[U-Boot] U-boot doubts

[Wolfgang Denk <wd@denx.de>]

Dear Chandra Sekar,

In message <67b11d980912162018j3febe826l91c6b52134123d37@mail.gmail.com> you wrote:
>
>   why do we have two files(env_nand.c and env_flash.c) to manipulate
> environmental variables?

Because NAND flahrequires diofferent handling than NOR flash.

Note there is also common/env_dataflash.c, common/env_eeprom.c,
common/env_mgdisk.c, common/env_nowhere.c, common/env_nvram.c,
common/env_onenand.c, and common/env_sf.c

>   According to my knowledge nand is also a flash type then why we have
> separate file called env_flash.c or is this file will be used for nor flash?

NOR flash is a memory device which is byte-addressable by the
processor. NAND flash is no memory, but a storage device instead,
which needs to be read in buffers into RAM before you can access
arbitrary bytes of it's content.

Best regards,

Wolfgang Denk

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