[U-Boot] board/freescale/mx6slevk: Add support for SPI NOR on the Freescale MCIMX6SLEVK Board

[Fabio Estevam]

On Thu, Apr 10, 2014 at 12:05 PM, Sam Catch <dsblue.spam at gmail.com> wrote:
> I hope this email is now in the right format.
>
> Hi All,
>
> I am trying to add support for the SPI NOR device on the  Freescale
> MCIMX6SLEVK Board.  I have created a patch that should enable support but
> the u-boot probe command still does not find the device.  The process fails
> during the ECSPI transfer.
>
> I have tried the following patch to the latest git master of u-boot:
>
> http://pastebin.com/hamK7Ybb
>
> U-Boot Output:
>
> => sf probe
> SF: Unsupported flash IDs: manuf 00, jedec 0000, ext_jedec 0000
> Failed to initialize SPI flash at 0:27392
>
> Does anyone have any insight as to why the Probe may be failing?  I modeled
> the changes on the mx6sabresd board.

I see the same error here. I measured with a scope and the chip select
signal behaves very differently compared to the mx6qsabresd board.

When I do 'sf probe' on a mx6qsabresd the chip select line stays low
for 10us and then stays high.

On mx6slevk the chip select line stays low for 0.5us, then it goes
high, goes low for 2us and they stays high.

So there is something very wrong with the timings on mx6sl, but I
haven't had a chance to debug this yet.

Regards,

Fabio Estevam