Re: [PATCH 2/8] dt-bindings: document PASID property for IOMMU masters

Auger Eric
2019-07-08T07:58:38Z

Hi Jean,

On 6/10/19 8:47 PM, Jean-Philippe Brucker wrote:
> On Arm systems, some platform devices behind an SMMU may support the PASID
> feature, which offers multiple address space. Let the firmware tell us
> when a device supports PASID.
>
> Reviewed-by: Rob Herring <robh@kernel.org>
> Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
> ---
> Previous discussion on this patch last year:
> https://patchwork.ozlabs.org/patch/872275/
> I split PASID and stall definitions, keeping only PASID here.
> ---
> Documentation/devicetree/bindings/iommu/iommu.txt | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/iommu/iommu.txt b/Documentation/devicetree/bindings/iommu/iommu.txt
> index 5a8b4624defc..3c36334e4f94 100644
> --- a/Documentation/devicetree/bindings/iommu/iommu.txt
> +++ b/Documentation/devicetree/bindings/iommu/iommu.txt
> @@ -86,6 +86,12 @@ have a means to turn off translation. But it is invalid in such cases to
> disable the IOMMU's device tree node in the first place because it would
> prevent any driver from properly setting up the translations.
>
> +Optional properties:
> +--------------------
> +- pasid-num-bits: Some masters support multiple address spaces for DMA, by
> + tagging DMA transactions with an address space identifier. By default,
> + this is 0, which means that the device only has one address space.
> +
Reviewed-by: Eric Auger <eric.auger@redhat.com>

Thanks

Eric
>
> Notes:
> ======
>