[U-Boot] Proposal to add NAND-boot support for Sunxi SPL

[Hans de Goede]

Hi Roy,

On 21-05-15 15:59, Roy Spliet wrote:
> The following patches take the work by Daniel Kochmánski, and make some
> heavy modifications for readability and functionality, based on Boris
> Brezillon's Linux driver. Tested on an Olimex Lime w/ A20.
> Patches are sent as RFC. Open questions:
> - Config options added are partially NAND-chip specific. Some options can
> be autodetected based on the NAND ID, others require either brute-forcing
> or config options like these. Do they belong in sunxi-common? Should
> we make a Kconfig option for this? If bikeshedding is desired, are defines
> in sunxi-common.h good enough for now?
> - Style is mostly kernel-like. Satisfied?
> - Daniel: do you think we can work from here?
>
> Please comment away!

Cool stuff. Overall this looks good I'll reply with more detailed feedback
to your individual patches, 2 questions:

1) Can you provide a quick howto (at developer level) on how to actually
get the spl and u-boot into the nand, what I'm looking for is unstructions
like this:

a) Take this git repo + branch, build a kernel from it
b) Look at this dts file for a nand settings example, adjust it for your board
c) Once booted into the kernel using an updated dts you should have these
block devices, dd spl to this one, and u-boot to this one.

No more to go more detailed then that :)

2) What is the plan to add support for loading files from nand in u-boot proper,
so that we can get (e.g.) extlinux.conf + kernel +dtb from a /boot on nand ?

Regards,

Hans