Re: [PATCH 5.3 076/148] mmc: sdhci-of-esdhc: set DMA snooping based on DMA coherence

From: Greg Kroah-Hartman
Date: Thu Oct 10 2019 - 05:10:44 EST

On Thu, Oct 10, 2019 at 09:49:12AM +0100, Russell King - ARM Linux admin wrote:
> Hi Greg,
> On 5th October, Christian Zigotzky <chzigotzky@xxxxxxxxxxx> reported a
> problem with this on PowerPC (at a guess, it looks like there's a
> PowerPC user of this where the DT does not mark the device as
> dma-coherent, but the hardware requires it to be DMA coherent.)
> However, despite sending a reply to him within minutes of his email
> arriving, I've heard nothing since, so there's been no progress on
> working out what is really going on.
> Given that the reporter hasn't responded to my reply, I'm not sure
> what we should be doing with this... maybe the reporter has solved
> his problem, maybe he was using an incorrect DT, we just don't know.

Let's just leave this in, and if this did cause a problem, whatever fix
is made will be sent to Linus and we can then take that fix into stable
as well.


greg k-h