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Date:   Tue, 1 Mar 2022 18:12:06 +0000
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Subject: Re: [PATCH v4 1/9] dt-bindings: host1x: Add iommu-map property
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To:     cyndis@kapsi.fi, thierry.reding@gmail.com, jonathanh@nvidia.com,
        joro@8bytes.org, will@kernel.org, robh+dt@kernel.org,
        krzysztof.kozlowski@canonical.com
Cc:     linux-tegra@vger.kernel.org, dri-devel@lists.freedesktop.org,
        iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org,
        devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        Mikko Perttunen <mperttunen@nvidia.com>
References: <20220301161455.4037062-1-cyndis@kapsi.fi>
 <20220301161455.4037062-2-cyndis@kapsi.fi>
From:   Robin Murphy <robin.murphy@arm.com>
In-Reply-To: <20220301161455.4037062-2-cyndis@kapsi.fi>
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On 2022-03-01 16:14, cyndis@kapsi.fi wrote:
> From: Mikko Perttunen <mperttunen@nvidia.com>
> 
> Add schema information for specifying context stream IDs. This uses
> the standard iommu-map property.
> 
> Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
> ---
> v3:
> * New patch
> v4:
> * Remove memory-contexts subnode.
> ---
>   .../bindings/display/tegra/nvidia,tegra20-host1x.yaml        | 5 +++++
>   1 file changed, 5 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-host1x.yaml b/Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-host1x.yaml
> index 4fd513efb0f7..0adeb03b9e3a 100644
> --- a/Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-host1x.yaml
> +++ b/Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-host1x.yaml
> @@ -144,6 +144,11 @@ allOf:
>           reset-names:
>             maxItems: 1
>   
> +        iommu-map:
> +          description: Specification of stream IDs available for memory context device
> +            use. Should be a mapping of IDs 0..n to IOMMU entries corresponding to

Nit: maybe "context IDs 0..n" for maximum possible clarity?

Either way, though, I'm happy that if the simplest and most 
straightforward approach works, then it's the best choice.

Reviewed-by: Robin Murphy <robin.murphy@arm.com>

Cheers,
Robin.

> +            usable stream IDs.
> +
>         required:
>           - reg-names
>