linux_dsm_epyc7002/drivers/iommu/Kconfig

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

menuconfig IOMMU_SUPPORT
	bool "IOMMU Hardware Support"
	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 IOMMU_SUPPORT

# MSM IOMMU support
config MSM_IOMMU
	bool "MSM IOMMU Support"
	depends on ARCH_MSM8X60 || ARCH_MSM8960
	select IOMMU_API
	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 IOMMU_PGTABLES_L2
	def_bool y
	depends on MSM_IOMMU && MMU && SMP && CPU_DCACHE_DISABLE=n

# AMD IOMMU support
config AMD_IOMMU
	bool "AMD IOMMU support"
	select SWIOTLB
	select PCI_MSI
	select PCI_IOV
	select IOMMU_API
	depends on X86_64 && PCI && 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 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 ACPI
	  table.

config AMD_IOMMU_STATS
	bool "Export AMD IOMMU statistics to debugfs"
	depends on AMD_IOMMU
	select DEBUG_FS
	---help---
	  This option enables code in the AMD IOMMU driver to collect various
	  statistics about whats happening in the driver and exports that
	  information to userspace via debugfs.
	  If unsure, say N.

# Intel IOMMU support
config DMAR
	bool "Support for DMA Remapping Devices"
	depends on PCI_MSI && ACPI && (X86 || IA64_GENERIC)
	select IOMMU_API
	help
	  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
	  remapping devices.

config DMAR_DEFAULT_ON
	def_bool y
	prompt "Enable DMA Remapping Devices by default"
	depends on DMAR
	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 DMAR_BROKEN_GFX_WA
	bool "Workaround broken graphics drivers (going away soon)"
	depends on DMAR && BROKEN && 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 DMAR_FLOPPY_WA
	def_bool y
	depends on DMAR && 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 ISA device) work.

config INTR_REMAP
	bool "Support for Interrupt Remapping (EXPERIMENTAL)"
	depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
	---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.

endif # IOMMU_SUPPORT