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# SPDX-License-Identifier: GPL-2.0-only
menuconfig CONFIG_LIBNVDIMM
	tristate "NVDIMM (Non-Volatile Memory Device) Support"
	depends on CONFIG_PHYS_ADDR_T_64BIT
	depends on CONFIG_HAS_IOMEM
	depends on CONFIG_BLK_DEV
	help
	  Generic support for non-volatile memory devices including
	  CONFIG_ACPI-6-NFIT defined resources.  On platforms that define an
	  NFIT, or otherwise can discover NVDIMM resources, a libnvdimm
	  bus is registered to advertise PMEM (persistent memory)
	  namespaces (/dev/pmemX) and BLK (sliding mmio window(s))
	  namespaces (/dev/ndblkX.Y). CONFIG_A PMEM namespace refers to a
	  memory resource that may span multiple DIMMs and support CONFIG_DAX
	  (see CONFIG_DAX).  CONFIG_A BLK namespace refers to an NVDIMM control
	  region which exposes an mmio register set for windowed access
	  mode to non-volatile memory.

if CONFIG_LIBNVDIMM

config CONFIG_BLK_DEV_PMEM
	tristate "PMEM: Persistent memory block device support"
	default CONFIG_LIBNVDIMM
	select CONFIG_DAX_DRIVER
	select CONFIG_ND_BTT if CONFIG_BTT
	select CONFIG_ND_PFN if CONFIG_NVDIMM_PFN
	help
	  Memory ranges for PMEM are described by either an NFIT
	  (NVDIMM Firmware Interface Table, see CONFIG_NFIT_ACPI), a
	  non-standard OEM-specific E820 memory type (type-12, see
	  CONFIG_X86_PMEM_LEGACY), or it is manually specified by the
	  'memmap=nn[KMG]!ss[KMG]' kernel command line (see
	  Documentation/admin-guide/kernel-parameters.rst).  This driver converts
	  these persistent memory ranges into block devices that are
	  capable of CONFIG_DAX (direct-access) file system mappings.  See
	  Documentation/driver-api/nvdimm/nvdimm.rst for more details.

	  Say Y if you want to use an NVDIMM

config CONFIG_ND_BLK
	tristate "BLK: Block data window (aperture) device support"
	default CONFIG_LIBNVDIMM
	select CONFIG_ND_BTT if CONFIG_BTT
	help
	  Support NVDIMMs, or other devices, that implement a BLK-mode
	  access capability.  BLK-mode access uses memory-mapped-i/o
	  apertures to access persistent media.

	  Say Y if your platform firmware emits an CONFIG_ACPI.NFIT table
	  (CONFIG_ACPI_NFIT), or otherwise exposes BLK-mode
	  capabilities.

config CONFIG_ND_CLAIM
	bool

config CONFIG_ND_BTT
	tristate

config CONFIG_BTT
	bool "BTT: Block Translation Table (atomic sector updates)"
	default y if CONFIG_LIBNVDIMM
	select CONFIG_ND_CLAIM
	help
	  The Block Translation Table (CONFIG_BTT) provides atomic sector
	  update semantics for persistent memory devices, so that
	  applications that rely on sector writes not being torn (a
	  guarantee that typical disks provide) can continue to do so.
	  The CONFIG_BTT manifests itself as an alternate personality for an
	  NVDIMM namespace, i.e. a namespace can be in raw mode (pmemX,
	  ndblkX.Y, etc...), or 'sectored' mode, (pmemXs, ndblkX.Ys,
	  etc...).

	  Select Y if unsure

config CONFIG_ND_PFN
	tristate

config CONFIG_NVDIMM_PFN
	bool "PFN: Map persistent (device) memory"
	default CONFIG_LIBNVDIMM
	depends on CONFIG_ZONE_DEVICE
	select CONFIG_ND_CLAIM
	help
	  Map persistent memory, i.e. advertise it to the memory
	  management sub-system.  By default persistent memory does
	  not support direct I/O, RDMA, or any other usage that
	  requires a 'struct page' to mediate an I/O request.  This
	  driver allocates and initializes the infrastructure needed
	  to support those use cases.

	  Select Y if unsure

config CONFIG_NVDIMM_DAX
	bool "NVDIMM DAX: Raw access to persistent memory"
	default CONFIG_LIBNVDIMM
	depends on CONFIG_NVDIMM_PFN
	help
	  Support raw device dax access to a persistent memory
	  namespace.  For environments that want to hard partition
	  persistent memory, this capability provides a mechanism to
	  sub-divide a namespace into character devices that can only be
	  accessed via CONFIG_DAX (mmap(2)).

	  Select Y if unsure

config CONFIG_OF_PMEM
	tristate "Device-tree support for persistent memory regions"
	depends on CONFIG_OF
	default CONFIG_LIBNVDIMM
	help
	  Allows regions of persistent memory to be described in the
	  device-tree.

	  Select Y if unsure.

config CONFIG_NVDIMM_KEYS
	def_bool y
	depends on CONFIG_ENCRYPTED_KEYS
	depends on (CONFIG_LIBNVDIMM=CONFIG_ENCRYPTED_KEYS) || CONFIG_LIBNVDIMM=m

config CONFIG_NVDIMM_TEST_BUILD
	tristate "Build the unit test core"
	depends on m
	depends on CONFIG_COMPILE_TEST && CONFIG_X86_64
	default m if CONFIG_COMPILE_TEST
	help
	  Build the core of the unit test infrastructure. The result of
	  this build is non-functional for unit test execution, but it
	  otherwise helps catch build errors induced by changes to the
	  core devm_memremap_pages() implementation and other
	  infrastructure.

endif