1* ARM SMMUv3 Architecture Implementation 2 3The SMMUv3 architecture is a significant departure from previous 4revisions, replacing the MMIO register interface with in-memory command 5and event queues and adding support for the ATS and PRI components of 6the PCIe specification. 7 8** SMMUv3 required properties: 9 10- compatible : Should include: 11 12 * "arm,smmu-v3" for any SMMUv3 compliant 13 implementation. This entry should be last in the 14 compatible list. 15 16- reg : Base address and size of the SMMU. 17 18- interrupts : Non-secure interrupt list describing the wired 19 interrupt sources corresponding to entries in 20 interrupt-names. If no wired interrupts are 21 present then this property may be omitted. 22 23- interrupt-names : When the interrupts property is present, should 24 include the following: 25 * "eventq" - Event Queue not empty 26 * "priq" - PRI Queue not empty 27 * "cmdq-sync" - CMD_SYNC complete 28 * "gerror" - Global Error activated 29 * "combined" - The combined interrupt is optional, 30 and should only be provided if the 31 hardware supports just a single, 32 combined interrupt line. 33 If provided, then the combined interrupt 34 will be used in preference to any others. 35 36- #iommu-cells : See the generic IOMMU binding described in 37 devicetree/bindings/pci/pci-iommu.txt 38 for details. For SMMUv3, must be 1, with each cell 39 describing a single stream ID. All possible stream 40 IDs which a device may emit must be described. 41 42** SMMUv3 optional properties: 43 44- dma-coherent : Present if DMA operations made by the SMMU (page 45 table walks, stream table accesses etc) are cache 46 coherent with the CPU. 47 48 NOTE: this only applies to the SMMU itself, not 49 masters connected upstream of the SMMU. 50 51- msi-parent : See the generic MSI binding described in 52 devicetree/bindings/interrupt-controller/msi.txt 53 for a description of the msi-parent property. 54 55- hisilicon,broken-prefetch-cmd 56 : Avoid sending CMD_PREFETCH_* commands to the SMMU. 57 58- cavium,cn9900-broken-page1-regspace 59 : Replaces all page 1 offsets used for EVTQ_PROD/CONS, 60 PRIQ_PROD/CONS register access with page 0 offsets. 61 Set for Cavium ThunderX2 silicon that doesn't support 62 SMMU page1 register space. 63 64** Example 65 66 smmu@2b400000 { 67 compatible = "arm,smmu-v3"; 68 reg = <0x0 0x2b400000 0x0 0x20000>; 69 interrupts = <GIC_SPI 74 IRQ_TYPE_EDGE_RISING>, 70 <GIC_SPI 75 IRQ_TYPE_EDGE_RISING>, 71 <GIC_SPI 77 IRQ_TYPE_EDGE_RISING>, 72 <GIC_SPI 79 IRQ_TYPE_EDGE_RISING>; 73 interrupt-names = "eventq", "priq", "cmdq-sync", "gerror"; 74 dma-coherent; 75 #iommu-cells = <1>; 76 msi-parent = <&its 0xff0000>; 77 }; 78