Re: [PATCH v2 0/3] Add support for using external dma in SDHCI
From: Chunyan Zhang
Date: Thu Nov 29 2018 - 01:14:57 EST
Hi Faiz,
Many thanks for testing this.
On Thu, 29 Nov 2018 at 00:59, Rizvi, Mohammad Faiz Abbas
<faiz_abbas@xxxxxx> wrote:
>
> + Mark Brown
>
> Chunyan,
>
> On 11/21/2018 5:17 PM, Faiz Abbas wrote:
> > Hi Chunyan,
> >
> > On 12/11/18 12:56 PM, Chunyan Zhang wrote:
> >> Currently the generic SDHCI code in the Linux kernel supports the SD
> >> standard DMA integrated into the host controller but does not have any
> >> support for external DMA controllers implemented using dmaengine meaning
> >> that custom code is needed for any systems that use a generic DMA
> >> controller with SDHCI which in practice means any SDHCI controller that
> >> doesn't have an integrated DMA controller so we should have this as a
> >> generic feature.
> >>
> >> There are already a number of controller specific drivers that have dmaengine
> >> code, and some could use sdhci.c actually, but needed to implement mmc_ops->request()
> >> in their specific driver for sending command with external dma using dmaengine
> >> framework, with this patchset, them will take advantage of the generic support.
> >> TI's omap controller is the case as an example.
> >>
> >> Any comments are very appreciated.
> >>
> >
> > This is great. It helps us move am335x and am43xx platforms to
> > sdhci-omap. What platforms have you tested this on?
> >
>
> Gentle ping on this. I tried testing these with an am335x-evm board. In
> their current condition, the card fails to enumerate altogether. The
> changes suggested by Adrian should fix this. Let me know when you post a v3.
I addressed Adrian's comments, and posted a new patch under 1/3 of the
last patch series, if this patch can be verified workable, I will send
another new patchset also add your tested-by.
Thanks,
Chunyan
>
> Thanks,
> Faiz