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authorLinus Torvalds <torvalds@linux-foundation.org>2015-06-23 18:27:19 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2015-06-23 18:27:19 -0700
commit6eae81a5e2d6646a61146501fd3032a340863c1d (patch)
treec1c8a5fd7930f756d4d124870e0076903e3b4ba0 /Documentation
parent54245ed870c8cf9ff87fdf78955ffbc93b261e9f (diff)
parent5ffde2f67181195d457b95df44b8f88e8d969d89 (diff)
Merge tag 'iommu-updates-v4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull IOMMU updates from Joerg Roedel: "This time with bigger changes than usual: - A new IOMMU driver for the ARM SMMUv3. This IOMMU is pretty different from SMMUv1 and v2 in that it is configured through in-memory structures and not through the MMIO register region. The ARM SMMUv3 also supports IO demand paging for PCI devices with PRI/PASID capabilities, but this is not implemented in the driver yet. - Lots of cleanups and device-tree support for the Exynos IOMMU driver. This is part of the effort to bring Exynos DRM support upstream. - Introduction of default domains into the IOMMU core code. The rationale behind this is to move functionalily out of the IOMMU drivers to common code to get to a unified behavior between different drivers. The patches here introduce a default domain for iommu-groups (isolation groups). A device will now always be attached to a domain, either the default domain or another domain handled by the device driver. The IOMMU drivers have to be modified to make use of that feature. So long the AMD IOMMU driver is converted, with others to follow. - Patches for the Intel VT-d drvier to fix DMAR faults that happen when a kdump kernel boots. When the kdump kernel boots it re-initializes the IOMMU hardware, which destroys all mappings from the crashed kernel. As this happens before the endpoint devices are re-initialized, any in-flight DMA causes a DMAR fault. These faults cause PCI master aborts, which some devices can't handle properly and go into an undefined state, so that the device driver in the kdump kernel fails to initialize them and the dump fails. This is now fixed by copying over the mapping structures (only context tables and interrupt remapping tables) from the old kernel and keep the old mappings in place until the device driver of the new kernel takes over. This emulates the the behavior without an IOMMU to the best degree possible. - A couple of other small fixes and cleanups" * tag 'iommu-updates-v4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (69 commits) iommu/amd: Handle large pages correctly in free_pagetable iommu/vt-d: Don't disable IR when it was previously enabled iommu/vt-d: Make sure copied over IR entries are not reused iommu/vt-d: Copy IR table from old kernel when in kdump mode iommu/vt-d: Set IRTA in intel_setup_irq_remapping iommu/vt-d: Disable IRQ remapping in intel_prepare_irq_remapping iommu/vt-d: Move QI initializationt to intel_setup_irq_remapping iommu/vt-d: Move EIM detection to intel_prepare_irq_remapping iommu/vt-d: Enable Translation only if it was previously disabled iommu/vt-d: Don't disable translation prior to OS handover iommu/vt-d: Don't copy translation tables if RTT bit needs to be changed iommu/vt-d: Don't do early domain assignment if kdump kernel iommu/vt-d: Allocate si_domain in init_dmars() iommu/vt-d: Mark copied context entries iommu/vt-d: Do not re-use domain-ids from the old kernel iommu/vt-d: Copy translation tables from old kernel iommu/vt-d: Detect pre enabled translation iommu/vt-d: Make root entry visible for hardware right after allocation iommu/vt-d: Init QI before root entry is allocated iommu/vt-d: Cleanup log messages ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/devicetree/bindings/iommu/arm,smmu-v3.txt37
1 files changed, 37 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/iommu/arm,smmu-v3.txt b/Documentation/devicetree/bindings/iommu/arm,smmu-v3.txt
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+* ARM SMMUv3 Architecture Implementation
+
+The SMMUv3 architecture is a significant deparature from previous
+revisions, replacing the MMIO register interface with in-memory command
+and event queues and adding support for the ATS and PRI components of
+the PCIe specification.
+
+** SMMUv3 required properties:
+
+- compatible : Should include:
+
+ * "arm,smmu-v3" for any SMMUv3 compliant
+ implementation. This entry should be last in the
+ compatible list.
+
+- reg : Base address and size of the SMMU.
+
+- interrupts : Non-secure interrupt list describing the wired
+ interrupt sources corresponding to entries in
+ interrupt-names. If no wired interrupts are
+ present then this property may be omitted.
+
+- interrupt-names : When the interrupts property is present, should
+ include the following:
+ * "eventq" - Event Queue not empty
+ * "priq" - PRI Queue not empty
+ * "cmdq-sync" - CMD_SYNC complete
+ * "gerror" - Global Error activated
+
+** SMMUv3 optional properties:
+
+- dma-coherent : Present if DMA operations made by the SMMU (page
+ table walks, stream table accesses etc) are cache
+ coherent with the CPU.
+
+ NOTE: this only applies to the SMMU itself, not
+ masters connected upstream of the SMMU.