[U-Boot] [PATCH] README: Add new NAND env features

[Scott Wood]

On Fri, 17 Sep 2010 22:47:04 +0200
Wolfgang Denk <wd at denx.de> wrote:

> For example, on NOR flash we might see an erase block size of 256 KiB
> (resulting in a "#define CONFIG_ENV_SECT_SIZE (256 << 10)" or
> similar). But normally we don't need so much space for the
> environment, so we set CONFIG_ENV_SIZE to (for example) 16 KiB. The
> advantage is that with this setting the checksum calculation includes
> only CONFIG_ENV_SIZE, which can be a measurable difference in boot
> time.

The largest NAND page size that I'm aware of is 8 KiB (with 2 or 4 KiB
currently being more common), so it's not as burdensome a restriction --
and NOR flash doesn't have the concept of a NAND-style page; you can
write a word at a time. 

However, I was looking at the master branch when I wrote that.  I
forgot that in my next branch, I have a patch that removes this
requirement (there was existing read-modify-write code, but it was
blocked by an unnecessary check in nand_do_write_ops). :-)

I'll respin the README patch.

-Scott