- Enabling this turns off the test that chunks are erased in flash
- before writing to them. This is safe, since the write verification
- will fail. Suggest enabling the test (ie. say N)
- during development to help debug things.
+ Without this, you need to explicitely use yaffs2 as the file
+ system type. With this, you can say "yaffs" and yaffs or yaffs2
+ will be used depending on the device page size (yaffs on
+ 512-byte page devices, yaffs2 on 2K page devices).
+
+ If unsure, say Y.
+
+config YAFFS_DISABLE_TAGS_ECC
+ bool "Disable YAFFS from doing ECC on tags by default"
+ depends on YAFFS_FS && YAFFS_YAFFS2
+ default n
+ help
+ This defaults Yaffs to using its own ECC calculations on tags instead of
+ just relying on the MTD.
+ This behavior can also be overridden with tags_ecc_on and
+ tags_ecc_off mount options.
+
+ If unsure, say N.
+
+
+config YAFFS_DISABLE_WIDE_TNODES
+ bool "Turn off wide tnodes"
+ depends on YAFFS_FS
+ default n
+ help
+ Wide tnodes are only used for NAND arrays >=32MB for 512-byte
+ page devices and >=128MB for 2k page devices. They use slightly
+ more RAM but are faster since they eliminate chunk group
+ searching.
+
+ Setting this to 'y' will force tnode width to 16 bits and save
+ memory but make large arrays slower.
+
+ If unsure, say N.
+
+config YAFFS_ALWAYS_CHECK_CHUNK_ERASED
+ bool "Force chunk erase check"
+ depends on YAFFS_FS
+ default n
+ help
+ Normally YAFFS only checks chunks before writing until an erased
+ chunk is found. This helps to detect any partially written
+ chunks that might have happened due to power loss.
+
+ Enabling this forces on the test that chunks are erased in flash
+ before writing to them. This takes more time but is potentially
+ a bit more secure.
+
+ Suggest setting Y during development and ironing out driver
+ issues etc. Suggest setting to N if you want faster writing.