Kconfig (3073B)
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 || IA64) 15 select DMA_OPS 16 select IOMMU_API 17 select IOMMU_IOVA 18 select NEED_DMA_MAP_STATE 19 select DMAR_TABLE 20 select SWIOTLB 21 select IOASID 22 select IOMMU_DMA 23 select PCI_ATS 24 help 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 29 remapping devices. 30 31if INTEL_IOMMU 32 33config INTEL_IOMMU_DEBUGFS 34 bool "Export Intel IOMMU internals in Debugfs" 35 depends on IOMMU_DEBUGFS 36 select DMAR_PERF 37 select DMAR_DEBUG 38 help 39 !!!WARNING!!! 40 41 DO NOT ENABLE THIS OPTION UNLESS YOU REALLY KNOW WHAT YOU ARE DOING!!! 42 43 Expose Intel IOMMU internals in Debugfs. 44 45 This option is -NOT- intended for production environments, and should 46 only be enabled for debugging Intel IOMMU. 47 48config INTEL_IOMMU_SVM 49 bool "Support for Shared Virtual Memory with Intel IOMMU" 50 depends on X86_64 51 select PCI_PASID 52 select PCI_PRI 53 select MMU_NOTIFIER 54 select IOASID 55 select IOMMU_SVA 56 help 57 Shared Virtual Memory (SVM) provides a facility for devices 58 to access DMA resources through process address space by 59 means of a Process Address Space ID (PASID). 60 61config INTEL_IOMMU_DEFAULT_ON 62 bool "Enable Intel DMA Remapping Devices by default" 63 default y 64 help 65 Selecting this option will enable a DMAR device at boot time if 66 one is found. If this option is not selected, DMAR support can 67 be enabled by passing intel_iommu=on to the kernel. 68 69config INTEL_IOMMU_BROKEN_GFX_WA 70 bool "Workaround broken graphics drivers (going away soon)" 71 depends on BROKEN && X86 72 help 73 Current Graphics drivers tend to use physical address 74 for DMA and avoid using DMA APIs. Setting this config 75 option permits the IOMMU driver to set a unity map for 76 all the OS-visible memory. Hence the driver can continue 77 to use physical addresses for DMA, at least until this 78 option is removed in the 2.6.32 kernel. 79 80config INTEL_IOMMU_FLOPPY_WA 81 def_bool y 82 depends on X86 83 help 84 Floppy disk drivers are known to bypass DMA API calls 85 thereby failing to work when IOMMU is enabled. This 86 workaround will setup a 1:1 mapping for the first 87 16MiB to make floppy (an ISA device) work. 88 89config INTEL_IOMMU_SCALABLE_MODE_DEFAULT_ON 90 bool "Enable Intel IOMMU scalable mode by default" 91 default y 92 help 93 Selecting this option will enable by default the scalable mode if 94 hardware presents the capability. The scalable mode is defined in 95 VT-d 3.0. The scalable mode capability could be checked by reading 96 /sys/devices/virtual/iommu/dmar*/intel-iommu/ecap. If this option 97 is not selected, scalable mode support could also be enabled by 98 passing intel_iommu=sm_on to the kernel. If not sure, please use 99 the default value. 100 101endif # INTEL_IOMMU