[U-Boot] [PATCH v2 13/13] mxc nand: Add support for i.MX5

[Benoît Thébaudeau]

Hi Scott,

On Saturday, November 17, 2012 1:01:03 AM, Scott Wood wrote:
> On 11/16/2012 02:28:16 PM, Benoît Thébaudeau wrote:
> > Also, I've noticed that some of the oobfree fields of the
> > nand_ecclayout
> > structures in mxc_nand.c are slightly different from what can be
> > found in Linux.
> > Any idea about which one is correct (if any)?
> 
> Unless there's an obvious error such as overlap with ECC or a bad
> block
> marker, there isn't really a right answer (except to the extent that
> you're wasting bytes) -- but it's important that everyone agree.  So
> the answer is basically, "which compatibility would it hurt more to
> break?"
> 
> That said, the U-Boot ones make more sense to me in terms of not
> having
> strange missing bytes.

I've just found this commit, which explains what's going on:
http://git.kernel.org/?p=linux/kernel/git/next/linux-next.git;a=commitdiff;h=8c1fd89a85f898384df02217c09c98c2f39b4832

It looks like Linux is correct here because each structure is used for both 8-
and 16-bit NFs, which seem to have different locations for bad block markers.

This fix is also missing from U-Boot:
http://git.kernel.org/?p=linux/kernel/git/next/linux-next.git;a=commitdiff;h=6c49939869c20550512386610ece45aceb65e7f4
It would help to drop some of the pagesize_2k that are weirdly mixed with
writesize.

Best regards,
Benoît