[PATCH V3 2/7] documentation: iommu: Add bindings for msm,iommu-v0 ip
Rob Herring
robh at kernel.org
Tue May 3 19:24:37 PDT 2016
On Mon, May 02, 2016 at 12:24:30AM +0530, Sricharan R wrote:
> The MSM IOMMU is an implementation compatible with the ARM VMSA short
> descriptor page tables. It provides address translation for bus masters outside
> of the CPU, each connected to the IOMMU through a port called micro-TLB.
> Adding the DT bindings for the same.
>
> Signed-off-by: Sricharan R <sricharan at codeaurora.org>
> ---
> .../devicetree/bindings/iommu/msm,iommu-v0.txt | 62 ++++++++++++++++++++++
> 1 file changed, 62 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/iommu/msm,iommu-v0.txt
>
> diff --git a/Documentation/devicetree/bindings/iommu/msm,iommu-v0.txt b/Documentation/devicetree/bindings/iommu/msm,iommu-v0.txt
> new file mode 100644
> index 0000000..63b4f96
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iommu/msm,iommu-v0.txt
> @@ -0,0 +1,62 @@
> +* MSM IOMMU
> +
> +The MSM IOMMU is an implementation compatible with the ARM VMSA short
> +descriptor page tables. It provides address translation for bus masters outside
> +of the CPU, each connected to the IOMMU through a port called micro-TLB.
> +
> +Required Properties:
> +
> + - compatible: Must contain "msm,iommu-v0".
SOC specific compatible strings please.
> + - reg: Base address and size of the IOMMU registers.
> + - interrupts: Specifiers for the MMU fault interrupts. For instances that
> + support secure mode two interrupts must be specified, for non-secure and
> + secure mode, in that order. For instances that don't support secure mode a
> + single interrupt must be specified.
> + - #iommu-cells: The number of cells needed to specify the stream id. This
> + is always 1.
> + - qcom,ncb: The total number of context banks in the IOMMU.
> + - clocks : List of clocks to be used during SMMU register access. See
> + Documentation/devicetree/bindings/clock/clock-bindings.txt
> + for information about the format. For each clock specified
> + here, there must be a corresponding entry in clock-names
> + (see below).
> +
> + - clock-names : List of clock names corresponding to the clocks specified in
> + the "clocks" property (above). See
> + Documentation/devicetree/bindings/clock/clock-bindings.txt
> + for more info.
You must define how many clocks, their order and their names.
> +
> +Each bus master connected to an IOMMU must reference the IOMMU in its device
> +node with the following property:
> +
> + - iommus: A reference to the IOMMU in multiple cells. The first cell is a
> + phandle to the IOMMU and the second cell is the stream id.
> + A single master device can be connected to more than one iommu
> + and multiple contexts in each of the iommu. So multiple entries
> + are required to list all the iommus and the stream ids that the
> + master is connected to.
> +
> +Example: mdp iommu and its bus master
> +
> + mdp_port0: iommu at 7500000 {
> + compatible = "msm,iommu-v0";
> + #iommu-cells = <1>;
> + clock-names =
> + "smmu_pclk",
> + "iommu_clk";
> + clocks =
> + <&mmcc SMMU_AHB_CLK>,
> + <&mmcc MDP_AXI_CLK>;
> + reg = <0x07500000 0x100000>;
> + interrupts =
> + <GIC_SPI 63 0>,
> + <GIC_SPI 64 0>;
> + qcom,ncb = <2>;
> + };
> +
> + mdp: qcom,mdp at 5100000 {
> + compatible = "qcom,mdp";
> + ...
> + iommus = <&mdp_port0 0
> + &mdp_port0 2>;
> + };
> --
> QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation
>
> --
> To unsubscribe from this list: send the line "unsubscribe devicetree" in
> the body of a message to majordomo at vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
More information about the linux-arm-kernel
mailing list