[U-Boot] [PATCH 1/1] mx51evk: savenv or env save command does not work

[Stefano Babic <sbabic@denx.de>]

On 11/17/2010 02:44 AM, Jason Liu wrote:
> 
>  I set it according to the following reason,
> 
> - Keep the same setting as the original when you commit the mx51
> support patch. Why you select 128KB? :)

No idea, I cannot remember, probably I missed the point. When I commit
the mx51 stuff, there is no possibility to store the environment, so
there are no drawbacks, but I commit some dead code.

> - As I looked through other platform such as OMAP4 for MMC ENV
> setting, it's also set for 128KB

Well, probably the value was copied even in from a flash setup. In case
of flash (NAND or NOR) we must reserved at least 1 sector to store the
environment, and because nowadays flash chips are bigger as in the past
it is very common that the sector size is 128KB or even larger.

However, this does not apply to MMC. A large environment space when we
do not need requires more time to save and to read, last thing has
consequences on the boot time.

> - Leave much room for the user to store customer env.

I do not think there someone needing 128KB to store the environment....

> It's always the trade-off, set to 512B or less will save some time
> according to 128KB, but it will face much risk to change the code
> frequently to meet the increasing env size requirement.
> what's the size do you think is suitable?

I have expected a value such as 8-16KB.

Best regards,
Stefano Babic

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