1menuconfig LIBNVDIMM
  2	tristate "NVDIMM (Non-Volatile Memory Device) Support"
  3	depends on PHYS_ADDR_T_64BIT
  4	depends on HAS_IOMEM
  5	depends on BLK_DEV
  6	help
  7	  Generic support for non-volatile memory devices including
  8	  ACPI-6-NFIT defined resources.  On platforms that define an
  9	  NFIT, or otherwise can discover NVDIMM resources, a libnvdimm
 10	  bus is registered to advertise PMEM (persistent memory)
 11	  namespaces (/dev/pmemX) and BLK (sliding mmio window(s))
 12	  namespaces (/dev/ndblkX.Y). A PMEM namespace refers to a
 13	  memory resource that may span multiple DIMMs and support DAX
 14	  (see CONFIG_DAX).  A BLK namespace refers to an NVDIMM control
 15	  region which exposes an mmio register set for windowed access
 16	  mode to non-volatile memory.
 17
 18if LIBNVDIMM
 19
 20config BLK_DEV_PMEM
 21	tristate "PMEM: Persistent memory block device support"
 22	default LIBNVDIMM
 23	select ND_BTT if BTT
 24	select ND_PFN if NVDIMM_PFN
 25	help
 26	  Memory ranges for PMEM are described by either an NFIT
 27	  (NVDIMM Firmware Interface Table, see CONFIG_NFIT_ACPI), a
 28	  non-standard OEM-specific E820 memory type (type-12, see
 29	  CONFIG_X86_PMEM_LEGACY), or it is manually specified by the
 30	  'memmap=nn[KMG]!ss[KMG]' kernel command line (see
 31	  Documentation/admin-guide/kernel-parameters.rst).  This driver converts
 32	  these persistent memory ranges into block devices that are
 33	  capable of DAX (direct-access) file system mappings.  See
 34	  Documentation/nvdimm/nvdimm.txt for more details.
 35
 36	  Say Y if you want to use an NVDIMM
 37
 38config ND_BLK
 39	tristate "BLK: Block data window (aperture) device support"
 40	default LIBNVDIMM
 41	select ND_BTT if BTT
 42	help
 43	  Support NVDIMMs, or other devices, that implement a BLK-mode
 44	  access capability.  BLK-mode access uses memory-mapped-i/o
 45	  apertures to access persistent media.
 46
 47	  Say Y if your platform firmware emits an ACPI.NFIT table
 48	  (CONFIG_ACPI_NFIT), or otherwise exposes BLK-mode
 49	  capabilities.
 50
 51config ND_CLAIM
 52	bool
 53
 54config ND_BTT
 55	tristate
 56
 57config BTT
 58	bool "BTT: Block Translation Table (atomic sector updates)"
 59	default y if LIBNVDIMM
 60	select ND_CLAIM
 61	help
 62	  The Block Translation Table (BTT) provides atomic sector
 63	  update semantics for persistent memory devices, so that
 64	  applications that rely on sector writes not being torn (a
 65	  guarantee that typical disks provide) can continue to do so.
 66	  The BTT manifests itself as an alternate personality for an
 67	  NVDIMM namespace, i.e. a namespace can be in raw mode (pmemX,
 68	  ndblkX.Y, etc...), or 'sectored' mode, (pmemXs, ndblkX.Ys,
 69	  etc...).
 70
 71	  Select Y if unsure
 72
 73config ND_PFN
 74	tristate
 75
 76config NVDIMM_PFN
 77	bool "PFN: Map persistent (device) memory"
 78	default LIBNVDIMM
 79	depends on ZONE_DEVICE
 80	select ND_CLAIM
 81	help
 82	  Map persistent memory, i.e. advertise it to the memory
 83	  management sub-system.  By default persistent memory does
 84	  not support direct I/O, RDMA, or any other usage that
 85	  requires a 'struct page' to mediate an I/O request.  This
 86	  driver allocates and initializes the infrastructure needed
 87	  to support those use cases.
 88
 89	  Select Y if unsure
 90
 91config NVDIMM_DAX
 92	bool "NVDIMM DAX: Raw access to persistent memory"
 93	default LIBNVDIMM
 94	depends on NVDIMM_PFN
 95	help
 96	  Support raw device dax access to a persistent memory
 97	  namespace.  For environments that want to hard partition
 98	  peristent memory, this capability provides a mechanism to
 99	  sub-divide a namespace into character devices that can only be
100	  accessed via DAX (mmap(2)).
101
102	  Select Y if unsure
103
104endif