[U-Boot] [PATCH] mxs: Reset the EMI block on mx23

[Otavio Salvador]

On Tue, Jan 29, 2013 at 12:46 AM, Marek Vasut <marex at denx.de> wrote:
> The real reason for memory instability was the fact that the EMI block
> was gated and not reset throughout the boards' operation. This patch
> resets the EMI block properly while also reverts the memory voltage bump.
> The memory stability issues were caused by the EMI not being reset properly
> and thus there is no longer need to run the memory at higher voltage than
> it ought to run at.
>
> This partly reverts 8303ed128a55519f19c5f11087032d4bc4e0537a .
>
> Signed-off-by: Marek Vasut <marex at denx.de>
> Cc: Fabio Estevam <fabio.estevam at freescale.com>
> Cc: Otavio Salvador <otavio at ossystems.com.br>
> Cc: Stefano Babic <sbabic at denx.de>
> ---
>  arch/arm/cpu/arm926ejs/mxs/spl_mem_init.c |   11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)
>
> NOTE: Please apply _SEVERE_ testing!
>

I did a test with and without the patch. *Without* this patch I see an
error in memony but it takes some time to it to error out. With the
patch, the error is mostly instantaneous:

=> mtest
Pattern FFFFFFDD  Writing...  Reading...
Mem error @ 0x40087F6C: found BFFDE002, expected FFFDE002

So it seems to make it worse; but  I am not sure if something else is
missing too.

--
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