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Elixir Cross Referencer

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# SPDX-License-Identifier: GPL-2.0-only
# The IOVA library may also be used by non-CONFIG_IOMMU_API users
config CONFIG_IOMMU_IOVA
	tristate

# CONFIG_IOMMU_API always gets selected by whoever wants it.
config CONFIG_IOMMU_API
	bool

menuconfig CONFIG_IOMMU_SUPPORT
	bool "IOMMU Hardware Support"
	depends on CONFIG_MMU
	default y
	---help---
	  Say Y here if you want to compile device drivers for IO Memory
	  Management Units into the kernel. These devices usually allow to
	  remap DMA requests and/or remap interrupts from other devices on the
	  system.

if CONFIG_IOMMU_SUPPORT

menu "Generic IOMMU Pagetable Support"

# Selected by the actual pagetable implementations
config CONFIG_IOMMU_IO_PGTABLE
	bool

config CONFIG_IOMMU_IO_PGTABLE_LPAE
	bool "ARMv7/v8 Long Descriptor Format"
	select CONFIG_IOMMU_IO_PGTABLE
	depends on CONFIG_ARM || CONFIG_ARM64 || (CONFIG_COMPILE_TEST && !CONFIG_GENERIC_ATOMIC64)
	help
	  Enable support for the CONFIG_ARM long descriptor pagetable format.
	  This allocator supports 4K/2M/1G, 16K/32M and 64K/512M page
	  sizes at both stage-1 and stage-2, as well as address spaces
	  up to 48-bits in size.

config CONFIG_IOMMU_IO_PGTABLE_LPAE_SELFTEST
	bool "LPAE selftests"
	depends on CONFIG_IOMMU_IO_PGTABLE_LPAE
	help
	  Enable self-tests for LPAE page table allocator. This performs
	  a series of page-table consistency checks during boot.

	  If unsure, say N here.

config CONFIG_IOMMU_IO_PGTABLE_ARMV7S
	bool "ARMv7/v8 Short Descriptor Format"
	select CONFIG_IOMMU_IO_PGTABLE
	depends on CONFIG_ARM || CONFIG_ARM64 || CONFIG_COMPILE_TEST
	help
	  Enable support for the CONFIG_ARM Short-descriptor pagetable format.
	  This supports 32-bit virtual and physical addresses mapped using
	  2-level tables with 4KB pages/1MB sections, and contiguous entries
	  for 64KB pages/16MB supersections if indicated by the IOMMU driver.

config CONFIG_IOMMU_IO_PGTABLE_ARMV7S_SELFTEST
	bool "ARMv7s selftests"
	depends on CONFIG_IOMMU_IO_PGTABLE_ARMV7S
	help
	  Enable self-tests for ARMv7s page table allocator. This performs
	  a series of page-table consistency checks during boot.

	  If unsure, say N here.

endmenu

config CONFIG_IOMMU_DEBUGFS
	bool "Export IOMMU internals in DebugFS"
	depends on CONFIG_DEBUG_FS
	help
	  Allows exposure of IOMMU device internals. This option enables
	  the use of debugfs by IOMMU drivers as required. Devices can,
	  at initialization time, cause the IOMMU code to create a top-level
	  debug/iommu directory, and then populate a subdirectory with
	  entries as required.

config CONFIG_IOMMU_DEFAULT_PASSTHROUGH
	bool "IOMMU passthrough by default"
	depends on CONFIG_IOMMU_API
        help
	  Enable passthrough by default, removing the need to pass in
	  iommu.passthrough=on or iommu=pt through command line. If this
	  is enabled, you can still disable with iommu.passthrough=off
	  or iommu=nopt depending on the architecture.

