xref: /linux-6.15/drivers/mtd/Kconfig (revision c5da56f7)
1menuconfig MTD
2	tristate "Memory Technology Device (MTD) support"
3	imply NVMEM
4	help
5	  Memory Technology Devices are flash, RAM and similar chips, often
6	  used for solid state file systems on embedded devices. This option
7	  will provide the generic support for MTD drivers to register
8	  themselves with the kernel and for potential users of MTD devices
9	  to enumerate the devices which are present and obtain a handle on
10	  them. It will also allow you to select individual drivers for
11	  particular hardware and users of MTD devices. If unsure, say N.
12
13if MTD
14
15config MTD_TESTS
16	tristate "MTD tests support (DANGEROUS)"
17	depends on m
18	help
19	  This option includes various MTD tests into compilation. The tests
20	  should normally be compiled as kernel modules. The modules perform
21	  various checks and verifications when loaded.
22
23	  WARNING: some of the tests will ERASE entire MTD device which they
24	  test. Do not use these tests unless you really know what you do.
25
26config MTD_CMDLINE_PARTS
27	tristate "Command line partition table parsing"
28	depends on MTD
29	help
30	  Allow generic configuration of the MTD partition tables via the kernel
31	  command line. Multiple flash resources are supported for hardware where
32	  different kinds of flash memory are available.
33
34	  You will still need the parsing functions to be called by the driver
35	  for your particular device. It won't happen automatically. The
36	  SA1100 map driver (CONFIG_MTD_SA1100) has an option for this, for
37	  example.
38
39	  The format for the command line is as follows:
40
41	  mtdparts=<mtddef>[;<mtddef]
42	  <mtddef>  := <mtd-id>:<partdef>[,<partdef>]
43	  <partdef> := <size>[@offset][<name>][ro]
44	  <mtd-id>  := unique id used in mapping driver/device
45	  <size>    := standard linux memsize OR "-" to denote all
46	  remaining space
47	  <name>    := (NAME)
48
49	  Due to the way Linux handles the command line, no spaces are
50	  allowed in the partition definition, including mtd id's and partition
51	  names.
52
53	  Examples:
54
55	  1 flash resource (mtd-id "sa1100"), with 1 single writable partition:
56	  mtdparts=sa1100:-
57
58	  Same flash, but 2 named partitions, the first one being read-only:
59	  mtdparts=sa1100:256k(ARMboot)ro,-(root)
60
61	  If unsure, say 'N'.
62
63menu "Partition parsers"
64source "drivers/mtd/parsers/Kconfig"
65endmenu
66
67comment "User Modules And Translation Layers"
68
69#
70# MTD block device support is select'ed if needed
71#
72config MTD_BLKDEVS
73	tristate
74
75config MTD_BLOCK
76	tristate "Caching block device access to MTD devices"
77	depends on BLOCK
78	select MTD_BLKDEVS
79	help
80	  Although most flash chips have an erase size too large to be useful
81	  as block devices, it is possible to use MTD devices which are based
82	  on RAM chips in this manner. This block device is a user of MTD
83	  devices performing that function.
84
85	  At the moment, it is also required for the Journalling Flash File
86	  System(s) to obtain a handle on the MTD device when it's mounted
87	  (although JFFS and JFFS2 don't actually use any of the functionality
88	  of the mtdblock device).
89
90	  Later, it may be extended to perform read/erase/modify/write cycles
91	  on flash chips to emulate a smaller block size. Needless to say,
92	  this is very unsafe, but could be useful for file systems which are
93	  almost never written to.
94
95	  You do not need this option for use with the DiskOnChip devices. For
96	  those, enable NFTL support (CONFIG_NFTL) instead.
97
98config MTD_BLOCK_RO
99	tristate "Readonly block device access to MTD devices"
100	depends on MTD_BLOCK!=y && BLOCK
101	select MTD_BLKDEVS
102	help
103	  This allows you to mount read-only file systems (such as cramfs)
104	  from an MTD device, without the overhead (and danger) of the caching
105	  driver.
106
107	  You do not need this option for use with the DiskOnChip devices. For
108	  those, enable NFTL support (CONFIG_NFTL) instead.
109
110config FTL
111	tristate "FTL (Flash Translation Layer) support"
112	depends on BLOCK
113	select MTD_BLKDEVS
114	help
115	  This provides support for the original Flash Translation Layer which
116	  is part of the PCMCIA specification. It uses a kind of pseudo-
117	  file system on a flash device to emulate a block device with
118	  512-byte sectors, on top of which you put a 'normal' file system.
119
120	  You may find that the algorithms used in this code are patented
121	  unless you live in the Free World where software patents aren't
122	  legal - in the USA you are only permitted to use this on PCMCIA
123	  hardware, although under the terms of the GPL you're obviously
124	  permitted to copy, modify and distribute the code as you wish. Just
125	  not use it.
