xref: /openbmc/linux/drivers/mtd/Kconfig (revision f15cbe6f)
1menuconfig MTD
2	tristate "Memory Technology Device (MTD) support"
3	depends on HAS_IOMEM
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_DEBUG
16	bool "Debugging"
17	help
18	  This turns on low-level debugging for the entire MTD sub-system.
19	  Normally, you should say 'N'.
20
21config MTD_DEBUG_VERBOSE
22	int "Debugging verbosity (0 = quiet, 3 = noisy)"
23	depends on MTD_DEBUG
24	default "0"
25	help
26	  Determines the verbosity level of the MTD debugging messages.
27
28config MTD_CONCAT
29	tristate "MTD concatenating support"
30	help
31	  Support for concatenating several MTD devices into a single
32	  (virtual) one. This allows you to have -for example- a JFFS(2)
33	  file system spanning multiple physical flash chips. If unsure,
34	  say 'Y'.
35
36config MTD_PARTITIONS
37	bool "MTD partitioning support"
38	help
39	  If you have a device which needs to divide its flash chip(s) up
40	  into multiple 'partitions', each of which appears to the user as
41	  a separate MTD device, you require this option to be enabled. If
42	  unsure, say 'Y'.
43
44	  Note, however, that you don't need this option for the DiskOnChip
45	  devices. Partitioning on NFTL 'devices' is a different - that's the
46	  'normal' form of partitioning used on a block device.
47
48config MTD_REDBOOT_PARTS
49	tristate "RedBoot partition table parsing"
50	depends on MTD_PARTITIONS
51	---help---
52	  RedBoot is a ROM monitor and bootloader which deals with multiple
53	  'images' in flash devices by putting a table one of the erase
54	  blocks on the device, similar to a partition table, which gives
55	  the offsets, lengths and names of all the images stored in the
56	  flash.
57
58	  If you need code which can detect and parse this table, and register
59	  MTD 'partitions' corresponding to each image in the table, enable
60	  this option.
61
62	  You will still need the parsing functions to be called by the driver
63	  for your particular device. It won't happen automatically. The
64	  SA1100 map driver (CONFIG_MTD_SA1100) has an option for this, for
65	  example.
66
67config MTD_REDBOOT_DIRECTORY_BLOCK
68	int "Location of RedBoot partition table"
69	depends on MTD_REDBOOT_PARTS
70	default "-1"
71	---help---
72	  This option is the Linux counterpart to the
73	  CYGNUM_REDBOOT_FIS_DIRECTORY_BLOCK RedBoot compile time
74	  option.
75
76	  The option specifies which Flash sectors holds the RedBoot
77	  partition table.  A zero or positive value gives an absolute
78	  erase block number. A negative value specifies a number of
79	  sectors before the end of the device.
80
81	  For example "2" means block number 2, "-1" means the last
82	  block and "-2" means the penultimate block.
83
84config MTD_REDBOOT_PARTS_UNALLOCATED
85	bool "Include unallocated flash regions"
86	depends on MTD_REDBOOT_PARTS
87	help
88	  If you need to register each unallocated flash region as a MTD
89	  'partition', enable this option.
90
91config MTD_REDBOOT_PARTS_READONLY
92	bool "Force read-only for RedBoot system images"
93	depends on MTD_REDBOOT_PARTS
94	help
95	  If you need to force read-only for 'RedBoot', 'RedBoot Config' and
96	  'FIS directory' images, enable this option.
97
98config MTD_CMDLINE_PARTS
99	bool "Command line partition table parsing"
100	depends on MTD_PARTITIONS = "y" && MTD = "y"
101	---help---
102	  Allow generic configuration of the MTD partition tables via the kernel
103	  command line. Multiple flash resources are supported for hardware where
104	  different kinds of flash memory are available.
105
106	  You will still need the parsing functions to be called by the driver
107	  for your particular device. It won't happen automatically. The
108	  SA1100 map driver (CONFIG_MTD_SA1100) has an option for this, for
109	  example.
