Linux v6.2-rc7 - intel
# SPDX-License-Identifier: GPL-2.0-only
# Intel IOMMU support
bool "Support for Intel IOMMU using DMA Remapping Devices"
depends on PCI_MSI && ACPI && (X86 || IA64)
DMA remapping (DMAR) devices support enables independent address
translations for Direct Memory Access (DMA) from devices.
These DMA remapping devices are reported via ACPI tables
and include PCI device scope covered by these DMA
bool "Export Intel IOMMU internals in Debugfs"
depends on IOMMU_DEBUGFS
DO NOT ENABLE THIS OPTION UNLESS YOU REALLY KNOW WHAT YOU ARE DOING!!!
Expose Intel IOMMU internals in Debugfs.
This option is -NOT- intended for production environments, and should
only be enabled for debugging Intel IOMMU.
bool "Support for Shared Virtual Memory with Intel IOMMU"
depends on X86_64
Shared Virtual Memory (SVM) provides a facility for devices
to access DMA resources through process address space by
means of a Process Address Space ID (PASID).
bool "Enable Intel DMA Remapping Devices by default"
Selecting this option will enable a DMAR device at boot time if
one is found. If this option is not selected, DMAR support can
be enabled by passing intel_iommu=on to the kernel.
bool "Workaround broken graphics drivers (going away soon)"
depends on BROKEN && X86
Current Graphics drivers tend to use physical address
for DMA and avoid using DMA APIs. Setting this config
option permits the IOMMU driver to set a unity map for
all the OS-visible memory. Hence the driver can continue
to use physical addresses for DMA, at least until this
option is removed in the 2.6.32 kernel.
depends on X86
Floppy disk drivers are known to bypass DMA API calls
thereby failing to work when IOMMU is enabled. This
workaround will setup a 1:1 mapping for the first
16MiB to make floppy (an ISA device) work.
bool "Enable Intel IOMMU scalable mode by default"
Selecting this option will enable by default the scalable mode if
hardware presents the capability. The scalable mode is defined in
VT-d 3.0. The scalable mode capability could be checked by reading
/sys/devices/virtual/iommu/dmar*/intel-iommu/ecap. If this option
is not selected, scalable mode support could also be enabled by
passing intel_iommu=sm_on to the kernel. If not sure, please use
the default value.
endif # INTEL_IOMMU