	  If unsure, say N here.

config CONFIG_OF_IOMMU
       def_bool y
       depends on CONFIG_OF && CONFIG_IOMMU_API

# IOMMU-agnostic DMA-mapping layer
config CONFIG_IOMMU_DMA
	bool
	select CONFIG_IOMMU_API
	select CONFIG_IOMMU_IOVA
	select CONFIG_IRQ_MSI_IOMMU
	select CONFIG_NEED_SG_DMA_LENGTH

config CONFIG_FSL_PAMU
	bool "Freescale IOMMU support"
	depends on CONFIG_PCI
	depends on CONFIG_PHYS_64BIT
	depends on CONFIG_PPC_E500MC || (CONFIG_COMPILE_TEST && CONFIG_PPC)
	select CONFIG_IOMMU_API
	select CONFIG_GENERIC_ALLOCATOR
	help
	  Freescale PAMU support. PAMU is the IOMMU present on Freescale QorIQ platforms.
	  PAMU can authorize memory access, remap the memory address, and remap I/O
	  transaction types.

# MSM IOMMU support
config CONFIG_MSM_IOMMU
	bool "MSM IOMMU Support"
	depends on CONFIG_ARM
	depends on CONFIG_ARCH_MSM8X60 || CONFIG_ARCH_MSM8960 || CONFIG_COMPILE_TEST
	select CONFIG_IOMMU_API
	select CONFIG_IOMMU_IO_PGTABLE_ARMV7S
	help
	  Support for the IOMMUs found on certain Qualcomm SOCs.
	  These IOMMUs allow virtualization of the address space used by most
	  cores within the multimedia subsystem.

	  If unsure, say N here.

config CONFIG_IOMMU_PGTABLES_L2
	def_bool y
	depends on CONFIG_MSM_IOMMU && CONFIG_MMU && CONFIG_SMP && CONFIG_CPU_DCACHE_DISABLE=n

# AMD IOMMU support
config CONFIG_AMD_IOMMU
	bool "AMD IOMMU support"
	select CONFIG_SWIOTLB
	select CONFIG_PCI_MSI
	select CONFIG_PCI_ATS
	select CONFIG_PCI_PRI
	select CONFIG_PCI_PASID
	select CONFIG_IOMMU_API
	select CONFIG_IOMMU_IOVA
	depends on CONFIG_X86_64 && CONFIG_PCI && CONFIG_ACPI
	---help---
	  With this option you can enable support for AMD IOMMU hardware in
	  your system. An IOMMU is a hardware component which provides
	  remapping of DMA memory accesses from devices. With an AMD IOMMU you
	  can isolate the DMA memory of different devices and protect the
	  system from misbehaving device drivers or hardware.

	  You can find out if your system has an AMD IOMMU if you look into
	  your BIOS for an option to enable it or if you have an IVRS CONFIG_ACPI
	  table.

config CONFIG_AMD_IOMMU_V2
	tristate "AMD IOMMU Version 2 driver"
	depends on CONFIG_AMD_IOMMU
	select CONFIG_MMU_NOTIFIER
	---help---
	  This option enables support for the AMD IOMMUv2 features of the IOMMU
	  hardware. Select this option if you want to use devices that support
	  the CONFIG_PCI PRI and PASID interface.

config CONFIG_AMD_IOMMU_DEBUGFS
	bool "Enable AMD IOMMU internals in DebugFS"
	depends on CONFIG_AMD_IOMMU && CONFIG_IOMMU_DEBUGFS
	---help---
	  !!!WARNING!!!  !!!WARNING!!!  !!!WARNING!!!  !!!WARNING!!!

	  DO NOT ENABLE THIS OPTION UNLESS YOU REALLY, -REALLY- KNOW WHAT YOU ARE DOING!!!
	  Exposes AMD IOMMU device internals in DebugFS.

	  This option is -NOT- intended for production environments, and should
	  not generally be enabled.

# Intel IOMMU support
config CONFIG_DMAR_TABLE
	bool

config CONFIG_INTEL_IOMMU
	bool "Support for Intel IOMMU using DMA Remapping Devices"
	depends on CONFIG_PCI_MSI && CONFIG_ACPI && (CONFIG_X86 || CONFIG_IA64)
	select CONFIG_IOMMU_API
	select CONFIG_IOMMU_IOVA
	select CONFIG_NEED_DMA_MAP_STATE
	select CONFIG_DMAR_TABLE
	select CONFIG_SWIOTLB
	help
	  DMA remapping (DMAR) devices support enables independent address
	  translations for Direct Memory Access (DMA) from devices.
	  These DMA remapping devices are reported via CONFIG_ACPI tables
	  and include CONFIG_PCI device scope covered by these DMA
	  remapping devices.

config CONFIG_INTEL_IOMMU_DEBUGFS
	bool "Export Intel IOMMU internals in Debugfs"
	depends on CONFIG_INTEL_IOMMU && CONFIG_IOMMU_DEBUGFS
	help
	  !!!WARNING!!!

