xref: /openbmc/linux/drivers/mtd/Kconfig (revision e021ae7f)
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
26menu "Partition parsers"
27source "drivers/mtd/parsers/Kconfig"
28endmenu
29
30comment "User Modules And Translation Layers"
31
32#
33# MTD block device support is select'ed if needed
34#
35config MTD_BLKDEVS
36	tristate
37
38config MTD_BLOCK
39	tristate "Caching block device access to MTD devices"
40	depends on BLOCK
41	select MTD_BLKDEVS
42	help
43	  Although most flash chips have an erase size too large to be useful
44	  as block devices, it is possible to use MTD devices which are based
45	  on RAM chips in this manner. This block device is a user of MTD
46	  devices performing that function.
47
48	  Note that mounting a JFFS2 filesystem doesn't require using mtdblock.
49	  It's possible to mount a rootfs using the MTD device on the "root="
50	  bootargs as "root=mtd2" or "root=mtd:name_of_device".
51
52	  Later, it may be extended to perform read/erase/modify/write cycles
53	  on flash chips to emulate a smaller block size. Needless to say,
54	  this is very unsafe, but could be useful for file systems which are
55	  almost never written to.
56
57	  You do not need this option for use with the DiskOnChip devices. For
58	  those, enable NFTL support (CONFIG_NFTL) instead.
59
60config MTD_BLOCK_RO
61	tristate "Readonly block device access to MTD devices"
62	depends on MTD_BLOCK!=y && BLOCK
63	select MTD_BLKDEVS
64	help
65	  This allows you to mount read-only file systems (such as cramfs)
66	  from an MTD device, without the overhead (and danger) of the caching
67	  driver.
68
69	  You do not need this option for use with the DiskOnChip devices. For
70	  those, enable NFTL support (CONFIG_NFTL) instead.
71
72comment "Note that in some cases UBI block is preferred. See MTD_UBI_BLOCK."
73	depends on MTD_BLOCK || MTD_BLOCK_RO
74
75config FTL
76	tristate "FTL (Flash Translation Layer) support"
77	depends on BLOCK
78	select MTD_BLKDEVS
79	help
80	  This provides support for the original Flash Translation Layer which
81	  is part of the PCMCIA specification. It uses a kind of pseudo-
82	  file system on a flash device to emulate a block device with
83	  512-byte sectors, on top of which you put a 'normal' file system.
84
85	  You may find that the algorithms used in this code are patented
86	  unless you live in the Free World where software patents aren't
87	  legal - in the USA you are only permitted to use this on PCMCIA
88	  hardware, although under the terms of the GPL you're obviously
89	  permitted to copy, modify and distribute the code as you wish. Just
90	  not use it.
91
92config NFTL
93	tristate "NFTL (NAND Flash Translation Layer) support"
94	depends on BLOCK
95	select MTD_BLKDEVS
96	help
97	  This provides support for the NAND Flash Translation Layer which is
98	  used on M-Systems' DiskOnChip devices. It uses a kind of pseudo-
99	  file system on a flash device to emulate a block device with
100	  512-byte sectors, on top of which you put a 'normal' file system.
101
102	  You may find that the algorithms used in this code are patented
103	  unless you live in the Free World where software patents aren't
104	  legal - in the USA you are only permitted to use this on DiskOnChip
105	  hardware, although under the terms of the GPL you're obviously
106	  permitted to copy, modify and distribute the code as you wish. Just
107	  not use it.
108
109config NFTL_RW
110	bool "Write support for NFTL"
111	depends on NFTL
112	help
113	  Support for writing to the NAND Flash Translation Layer, as used
114	  on the DiskOnChip.
115
116config INFTL
117	tristate "INFTL (Inverse NAND Flash Translation Layer) support"
118	depends on BLOCK
119	select MTD_BLKDEVS
120	help
121	  This provides support for the Inverse NAND Flash Translation
122	  Layer which is used on M-Systems' newer DiskOnChip devices. It
123	  uses a kind of pseudo-file system on a flash device to emulate
124	  a block device with 512-byte sectors, on top of which you put
125	  a 'normal' file system.
