On Mon, Dec 05, 2022 at 01:27:34PM +0100, Johan Hovold wrote: > On Mon, Dec 05, 2022 at 05:50:18PM +0530, Manivannan Sadhasivam wrote: > > On Mon, Dec 05, 2022 at 01:07:16PM +0100, Johan Hovold wrote: > > > On Mon, Dec 05, 2022 at 05:29:06PM +0530, Manivannan Sadhasivam wrote: > > > > On Mon, Dec 05, 2022 at 11:08:36AM +0100, Johan Hovold wrote: > > > > > UFS controllers may be cache coherent and must be marked as such in the > > > > > devicetree to avoid data corruption. > > > > > > > > > > This is specifically needed on recent Qualcomm platforms like SC8280XP. > > > > > > > > > > Signed-off-by: Johan Hovold <johan+linaro@xxxxxxxxxx> > > > > > --- > > > > > Documentation/devicetree/bindings/ufs/qcom,ufs.yaml | 2 ++ > > > > > 1 file changed, 2 insertions(+) > > > > > > > > > > diff --git a/Documentation/devicetree/bindings/ufs/qcom,ufs.yaml b/Documentation/devicetree/bindings/ufs/qcom,ufs.yaml > > > > > index f2d6298d926c..1f1d286749c0 100644 > > > > > --- a/Documentation/devicetree/bindings/ufs/qcom,ufs.yaml > > > > > +++ b/Documentation/devicetree/bindings/ufs/qcom,ufs.yaml > > > > > @@ -44,6 +44,8 @@ properties: > > > > > minItems: 8 > > > > > maxItems: 11 > > > > > > > > > > + dma-coherent: true > > > > > + > > > > > > > > This property is not applicable to all SoCs. So setting true here will make it > > > > valid for all. > > > > > > Yes, it would be a valid, but it will only be added to the DTs of SoCs > > > that actually require it. No need to re-encode the dtsi in the binding. > > > > > > > But if you make a property valid in the binding then it implies that anyone > > could add it to DTS which is wrong. You should make this property valid for > > SoCs that actually support it. > > No, it's not wrong. > > Note that the binding only requires 'compatible' and 'regs', all other > properties are optional, and you could, for example, add a > 'reset' property to a node for a device which does not have a reset > without the DT validation failing. > Then what is the point of devicetree validation using bindings? There is also a comment from Krzysztof: https://lkml.org/lkml/2022/11/24/390 Thanks, Mani > It's the devicetree which is supposed to describe hardware, you don't > have to encode it also in the binding. > > Johan -- மணிவண்ணன் சதாசிவம்