126
127config NFTL
128	tristate "NFTL (NAND Flash Translation Layer) support"
129	depends on BLOCK
130	select MTD_BLKDEVS
131	help
132	  This provides support for the NAND Flash Translation Layer which is
133	  used on M-Systems' DiskOnChip devices. It uses a kind of pseudo-
134	  file system on a flash device to emulate a block device with
135	  512-byte sectors, on top of which you put a 'normal' file system.
136
137	  You may find that the algorithms used in this code are patented
138	  unless you live in the Free World where software patents aren't
139	  legal - in the USA you are only permitted to use this on DiskOnChip
140	  hardware, although under the terms of the GPL you're obviously
141	  permitted to copy, modify and distribute the code as you wish. Just
142	  not use it.
143
144config NFTL_RW
145	bool "Write support for NFTL"
146	depends on NFTL
147	help
148	  Support for writing to the NAND Flash Translation Layer, as used
149	  on the DiskOnChip.
150
151config INFTL
152	tristate "INFTL (Inverse NAND Flash Translation Layer) support"
153	depends on BLOCK
154	select MTD_BLKDEVS
155	help
156	  This provides support for the Inverse NAND Flash Translation
157	  Layer which is used on M-Systems' newer DiskOnChip devices. It
158	  uses a kind of pseudo-file system on a flash device to emulate
159	  a block device with 512-byte sectors, on top of which you put
160	  a 'normal' file system.
161
162	  You may find that the algorithms used in this code are patented
163	  unless you live in the Free World where software patents aren't
164	  legal - in the USA you are only permitted to use this on DiskOnChip
165	  hardware, although under the terms of the GPL you're obviously
166	  permitted to copy, modify and distribute the code as you wish. Just
167	  not use it.
168
169config RFD_FTL
170	tristate "Resident Flash Disk (Flash Translation Layer) support"
171	depends on BLOCK
172	select MTD_BLKDEVS
173	help
174	  This provides support for the flash translation layer known
175	  as the Resident Flash Disk (RFD), as used by the Embedded BIOS
176	  of General Software. There is a blurb at:
177
178		http://www.gensw.com/pages/prod/bios/rfd.htm
179
180config SSFDC
181	tristate "NAND SSFDC (SmartMedia) read only translation layer"
182	depends on BLOCK
183	select MTD_BLKDEVS
184	help
185	  This enables read only access to SmartMedia formatted NAND
186	  flash. You can mount it with FAT file system.
187
188config SM_FTL
189	tristate "SmartMedia/xD new translation layer"
190	depends on BLOCK
191	select MTD_BLKDEVS
192	select MTD_NAND_ECC_SW_HAMMING
193	help
194	  This enables EXPERIMENTAL R/W support for SmartMedia/xD
195	  FTL (Flash translation layer).
196	  Write support is only lightly tested, therefore this driver
197	  isn't recommended to use with valuable data (anyway if you have
198	  valuable data, do backups regardless of software/hardware you
199	  use, because you never know what will eat your data...)
200	  If you only need R/O access, you can use older R/O driver
201	  (CONFIG_SSFDC)
202
203config MTD_OOPS
204	tristate "Log panic/oops to an MTD buffer"
205	help
206	  This enables panic and oops messages to be logged to a circular
207	  buffer in a flash partition where it can be read back at some
208	  later point.
209
210config MTD_SWAP
211	tristate "Swap on MTD device support"
212	depends on MTD && SWAP
213	select MTD_BLKDEVS
214	help
215	  Provides volatile block device driver on top of mtd partition
216	  suitable for swapping.  The mapping of written blocks is not saved.
217	  The driver provides wear leveling by storing erase counter into the
218	  OOB.
219
220config MTD_PARTITIONED_MASTER
221	bool "Retain master device when partitioned"
222	default n
223	depends on MTD
224	help
225	  For historical reasons, by default, either a master is present or
226	  several partitions are present, but not both. The concern was that
227	  data listed in multiple partitions was dangerous; however, SCSI does
228	  this and it is frequently useful for applications. This config option
229	  leaves the master in even if the device is partitioned. It also makes
230	  the parent of the partition device be the master device, rather than
231	  what lies behind the master.
232
233source "drivers/mtd/chips/Kconfig"
234
235source "drivers/mtd/maps/Kconfig"
236
237source "drivers/mtd/devices/Kconfig"
238
239source "drivers/mtd/nand/Kconfig"
240
241source "drivers/mtd/lpddr/Kconfig"
242
243source "drivers/mtd/spi-nor/Kconfig"
244
245source "drivers/mtd/ubi/Kconfig"
246
247source "drivers/mtd/hyperbus/Kconfig"
248
249endif # MTD
250