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authorLinus Torvalds <torvalds@linux-foundation.org>2016-10-11 12:52:41 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2016-10-11 12:52:41 -0700
commit56e520c7a0a490b63b042b047ec9659fc08762a4 (patch)
treeb20296f4b088d81aba3c41174d52afa209afff9b /Documentation/devicetree/bindings/pci
parentd09ba13110e303d7baa29d170da94cd24f7662b2 (diff)
parent13a08259187c5cd3f63d98efa159ab42976d85a4 (diff)
Merge tag 'iommu-updates-v4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull IOMMU updates from Joerg Roedel: - support for interrupt virtualization in the AMD IOMMU driver. These patches were shared with the KVM tree and are already merged through that tree. - generic DT-binding support for the ARM-SMMU driver. With this the driver now makes use of the generic DMA-API code. This also required some changes outside of the IOMMU code, but these are acked by the respective maintainers. - more cleanups and fixes all over the place. * tag 'iommu-updates-v4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (40 commits) iommu/amd: No need to wait iommu completion if no dte irq entry change iommu/amd: Free domain id when free a domain of struct dma_ops_domain iommu/amd: Use standard bitmap operation to set bitmap iommu/amd: Clean up the cmpxchg64 invocation iommu/io-pgtable-arm: Check for v7s-incapable systems iommu/dma: Avoid PCI host bridge windows iommu/dma: Add support for mapping MSIs iommu/arm-smmu: Set domain geometry iommu/arm-smmu: Wire up generic configuration support Docs: dt: document ARM SMMU generic binding usage iommu/arm-smmu: Convert to iommu_fwspec iommu/arm-smmu: Intelligent SMR allocation iommu/arm-smmu: Add a stream map entry iterator iommu/arm-smmu: Streamline SMMU data lookups iommu/arm-smmu: Refactor mmu-masters handling iommu/arm-smmu: Keep track of S2CR state iommu/arm-smmu: Consolidate stream map entry state iommu/arm-smmu: Handle stream IDs more dynamically iommu/arm-smmu: Set PRIVCFG in stage 1 STEs iommu/arm-smmu: Support non-PCI devices with SMMUv3 ...
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+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>;
+ };
+};