[PATCH v1 09/20] iommu/mkt_iommu: Implement mtk_iommu_test_device

Nicolin Chen
2025-10-13T00:06:09Z

Move sanity and compatibility tests from the attach_dev callback to the
new test_dev callback function. The IOMMU core makes sure an attach_dev
call must be invoked after a successful test_dev call.

Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
---
drivers/iommu/mtk_iommu.c | 17 +++++++++++++++--
1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index 9747ef1644138..0cfcd0d08ae64 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c
@@ -704,6 +704,20 @@ static void mtk_iommu_domain_free(struct iommu_domain *domain)
kfree(to_mtk_domain(domain));
}

+static int mtk_iommu_test_device(struct iommu_domain *domain,
+ struct device *dev, ioasid_t pasid,
+ struct iommu_domain *old)
+{
+ struct mtk_iommu_data *data = dev_iommu_priv_get(dev);
+ int region_id;
+
+ region_id = mtk_iommu_get_iova_region_id(dev, data->plat_data);
+ if (region_id < 0)
+ return region_id;
+
+ return 0;
+}
+
static int mtk_iommu_attach_device(struct iommu_domain *domain,
struct device *dev, struct iommu_domain *old)
{
@@ -716,8 +730,6 @@ static int mtk_iommu_attach_device(struct iommu_domain *domain,
int ret, region_id;

region_id = mtk_iommu_get_iova_region_id(dev, data->plat_data);
- if (region_id < 0)
- return region_id;

bankid = mtk_iommu_get_bank_id(dev, data->plat_data);
mutex_lock(&dom->mutex);
@@ -1019,6 +1031,7 @@ static const struct iommu_ops mtk_iommu_ops = {
.get_resv_regions = mtk_iommu_get_resv_regions,
.owner = THIS_MODULE,
.default_domain_ops = &(const struct iommu_domain_ops) {
+ .test_dev = mtk_iommu_test_device,
.attach_dev = mtk_iommu_attach_device,
.map_pages = mtk_iommu_map,
.unmap_pages = mtk_iommu_unmap,
--
2.43.0