env: Move help from README to Kconfig

The CONFIG_ENV_IS_IN_... options which have already been converted to
Kconfig only have a small amount of help. Move the rest of it over from
the README.

Signed-off-by: Simon Glass <sjg@chromium.org>

1 files changed, 101 insertions, 2 deletions

diff --git a/common/Kconfig b/common/Kconfig
index e06089b810b..de7584f7783 100644
--- a/common/Kconfig
+++ b/common/Kconfig
@@ -184,6 +184,52 @@ config ENV_IS_IN_MMC
 	  Define this if you have an MMC device which you want to use for the
 	  environment.
 
+	  CONFIG_SYS_MMC_ENV_DEV:
+
+	  Specifies which MMC device the environment is stored in.
+
+	  CONFIG_SYS_MMC_ENV_PART (optional):
+
+	  Specifies which MMC partition the environment is stored in. If not
+	  set, defaults to partition 0, the user area. Common values might be
+	  1 (first MMC boot partition), 2 (second MMC boot partition).
+
+	  CONFIG_ENV_OFFSET:
+	  CONFIG_ENV_SIZE:
+
+	  These two #defines specify the offset and size of the environment
+	  area within the specified MMC device.
+
+	  If offset is positive (the usual case), it is treated as relative to
+	  the start of the MMC partition. If offset is negative, it is treated
+	  as relative to the end of the MMC partition. This can be useful if
+	  your board may be fitted with different MMC devices, which have
+	  different sizes for the MMC partitions, and you always want the
+	  environment placed at the very end of the partition, to leave the
+	  maximum possible space before it, to store other data.
+
+	  These two values are in units of bytes, but must be aligned to an
+	  MMC sector boundary.
+
+	  CONFIG_ENV_OFFSET_REDUND (optional):
+
+	  Specifies a second storage area, of CONFIG_ENV_SIZE size, used to
+	  hold a redundant copy of the environment data. This provides a
+	  valid backup copy in case the other copy is corrupted, e.g. due
+	  to a power failure during a "saveenv" operation.
+
+	  This value may also be positive or negative; this is handled in the
+	  same way as CONFIG_ENV_OFFSET.
+
+	  This value is also in units of bytes, but must also be aligned to
+	  an MMC sector boundary.
+
+	  CONFIG_ENV_SIZE_REDUND (optional):
+
+	  This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is
+	  set. If this value is set, it must be set to the same value as
+	  CONFIG_ENV_SIZE.
+
 config ENV_IS_IN_NAND
 	bool "Environment in a NAND device"
 	depends on !CHAIN_OF_TRUST
@@ -191,12 +237,65 @@ config ENV_IS_IN_NAND
 	  Define this if you have a NAND device which you want to use for the
 	  environment.
 
+	  - CONFIG_ENV_OFFSET:
+	  - CONFIG_ENV_SIZE:
+
+	  These two #defines specify the offset and size of the environment
+	  area within the first NAND device.  CONFIG_ENV_OFFSET must be
+	  aligned to an erase block boundary.
+
+	  - CONFIG_ENV_OFFSET_REDUND (optional):
+
+	  This setting describes a second storage area of CONFIG_ENV_SIZE
+	  size used to hold a redundant copy of the environment data, so
+	  that there is a valid backup copy in case there is a power failure
+	  during a "saveenv" operation.	 CONFIG_ENV_OFFSET_REDUND must be
+	  aligned to an erase block boundary.
+
+	  - CONFIG_ENV_RANGE (optional):
+
+	  Specifies the length of the region in which the environment
+	  can be written.  This should be a multiple of the NAND device's
+	  block size.  Specifying a range with more erase blocks than
+	  are needed to hold CONFIG_ENV_SIZE allows bad blocks within
+	  the range to be avoided.
+
+	  - CONFIG_ENV_OFFSET_OOB (optional):
+
+	  Enables support for dynamically retrieving the offset of the
+	  environment from block zero's out-of-band data.  The
+	  "nand env.oob" command can be used to record this offset.
+	  Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
+	  using CONFIG_ENV_OFFSET_OOB.
+
 config ENV_IS_IN_UBI
 	bool "Environment in a UBI volume"
 	depends on !CHAIN_OF_TRUST
 	help
-	  Define this if you have a UBI volume which you want to use for the
-	  environment.
+	  Define this if you have an UBI volume that you want to use for the
+	  environment.  This has the benefit of wear-leveling the environment
+	  accesses, which is important on NAND.
+
+	  - CONFIG_ENV_UBI_PART:
+
+	  Define this to a string that is the mtd partition containing the UBI.
+
+	  - CONFIG_ENV_UBI_VOLUME:
+
+	  Define this to the name of the volume that you want to store the
+	  environment in.
+
+	  - CONFIG_ENV_UBI_VOLUME_REDUND:
+
+	  Define this to the name of another volume to store a second copy of
+	  the environment in.  This will enable redundant environments in UBI.
+	  It is assumed that both volumes are in the same MTD partition.
+
+	  - CONFIG_UBI_SILENCE_MSG
+	  - CONFIG_UBIFS_SILENCE_MSG
+
+	  You will probably want to define these to avoid a really noisy system
+	  when storing the env in UBI.
 
 config ENV_IS_NOWHERE
 	bool "Environment is not stored"