[U-Boot] [RFC PATCH 4/4 v3] mtd: sf: Add CONFIG_SPI_N25Q256A_RESET for software-reset

[Stefan Roese <sr@denx.de>]

On 01.10.2014 21:04, Jagan Teki wrote:
>>>> This is needed for the SoCFPGA booting from SPI NOR flash
>>>> e.g. (N25Q256A). With these changes, the SoCrates can boot and
>>>> re-boot (reset) from SPI NOR flash without any problems.
>>>
>>>
>>> Seems like your SPI NOR reset logic is buggy. Does any of [1] apply to
>>> your
>>> board please?
>>>
>>> [1] http://www.rocketboards.org/foswiki/Documentation/SocBoardQspiBoot
>>
>>
>> Yes. This seems to be that case. But I can't change it right now. So this
>> "solution" with the soft-reset is better than nothing.
>
> If this is some think that must require, any possibility to this
> resetting prior to u-boot?
> like preloader or in first stage boot loader or something.

Perhaps I was not clear with the intention of this patch. Its more to 
show how the problem with SPI flash on this platform / board (SoCrates 
in this case) can be solved. So that others have a reference. Thats why 
I marked it as RFC. Its not really meant for inclusion into mainline.

The real solution is a board rework. If not possible, the preloader 
should be changed. As I don't have access to the preloader code right 
now, this "solution" (I know, its more a hack) didn't seem too bad.

> I feel this is mostly a kind of hardware treat, and looks like it's
> touching generic sf framework
> which is not so good.

Full ack on this. So please don't pull in into mainline.

Thanks,
Stefan