On Fri, Apr 25, 2025 at 10:58:12PM -0700, Nicolin Chen wrote:
Repurpose the @__reserved field in the struct iommu_hw_info_arm_smmuv3, to an HW implementation-defined field @impl.
This will be used by Tegra241 CMDQV implementation on top of a standard ARM SMMUv3 IOMMU. The @impl will be only valid if @flags is set with an implementation-defined flag.
Thus in the driver-level, add an hw_info impl op that will return such a flag to use the impl field.
Signed-off-by: Nicolin Chen nicolinc@nvidia.com
Reviewed-by: Pranjal Shrivastava praan@google.com
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 1 + include/uapi/linux/iommufd.h | 4 ++-- .../iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c | 16 +++++++++++++--- 3 files changed, 16 insertions(+), 5 deletions(-)
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h index a5835af72417..bab7a9ce1283 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h @@ -726,6 +726,7 @@ struct arm_smmu_impl_ops { struct arm_smmu_domain *smmu_domain, struct iommufd_ctx *ictx, unsigned int viommu_type, const struct iommu_user_data *user_data);
- u32 (*hw_info)(struct arm_smmu_device *smmu, u32 *impl);
}; /* An SMMUv3 instance */ diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h index 06a763fda47f..b2614f0f1547 100644 --- a/include/uapi/linux/iommufd.h +++ b/include/uapi/linux/iommufd.h @@ -554,7 +554,7 @@ struct iommu_hw_info_vtd {
(IOMMU_HW_INFO_TYPE_ARM_SMMUV3)- @flags: Must be set to 0
- @__reserved: Must be 0
- @impl: Must be 0
- @idr: Implemented features for ARM SMMU Non-secure programming interface
- @iidr: Information about the implementation and implementer of ARM SMMU,
and architecture version supported@@ -585,7 +585,7 @@ struct iommu_hw_info_vtd { */ struct iommu_hw_info_arm_smmuv3 { __u32 flags;
- __u32 __reserved;
- __u32 impl; __u32 idr[6]; __u32 iidr; __u32 aidr;
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c index a8a78131702d..63861c60b615 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c @@ -10,7 +10,9 @@ void *arm_smmu_hw_info(struct device *dev, u32 *length, u32 *type) { struct arm_smmu_master *master = dev_iommu_priv_get(dev);
- struct arm_smmu_device *smmu = master->smmu; struct iommu_hw_info_arm_smmuv3 *info;
- u32 flags = 0, impl = 0; u32 __iomem *base_idr; unsigned int i;
@@ -18,15 +20,23 @@ void *arm_smmu_hw_info(struct device *dev, u32 *length, u32 *type) if (!info) return ERR_PTR(-ENOMEM);
- base_idr = master->smmu->base + ARM_SMMU_IDR0;
- base_idr = smmu->base + ARM_SMMU_IDR0; for (i = 0; i <= 5; i++) info->idr[i] = readl_relaxed(base_idr + i);
- info->iidr = readl_relaxed(master->smmu->base + ARM_SMMU_IIDR);
- info->aidr = readl_relaxed(master->smmu->base + ARM_SMMU_AIDR);
- info->iidr = readl_relaxed(smmu->base + ARM_SMMU_IIDR);
- info->aidr = readl_relaxed(smmu->base + ARM_SMMU_AIDR);
*length = sizeof(*info); *type = IOMMU_HW_INFO_TYPE_ARM_SMMUV3;
- if (smmu->impl_ops && smmu->impl_ops->hw_info) {
flags = smmu->impl_ops->hw_info(smmu, &impl);if (flags) {info->impl = impl;info->flags |= flags;}- }
- return info;
} -- 2.43.0