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Diffstat (limited to 'Documentation/devicetree/bindings/pci/pci-iommu.txt')
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1 files changed, 0 insertions, 171 deletions
diff --git a/Documentation/devicetree/bindings/pci/pci-iommu.txt b/Documentation/devicetree/bindings/pci/pci-iommu.txt deleted file mode 100644 index 0def586fdcdf..000000000000 --- a/Documentation/devicetree/bindings/pci/pci-iommu.txt +++ /dev/null @@ -1,171 +0,0 @@ -This document describes the generic device tree binding for describing the -relationship between PCI(e) devices and IOMMU(s). - -Each PCI(e) device under a root complex is uniquely identified by its Requester -ID (AKA RID). A Requester ID is a triplet of a Bus number, Device number, and -Function number. - -For the purpose of this document, when treated as a numeric value, a RID is -formatted such that: - -* Bits [15:8] are the Bus number. -* Bits [7:3] are the Device number. -* Bits [2:0] are the Function number. -* Any other bits required for padding must be zero. - -IOMMUs may distinguish PCI devices through sideband data derived from the -Requester ID. While a given PCI device can only master through one IOMMU, a -root complex may split masters across a set of IOMMUs (e.g. with one IOMMU per -bus). - -The generic 'iommus' property is insufficient to describe this relationship, -and a mechanism is required to map from a PCI device to its IOMMU and sideband -data. - -For generic IOMMU bindings, see -Documentation/devicetree/bindings/iommu/iommu.txt. - - -PCI root complex -================ - -Optional properties -------------------- - -- iommu-map: Maps a Requester ID to an IOMMU and associated IOMMU specifier - data. - - The property is an arbitrary number of tuples of - (rid-base,iommu,iommu-base,length). - - Any RID r in the interval [rid-base, rid-base + length) is associated with - the listed IOMMU, with the IOMMU specifier (r - rid-base + iommu-base). - -- iommu-map-mask: A mask to be applied to each Requester ID prior to being - mapped to an IOMMU specifier per the iommu-map property. - - -Example (1) -=========== - -/ { - #address-cells = <1>; - #size-cells = <1>; - - iommu: iommu@a { - reg = <0xa 0x1>; - compatible = "vendor,some-iommu"; - #iommu-cells = <1>; - }; - - pci: pci@f { - reg = <0xf 0x1>; - compatible = "vendor,pcie-root-complex"; - device_type = "pci"; - - /* - * The sideband data provided to the IOMMU is the RID, - * identity-mapped. - */ - iommu-map = <0x0 &iommu 0x0 0x10000>; - }; -}; - - -Example (2) -=========== - -/ { - #address-cells = <1>; - #size-cells = <1>; - - iommu: iommu@a { - reg = <0xa 0x1>; - compatible = "vendor,some-iommu"; - #iommu-cells = <1>; - }; - - pci: pci@f { - reg = <0xf 0x1>; - compatible = "vendor,pcie-root-complex"; - device_type = "pci"; - - /* - * The sideband data provided to the IOMMU is the RID with the - * function bits masked out. - */ - iommu-map = <0x0 &iommu 0x0 0x10000>; - iommu-map-mask = <0xfff8>; - }; -}; - - -Example (3) -=========== - -/ { - #address-cells = <1>; - #size-cells = <1>; - - iommu: iommu@a { - reg = <0xa 0x1>; - compatible = "vendor,some-iommu"; - #iommu-cells = <1>; - }; - - pci: pci@f { - reg = <0xf 0x1>; - compatible = "vendor,pcie-root-complex"; - device_type = "pci"; - - /* - * The sideband data provided to the IOMMU is the RID, - * but the high bits of the bus number are flipped. - */ - iommu-map = <0x0000 &iommu 0x8000 0x8000>, - <0x8000 &iommu 0x0000 0x8000>; - }; -}; - - -Example (4) -=========== - -/ { - #address-cells = <1>; - #size-cells = <1>; - - iommu_a: iommu@a { - reg = <0xa 0x1>; - compatible = "vendor,some-iommu"; - #iommu-cells = <1>; - }; - - iommu_b: iommu@b { - reg = <0xb 0x1>; - compatible = "vendor,some-iommu"; - #iommu-cells = <1>; - }; - - iommu_c: iommu@c { - reg = <0xc 0x1>; - compatible = "vendor,some-iommu"; - #iommu-cells = <1>; - }; - - pci: pci@f { - reg = <0xf 0x1>; - compatible = "vendor,pcie-root-complex"; - device_type = "pci"; - - /* - * Devices with bus number 0-127 are mastered via IOMMU - * a, with sideband data being RID[14:0]. - * Devices with bus number 128-255 are mastered via - * IOMMU b, with sideband data being RID[14:0]. - * No devices master via IOMMU c. - */ - iommu-map = <0x0000 &iommu_a 0x0000 0x8000>, - <0x8000 &iommu_b 0x0000 0x8000>; - }; -}; |