110
111	  The format for the command line is as follows:
112
113	  mtdparts=<mtddef>[;<mtddef]
114	  <mtddef>  := <mtd-id>:<partdef>[,<partdef>]
115	  <partdef> := <size>[@offset][<name>][ro]
116	  <mtd-id>  := unique id used in mapping driver/device
117	  <size>    := standard linux memsize OR "-" to denote all
118	  remaining space
119	  <name>    := (NAME)
120
121	  Due to the way Linux handles the command line, no spaces are
122	  allowed in the partition definition, including mtd id's and partition
123	  names.
124
125	  Examples:
126
127	  1 flash resource (mtd-id "sa1100"), with 1 single writable partition:
128	  mtdparts=sa1100:-
129
130	  Same flash, but 2 named partitions, the first one being read-only:
131	  mtdparts=sa1100:256k(ARMboot)ro,-(root)
132
133	  If unsure, say 'N'.
134
135config MTD_AFS_PARTS
136	tristate "ARM Firmware Suite partition parsing"
137	depends on ARM && MTD_PARTITIONS
138	---help---
139	  The ARM Firmware Suite allows the user to divide flash devices into
140	  multiple 'images'. Each such image has a header containing its name
141	  and offset/size etc.
142
143	  If you need code which can detect and parse these tables, and
144	  register MTD 'partitions' corresponding to each image detected,
145	  enable this option.
146
147	  You will still need the parsing functions to be called by the driver
148	  for your particular device. It won't happen automatically. The
149	  'armflash' map driver (CONFIG_MTD_ARMFLASH) does this, for example.
150
151config MTD_OF_PARTS
152	tristate "Flash partition map based on OF description"
153	depends on PPC_OF && MTD_PARTITIONS
154	help
155	  This provides a partition parsing function which derives
156	  the partition map from the children of the flash node,
157	  as described in Documentation/powerpc/booting-without-of.txt.
158
159config MTD_AR7_PARTS
160	tristate "TI AR7 partitioning support"
161	depends on MTD_PARTITIONS
162	---help---
163	  TI AR7 partitioning support
164
165comment "User Modules And Translation Layers"
166
167config MTD_CHAR
168	tristate "Direct char device access to MTD devices"
169	help
170	  This provides a character device for each MTD device present in
171	  the system, allowing the user to read and write directly to the
172	  memory chips, and also use ioctl() to obtain information about
173	  the device, or to erase parts of it.
174
175config MTD_BLKDEVS
176	tristate "Common interface to block layer for MTD 'translation layers'"
177	depends on BLOCK
178	default n
179
180config MTD_BLOCK
181	tristate "Caching block device access to MTD devices"
182	depends on BLOCK
183	select MTD_BLKDEVS
184	---help---
185	  Although most flash chips have an erase size too large to be useful
186	  as block devices, it is possible to use MTD devices which are based
187	  on RAM chips in this manner. This block device is a user of MTD
188	  devices performing that function.
189
190	  At the moment, it is also required for the Journalling Flash File
191	  System(s) to obtain a handle on the MTD device when it's mounted
192	  (although JFFS and JFFS2 don't actually use any of the functionality
193	  of the mtdblock device).
194
195	  Later, it may be extended to perform read/erase/modify/write cycles
196	  on flash chips to emulate a smaller block size. Needless to say,
197	  this is very unsafe, but could be useful for file systems which are
198	  almost never written to.
199
200	  You do not need this option for use with the DiskOnChip devices. For
201	  those, enable NFTL support (CONFIG_NFTL) instead.
202
203config MTD_BLOCK_RO
204	tristate "Readonly block device access to MTD devices"
205	depends on MTD_BLOCK!=y && BLOCK
206	select MTD_BLKDEVS
207	help
208	  This allows you to mount read-only file systems (such as cramfs)
209	  from an MTD device, without the overhead (and danger) of the caching
210	  driver.
211
212	  You do not need this option for use with the DiskOnChip devices. For
213	  those, enable NFTL support (CONFIG_NFTL) instead.
