[U-Boot] [PATCH V2] add README.distro file

[Ian Campbell]

On Mon, 2014-12-22 at 13:46 -0700, Stephen Warren wrote:
> From: Dennis Gilmore <dennis at ausil.us>
> 
> Add documentation on how to setup a system to use the generic distro
> configs and boot commands. This spells out what is needed to make a
> system conformant, but does not limit the board to only the defaults.
> 
> Signed-off-by: Dennis Gilmore <dennis at ausil.us>
> [swarren, added concept, user config, BOOT_TARGET_DEVICES sections.
> edited the rest]
> Signed-off-by: Stephen Warren <swarren at nvidia.com>

Looks good thanks. A few comments below.

> +Finally, a few options that are mostly relevant only when using U-Boot-
> +specific boot.scr boot configuration files are enabled This enables
> +compatibility with various board configurations that existed before these
> +distro default existed, and assumed boot.scr-based booting.

Missing a "." in "are enabled This enables", I think.

> +boot_scripts:
> +
> +  The name of U-Boot style boot.scr files that $bootcmd searches for.
> +
> +  Example: boot.scr.uimg boot.scr
> +
> +  (Typically we expect extlinux.conf to be used, but execution of boot.scr is
> +  maintained for backwards-compatibility.)

I'm slightly concerned by the implied deprecation of the boot.scr method
here, since at least Debian uses boot.scr exclusively and not the
extlinux stuff. Will boot.scr be maintained going forward or are there
plans to eventually remove it? I hope it will remain, in which case I'd
be happier if this parenthetical were remove or replaced with something
like "(not used in extlinux.conf mode)".

> +scan_dev_for_extlinux:
> +
> +  If you want to disable extlinux.conf on any disk, delete this.
> +
> +scan_dev_for_scripts:
> +
> +  If you want to disable boot.scr on any disk, delete this.

Does deleting them not result in a message about an undefined command
during boot? Would it be better to replace with some sort of null
command (e.g. ":" in shell, not sure what the u-boto equivalent is).

Ian.