	  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.

config CONFIG_INTEL_IOMMU_SVM
	bool "Support for Shared Virtual Memory with Intel IOMMU"
	depends on CONFIG_INTEL_IOMMU && CONFIG_X86
	select CONFIG_PCI_PASID
	select CONFIG_MMU_NOTIFIER
	help
	  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).

config CONFIG_INTEL_IOMMU_DEFAULT_ON
	def_bool y
	prompt "Enable Intel DMA Remapping Devices by default"
	depends on CONFIG_INTEL_IOMMU
	help
	  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.

config CONFIG_INTEL_IOMMU_BROKEN_GFX_WA
	bool "Workaround broken graphics drivers (going away soon)"
	depends on CONFIG_INTEL_IOMMU && CONFIG_BROKEN && CONFIG_X86
	---help---
	  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.

config CONFIG_INTEL_IOMMU_FLOPPY_WA
	def_bool y
	depends on CONFIG_INTEL_IOMMU && CONFIG_X86
	---help---
	  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 CONFIG_ISA device) work.

config CONFIG_IRQ_REMAP
	bool "Support for Interrupt Remapping"
	depends on CONFIG_X86_64 && CONFIG_X86_IO_APIC && CONFIG_PCI_MSI && CONFIG_ACPI
	select CONFIG_DMAR_TABLE
	---help---
	  Supports Interrupt remapping for IO-APIC and MSI devices.
	  To use x2apic mode in the CPU's which support x2APIC enhancements or
	  to support platforms with CPU's having > 8 bit APIC ID, say Y.

# OMAP IOMMU support
config CONFIG_OMAP_IOMMU
	bool "OMAP IOMMU Support"
	depends on CONFIG_ARM && CONFIG_MMU
	depends on CONFIG_ARCH_OMAP2PLUS || CONFIG_COMPILE_TEST
	select CONFIG_IOMMU_API
	---help---
	  The OMAP3 media platform drivers depend on iommu support,
	  if you need them say Y here.

config CONFIG_OMAP_IOMMU_DEBUG
	bool "Export OMAP IOMMU internals in DebugFS"
	depends on CONFIG_OMAP_IOMMU && CONFIG_DEBUG_FS
	---help---
	  Select this to see extensive information about
	  the internal state of OMAP IOMMU in debugfs.

	  Say N unless you know you need this.

config CONFIG_ROCKCHIP_IOMMU
	bool "Rockchip IOMMU Support"
	depends on CONFIG_ARM || CONFIG_ARM64
	depends on CONFIG_ARCH_ROCKCHIP || CONFIG_COMPILE_TEST
	select CONFIG_IOMMU_API
	select CONFIG_ARM_DMA_USE_IOMMU
	help
	  Support for IOMMUs found on Rockchip rk32xx SOCs.
	  These IOMMUs allow virtualization of the address space used by most
	  cores within the multimedia subsystem.
	  Say Y here if you are using a Rockchip SoC that includes an IOMMU
	  device.

config CONFIG_TEGRA_IOMMU_GART
	bool "Tegra GART IOMMU Support"
	depends on CONFIG_ARCH_TEGRA_2x_SOC
	depends on CONFIG_TEGRA_MC
	select CONFIG_IOMMU_API
	help
	  Enables support for remapping discontiguous physical memory
	  shared with the operating system into contiguous I/O virtual
	  space through the GART (Graphics Address Relocation Table)
	  hardware included on Tegra SoCs.

config CONFIG_TEGRA_IOMMU_SMMU
	bool "NVIDIA Tegra SMMU Support"
	depends on CONFIG_ARCH_TEGRA
	depends on CONFIG_TEGRA_AHB
	depends on CONFIG_TEGRA_MC
	select CONFIG_IOMMU_API
	help
	  This driver supports the IOMMU hardware (SMMU) found on NVIDIA Tegra
	  SoCs (Tegra30 up to Tegra210).

