Re: [PATCH] drm/msm: drop cache sync hack

[Rob Clark]

On Mon, Aug 24, 2020 at 11:52 PM Christoph Hellwig <hch@xxxxxxxxxxxxx> wrote:
>
> On Sat, Aug 22, 2020 at 10:52:54AM -0700, Rob Clark wrote:
> > From: Rob Clark <robdclark@xxxxxxxxxxxx>
> >
> > Now that it isn't causing problems to use dma_map/unmap, we can drop the
> > hack of using dma_sync in certain cases.
>
> Great to see!  What did solve the problems?

should be 0e764a01015dfebff8a8ffd297d74663772e248a ("iommu/arm-smmu:
Allow client devices to select direct mapping")

I still need to confirm whether qcom_iommu needs a similar thing, but
I think it is ok as the iommu phandle link is down one level on the
'mdp' device, rather than attached to the toplevel drm device.

BR,
-R