Kconfig

  1# SPDX-License-Identifier: GPL-2.0-only
  2# Intel IOMMU support
  3config DMAR_TABLE
  4	bool
  5
  6config DMAR_PERF
  7	bool
  8
  9config DMAR_DEBUG
 10	bool
 11
 12config INTEL_IOMMU
 13	bool "Support for Intel IOMMU using DMA Remapping Devices"
 14	depends on PCI_MSI && ACPI && X86
 15	select IOMMU_API
 16	select GENERIC_PT
 17	select IOMMU_PT
 18	select IOMMU_PT_X86_64
 19	select IOMMU_PT_VTDSS
 20	select IOMMU_IOVA
 21	select IOMMU_IOPF
 22	select IOMMUFD_DRIVER if IOMMUFD
 23	select NEED_DMA_MAP_STATE
 24	select DMAR_TABLE
 25	select SWIOTLB
 26	select PCI_ATS
 27	select PCI_PRI
 28	select PCI_PASID
 29	help
 30	  DMA remapping (DMAR) devices support enables independent address
 31	  translations for Direct Memory Access (DMA) from devices.
 32	  These DMA remapping devices are reported via ACPI tables
 33	  and include PCI device scope covered by these DMA
 34	  remapping devices.
 35
 36if INTEL_IOMMU
 37
 38config INTEL_IOMMU_DEBUGFS
 39	bool "Export Intel IOMMU internals in Debugfs"
 40	depends on IOMMU_DEBUGFS
 41	select DMAR_PERF
 42	select DMAR_DEBUG
 43	help
 44	  !!!WARNING!!!
 45
 46	  DO NOT ENABLE THIS OPTION UNLESS YOU REALLY KNOW WHAT YOU ARE DOING!!!
 47
 48	  Expose Intel IOMMU internals in Debugfs.
 49
 50	  This option is -NOT- intended for production environments, and should
 51	  only be enabled for debugging Intel IOMMU.
 52
 53config INTEL_IOMMU_SVM
 54	bool "Support for Shared Virtual Memory with Intel IOMMU"
 55	depends on X86_64
 56	select MMU_NOTIFIER
 57	select IOMMU_SVA
 58	help
 59	  Shared Virtual Memory (SVM) provides a facility for devices
 60	  to access DMA resources through process address space by
 61	  means of a Process Address Space ID (PASID).
 62
 63config INTEL_IOMMU_DEFAULT_ON
 64	bool "Enable Intel DMA Remapping Devices by default"
 65	default y
 66	help
 67	  Selecting this option will enable a DMAR device at boot time if
 68	  one is found. If this option is not selected, DMAR support can
 69	  be enabled by passing intel_iommu=on to the kernel.
 70
 71config INTEL_IOMMU_FLOPPY_WA
 72	def_bool y
 73	depends on X86 && BLK_DEV_FD
 74	help
 75	  Floppy disk drivers are known to bypass DMA API calls
 76	  thereby failing to work when IOMMU is enabled. This
 77	  workaround will setup a 1:1 mapping for the first
 78	  16MiB to make floppy (an ISA device) work.
 79
 80config INTEL_IOMMU_SCALABLE_MODE_DEFAULT_ON
 81	bool "Enable Intel IOMMU scalable mode by default"
 82	default y
 83	help
 84	  Selecting this option will enable by default the scalable mode if
 85	  hardware presents the capability. The scalable mode is defined in
 86	  VT-d 3.0. The scalable mode capability could be checked by reading
 87	  /sys/devices/virtual/iommu/dmar*/intel-iommu/ecap. If this option
 88	  is not selected, scalable mode support could also be enabled by
 89	  passing intel_iommu=sm_on to the kernel. If not sure, please use
 90	  the default value.
 91
 92config INTEL_IOMMU_PERF_EVENTS
 93	bool "Intel IOMMU performance events"
 94	default y
 95	depends on INTEL_IOMMU && PERF_EVENTS
 96	help
 97	  Selecting this option will enable the performance monitoring
 98	  infrastructure in the Intel IOMMU. It collects information about
 99	  key events occurring during operation of the remapping hardware,
100	  to aid performance tuning and debug. These are available on modern
101	  processors which support Intel VT-d 4.0 and later.
102
103endif # INTEL_IOMMU