12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364 |
- menuconfig MTD_UBI
- tristate "Enable UBI - Unsorted block images"
- 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).
- if MTD_UBI
- config MTD_UBI_WL_THRESHOLD
- int "UBI wear-leveling threshold"
- default 4096
- range 2 65536
- 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 than 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
- 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)"
- 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.
- config MTD_UBI_DEBUG
- bool "UBI debugging"
- depends on SYSFS
- select DEBUG_FS
- select KALLSYMS
- help
- This option enables UBI debugging.
- endif # MTD_UBI
|