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

Manivannan Sadhasivam posted 11 patches 2 years, 6 months ago
There is a newer version of this series
[PATCH 02/11] dt-bindings: PCI: qcom: Add iommu properties
Posted by Manivannan Sadhasivam 2 years, 6 months ago
Most of the PCIe controllers require iommu support to function properly.
So let's add them to the binding.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
 Documentation/devicetree/bindings/pci/qcom,pcie.yaml | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/Documentation/devicetree/bindings/pci/qcom,pcie.yaml b/Documentation/devicetree/bindings/pci/qcom,pcie.yaml
index a3639920fcbb..f48d0792aa57 100644
--- a/Documentation/devicetree/bindings/pci/qcom,pcie.yaml
+++ b/Documentation/devicetree/bindings/pci/qcom,pcie.yaml
@@ -64,6 +64,11 @@ properties:
 
   dma-coherent: true
 
+  iommus:
+    maxItems: 1
+
+  iommu-map: true
+
   interconnects:
     maxItems: 2
 
-- 
2.25.1
Re: [PATCH 02/11] dt-bindings: PCI: qcom: Add iommu properties
Posted by Krzysztof Kozlowski 2 years, 6 months ago
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?

Best regards,
Krzysztof
Re: [PATCH 02/11] dt-bindings: PCI: qcom: Add iommu properties
Posted by Manivannan Sadhasivam 2 years, 6 months ago
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
>