[U-Boot] [PATCH 2/3] mx6qsabrelite: Change default environment to cope with OE changes

[Otavio Salvador]

On Wed, Sep 19, 2012 at 9:58 PM, Eric Nelson
<eric.nelson at boundarydevices.com> wrote:
> On 09/19/2012 04:51 PM, Otavio Salvador wrote:
>> I sort of agree; do you use 2 or 3 partitions in this case?
>>
>
> Or 1 or 9?
>
> I'm actually not kidding here. The current Freescale Android image
> (R13.4-Beta) actually does want 9 partitions for a bunch of stuff
> like a 'recovery' partition, a 'vendor' partition, etc.
>
> Or even 0? Windows users have been known to use SD cards straight out
> of the box with no partition table.
>
> In short, this is something that can't be solved in the general case,
> so I think it's best for the main-line U-Boot code to not try and
> provide policy, only functionality.

I agree; but mainline could have defaults that works at least for
usual U-Boot hacker. That's why I asked how many you use.

> To that end, we've tried to standardize on something simple: the presence of
> a file named '6q_bootscript' on one of the SD cards that can handle these
> sorts of userspace details:
>
> http://boundarydevices.com/u-boot-conventions-for-i-mx6-nitrogen6x-and-sabrelite/
>
> This allows all of the userspace bits to go into the userspace filesystem,
> but still allows machine-specific like the type of display connected to
> be saved in the environment.
>
> Using this approach, you can load kernel(s) or RAM disks from anywhere
> that U-Boot can reach without re-compiling U-Boot.

This is indeed nice.

>>> Isn't using 'mkenvimage' in OE a better route? That way, the environment
>>> can
>>> change with the userspace decision.
>>
>> In fact in OE we have a patch for it. Usually we don't call mkenvimage
>> for it but I like the idea to add this feature there later.
>
> The best part of doing it in OE is that the same commit should be able to
> update both the environment variables (or boot script) and the parts which depend
> on it (like creation of the filesystem image(s)).

Yes; I will work in a generic way for it in OE ... I like the idea and
also see the added value for the flexibility.

After MX23 I will focus on this ;-) (or Marek kills me :P)

This doesn't solve the question:

Better to have 2 or 3 partition layout by default in mainline?

-- 
Otavio Salvador                             O.S. Systems
E-mail: otavio at ossystems.com.br  http://www.ossystems.com.br
Mobile: +55 53 9981-7854              http://projetos.ossystems.com.br