[U-Boot] [PATCH] mx6qsabrelite: Remove mx6qsabrelite code in favor of nitrogen6x

[Eric Nelson]

Hi Fabio,

On 07/14/2013 09:23 PM, Fabio Estevam wrote:
> Hi Eric,
>
> On Mon, Jul 15, 2013 at 1:09 AM, Eric Nelson
> <eric.nelson at boundarydevices.com> wrote:
>
>>> Agreed :-)
>>>
>>> Reviewed-by: Otavio Salvador <otavio at ossystems.com.br>
>>>
>>
>> +1
>>
>> We should also add something to the README file though.
>
> In this patch I am still using the original README's:
>

Thanks for pointing it out. I had missed this.

> rename board/{freescale/mx6qsabrelite/README =>
> boundary/nitrogen6x/README.mx6qsabrelite} (100%)

I also have to admit not having read this README.

It appears to give pretty bad advice, suggesting that the
user use the iMX6DQ_SPI_to_uSDHC3.bin shim to force
boot from SDHC3.

I think this explains how people keep ending up at that
stale Linaro post.

> rename board/boundary/nitrogen6x/{README => README.nitrogen6x} (100%)
>
> What would you like me to the README?
>

It seems that there are two policy differences between
the mx6qsabrelite.h and nitrogen6x.h files:

1. Use of MMC for environment storage
2. Use of boot script in nitrogen6x

I think we can dispense with #1. Can you think of any reason
a user would care where this is stored?

The second is a bit more subtle. The boot script approach
allows booting any O/S from any FAT or ext2/3/4 from any
SD card or SATA).

OTOH, if there are a significant number of people who don't
have boot scripts in their image(s), we'll give them a
minor speed bump during the transition.

Since these are all environment settings, it seems easy
enough to allow things to be configured in "the Freescale way"
by adding a layer of in-direction.

i.e. we could point 'bootcmd' at either 'bootcmd_boundary'
or 'bootcmd_freescale' and allow a user to select their
flavour of boot.

This would prevent the need for a compile-time switch.

The other difference I note in the default environment
is the inclusion of network boot.

I don't think including this bit does any harm, though
I would suggest that it be a conscious choice and not
an automatic fall-back. In order to enable network
boot, a user already needs to configure at least the
server IP and boot path. Why not also ask them to
set 'bootcmd' to 'bootcmd_net'?

Let me know your thoughts.

Regards,


Eric