Re: [PATCH v2 2/3] arm64: dts: rockchip: Fix vdec register blocks order on RK3576

From: Nicolas Dufresne

Date: Tue Feb 24 2026 - 08:20:55 EST


Hi,

Le mardi 24 février 2026 à 08:22 +0100, Krzysztof Kozlowski a écrit :
> On Mon, Feb 23, 2026 at 09:49:50PM +0200, Cristian Ciocaltea wrote:
> > When building device trees for the RK3576 based boards, DTC shows the
> > following complaint:
> >
> >   rk3576.dtsi:1282.30-1304.5: Warning (simple_bus_reg): /soc/video-codec@27b00000: simple-bus unit address format error, expected "27b00100"
>
> So you need to fix the unit address. This is what the warning tells you.

The unit address is where the register range starts. Picking a random point
inside the range is just bad idea. For anyone that uses spec to develop these
drivers and device tree, its just plain difficult and error prone.

>
> >
> > Provide the register blocks in the expected address-based order.
> >
> > Fixes: da0de806d8b4 ("arm64: dts: rockchip: Add the vdpu383 Video Decoder on rk3576")
> > Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@xxxxxxxxxxxxx>
> > ---
> >  arch/arm64/boot/dts/rockchip/rk3576.dtsi | 6 +++---
> >  1 file changed, 3 insertions(+), 3 deletions(-)
> >
> > diff --git a/arch/arm64/boot/dts/rockchip/rk3576.dtsi b/arch/arm64/boot/dts/rockchip/rk3576.dtsi
> > index 49ccdf12ef7e..45eb0d053a6f 100644
> > --- a/arch/arm64/boot/dts/rockchip/rk3576.dtsi
> > +++ b/arch/arm64/boot/dts/rockchip/rk3576.dtsi
> > @@ -1281,10 +1281,10 @@ gpu: gpu@27800000 {
> >  
> >   vdec: video-codec@27b00000 {
> >   compatible = "rockchip,rk3576-vdec";
> > - reg = <0x0 0x27b00100 0x0 0x500>,
> > -       <0x0 0x27b00000 0x0 0x100>,
> > + reg = <0x0 0x27b00000 0x0 0x100>,
> > +       <0x0 0x27b00100 0x0 0x500>,
> >         <0x0 0x27b00600 0x0 0x100>;
>
> The main block, so probably the lowest address as in unit address,
> should be used, but this ship has sailed. You shipped this DTS, because
> the order of items is FIXED. Your binding change is clearly incorrect
> and ABI break without explanation and without reason, so you cannot use
> such as an argument here.

Its not released yet.


> You cannot change it without impact, so just fix the unit address.

I completely disagree with that.

Nicolas

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