1 # SPDX-License-Identifier: GPL-2.0-only
13 bool "Support for Intel IOMMU using DMA Remapping Devices"
14 depends on PCI_MSI && ACPI && (X86 || IA64)
18 select NEED_DMA_MAP_STATE
25 DMA remapping (DMAR) devices support enables independent address
26 translations for Direct Memory Access (DMA) from devices.
27 These DMA remapping devices are reported via ACPI tables
28 and include PCI device scope covered by these DMA
33 config INTEL_IOMMU_DEBUGFS
34 bool "Export Intel IOMMU internals in Debugfs"
35 depends on IOMMU_DEBUGFS
41 DO NOT ENABLE THIS OPTION UNLESS YOU REALLY KNOW WHAT YOU ARE DOING!!!
43 Expose Intel IOMMU internals in Debugfs.
45 This option is -NOT- intended for production environments, and should
46 only be enabled for debugging Intel IOMMU.
48 config INTEL_IOMMU_SVM
49 bool "Support for Shared Virtual Memory with Intel IOMMU"
54 Shared Virtual Memory (SVM) provides a facility for devices
55 to access DMA resources through process address space by
56 means of a Process Address Space ID (PASID).
58 config INTEL_IOMMU_DEFAULT_ON
59 bool "Enable Intel DMA Remapping Devices by default"
62 Selecting this option will enable a DMAR device at boot time if
63 one is found. If this option is not selected, DMAR support can
64 be enabled by passing intel_iommu=on to the kernel.
66 config INTEL_IOMMU_BROKEN_GFX_WA
67 bool "Workaround broken graphics drivers (going away soon)"
68 depends on BROKEN && X86
70 Current Graphics drivers tend to use physical address
71 for DMA and avoid using DMA APIs. Setting this config
72 option permits the IOMMU driver to set a unity map for
73 all the OS-visible memory. Hence the driver can continue
74 to use physical addresses for DMA, at least until this
75 option is removed in the 2.6.32 kernel.
77 config INTEL_IOMMU_FLOPPY_WA
81 Floppy disk drivers are known to bypass DMA API calls
82 thereby failing to work when IOMMU is enabled. This
83 workaround will setup a 1:1 mapping for the first
84 16MiB to make floppy (an ISA device) work.
86 config INTEL_IOMMU_SCALABLE_MODE_DEFAULT_ON
87 bool "Enable Intel IOMMU scalable mode by default"
90 Selecting this option will enable by default the scalable mode if
91 hardware presents the capability. The scalable mode is defined in
92 VT-d 3.0. The scalable mode capability could be checked by reading
93 /sys/devices/virtual/iommu/dmar*/intel-iommu/ecap. If this option
94 is not selected, scalable mode support could also be enabled by
95 passing intel_iommu=sm_on to the kernel. If not sure, please use
98 config INTEL_IOMMU_PERF_EVENTS
100 bool "Intel IOMMU performance events"
101 depends on INTEL_IOMMU && PERF_EVENTS
103 Selecting this option will enable the performance monitoring
104 infrastructure in the Intel IOMMU. It collects information about
105 key events occurring during operation of the remapping hardware,
106 to aid performance tuning and debug. These are available on modern
107 processors which support Intel VT-d 4.0 and later.