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Diffstat (limited to 'Documentation/devicetree/bindings/iommu/msm,iommu-v0.txt')
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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 000000000000..20236385f26e --- /dev/null +++ b/Documentation/devicetree/bindings/iommu/msm,iommu-v0.txt @@ -0,0 +1,64 @@ +* QCOM 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 "qcom,apq8064-iommu". + - 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). + Should be "smmu_pclk" for specifying the interface clock + required for iommu's register accesses. + Should be "smmu_clk" for specifying the functional clock + required by iommu for bus accesses. + +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@7500000 { + compatible = "qcom,apq8064-iommu"; + #iommu-cells = <1>; + clock-names = + "smmu_pclk", + "smmu_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@5100000 { + compatible = "qcom,mdp"; + ... + iommus = <&mdp_port0 0 + &mdp_port0 2>; + }; |