[U-Boot] [PATCH 2/5] Enable booting of mx28 without battery

[Graeme Russ <gruss@tss-engineering.com>]

Hi Fabio,

On 22/01/15 23:42, Fabio Estevam wrote:
> Hi Graeme,
>
> On Wed, Jan 21, 2015 at 9:55 AM, Graeme Russ <gruss@tss-engineering.com> wrote:
>> Section 4.1.2 of Freescale Application Note AN4199 describes the
>> configuration required to operate the mx28 from a 5V source without a
>> battery. This patch implements the changes to the Freescale bootlets
>> which allow this configuration to properly boot the mx28 processor
>>
>> Signed-off-by: Graeme Russ <gruss@tss-engineering.com>
>> ---
>>
>>   arch/arm/cpu/arm926ejs/mxs/spl_power_init.c | 190 +++++++++++++++++++++++++++-
>>   doc/README.mxs                              |  10 ++
>
> Damien posted today a new version of this patch in the imx community,
> which is a lot simpler.
>
> Could you please try it?

I've taken a look at it, but decided to leave this patch as-is. Here is 
what I wrote on the Freescale forum:

~~~~
I'm going to keep my U-Boot patch mostly as-is for a few reasons:
- The patch disables battery voltage measurement when there is no battery
- The patch disables all code paths relating to booting from battery
- The power block configuration is based primarily on the Fressscale 
bootlets which I think should be retained unless we can come up with 
some pretty clear and convincing arguments as to why an alternative 
approach is better

I think there is scope for some refactoring of the power block setup 
code in U-Boot, but for now I think it best to leave it as close to the 
bootlet code sequence as practical
~~~~

Regards,


Graeme