Re: [PATCH 02/11] dt-bindings: PCI: qcom: Add iommu properties

From: Manivannan Sadhasivam
Date: Thu Feb 23 2023 - 08:03:12 EST


On Thu, Feb 23, 2023 at 10:37:27AM +0100, Krzysztof Kozlowski wrote:
> On 22/02/2023 16:32, Manivannan Sadhasivam wrote:
> > Most of the PCIe controllers require iommu support to function properly.
> > So let's add them to the binding.
> >
>
> If most of them require iommu, why not adding it as a required property
> to respective (or new) "if:then:" part?
>

Well, I thought about it but then followed the convention of
"dma-coherent" property. I asked this same question while adding that
property but I didn't get a clear answer (or maybe I missed something).

So if you want me to add iommu properties to individual SoCs, then please
explain why the same cannot be done for "dma-coherent" as not all SoCs
support dma coherency for PCIe controllers.

Thanks,
Mani

> Best regards,
> Krzysztof
>