[PATCH v4 03/20] iommu/tegra: gart: Ignore devices without IOMMU phandle in DT

Dmitry Osipenko
2018-09-24T00:46:18Z

GART can't handle all devices, hence ignore devices that aren't related
to GART. IOMMU phandle must be explicitly assign to devices in the device
tree.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
---
drivers/iommu/tegra-gart.c | 14 +++++++++++++-
1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/tegra-gart.c b/drivers/iommu/tegra-gart.c
index e9524ed264cf..f6cf5cd5aaca 100644
--- a/drivers/iommu/tegra-gart.c
+++ b/drivers/iommu/tegra-gart.c
@@ -342,8 +342,12 @@ static bool gart_iommu_capable(enum iommu_cap cap)

static int gart_iommu_add_device(struct device *dev)
{
- struct iommu_group *group = iommu_group_get_for_dev(dev);
+ struct iommu_group *group;

+ if (!dev->iommu_fwspec)
+ return -ENODEV;
+
+ group = iommu_group_get_for_dev(dev);
if (IS_ERR(group))
return PTR_ERR(group);

@@ -360,6 +364,12 @@ static void gart_iommu_remove_device(struct device *dev)
iommu_device_unlink(&gart_handle->iommu, dev);
}

+static int gart_iommu_of_xlate(struct device *dev,
+ struct of_phandle_args *args)
+{
+ return 0;
+}
+
static const struct iommu_ops gart_iommu_ops = {
.capable = gart_iommu_capable,
.domain_alloc = gart_iommu_domain_alloc,
@@ -373,6 +383,7 @@ static const struct iommu_ops gart_iommu_ops = {
.unmap = gart_iommu_unmap,
.iova_to_phys = gart_iommu_iova_to_phys,
.pgsize_bitmap = GART_IOMMU_PGSIZES,
+ .of_xlate = gart_iommu_of_xlate,
};

static int tegra_gart_suspend(struct device *dev)
@@ -438,6 +449,7 @@ static int tegra_gart_probe(struct platform_device *pdev)
}

iommu_device_set_ops(&gart->iommu, &gart_iommu_ops);
+ iommu_device_set_fwnode(&gart->iommu, dev->fwnode);

ret = iommu_device_register(&gart->iommu);
if (ret) {
--
2.19.0