kconfig: introduce kconfig for UBI

move the UBI config options into Kconfig.

Signed-off-by: Heiko Schocher <hs@denx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Andrew F. Davis <afd@ti.com>
Reviewed by: Evgeni Dobrev <evgeni at studio-punkt.com>

1 files changed, 98 insertions, 0 deletions

diff --git a/drivers/mtd/ubi/Kconfig b/drivers/mtd/ubi/Kconfig
new file mode 100644
index 0000000000..0c82395317
--- /dev/null
+++ b/drivers/mtd/ubi/Kconfig
@@ -0,0 +1,98 @@
+menu "UBI support"
+
+config MTD_UBI
+	bool "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_LIMIT
+	int "Maximum expected bad eraseblock count per 1024 eraseblocks"
+	default 20
+	range 0 768
+	help
+	  This option specifies the maximum bad physical eraseblocks UBI
+	  expects on the MTD device (per 1024 eraseblocks). If the underlying
+	  flash does not admit of bad eraseblocks (e.g. NOR flash), this value
+	  is ignored.
+
+	  NAND datasheets often specify the minimum and maximum NVM (Number of
+	  Valid Blocks) for the flashes' endurance lifetime. The maximum
+	  expected bad eraseblocks per 1024 eraseblocks then can be calculated
+	  as "1024 * (1 - MinNVB / MaxNVB)", which gives 20 for most NANDs
+	  (MaxNVB is basically the total count of eraseblocks on the chip).
+
+	  To put it differently, if this value is 20, UBI will try to reserve
+	  about 1.9% of physical eraseblocks for bad blocks handling. And that
+	  will be 1.9% of eraseblocks on the entire NAND chip, not just the MTD
+	  partition UBI attaches. This means that if you have, say, a NAND
+	  flash chip admits maximum 40 bad eraseblocks, and it is split on two
+	  MTD partitions of the same size, UBI will reserve 40 eraseblocks when
+	  attaching a partition.
+
+	  This option can be overridden by the "mtd=" UBI module parameter or
+	  by the "attach" ioctl.
+
+	  Leave the default value if unsure.
+
+config MTD_UBI_FASTMAP
+	bool "UBI Fastmap (Experimental feature)"
+	default n
+	help
+	   Important: this feature is experimental so far and the on-flash
+	   format for fastmap may change in the next kernel versions
+
+	   Fastmap is a mechanism which allows attaching an UBI device
+	   in nearly constant time. Instead of scanning the whole MTD device it
+	   only has to locate a checkpoint (called fastmap) on the device.
+	   The on-flash fastmap contains all information needed to attach
+	   the device. Using fastmap makes only sense on large devices where
+	   attaching by scanning takes long. UBI will not automatically install
+	   a fastmap on old images, but you can set the UBI module parameter
+	   fm_autoconvert to 1 if you want so. Please note that fastmap-enabled
+	   images are still usable with UBI implementations without
+	   fastmap support. On typical flash devices the whole fastmap fits
+	   into one PEB. UBI will reserve PEBs to hold two fastmaps.
+
+	   If in doubt, say "N".
+
+config MTD_UBI_FASTMAP_AUTOCONVERT
+	int "enable UBI Fastmap autoconvert"
+	depends on MTD_UBI_FASTMAP
+	default 0
+	help
+	  Set this parameter to enable fastmap automatically on images
+	  without a fastmap.
+
+config MTD_UBI_FM_DEBUG
+	int "Enable UBI fastmap debug"
+	depends on MTD_UBI_FASTMAP
+	default 0
+	help
+	  Enable UBI fastmap debug
+
+endif # MTD_UBI
+endmenu # "Enable UBI - Unsorted block images"