| Message ID | 20190124180254.20080-5-thierry.reding@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/tegra: Fix IOVA space on Tegra186 and later | expand |
24.01.2019 21:02, Thierry Reding пишет: > From: Thierry Reding <treding@nvidia.com> > > If we use the IOMMU API directly to map buffers into host1x' IOVA space, > we must make sure that the DMA API doesn't already set up a mapping, or > else translation will fail. > > The direct DMA API allows us to allocate memory that will not be mapped > through an IOMMU automatically. > > Signed-off-by: Thierry Reding <treding@nvidia.com> > --- > drivers/gpu/host1x/cdma.c | 11 ++++++++--- > 1 file changed, 8 insertions(+), 3 deletions(-) > > diff --git a/drivers/gpu/host1x/cdma.c b/drivers/gpu/host1x/cdma.c > index 91df51e631b2..ccde23a0109c 100644 > --- a/drivers/gpu/host1x/cdma.c > +++ b/drivers/gpu/host1x/cdma.c > @@ -19,6 +19,7 @@ > > #include <asm/cacheflush.h> > #include <linux/device.h> > +#include <linux/dma-direct.h> > #include <linux/dma-mapping.h> > #include <linux/host1x.h> > #include <linux/interrupt.h> > @@ -70,6 +71,7 @@ static void host1x_pushbuffer_destroy(struct push_buffer *pb) > */ > static int host1x_pushbuffer_init(struct push_buffer *pb) > { > + unsigned long attrs = DMA_ATTR_WRITE_COMBINE; > struct host1x_cdma *cdma = pb_to_cdma(pb); > struct host1x *host1x = cdma_to_host1x(cdma); > struct iova *alloc; > @@ -91,8 +93,8 @@ static int host1x_pushbuffer_init(struct push_buffer *pb) > > size = iova_align(&host1x->iova, size); > > - pb->mapped = dma_alloc_wc(host1x->dev, size, &pb->phys, > - GFP_KERNEL); > + pb->mapped = dma_direct_alloc(host1x->dev, size, &pb->phys, > + GFP_KERNEL, attrs); > if (!pb->mapped) > return -ENOMEM; > > @@ -127,7 +129,10 @@ static int host1x_pushbuffer_init(struct push_buffer *pb) > iommu_free_iova: > __free_iova(&host1x->iova, alloc); > iommu_free_mem: > - dma_free_wc(host1x->dev, size, pb->mapped, pb->phys); > + if (host1x->domain) > + dma_direct_free(host1x->dev, size, pb->mapped, pb->phys, attrs); > + else > + dma_free_wc(host1x->dev, size, pb->mapped, pb->phys); > > return err; > } > This variant looks good for the current upstream code. Alternatively we could check the domain->type==IOMMU_DOMAIN_DMA and skip IOMMU initialization on probe. I may test that nothing breaks with this series for older Tegra's once it all will appear in -next. Please address Mikko's review-comments and push the patches once ready. Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
diff --git a/drivers/gpu/host1x/cdma.c b/drivers/gpu/host1x/cdma.c index 91df51e631b2..ccde23a0109c 100644 --- a/drivers/gpu/host1x/cdma.c +++ b/drivers/gpu/host1x/cdma.c @@ -19,6 +19,7 @@ #include <asm/cacheflush.h> #include <linux/device.h> +#include <linux/dma-direct.h> #include <linux/dma-mapping.h> #include <linux/host1x.h> #include <linux/interrupt.h> @@ -70,6 +71,7 @@ static void host1x_pushbuffer_destroy(struct push_buffer *pb) */ static int host1x_pushbuffer_init(struct push_buffer *pb) { + unsigned long attrs = DMA_ATTR_WRITE_COMBINE; struct host1x_cdma *cdma = pb_to_cdma(pb); struct host1x *host1x = cdma_to_host1x(cdma); struct iova *alloc; @@ -91,8 +93,8 @@ static int host1x_pushbuffer_init(struct push_buffer *pb) size = iova_align(&host1x->iova, size); - pb->mapped = dma_alloc_wc(host1x->dev, size, &pb->phys, - GFP_KERNEL); + pb->mapped = dma_direct_alloc(host1x->dev, size, &pb->phys, + GFP_KERNEL, attrs); if (!pb->mapped) return -ENOMEM; @@ -127,7 +129,10 @@ static int host1x_pushbuffer_init(struct push_buffer *pb) iommu_free_iova: __free_iova(&host1x->iova, alloc); iommu_free_mem: - dma_free_wc(host1x->dev, size, pb->mapped, pb->phys); + if (host1x->domain) + dma_direct_free(host1x->dev, size, pb->mapped, pb->phys, attrs); + else + dma_free_wc(host1x->dev, size, pb->mapped, pb->phys); return err; }