Merge tag 'ieee802154-for-davem-2021-04-07' of git://git.kernel.org/pub/scm/linux...

[linux-2.6-microblaze.git] / drivers / iommu / tegra-smmu.c

diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c
index 4a3f095..602aab9 100644 (file)
--- a/drivers/iommu/tegra-smmu.c
+++ b/drivers/iommu/tegra-smmu.c
@@ -798,10 +798,69 @@ static phys_addr_t tegra_smmu_iova_to_phys(struct iommu_domain *domain,
        return SMMU_PFN_PHYS(pfn) + SMMU_OFFSET_IN_PAGE(iova);
 }
 
+static struct tegra_smmu *tegra_smmu_find(struct device_node *np)
+{
+       struct platform_device *pdev;
+       struct tegra_mc *mc;
+
+       pdev = of_find_device_by_node(np);
+       if (!pdev)
+               return NULL;
+
+       mc = platform_get_drvdata(pdev);
+       if (!mc)
+               return NULL;
+
+       return mc->smmu;
+}
+
+static int tegra_smmu_configure(struct tegra_smmu *smmu, struct device *dev,
+                               struct of_phandle_args *args)
+{
+       const struct iommu_ops *ops = smmu->iommu.ops;
+       int err;
+
+       err = iommu_fwspec_init(dev, &dev->of_node->fwnode, ops);
+       if (err < 0) {
+               dev_err(dev, "failed to initialize fwspec: %d\n", err);
+               return err;
+       }
+
+       err = ops->of_xlate(dev, args);
+       if (err < 0) {
+               dev_err(dev, "failed to parse SW group ID: %d\n", err);
+               iommu_fwspec_free(dev);
+               return err;
+       }
+
+       return 0;
+}
+
 static struct iommu_device *tegra_smmu_probe_device(struct device *dev)
 {
-       struct tegra_smmu *smmu = dev_iommu_priv_get(dev);
+       struct device_node *np = dev->of_node;
+       struct tegra_smmu *smmu = NULL;
+       struct of_phandle_args args;
+       unsigned int index = 0;
+       int err;
+
+       while (of_parse_phandle_with_args(np, "iommus", "#iommu-cells", index,
+                                         &args) == 0) {
+               smmu = tegra_smmu_find(args.np);
+               if (smmu) {
+                       err = tegra_smmu_configure(smmu, dev, &args);
 
+                       if (err < 0) {
+                               of_node_put(args.np);
+                               return ERR_PTR(err);
+                       }
+               }
+
+               of_node_put(args.np);
+               index++;
+       }
+
+       smmu = dev_iommu_priv_get(dev);
        if (!smmu)
                return ERR_PTR(-ENODEV);
 
@@ -1028,6 +1087,16 @@ struct tegra_smmu *tegra_smmu_probe(struct device *dev,
        if (!smmu)
                return ERR_PTR(-ENOMEM);
 
+       /*
+        * This is a bit of a hack. Ideally we'd want to simply return this
+        * value. However the IOMMU registration process will attempt to add
+        * all devices to the IOMMU when bus_set_iommu() is called. In order
+        * not to rely on global variables to track the IOMMU instance, we
+        * set it here so that it can be looked up from the .probe_device()
+        * callback via the IOMMU device's .drvdata field.
+        */
+       mc->smmu = smmu;
+
        size = BITS_TO_LONGS(soc->num_asids) * sizeof(long);
 
        smmu->asids = devm_kzalloc(dev, size, GFP_KERNEL);