Re: [PATCH 1/2] dt-bindings: dma: fsl,edma: add iommu-map property

[Frank Li]

On Wed, Sep 16, 2026 at 11:55:25PM +0800, Peng Fan (OSS) wrote:
> From: Peng Fan <peng.fan@xxxxxxx>
>
> Add the iommu-map property to the fsl,edma binding to allow per-channel
> IOMMU stream ID mapping. This enables IOMMU translation for individual
> eDMA channels, where paired channels can share the same stream ID and
> channels without an entry operate in bypass mode.
>
> Also add a new example using fsl,imx95-edma5 that demonstrates the
> iommu-map usage with per-channel mappings.
>
> Assisted-by: Claude:claude-opus-4-6
> Signed-off-by: Peng Fan <peng.fan@xxxxxxx>
> ---

Reviewed-by: Frank Li <Frank.Li@xxxxxxx>

>  .../devicetree/bindings/dma/fsl,edma.yaml          | 89 ++++++++++++++++++++++
>  1 file changed, 89 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/dma/fsl,edma.yaml b/Documentation/devicetree/bindings/dma/fsl,edma.yaml
> index f609038e35ae1..cb8c650a5bb90 100644
> --- a/Documentation/devicetree/bindings/dma/fsl,edma.yaml
> +++ b/Documentation/devicetree/bindings/dma/fsl,edma.yaml
> @@ -104,6 +104,15 @@ properties:
>        Bit semantics: 0 means channel available, 1 means channel unavailable
>      default: 0
>
> +  iommu-map:
> +    description:
> +      Maps DMA channel numbers to IOMMU stream IDs. Each entry maps one
> +      or more channels to a contiguous range of stream IDs. Paired channels
> +      may share the same stream ID. Channels without an entry operate in
> +      bypass mode.
> +    minItems: 1
> +    maxItems: 64
> +
>  required:
>    - "#dma-cells"
>    - compatible
> @@ -351,3 +360,83 @@ examples:
>                        <&pd IMX_SC_R_DMA_3_CH6>,
>                        <&pd IMX_SC_R_DMA_3_CH7>;
>      };
> +
> +  - |
> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
> +
> +    dma-controller@42000000 {
> +      compatible = "fsl,imx95-edma5";
> +      reg = <0x42000000 0x210000>;
> +      #dma-cells = <3>;
> +      dma-channels = <64>;
> +      interrupts = <GIC_SPI 128 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 128 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 130 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 131 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 132 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 133 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 134 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 135 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 136 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 137 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 138 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 139 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 140 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 141 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 142 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 143 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 144 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 145 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 146 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 147 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 148 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 148 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 149 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 149 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 150 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 150 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 151 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 151 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 152 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 152 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 153 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 153 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 154 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 154 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 155 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 155 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 156 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 156 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 157 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 157 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 158 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 158 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 159 IRQ_TYPE_LEVEL_HIGH>,
> +                   <GIC_SPI 159 IRQ_TYPE_LEVEL_HIGH>;
> +      clocks = <&clk 0>;
> +      clock-names = "dma";
> +      /*
> +       * Per-channel IOMMU mapping. Each channel
> +       * occupies one entry; paired channels share
> +       * the same SID. Channels without an entry
> +       * operate in bypass mode.
> +       */
> +      iommu-map = <2 &smmu 0x30 1>,
> +                  <3 &smmu 0x30 1>,
> +                  <4 &smmu 0x31 1>,
> +                  <5 &smmu 0x31 1>,
> +                  <6 &smmu 0x32 1>,
> +                  <7 &smmu 0x32 1>,
> +                  <8 &smmu 0x33 1>,
> +                  <9 &smmu 0x33 1>,
> +                  <10 &smmu 0x34 1>,
> +                  <11 &smmu 0x34 1>,
> +                  <12 &smmu 0x35 1>,
> +                  <13 &smmu 0x35 1>,
> +                  <14 &smmu 0x36 1>,
> +                  <15 &smmu 0x36 1>,
> +                  <16 &smmu 0x37 1>,
> +                  <17 &smmu 0x37 1>,
> +                  <18 &smmu 0x38 1>,
> +                  <19 &smmu 0x38 1>;
> +    };
>
> --
> 2.34.1
>