 5:42 PM Kuan-Wei Chiu <visitorckw@gmail.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@c0000000/bus@c0000000/display@1000000:dma-ranges: empty
> "dma-ranges" property but its #address-cells (2) differs from
> /bus@c0000000/bus@c0000000 (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@1000000 {
>                 /* 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
Re: [PATCH] ARM: dts: integrator: Fix DMA ranges mismatch warning on IM-PD1
Posted by Rob Herring 2 months ago
On Thu, 04 Dec 2025 16:42:28 +0000, Kuan-Wei Chiu 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@c0000000/bus@c0000000/display@1000000:dma-ranges: empty
> "dma-ranges" property but its #address-cells (2) differs from
> /bus@c0000000/bus@c0000000 (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. In this case, the device
> tree compiler defaults the address cells to 2 (64-bit), which conflicts
> with the parent bus configuration (32-bit, 1 cell).
> 
> Fix this by explicitly defining "#address-cells" and "#size-cells" as
> 1. This matches the 32-bit architecture of the Integrator platform and
> ensures the address translation range is correctly parsed by the
> compiler.
> 
> Fixes: 7bea67a99430 ("ARM: dts: integrator: Fix DMA ranges")
> Cc: stable@vger.kernel.org
> Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com>
> ---
>  arch/arm/boot/dts/arm/integratorap-im-pd1.dts | 2 ++
>  1 file changed, 2 insertions(+)
> 


My bot found new DTB warnings on the .dts files added or changed in this
series.

Some warnings may be from an existing SoC .dtsi. Or perhaps the warnings
are fixed by another series. Ultimately, it is up to the platform
maintainer whether these warnings are acceptable or not. No need to reply
unless the platform maintainer has comments.

If you already ran DT checks and didn't see these error(s), then
make sure dt-schema is up to date:

  pip3 install dtschema --upgrade


This patch series was applied (using b4) to base:
 Base: attempting to guess base-commit...
 Base: tags/v6.18-rc6-2004-g29bce9c8b41d (exact match)
 Base: tags/v6.18-rc6-2004-g29bce9c8b41d (use --merge-base to override)

If this is not the correct base, please add 'base-commit' tag
(or use b4 which does this automatically)

New warnings running 'make CHECK_DTBS=y for arch/arm/boot/dts/arm/' for 20251204164228.113587-1-visitorckw@gmail.com:

arch/arm/boot/dts/arm/integratorap-im-pd1.dtb: display@1000000 (arm,pl110): '#address-cells', '#size-cells', 'dma-ranges', 'port@0' do not match any of the regexes: '^pinctrl-[0-9]+$'
	from schema $id: http://devicetree.org/schemas/display/arm,pl11x.yaml