214
215config FTL
216	tristate "FTL (Flash Translation Layer) support"
217	depends on BLOCK
218	select MTD_BLKDEVS
219	---help---
220	  This provides support for the original Flash Translation Layer which
221	  is part of the PCMCIA specification. It uses a kind of pseudo-
222	  file system on a flash device to emulate a block device with
223	  512-byte sectors, on top of which you put a 'normal' file system.
224
225	  You may find that the algorithms used in this code are patented
226	  unless you live in the Free World where software patents aren't
227	  legal - in the USA you are only permitted to use this on PCMCIA
228	  hardware, although under the terms of the GPL you're obviously
229	  permitted to copy, modify and distribute the code as you wish. Just
230	  not use it.
231
232config NFTL
233	tristate "NFTL (NAND Flash Translation Layer) support"
234	depends on BLOCK
235	select MTD_BLKDEVS
236	---help---
237	  This provides support for the NAND Flash Translation Layer which is
238	  used on M-Systems' DiskOnChip devices. It uses a kind of pseudo-
239	  file system on a flash device to emulate a block device with
240	  512-byte sectors, on top of which you put a 'normal' file system.
241
242	  You may find that the algorithms used in this code are patented
243	  unless you live in the Free World where software patents aren't
244	  legal - in the USA you are only permitted to use this on DiskOnChip
245	  hardware, although under the terms of the GPL you're obviously
246	  permitted to copy, modify and distribute the code as you wish. Just
247	  not use it.
248
249config NFTL_RW
250	bool "Write support for NFTL"
251	depends on NFTL
252	help
253	  Support for writing to the NAND Flash Translation Layer, as used
254	  on the DiskOnChip.
255
256config INFTL
257	tristate "INFTL (Inverse NAND Flash Translation Layer) support"
258	depends on BLOCK
259	select MTD_BLKDEVS
260	---help---
261	  This provides support for the Inverse NAND Flash Translation
262	  Layer which is used on M-Systems' newer DiskOnChip devices. It
263	  uses a kind of pseudo-file system on a flash device to emulate
264	  a block device with 512-byte sectors, on top of which you put
265	  a 'normal' file system.
266
267	  You may find that the algorithms used in this code are patented
268	  unless you live in the Free World where software patents aren't
269	  legal - in the USA you are only permitted to use this on DiskOnChip
270	  hardware, although under the terms of the GPL you're obviously
271	  permitted to copy, modify and distribute the code as you wish. Just
272	  not use it.
273
274config RFD_FTL
275        tristate "Resident Flash Disk (Flash Translation Layer) support"
276	depends on BLOCK
277	select MTD_BLKDEVS
278	---help---
279	  This provides support for the flash translation layer known
280	  as the Resident Flash Disk (RFD), as used by the Embedded BIOS
281	  of General Software. There is a blurb at:
282
283		http://www.gensw.com/pages/prod/bios/rfd.htm
284
285config SSFDC
286	tristate "NAND SSFDC (SmartMedia) read only translation layer"
287	depends on BLOCK
288	select MTD_BLKDEVS
289	help
290	  This enables read only access to SmartMedia formatted NAND
291	  flash. You can mount it with FAT file system.
292
293config MTD_OOPS
294	tristate "Log panic/oops to an MTD buffer"
295	depends on MTD
296	help
297	  This enables panic and oops messages to be logged to a circular
298	  buffer in a flash partition where it can be read back at some
299	  later point.
300
301	  To use, add console=ttyMTDx to the kernel command line,
302	  where x is the MTD device number to use.
303
304source "drivers/mtd/chips/Kconfig"
305
306source "drivers/mtd/maps/Kconfig"
307
308source "drivers/mtd/devices/Kconfig"
309
310source "drivers/mtd/nand/Kconfig"
311
312source "drivers/mtd/onenand/Kconfig"
313
314source "drivers/mtd/ubi/Kconfig"
315
316endif # MTD
317