config CONFIG_EXYNOS_IOMMU
	bool "Exynos IOMMU Support"
	depends on CONFIG_ARCH_EXYNOS && CONFIG_MMU
	depends on !CONFIG_CPU_BIG_ENDIAN # revisit driver if we can enable big-endian ptes
	select CONFIG_IOMMU_API
	select CONFIG_ARM_DMA_USE_IOMMU
	help
	  Support for the IOMMU (System CONFIG_MMU) of Samsung Exynos application
	  processor family. This enables H/W multimedia accelerators to see
	  non-linear physical memory chunks as linear memory in their
	  address space.

	  If unsure, say N here.

config CONFIG_EXYNOS_IOMMU_DEBUG
	bool "Debugging log for Exynos IOMMU"
	depends on CONFIG_EXYNOS_IOMMU
	help
	  Select this to see the detailed log message that shows what
	  happens in the IOMMU driver.

	  Say N unless you need kernel log message for IOMMU debugging.

config CONFIG_IPMMU_VMSA
	bool "Renesas VMSA-compatible IPMMU"
	depends on CONFIG_ARM || CONFIG_IOMMU_DMA
	depends on CONFIG_ARCH_RENESAS || (CONFIG_COMPILE_TEST && !CONFIG_GENERIC_ATOMIC64)
	select CONFIG_IOMMU_API
	select CONFIG_IOMMU_IO_PGTABLE_LPAE
	select CONFIG_ARM_DMA_USE_IOMMU
	help
	  Support for the Renesas VMSA-compatible IPMMU found in the R-Mobile
	  APE6, R-Car Gen2, and R-Car Gen3 SoCs.

	  If unsure, say N.

config CONFIG_SPAPR_TCE_IOMMU
	bool "sPAPR TCE IOMMU Support"
	depends on CONFIG_PPC_POWERNV || CONFIG_PPC_PSERIES
	select CONFIG_IOMMU_API
	help
	  Enables bits of IOMMU API required by CONFIG_VFIO. The iommu_ops
	  is not implemented as it is not necessary for CONFIG_VFIO.

# CONFIG_ARM IOMMU support
config CONFIG_ARM_SMMU
	bool "ARM Ltd. System MMU (SMMU) Support"
	depends on (CONFIG_ARM64 || CONFIG_ARM) && CONFIG_MMU
	select CONFIG_IOMMU_API
	select CONFIG_IOMMU_IO_PGTABLE_LPAE
	select CONFIG_ARM_DMA_USE_IOMMU if CONFIG_ARM
	help
	  Support for implementations of the CONFIG_ARM System CONFIG_MMU architecture
	  versions 1 and 2.

	  Say Y here if your SoC includes an IOMMU device implementing
	  the CONFIG_ARM SMMU architecture.

config CONFIG_ARM_SMMU_DISABLE_BYPASS_BY_DEFAULT
	bool "Default to disabling bypass on ARM SMMU v1 and v2"
	depends on CONFIG_ARM_SMMU
	default y
	help
	  Say Y here to (by default) disable bypass streams such that
	  incoming transactions from devices that are not attached to
	  an iommu domain will report an abort back to the device and
	  will not be allowed to pass through the SMMU.

	  Any old kernels that existed before this KConfig was
	  introduced would default to _allowing_ bypass (AKA the
	  equivalent of NO for this config).  However the default for
	  this option is YES because the old behavior is insecure.

	  There are few reasons to allow unmatched stream bypass, and
	  even fewer good ones.  If saying YES here breaks your board
	  you should work on fixing your board.  This KConfig option
	  is expected to be removed in the future and we'll simply
	  hardcode the bypass disable in the code.

	  NOTE: the kernel command line parameter
	  'arm-smmu.disable_bypass' will continue to override this
	  config.

config CONFIG_ARM_SMMU_V3
	bool "ARM Ltd. System MMU Version 3 (SMMUv3) Support"
	depends on CONFIG_ARM64
	select CONFIG_IOMMU_API
	select CONFIG_IOMMU_IO_PGTABLE_LPAE
	select CONFIG_GENERIC_MSI_IRQ_DOMAIN
	help
	  Support for implementations of the CONFIG_ARM System CONFIG_MMU architecture
	  version 3 providing translation support to a PCIe root complex.

