Re: [PATCH v4] devicetree: Add generic IOMMU device tree bindings

Will Deacon
2014-07-30T11:04:31Z

Hi all,

On Fri, Jul 04, 2014 at 04:29:17PM +0100, Thierry Reding wrote:
> From: Thierry Reding <treding@nvidia.com>
>
> This commit introduces a generic device tree binding for IOMMU devices.
> Only a very minimal subset is described here, but it is enough to cover
> the requirements of both the Exynos System MMU and Tegra SMMU as
> discussed here:
>
> https://lkml.org/lkml/2014/4/27/346
>
> Signed-off-by: Thierry Reding <treding@nvidia.com>
> ---
> Changes in v4:
> - clarify that disabling an IOMMU DT node may not disable translation
> - be more explicit that examples are only examples
> - add multi-ID master example
>
> Changes in v3:
> - use #iommu-cells instead of #address-cells/#size-cells
> - drop optional iommu-names property
>
> Changes in v2:
> - add notes about "dma-ranges" property (drop note from commit message)
> - document priorities of "iommus" property vs. "dma-ranges" property
> - drop #iommu-cells in favour of #address-cells and #size-cells
> - remove multiple-master device example
>
> Documentation/devicetree/bindings/iommu/iommu.txt | 172 ++++++++++++++++++++++
> 1 file changed, 172 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/iommu/iommu.txt

I'm concerned that this patch hasn't been picked up for 3.17 (I can't see it
in -next). If we want to move the ARM SMMU driver over to this new binding,
we can't keep dragging our feet for much longer as I *really* don't plan to
support two bindings in parallel (one is complicated enough already).

Any chance we can see this merged, please?

Will