X-Git-Url: http://www.aleph1.co.uk/gitweb/?p=yaffs2.git;a=blobdiff_plain;f=Kconfig;fp=Kconfig;h=6bd1a6b7f5f0bf59a5658e40d7bee1317a65539a;hp=dd330790c2501c723e2cccb5b36059d5e7b90e51;hb=6f1de4473200f31d1ca1cf4672baf7afcdec2db0;hpb=170ea32c52fd2d9b7cbda9b169ad44038b1d15cf diff --git a/Kconfig b/Kconfig index dd33079..6bd1a6b 100644 --- a/Kconfig +++ b/Kconfig @@ -12,8 +12,8 @@ config YAFFS_FS YAFFS2, or Yet Another Flash Filing System, is a filing system optimised for NAND Flash chips. - To compile the YAFFS2 file system support as a module, choose M here: - the module will be called yaffs2. + To compile the YAFFS2 file system support as a module, choose M + here: the module will be called yaffs2. If unsure, say N. @@ -26,6 +26,8 @@ config YAFFS_YAFFS1 default y help Enable YAFFS1 support -- yaffs for 512 byte / page devices + + Not needed for 2K-page devices. If unsure, say Y. @@ -44,9 +46,9 @@ config YAFFS_ECC_WRONG_ORDER depends on YAFFS_FS && YAFFS_DOES_ECC default n help - This makes yaffs_ecc.c use the same ecc byte order as - Steven Hill's nand_ecc.c. If not set, then you get the - same ecc byte order as SmartMedia. + This makes yaffs_ecc.c use the same ecc byte order as Steven + Hill's nand_ecc.c. If not set, then you get the same ecc byte + order as SmartMedia. If unsure, say N. @@ -55,7 +57,7 @@ config YAFFS_YAFFS2 depends on YAFFS_FS default y help - Enable YAFFS2 support -- yaffs for >= 2048 byte / page larger devices + Enable YAFFS2 support -- yaffs for >= 2K bytes per page devices If unsure, say Y. @@ -66,7 +68,8 @@ config YAFFS_AUTO_YAFFS2 help 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. + will be used depending on the device page size (yaffs on + 512-byte page devices, yaffs2 on 2K page devices). If unsure, say Y. @@ -95,31 +98,34 @@ config YAFFS_CHECKPOINT_RESERVED_BLOCKS depends on YAFFS_YAFFS2 default 10 help - Give the number of Blocks to reserve for checkpointing. These Blocks - are reserved per partition, so if you have very small partitions the - default (10) may be a mess for you. - You can set this value to 0, but that does not mean checkpointing is - disabled at all. There only won't be any specially reserved blocks for - checkpointing, so if there is enough free space on the filesystem, - it will be used for checkpointing. - - If unsure, leave at default (10), but don't wonder if there are always - 2MB used on your large page device partition (10 x 2k pagesize). When - using small partitions or when being very small on space, you probably - want to set this to zero. + Give the number of Blocks to reserve for checkpointing. + Checkpointing saves the state at unmount so that mounting is + much faster as a scan of all the flash to regenerate this state + is not needed. These Blocks are reserved per partition, so if + you have very small partitions the default (10) may be a mess + for you. You can set this value to 0, but that does not mean + checkpointing is disabled at all. There only won't be any + specially reserved blocks for checkpointing, so if there is + enough free space on the filesystem, it will be used for + checkpointing. + + If unsure, leave at default (10), but don't wonder if there are + always 2MB used on your large page device partition (10 x 2k + pagesize). When using small partitions or when being very small + on space, you probably want to set this to zero. config YAFFS_DISABLE_WIDE_TNODES bool "Turn off wide tnodes" depends on YAFFS_FS default n help - Wide tnodes are only used for large 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 + 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 make - large arrays slower. + Setting this to 'y' will force tnode width to 16 bits and save + memory but make large arrays slower. If unsure, say N. @@ -129,15 +135,15 @@ config YAFFS_ALWAYS_CHECK_CHUNK_ERASED 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. + 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. + 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. + Suggest setting Y during development and ironing out driver + issues etc. Suggest setting to N if you want faster writing. If unsure, say Y.