[U-Boot] [PATCH 9/9] mx23: Use PIO mode support for MMC

Otavio Salvador
2013-01-23T12:12:52Z

On Wed, Jan 23, 2013 at 9:48 AM, Marek Vasut <marex@denx.de> wrote:
> Dear Stefano Babic,
>
>> On 23/01/2013 12:26, Marek Vasut wrote:
>> >>> Hi Otavio, hi Marek,
>> >>>
>> >>> let me say some words about this discussion. I agree that if there is
>> >>> no support for DMA for MX23, we could add support with PIO mode.
>> >>> However, there should be a very good reason, because as far as I
>> >>> understand, added support for DMA is valid for mxs platform. The
>> >>> solution introduced with this patchset lets also the door open for
>> >>> people that can use MX28 in PIO mode. I think (I have already seen in
>> >>> ML Marek's patchset for it) the way to fix DMA for mx23 and then add
>> >>> support for MMC is the rught way to do.
>> >>
>> >> So you'd like to have this patch ported to Marek's patchset so the
>> >> support for PIO mode is kept available? Instead of enabling it for
>> >> MX23 we can have a config option which allows force PIO mode and
>> >> disable DMA. This is what you want?
>> >
>> > Forcing PIO is nonsense, why would it be of any use?
>>
>> No, I agree with Marek - if DMA is then working also for MX23, we do not
>> need PIO at all.
>
> Stefano, it's now using mixed mode -- PIO for small transfers, DMA for large
> transfers. That is the best pick of both worlds ;-)

That's fine; I just wanted to check if I had understood it right.

No problem; I will update the environments and send a v2 of my
patchset basing on top of Marek's changes.

--
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