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Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001menu "UBI - Unsorted block images"
2 depends on MTD
3
4config MTD_UBI
5 tristate "Enable UBI"
6 depends on MTD
7 select CRC32
8 help
9 UBI is a software layer above MTD layer which admits of LVM-like
10 logical volumes on top of MTD devices, hides some complexities of
11 flash chips like wear and bad blocks and provides some other useful
12 capabilities. Please, consult the MTD web site for more details
13 (www.linux-mtd.infradead.org).
14
15config MTD_UBI_WL_THRESHOLD
16 int "UBI wear-leveling threshold"
17 default 4096
18 range 2 65536
19 depends on MTD_UBI
20 help
21 This parameter defines the maximum difference between the highest
22 erase counter value and the lowest erase counter value of eraseblocks
23 of UBI devices. When this threshold is exceeded, UBI starts performing
24 wear leveling by means of moving data from eraseblock with low erase
Artem Bityutskiy6e0c84e2008-03-27 17:18:45 +020025 counter to eraseblocks with high erase counter.
26
27 The default value should be OK for SLC NAND flashes, NOR flashes and
28 other flashes which have eraseblock life-cycle 100000 or more.
29 However, in case of MLC NAND flashes which typically have eraseblock
30 life-cycle less then 10000, the threshold should be lessened (e.g.,
31 to 128 or 256, although it does not have to be power of 2).
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +040032
33config MTD_UBI_BEB_RESERVE
34 int "Percentage of reserved eraseblocks for bad eraseblocks handling"
35 default 1
36 range 0 25
37 depends on MTD_UBI
38 help
39 If the MTD device admits of bad eraseblocks (e.g. NAND flash), UBI
40 reserves some amount of physical eraseblocks to handle new bad
41 eraseblocks. For example, if a flash physical eraseblock becomes bad,
42 UBI uses these reserved physical eraseblocks to relocate the bad one.
43 This option specifies how many physical eraseblocks will be reserved
44 for bad eraseblock handling (percents of total number of good flash
45 eraseblocks). If the underlying flash does not admit of bad
46 eraseblocks (e.g. NOR flash), this value is ignored and nothing is
47 reserved. Leave the default value if unsure.
48
49config MTD_UBI_GLUEBI
Dmitry Pervushin2ba3d762009-05-31 18:32:59 +040050 tristate "MTD devices emulation driver (gluebi)"
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +040051 default n
52 depends on MTD_UBI
53 help
Dmitry Pervushin2ba3d762009-05-31 18:32:59 +040054 This option enables gluebi - an additional driver which emulates MTD
55 devices on top of UBI volumes: for each UBI volumes an MTD device is
56 created, and all I/O to this MTD device is redirected to the UBI
57 volume. This is handy to make MTD-oriented software (like JFFS2)
58 work on top of UBI. Do not enable this unless you use legacy
59 software.
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +040060
61source "drivers/mtd/ubi/Kconfig.debug"
62endmenu