[U-Boot] [PATCH 0/5] Add support for using an UBI volume for environment

[Scott Wood]

On 02/08/2013 02:07:21 PM, Joe Hershberger wrote:
> NAND is not good at handling absolute addresses to sectors for storing
> particular data.  The current implementation of the NAND env support
> works around this in several ways such as storing a pointer to the
> sector in the OOB of the first sector (interferes with some CRC) or
> supporting a range of sectors (which unless it is huge is not
> guaranteed to be safe).  None of these options address wear-leveling
> concerns or bad block handling.
> 
> Accessing the u-boot env from UBI eliminates these concerns.  However,
> it does require some of the basic settings for finding the UBI env to
> be in the default u-boot env.

The downside is this moves us further away from having an environment  
available before relocation (e.g. loaded by SPL), which is important  
not just for serial config but also hwconfig, which can affect how RAM  
is set up among other things.

Maybe the "OOB of first sector" approach could be changed to be more  
like how bad block tables are allocated, with a special marker in the  
env block's own OOB that we scan for.

-Scott