Commit 9dcef98d authored by Nicolin Chen's avatar Nicolin Chen Committed by Will Deacon
Browse files

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: 4dc0d124 ("iommu/tegra241-cmdqv: Add user-space use support")
Signed-off-by: default avatarNicolin Chen <nicolinc@nvidia.com>
Reviewed-by: default avatarEric Auger <eric.auger@redhat.com>
Reviewed-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Signed-off-by: default avatarWill Deacon <will@kernel.org>
parent 803e41f3

include/uapi/linux/iommufd.h

+5 −0
Original line number Diff line number Diff line
@@ -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,

};