| # 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 |
| bool "Emulate MTD devices" |
| default n |
| depends on MTD_UBI |
| help |
| This option enables MTD devices emulation 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 if no legacy software will be used. |
| |
| source "drivers/mtd/ubi/Kconfig.debug" |
| endmenu |