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@@ -3412,76 +3412,6 @@ following configurations:
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Builds up envcrc with the target environment so that external utils
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may easily extract it and embed it in final U-Boot images.
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-- CONFIG_ENV_IS_IN_FLASH:
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-
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- Define this if the environment is in flash memory.
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-
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- a) The environment occupies one whole flash sector, which is
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- "embedded" in the text segment with the U-Boot code. This
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- happens usually with "bottom boot sector" or "top boot
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- sector" type flash chips, which have several smaller
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- sectors at the start or the end. For instance, such a
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- layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
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- such a case you would place the environment in one of the
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- 4 kB sectors - with U-Boot code before and after it. With
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- "top boot sector" type flash chips, you would put the
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- environment in one of the last sectors, leaving a gap
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- between U-Boot and the environment.
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-
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- - CONFIG_ENV_OFFSET:
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-
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- Offset of environment data (variable area) to the
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- beginning of flash memory; for instance, with bottom boot
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- type flash chips the second sector can be used: the offset
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- for this sector is given here.
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-
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- CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
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-
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- - CONFIG_ENV_ADDR:
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-
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- This is just another way to specify the start address of
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- the flash sector containing the environment (instead of
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- CONFIG_ENV_OFFSET).
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-
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- - CONFIG_ENV_SECT_SIZE:
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-
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- Size of the sector containing the environment.
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-
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-
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- b) Sometimes flash chips have few, equal sized, BIG sectors.
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- In such a case you don't want to spend a whole sector for
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- the environment.
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-
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- - CONFIG_ENV_SIZE:
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-
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- If you use this in combination with CONFIG_ENV_IS_IN_FLASH
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- and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
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- of this flash sector for the environment. This saves
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- memory for the RAM copy of the environment.
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-
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- It may also save flash memory if you decide to use this
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- when your environment is "embedded" within U-Boot code,
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- since then the remainder of the flash sector could be used
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- for U-Boot code. It should be pointed out that this is
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- STRONGLY DISCOURAGED from a robustness point of view:
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- updating the environment in flash makes it always
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- necessary to erase the WHOLE sector. If something goes
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- wrong before the contents has been restored from a copy in
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- RAM, your target system will be dead.
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-
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- - CONFIG_ENV_ADDR_REDUND
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- CONFIG_ENV_SIZE_REDUND
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-
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- These settings describe a second storage area used to hold
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- a redundant copy of the environment data, so that there is
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- a valid backup copy in case there is a power failure during
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- a "saveenv" operation.
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-
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-BE CAREFUL! Any changes to the flash layout, and some changes to the
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-source code will make it necessary to adapt <board>/u-boot.lds*
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-accordingly!
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-
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-
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- CONFIG_ENV_IS_IN_NVRAM:
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Define this if you have some non-volatile memory device
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