126
127	  You may find that the algorithms used in this code are patented
128	  unless you live in the Free World where software patents aren't
129	  legal - in the USA you are only permitted to use this on DiskOnChip
130	  hardware, although under the terms of the GPL you're obviously
131	  permitted to copy, modify and distribute the code as you wish. Just
132	  not use it.
133
134config RFD_FTL
135	tristate "Resident Flash Disk (Flash Translation Layer) support"
136	depends on BLOCK
137	select MTD_BLKDEVS
138	help
139	  This provides support for the flash translation layer known
140	  as the Resident Flash Disk (RFD), as used by the Embedded BIOS
141	  of General Software. There is a blurb at:
142
143		http://www.gensw.com/pages/prod/bios/rfd.htm
144
145config SSFDC
146	tristate "NAND SSFDC (SmartMedia) read only translation layer"
147	depends on BLOCK
148	select MTD_BLKDEVS
149	help
150	  This enables read only access to SmartMedia formatted NAND
151	  flash. You can mount it with FAT file system.
152
153config SM_FTL
154	tristate "SmartMedia/xD new translation layer"
155	depends on BLOCK
156	select MTD_BLKDEVS
157	select MTD_NAND_CORE
158	select MTD_NAND_ECC_SW_HAMMING
159	help
160	  This enables EXPERIMENTAL R/W support for SmartMedia/xD
161	  FTL (Flash translation layer).
162	  Write support is only lightly tested, therefore this driver
163	  isn't recommended to use with valuable data (anyway if you have
164	  valuable data, do backups regardless of software/hardware you
165	  use, because you never know what will eat your data...)
166	  If you only need R/O access, you can use older R/O driver
167	  (CONFIG_SSFDC)
168
169config MTD_OOPS
170	tristate "Log panic/oops to an MTD buffer"
171	help
172	  This enables panic and oops messages to be logged to a circular
173	  buffer in a flash partition where it can be read back at some
174	  later point.
175
176config MTD_PSTORE
177	tristate "Log panic/oops to an MTD buffer based on pstore"
178	depends on PSTORE_BLK
179	help
180	  This enables panic and oops messages to be logged to a circular
181	  buffer in a flash partition where it can be read back as files after
182	  mounting pstore filesystem.
183
184	  If unsure, say N.
185
186config MTD_SWAP
187	tristate "Swap on MTD device support"
188	depends on MTD && SWAP
189	select MTD_BLKDEVS
190	help
191	  Provides volatile block device driver on top of mtd partition
192	  suitable for swapping.  The mapping of written blocks is not saved.
193	  The driver provides wear leveling by storing erase counter into the
194	  OOB.
195
196config MTD_PARTITIONED_MASTER
197	bool "Retain master device when partitioned"
198	default n
199	depends on MTD
200	help
201	  For historical reasons, by default, either a master is present or
202	  several partitions are present, but not both. The concern was that
203	  data listed in multiple partitions was dangerous; however, SCSI does
204	  this and it is frequently useful for applications. This config option
205	  leaves the master in even if the device is partitioned. It also makes
206	  the parent of the partition device be the master device, rather than
207	  what lies behind the master.
208
209source "drivers/mtd/chips/Kconfig"
210
211source "drivers/mtd/maps/Kconfig"
212
213source "drivers/mtd/devices/Kconfig"
214
215source "drivers/mtd/nand/Kconfig"
216
217source "drivers/mtd/lpddr/Kconfig"
218
219source "drivers/mtd/spi-nor/Kconfig"
220
221source "drivers/mtd/ubi/Kconfig"
222
223source "drivers/mtd/hyperbus/Kconfig"
224
225endif # MTD
226