[PATCH 2/4] media: omap3isp: Handle ARM dma_iommu_mapping

[Sakari Ailus]

Hi Laurent, others,

On Sat, Feb 15, 2025 at 09:43:28PM +0200, Laurent Pinchart wrote:
> CC'ing Sakari.
> 
> Sakari, would you pick this patch ?

Thanks! I wonder what happened -- it wasn't visible in Linuxtv.org
Patchwork but could be found via the message id.

It's in my tree now.

> 
> On Sat, Feb 15, 2025 at 08:57:24AM +0200, Sicelo wrote:
> > On Mon, Oct 28, 2024 at 05:58:36PM +0000, Robin Murphy wrote:
> > > It's no longer practical for the OMAP IOMMU driver to trick
> > > arm_setup_iommu_dma_ops() into ignoring its presence, so let's use the
> > > same tactic as other IOMMU API users on 32-bit ARM and explicitly kick
> > > the arch code's dma_iommu_mapping out of the way to avoid problems.
> > > 
> > > Fixes: 4720287c7bf7 ("iommu: Remove struct iommu_ops *iommu from arch_setup_dma_ops()")
> > > Signed-off-by: Robin Murphy <robin.murphy at arm.com>
> > > ---
> > >  drivers/media/platform/ti/omap3isp/isp.c | 7 +++++++
> > >  1 file changed, 7 insertions(+)
> > > 
> > > diff --git a/drivers/media/platform/ti/omap3isp/isp.c b/drivers/media/platform/ti/omap3isp/isp.c
> > > index 91101ba88ef0..b2210841a320 100644
> > > --- a/drivers/media/platform/ti/omap3isp/isp.c
> > > +++ b/drivers/media/platform/ti/omap3isp/isp.c
> > > @@ -1961,6 +1961,13 @@ static int isp_attach_iommu(struct isp_device *isp)
> > >  	struct dma_iommu_mapping *mapping;
> > >  	int ret;
> > >  
> > > +	/* We always want to replace any default mapping from the arch code */
> > > +	mapping = to_dma_iommu_mapping(isp->dev);
> > > +	if (mapping) {
> > > +		arm_iommu_detach_device(isp->dev);
> > > +		arm_iommu_release_mapping(mapping);
> > > +	}
> > > +
> > >  	/*
> > >  	 * Create the ARM mapping, used by the ARM DMA mapping core to allocate
> > >  	 * VAs. This will allocate a corresponding IOMMU domain.
> > > -- 
> > > 2.39.2.101.g768bb238c484.dirty
> > > 
> > 
> > I have finally found time to test this patch on the Nokia N900 and can
> > confirm it is working fine.
> > 
> > I was wondering - is there a reason that it is not merged yet? I tested
> > on 6.14-rc2, which did not have it, and notice it is also not in
> > linux-next.
> > 
> > If it helps:
> > 
> > Tested-by: Sicelo A. Mhlongo <absicsz at gmail.com>
> 

-- 
Regards,

Sakari Ailus