[PATCH v2 3/3] iommu/tegra-smmu: Add PCI support

From: Nicolin Chen
Date: Tue Sep 29 2020 - 20:36:00 EST


This patch simply adds support for PCI devices. Also reverses
bus_set_iommu in tegra_smmu_remove().

Signed-off-by: Nicolin Chen <nicoleotsuka@xxxxxxxxx>
---

Changelog
v1->v2
* Added error-out labels in tegra_smmu_probe()
* Dropped pci_request_acs() since IOMMU core would call it.

drivers/iommu/tegra-smmu.c | 33 ++++++++++++++++++++++++---------
1 file changed, 24 insertions(+), 9 deletions(-)

diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c
index cf4981369828..74d84908679e 100644
--- a/drivers/iommu/tegra-smmu.c
+++ b/drivers/iommu/tegra-smmu.c
@@ -10,6 +10,7 @@
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/of_device.h>
+#include <linux/pci.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
@@ -856,6 +857,7 @@ static struct iommu_group *tegra_smmu_device_group(struct device *dev)
const struct tegra_smmu_group_soc *soc;
unsigned int swgroup = fwspec->ids[0];
struct tegra_smmu_group *group;
+ bool pci = dev_is_pci(dev);
struct iommu_group *grp;

/* Find group_soc associating with swgroup */
@@ -882,7 +884,7 @@ static struct iommu_group *tegra_smmu_device_group(struct device *dev)
group->smmu = smmu;
group->soc = soc;

- group->group = iommu_group_alloc();
+ group->group = pci ? pci_device_group(dev) : iommu_group_alloc();
if (IS_ERR(group->group)) {
devm_kfree(smmu->dev, group);
mutex_unlock(&smmu->lock);
@@ -1079,26 +1081,39 @@ struct tegra_smmu *tegra_smmu_probe(struct device *dev,
iommu_device_set_fwnode(&smmu->iommu, dev->fwnode);

err = iommu_device_register(&smmu->iommu);
- if (err) {
- iommu_device_sysfs_remove(&smmu->iommu);
- return ERR_PTR(err);
- }
+ if (err)
+ goto err_sysfs;

err = bus_set_iommu(&platform_bus_type, &tegra_smmu_ops);
- if (err < 0) {
- iommu_device_unregister(&smmu->iommu);
- iommu_device_sysfs_remove(&smmu->iommu);
- return ERR_PTR(err);
+ if (err < 0)
+ goto err_unregister;
+
+#ifdef CONFIG_PCI
+ if (!iommu_present(&pci_bus_type)) {
+ err = bus_set_iommu(&pci_bus_type, &tegra_smmu_ops);
+ if (err < 0)
+ goto err_bus_set;
}
+#endif

if (IS_ENABLED(CONFIG_DEBUG_FS))
tegra_smmu_debugfs_init(smmu);

return smmu;
+
+err_bus_set:
+ bus_set_iommu(&platform_bus_type, NULL);
+err_unregister:
+ iommu_device_unregister(&smmu->iommu);
+err_sysfs:
+ iommu_device_sysfs_remove(&smmu->iommu);
+
+ return ERR_PTR(err);
}

void tegra_smmu_remove(struct tegra_smmu *smmu)
{
+ bus_set_iommu(&platform_bus_type, NULL);
iommu_device_unregister(&smmu->iommu);
iommu_device_sysfs_remove(&smmu->iommu);

--
2.17.1