[PATCH v3 1/3] dt-bindings: mtd: cdns,hp-nfc: Add iommu property

[Krzysztof Kozlowski]

On Wed, Oct 15, 2025 at 08:13:37AM +0800, Khairul Anuar Romli wrote:
> Agilex5 integrates an ARM SMMU (System Memory Management Unit) with
> Translation Buffer Units (TBUs) assigned to various peripherals,
> including the NAND controller.
> 
> The Cadence HP NAND controller ("cdns,hp-nfc") on Agilex5 is behind a
> TBU connected to the system's SMMUv3. To support this, the controller
> requires an `iommus` property in the device tree to properly configure
> address translation through the IOMMU framework.
> 
> Adding the `iommus` property to the binding schema allows the OS
> to associate the NAND controller with its corresponding SMMU stream ID.
> This enables:
> - DMA address translation between the controller and system memory
> - Memory protection for NAND operations
> - Proper functioning of the IOMMU framework in secure or virtualized
>   environments
> 
> This change documents the IOMMU integration for the NAND controller
> on platforms like Agilex5 where such hardware is present.
> 
> Signed-off-by: Adrian Ng Ho Yin <adrianhoyin.ng at altera.com>
> Signed-off-by: Khairul Anuar Romli <khairul.anuar.romli at altera.com>
> ---
> Changes in v3:
> 	- Refined commit messages with detailed hardware descriptions.
> 	- Remove redundant commit message and add the hardware used for
> 	  iommu.
> Changes in v2:
> 	- Updated the commit message to clarify the need for the changes
> 	  and the hardware used of this changes.
> ---
>  Documentation/devicetree/bindings/mtd/cdns,hp-nfc.yaml | 3 +++
>  1 file changed, 3 insertions(+)

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski at linaro.org>

Best regards,
Krzysztof