	  Say Y here if your system includes an IOMMU device implementing
	  the CONFIG_ARM SMMUv3 architecture.

config CONFIG_S390_IOMMU
	def_bool y if CONFIG_S390 && CONFIG_PCI
	depends on CONFIG_S390 && CONFIG_PCI
	select CONFIG_IOMMU_API
	help
	  Support for the IOMMU API for s390 CONFIG_PCI devices.

config CONFIG_S390_CCW_IOMMU
	bool "S390 CCW IOMMU Support"
	depends on CONFIG_S390 && CONFIG_CCW
	select CONFIG_IOMMU_API
	help
	  Enables bits of IOMMU API required by CONFIG_VFIO. The iommu_ops
	  is not implemented as it is not necessary for CONFIG_VFIO.

config CONFIG_S390_AP_IOMMU
	bool "S390 AP IOMMU Support"
	depends on CONFIG_S390 && CONFIG_ZCRYPT
	select CONFIG_IOMMU_API
	help
	  Enables bits of IOMMU API required by CONFIG_VFIO. The iommu_ops
	  is not implemented as it is not necessary for CONFIG_VFIO.

config CONFIG_MTK_IOMMU
	bool "MTK IOMMU Support"
	depends on CONFIG_ARM || CONFIG_ARM64
	depends on CONFIG_ARCH_MEDIATEK || CONFIG_COMPILE_TEST
	select CONFIG_ARM_DMA_USE_IOMMU
	select CONFIG_IOMMU_API
	select CONFIG_IOMMU_DMA
	select CONFIG_IOMMU_IO_PGTABLE_ARMV7S
	select CONFIG_MEMORY
	select CONFIG_MTK_SMI
	help
	  Support for the M4U on certain Mediatek SOCs. M4U is MultiMedia
	  Memory Management Unit. This option enables remapping of DMA memory
	  accesses for the multimedia subsystem.

	  If unsure, say N here.

config CONFIG_MTK_IOMMU_V1
	bool "MTK IOMMU Version 1 (M4U gen1) Support"
	depends on CONFIG_ARM
	depends on CONFIG_ARCH_MEDIATEK || CONFIG_COMPILE_TEST
	select CONFIG_ARM_DMA_USE_IOMMU
	select CONFIG_IOMMU_API
	select CONFIG_MEMORY
	select CONFIG_MTK_SMI
	help
	  Support for the M4U on certain Mediatek SoCs. M4U generation 1 HW is
	  Multimedia Memory Managememt Unit. This option enables remapping of
	  DMA memory accesses for the multimedia subsystem.

	  if unsure, say N here.

config CONFIG_QCOM_IOMMU
	# Note: iommu drivers cannot (yet?) be built as modules
	bool "Qualcomm IOMMU Support"
	depends on CONFIG_ARCH_QCOM || (CONFIG_COMPILE_TEST && !CONFIG_GENERIC_ATOMIC64)
	select CONFIG_IOMMU_API
	select CONFIG_IOMMU_IO_PGTABLE_LPAE
	select CONFIG_ARM_DMA_USE_IOMMU
	help
	  Support for IOMMU on certain Qualcomm SoCs.

config CONFIG_HYPERV_IOMMU
	bool "Hyper-V x2APIC IRQ Handling"
	depends on CONFIG_HYPERV
	select CONFIG_IOMMU_API
	default CONFIG_HYPERV
	help
	  Stub IOMMU driver to handle IRQs as to allow Hyper-V Linux
	  guests to run with x2APIC mode enabled.

config CONFIG_VIRTIO_IOMMU
	bool "Virtio IOMMU driver"
	depends on CONFIG_VIRTIO=y
	depends on CONFIG_ARM64
	select CONFIG_IOMMU_API
	select CONFIG_INTERVAL_TREE
	help
	  Para-virtualised IOMMU driver with virtio.

	  Say Y here if you intend to run this kernel as a guest.

endif # CONFIG_IOMMU_SUPPORT