# drivers/mtd/ubi/Kconfig

menu "UBI - Unsorted block images"
	depends on MTD

config MTD_UBI
	tristate "Enable UBI"
	depends on MTD
	select CRC32
	help
	  UBI is a software layer above MTD layer which admits of LVM-like
	  logical volumes on top of MTD devices, hides some complexities of
	  flash chips like wear and bad blocks and provides some other useful
	  capabilities. Please, consult the MTD web site for more details
	  (www.linux-mtd.infradead.org).

config MTD_UBI_WL_THRESHOLD
	int "UBI wear-leveling threshold"
	default 4096
	range 2 65536
	depends on MTD_UBI
	help
	  This parameter defines the maximum difference between the highest
	  erase counter value and the lowest erase counter value of eraseblocks
	  of UBI devices. When this threshold is exceeded, UBI starts performing
	  wear leveling by means of moving data from eraseblock with low erase
	  counter to eraseblocks with high erase counter.

	  The default value should be OK for SLC NAND flashes, NOR flashes and
	  other flashes which have eraseblock life-cycle 100000 or more.
	  However, in case of MLC NAND flashes which typically have eraseblock
	  life-cycle less then 10000, the threshold should be lessened (e.g.,
	  to 128 or 256, although it does not have to be power of 2).

config MTD_UBI_BEB_RESERVE
	int "Percentage of reserved eraseblocks for bad eraseblocks handling"
	default 1
	range 0 25
	depends on MTD_UBI
	help
	  If the MTD device admits of bad eraseblocks (e.g. NAND flash), UBI
	  reserves some amount of physical eraseblocks to handle new bad
	  eraseblocks. For example, if a flash physical eraseblock becomes bad,
	  UBI uses these reserved physical eraseblocks to relocate the bad one.
	  This option specifies how many physical eraseblocks will be reserved
	  for bad eraseblock handling (percents of total number of good flash
	  eraseblocks). If the underlying flash does not admit of bad
	  eraseblocks (e.g. NOR flash), this value is ignored and nothing is
	  reserved. Leave the default value if unsure.

config MTD_UBI_GLUEBI
	tristate "MTD devices emulation driver (gluebi)"
	default n
	depends on MTD_UBI
	help
	   This option enables gluebi - an additional driver which emulates MTD
	   devices on top of UBI volumes: for each UBI volumes an MTD device is
	   created, and all I/O to this MTD device is redirected to the UBI
	   volume. This is handy to make MTD-oriented software (like JFFS2)
	   work on top of UBI. Do not enable this unless you use legacy
	   software.

source "drivers/mtd/ubi/Kconfig.debug"
endmenu