1# SPDX-License-Identifier: GPL-2.0-only 2menuconfig LIBNVDIMM 3 tristate "NVDIMM (Non-Volatile Memory Device) Support" 4 depends on PHYS_ADDR_T_64BIT 5 depends on HAS_IOMEM 6 depends on BLK_DEV 7 help 8 Generic support for non-volatile memory devices including 9 ACPI-6-NFIT defined resources. On platforms that define an 10 NFIT, or otherwise can discover NVDIMM resources, a libnvdimm 11 bus is registered to advertise PMEM (persistent memory) 12 namespaces (/dev/pmemX) and BLK (sliding mmio window(s)) 13 namespaces (/dev/ndblkX.Y). A PMEM namespace refers to a 14 memory resource that may span multiple DIMMs and support DAX 15 (see CONFIG_DAX). A BLK namespace refers to an NVDIMM control 16 region which exposes an mmio register set for windowed access 17 mode to non-volatile memory. 18 19if LIBNVDIMM 20 21config BLK_DEV_PMEM 22 tristate "PMEM: Persistent memory block device support" 23 default LIBNVDIMM 24 select DAX_DRIVER 25 select ND_BTT if BTT 26 select ND_PFN if NVDIMM_PFN 27 help 28 Memory ranges for PMEM are described by either an NFIT 29 (NVDIMM Firmware Interface Table, see CONFIG_NFIT_ACPI), a 30 non-standard OEM-specific E820 memory type (type-12, see 31 CONFIG_X86_PMEM_LEGACY), or it is manually specified by the 32 'memmap=nn[KMG]!ss[KMG]' kernel command line (see 33 Documentation/admin-guide/kernel-parameters.rst). This driver converts 34 these persistent memory ranges into block devices that are 35 capable of DAX (direct-access) file system mappings. See 36 Documentation/driver-api/nvdimm/nvdimm.rst for more details. 37 38 Say Y if you want to use an NVDIMM 39 40config ND_BLK 41 tristate "BLK: Block data window (aperture) device support" 42 default LIBNVDIMM 43 select ND_BTT if BTT 44 help 45 Support NVDIMMs, or other devices, that implement a BLK-mode 46 access capability. BLK-mode access uses memory-mapped-i/o 47 apertures to access persistent media. 48 49 Say Y if your platform firmware emits an ACPI.NFIT table 50 (CONFIG_ACPI_NFIT), or otherwise exposes BLK-mode 51 capabilities. 52 53config ND_CLAIM 54 bool 55 56config ND_BTT 57 tristate 58 59config BTT 60 bool "BTT: Block Translation Table (atomic sector updates)" 61 default y if LIBNVDIMM 62 select ND_CLAIM 63 help 64 The Block Translation Table (BTT) provides atomic sector 65 update semantics for persistent memory devices, so that 66 applications that rely on sector writes not being torn (a 67 guarantee that typical disks provide) can continue to do so. 68 The BTT manifests itself as an alternate personality for an 69 NVDIMM namespace, i.e. a namespace can be in raw mode (pmemX, 70 ndblkX.Y, etc...), or 'sectored' mode, (pmemXs, ndblkX.Ys, 71 etc...). 72 73 Select Y if unsure 74 75config ND_PFN 76 tristate 77 78config NVDIMM_PFN 79 bool "PFN: Map persistent (device) memory" 80 default LIBNVDIMM 81 depends on ZONE_DEVICE 82 select ND_CLAIM 83 help 84 Map persistent memory, i.e. advertise it to the memory 85 management sub-system. By default persistent memory does 86 not support direct I/O, RDMA, or any other usage that 87 requires a 'struct page' to mediate an I/O request. This 88 driver allocates and initializes the infrastructure needed 89 to support those use cases. 90 91 Select Y if unsure 92 93config NVDIMM_DAX 94 bool "NVDIMM DAX: Raw access to persistent memory" 95 default LIBNVDIMM 96 depends on NVDIMM_PFN 97 help 98 Support raw device dax access to a persistent memory 99 namespace. For environments that want to hard partition 100 persistent memory, this capability provides a mechanism to 101 sub-divide a namespace into character devices that can only be 102 accessed via DAX (mmap(2)). 103 104 Select Y if unsure 105 106config OF_PMEM 107 tristate "Device-tree support for persistent memory regions" 108 depends on OF 109 default LIBNVDIMM 110 help 111 Allows regions of persistent memory to be described in the 112 device-tree. 113 114 Select Y if unsure. 115 116config NVDIMM_KEYS 117 def_bool y 118 depends on ENCRYPTED_KEYS 119 depends on (LIBNVDIMM=ENCRYPTED_KEYS) || LIBNVDIMM=m 120 121endif 122