diff options
| author | Nicolin Chen <nicolinc@nvidia.com> | 2026-03-12 17:36:35 -0700 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2026-03-24 14:04:35 +0000 |
| commit | 9dcef98dbee35b8ae784df04c041efffdd42a69c (patch) | |
| tree | 5c2318a972c8be79fa55d5ca6f6e1eafb5aed09f | |
| parent | 803e41f36d227022ab9bbe780c82283fd4713b2e (diff) | |
iommu/tegra241-cmdqv: Update uAPI to clarify HYP_OWN requirement
>From hardware implementation perspective, a guest tegra241-cmdqv hardware
is different than the host hardware:
- Host HW is backed by a VINTF (HYP_OWN=1)
- Guest HW is backed by a VINTF (HYP_OWN=0)
The kernel driver has an implementation requirement of the HYP_OWN bit in
the VM. So, VMM must follow that to allow the same copy of Linux to work.
Add this requirement to the uAPI, which is currently missing.
Fixes: 4dc0d12474f9 ("iommu/tegra241-cmdqv: Add user-space use support")
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Will Deacon <will@kernel.org>
| -rw-r--r-- | include/uapi/linux/iommufd.h | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h index 1dafbc552d37..f63edbe71d54 100644 --- a/include/uapi/linux/iommufd.h +++ b/include/uapi/linux/iommufd.h @@ -1052,6 +1052,11 @@ struct iommu_fault_alloc { enum iommu_viommu_type { IOMMU_VIOMMU_TYPE_DEFAULT = 0, IOMMU_VIOMMU_TYPE_ARM_SMMUV3 = 1, + /* + * TEGRA241_CMDQV requirements (otherwise, VCMDQs will not work) + * - Kernel will allocate a VINTF (HYP_OWN=0) to back this VIOMMU. So, + * VMM must wire the HYP_OWN bit to 0 in guest VINTF_CONFIG register + */ IOMMU_VIOMMU_TYPE_TEGRA241_CMDQV = 2, }; |