diff mbox series

[v7,12/24] iommu/tegra-smmu: Support DMA domains in tegra

Message ID 12-v7-de04a3217c48+15055-iommu_all_defdom_jgg@nvidia.com (mailing list archive)
State Superseded
Headers show
Series iommu: Make default_domain's mandatory | expand

Commit Message

Jason Gunthorpe Aug. 23, 2023, 4:47 p.m. UTC 
All ARM64 iommu drivers should support IOMMU_DOMAIN_DMA to enable
dma-iommu.c.

tegra is blocking dma-iommu usage, and also default_domain's, because it
wants an identity translation. This is needed for some device quirk. The
correct way to do this is to support IDENTITY domains and use
ops->def_domain_type() to return IOMMU_DOMAIN_IDENTITY for only the quirky
devices.

Add support for IOMMU_DOMAIN_DMA and force IOMMU_DOMAIN_IDENTITY mode for
everything so no behavior changes.

Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
---
 drivers/iommu/tegra-smmu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Jerry Snitselaar Aug. 28, 2023, 8:27 p.m. UTC | #1 
On Wed, Aug 23, 2023 at 01:47:26PM -0300, Jason Gunthorpe wrote:
> All ARM64 iommu drivers should support IOMMU_DOMAIN_DMA to enable
> dma-iommu.c.
> 
> tegra is blocking dma-iommu usage, and also default_domain's, because it
> wants an identity translation. This is needed for some device quirk. The
> correct way to do this is to support IDENTITY domains and use
> ops->def_domain_type() to return IOMMU_DOMAIN_IDENTITY for only the quirky
> devices.
> 
> Add support for IOMMU_DOMAIN_DMA and force IOMMU_DOMAIN_IDENTITY mode for
> everything so no behavior changes.
> 
> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
> ---
>  drivers/iommu/tegra-smmu.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 

Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
diff mbox series

Patch

diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c
index 80481e1ba561b8..b91ad1b5a20d36 100644
--- a/drivers/iommu/tegra-smmu.c
+++ b/drivers/iommu/tegra-smmu.c
@@ -276,7 +276,7 @@  static struct iommu_domain *tegra_smmu_domain_alloc(unsigned type)
 {
 	struct tegra_smmu_as *as;
 
-	if (type != IOMMU_DOMAIN_UNMANAGED)
+	if (type != IOMMU_DOMAIN_UNMANAGED && type != IOMMU_DOMAIN_DMA)
 		return NULL;
 
 	as = kzalloc(sizeof(*as), GFP_KERNEL);