Re: [PATCH v3 2/8] media: dt-bindings: Add qcs6490-rb3gen2-vision-mezzanine

[Dmitry Baryshkov]

On Fri, Oct 11, 2024 at 04:25:15PM +0100, Bryan O'Donoghue wrote:
> On 11/10/2024 15:50, Krzysztof Kozlowski wrote:
> > On Fri, Oct 11, 2024 at 07:39:26PM +0530, Vikram Sharma wrote:
> > > The qcs6490-rb3gen2-vision-mezzanine is a mezz on top of the
> > > qcs6490-rb3gen2 core kit. The vision mezzanine includes the
> > > IMX577 camera sensor.
> > > 
> > > Signed-off-by: Vikram Sharma <quic_vikramsa@xxxxxxxxxxx>
> > > ---
> > >   Documentation/devicetree/bindings/arm/qcom.yaml | 1 +
> > >   1 file changed, 1 insertion(+)
> > > 
> > > diff --git a/Documentation/devicetree/bindings/arm/qcom.yaml b/Documentation/devicetree/bindings/arm/qcom.yaml
> > > index 5de6290cd063..f00851f30d3e 100644
> > > --- a/Documentation/devicetree/bindings/arm/qcom.yaml
> > > +++ b/Documentation/devicetree/bindings/arm/qcom.yaml
> > > @@ -390,6 +390,7 @@ properties:
> > >                 - fairphone,fp5
> > >                 - qcom,qcm6490-idp
> > >                 - qcom,qcs6490-rb3gen2
> > > +              - qcom,qcs6490-rb3gen2-vision-mezzanine
> > 
> > Shouldn't this be an overlay?
> > 
> > Best regards,
> > Krzysztof
> > 
> 
> Because of broken bootloaders which don't do overlays, we've been adding
> additional dts instead.
> 
> For preference everybody would run u-boot, grub or another reasonable
> bootloader that can apply an overlay.
> 
> Last time I checked there was no support for dtbo upstream in the kernel
> itself.

See arch/arm64/boot/dts/qcom/Makefile:

sm8650-hdk-display-card-dtbs    := sm8650-hdk.dtb sm8650-hdk-display-card.dtbo

dtb-$(CONFIG_ARCH_QCOM) += sm8650-hdk-display-card.dtb

> 
> greps
> 
> grep -r of_overlay_fdt_apply *
> 
> Hmm, does this do what I think it does ? Its news to me if there's a way to
> do this in the kernel now TBH.
> 
> Otherwise the sad situation with shipping bootloaders means we are pretty
> much stuck with the one blob which we can't apply an update to.
> 
-- 
With best wishes
Dmitry