drivers/mtd/ubi/Kconfig

   1 menuconfig MTD_UBI
   2         tristate "Enable UBI - Unsorted block images"
   3         select CRC32
   4         help
   5           UBI is a software layer above MTD layer which admits of LVM-like
   6           logical volumes on top of MTD devices, hides some complexities of
   7           flash chips like wear and bad blocks and provides some other useful
   8           capabilities. Please, consult the MTD web site for more details
   9           (www.linux-mtd.infradead.org).
  10
  11 if MTD_UBI
  12
  13 config MTD_UBI_WL_THRESHOLD
  14         int "UBI wear-leveling threshold"
  15         default 4096
  16         range 2 65536
  17         help
  18           This parameter defines the maximum difference between the highest
  19           erase counter value and the lowest erase counter value of eraseblocks
  20           of UBI devices. When this threshold is exceeded, UBI starts performing
  21           wear leveling by means of moving data from eraseblock with low erase
  22           counter to eraseblocks with high erase counter.
  23
  24           The default value should be OK for SLC NAND flashes, NOR flashes and
  25           other flashes which have eraseblock life-cycle 100000 or more.
  26           However, in case of MLC NAND flashes which typically have eraseblock
  27           life-cycle less than 10000, the threshold should be lessened (e.g.,
  28           to 128 or 256, although it does not have to be power of 2).
  29
  30 config MTD_UBI_BEB_RESERVE
  31         int "Percentage of reserved eraseblocks for bad eraseblocks handling"
  32         default 1
  33         range 0 25
  34         help
  35           If the MTD device admits of bad eraseblocks (e.g. NAND flash), UBI
  36           reserves some amount of physical eraseblocks to handle new bad
  37           eraseblocks. For example, if a flash physical eraseblock becomes bad,
  38           UBI uses these reserved physical eraseblocks to relocate the bad one.
  39           This option specifies how many physical eraseblocks will be reserved
  40           for bad eraseblock handling (percents of total number of good flash
  41           eraseblocks). If the underlying flash does not admit of bad
  42           eraseblocks (e.g. NOR flash), this value is ignored and nothing is
  43           reserved. Leave the default value if unsure.
  44
  45 config MTD_UBI_GLUEBI
  46         tristate "MTD devices emulation driver (gluebi)"
  47         help
  48            This option enables gluebi - an additional driver which emulates MTD
  49            devices on top of UBI volumes: for each UBI volumes an MTD device is
  50            created, and all I/O to this MTD device is redirected to the UBI
  51            volume. This is handy to make MTD-oriented software (like JFFS2)
  52            work on top of UBI. Do not enable this unless you use legacy
  53            software.
  54
  55 config MTD_UBI_DEBUG
  56         bool "UBI debugging"
  57         depends on SYSFS
  58         select DEBUG_FS
  59         select KALLSYMS
  60         help
  61           This option enables UBI debugging.
  62
  63 endif # MTD_UBI