Re: [Nouveau] [PATCH v3 2/2] drm/nouveau: tegra: Detach from ARM DMA/IOMMU mapping

2018-05-30 Thread Robin Murphy
On 30/05/18 14:41, Thierry Reding wrote: On Wed, May 30, 2018 at 02:30:51PM +0100, Robin Murphy wrote: On 30/05/18 14:00, Thierry Reding wrote: On Wed, May 30, 2018 at 11:30:25AM +0100, Robin Murphy wrote: On 30/05/18 09:03, Thierry Reding wrote: From: Thierry Reding Depending on the

Re: [Nouveau] [PATCH v3 2/2] drm/nouveau: tegra: Detach from ARM DMA/IOMMU mapping

2018-05-30 Thread Thierry Reding
On Wed, May 30, 2018 at 02:30:51PM +0100, Robin Murphy wrote: > On 30/05/18 14:00, Thierry Reding wrote: > > On Wed, May 30, 2018 at 11:30:25AM +0100, Robin Murphy wrote: > > > On 30/05/18 09:03, Thierry Reding wrote: > > > > From: Thierry Reding > > > > > > > > Depending on the kernel

Re: [Nouveau] [PATCH v3 2/2] drm/nouveau: tegra: Detach from ARM DMA/IOMMU mapping

2018-05-30 Thread Robin Murphy
On 30/05/18 14:00, Thierry Reding wrote: On Wed, May 30, 2018 at 11:30:25AM +0100, Robin Murphy wrote: On 30/05/18 09:03, Thierry Reding wrote: From: Thierry Reding Depending on the kernel configuration, early ARM architecture setup code may have attached the GPU to a DMA/IOMMU mapping that

Re: [Nouveau] [PATCH v3 2/2] drm/nouveau: tegra: Detach from ARM DMA/IOMMU mapping

2018-05-30 Thread Thierry Reding
On Wed, May 30, 2018 at 11:30:25AM +0100, Robin Murphy wrote: > On 30/05/18 09:03, Thierry Reding wrote: > > From: Thierry Reding > > > > Depending on the kernel configuration, early ARM architecture setup code > > may have attached the GPU to a DMA/IOMMU mapping that transparently uses > > the

Re: [Nouveau] [PATCH v3 2/2] drm/nouveau: tegra: Detach from ARM DMA/IOMMU mapping

2018-05-30 Thread Robin Murphy
On 30/05/18 09:03, Thierry Reding wrote: From: Thierry Reding Depending on the kernel configuration, early ARM architecture setup code may have attached the GPU to a DMA/IOMMU mapping that transparently uses the IOMMU to back the DMA API. Tegra requires special handling for IOMMU backed

[Nouveau] [PATCH v3 2/2] drm/nouveau: tegra: Detach from ARM DMA/IOMMU mapping

2018-05-30 Thread Thierry Reding
From: Thierry Reding Depending on the kernel configuration, early ARM architecture setup code may have attached the GPU to a DMA/IOMMU mapping that transparently uses the IOMMU to back the DMA API. Tegra requires special handling for IOMMU backed buffers (a special bit in the GPU's MMU page