CONFIG_MTD_CFI
  The Common Flash Interface specification was developed by Intel,
  AMD and other flash manufactures that provides a universal method
  for probing the capabilities of flash devices. If you wish to
  support any device that is CFI-compliant, you need to enable this
  option. Visit <http://www.amd.com/products/nvd/overview/cfi.html>
  for more information on CFI.

CONFIG_MTD_CFI_ADV_OPTIONS
  If you need to specify a specific endianness for access to flash
  chips, or if you wish to reduce the size of the kernel by including
  support for only specific arrangements of flash chips, say 'Y'. This
  option does not directly affect the code, but will enable other 
  configuration options which allow you to do so.

  If unsure, say 'N'.

CONFIG_MTD_CFI_GEOMETRY
  This option does not affect the code directly, but will enable 
  some other configuration options which would allow you to reduce
  the size of the kernel by including support for only certain 
  arrangements of CFI chips. If unsure, say 'N' and all options 
  which are supported by the current code will be enabled.

CONFIG_MTD_CFI_B1
  If you wish to support CFI devices on a physical bus which is
  8 bits wide, say 'Y'.

CONFIG_MTD_CFI_B2
  If you wish to support CFI devices on a physical bus which is
  16 bits wide, say 'Y'.

CONFIG_MTD_CFI_B4
  If you wish to support CFI devices on a physical bus which is
  32 bits wide, say 'Y'.

CONFIG_MTD_CFI_I1
  If your flash chips are not interleaved - i.e. you only have one
  flash chip addressed by each bus cycle, then say 'Y'.

CONFIG_MTD_CFI_I2
  If your flash chips are interleaved in pairs - i.e. you have two
  flash chips addressed by each bus cycle, then say 'Y'.

CONFIG_MTD_CFI_I4
  If your flash chips are interleaved in fours - i.e. you have four
  flash chips addressed by each bus cycle, then say 'Y'.

CONFIG_MTD_CFI_NOSWAP
  This option defines the way in which the CPU attempts to arrange
  data bits when writing the 'magic' commands to the chips. Saying
  'NO', which is the default when CONFIG_MTD_CFI_ADV_OPTIONS isn't
  enabled, means that the CPU will not do any swapping; the chips
  are expected to be wired to the CPU in 'host-endian' form. 
  Specific arrangements are possible with the BIG_ENDIAN_BYTE and
  LITTLE_ENDIAN_BYTE, if the bytes are reversed.

  If you have a LART, on which the data (and address) lines were
  connected in a fashion which ensured that the nets were as short
  as possible, resulting in a bit-shuffling which seems utterly
  random to the untrained eye, you need the LART_ENDIAN_BYTE option.

  Yes, there really exists something sicker than PDP-endian :)

CONFIG_MTD_CFI_INTELEXT
  The Common Flash Interface defines a number of different command
  sets which a CFI-compliant chip may claim to implement. This code
  provides support for one of those command sets, used on Intel
  StrataFlash and other parts.

CONFIG_MTD_CFI_AMDSTD
  The Common Flash Interface defines a number of different command
  sets which a CFI-compliant chip may claim to implement. This code
  provides support for one of those command sets, used on chips 
  chips including the AMD Am29LV320.

CONFIG_MTD_SHARP
  This option enables support for flash chips using Sharp-compatible
  commands, including some which are not CFI-compatible and hence 
  cannot be used with the CONFIG_MTD_CFI_INTELxxx options.

CONFIG_MTD_AMDSTD
  This option enables support for flash chips using AMD-compatible
  commands, including some which are not CFI-compatible and hence 
  cannot be used with the CONFIG_MTD_CFI_AMDSTD option.

  It also works on AMD compatible chips that do conform to CFI.

CONFIG_MTD_RAM
  This option enables basic support for RAM chips accessed through 
  a bus mapping driver.

CONFIG_MTD_ROM
  This option enables basic support for ROM chips accessed through 
  a bus mapping driver.

CONFIG_MTD_JEDEC
  Enable older older JEDEC flash interface devices for self
  programming flash.  It is commonly used in older AMD chips.  It is
  only called JEDEC because the JEDEC association
  <http://www.jedec.org/> distributes the identification codes for the
  chips. WARNING!!!! This code does not compile and is incomplete as
  are the specific JEDEC devices drivers.

CONFIG_MTD_ABSENT
  This option enables support for a dummy probing driver used to
  allocated placeholder MTD devices on systems that have socketed
  or removable media.  Use of this driver as a fallback chip probe
  preserves the expected registration order of MTD device nodes on
  the system regardless of media presence.  Device nodes created
  with this driver will return -ENODEV upon access.

CONFIG_MTD_JEDECPROBE
  This option enables JEDEC-style probing of flash chips which are not
  compatible with the Common Flash Interface, but will use the common
  CFI-targetted flash drivers for any chips which are identified which
  are in fact compatible in all but the probe method. This actually
  covers most AMD/Fujitsu-compatible chips, and will shortly cover also
  non-CFI Intel chips (that code is in MTD CVS and should shortly be sent
  for inclusion in Linus' tree)

CONFIG_MTD_OBSOLETE_CHIPS
  This option does not enable any code directly, but will allow you to
  select some other chip drivers which are now considered obsolete,
  because the generic CONFIG_JEDEC_PROBE code above should now detect
  the chips which are supported by these drivers, and allow the generic
  CFI-compatible drivers to drive the chips. Say 'N' here unless you have
  already tried the CONFIG_JEDEC_PROBE method and reported its failure
  to the MTD mailing list at <linux-mtd@lists.infradead.org>