disp: msm: move SMMU devices as separate devices

This change adds smmu devices as separate devices and display
driver waits for these devices to bound before using any smmu
operation. This fixes recent stability issues where devices
were not probed during the dpu hw initialization.

Change-Id: Ib08e87c6c0eae0f7e95bbaa60a37bd469d0ecce0
Signed-off-by: Abhijit Kulkarni <kabhijit@codeaurora.org>

msm/msm_smmu.c

@@ -31,10 +31,12 @@
 
 struct msm_smmu_client {
 	struct device *dev;
+	const char *compat;
 	struct iommu_domain *domain;
 	const struct dma_map_ops *dma_ops;
 	bool domain_attached;
 	bool secure;
+	struct list_head smmu_list;
 };
 
 struct msm_smmu {
@@ -51,6 +53,12 @@ struct msm_smmu_domain {
 #define to_msm_smmu(x) container_of(x, struct msm_smmu, base)
 #define msm_smmu_to_client(smmu) (smmu->client)
 
+/* Serialization lock for smmu_list */
+static DEFINE_MUTEX(smmu_list_lock);
+
+/* List of all smmu devices installed */
+static LIST_HEAD(sde_smmu_list);
+
 static int msm_smmu_attach(struct msm_mmu *mmu, const char * const *names,
 		int cnt)
 {
@@ -335,12 +343,36 @@ static const struct of_device_id msm_smmu_dt_match[] = {
 };
 MODULE_DEVICE_TABLE(of, msm_smmu_dt_match);
 
-static struct device *msm_smmu_device_create(struct device *dev,
+static struct msm_smmu_client *msm_smmu_get_smmu(const char *compat)
+{
+	struct msm_smmu_client *curr = NULL;
+	bool found = false;
+
+	if (!compat) {
+		pr_err("invalid param\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	mutex_lock(&smmu_list_lock);
+	list_for_each_entry(curr, &sde_smmu_list, smmu_list) {
+		if (of_compat_cmp(compat, curr->compat, strlen(compat)) == 0) {
+			DRM_DEBUG("found msm_smmu_client for %s\n", compat);
+			found = true;
+			break;
+		}
+	}
+	mutex_unlock(&smmu_list_lock);
+
+	if (!found)
+		return ERR_PTR(-ENODEV);
+
+	return curr;
+}
+
+static struct device *msm_smmu_device_add(struct device *dev,
 		enum msm_mmu_domain_type domain,
 		struct msm_smmu *smmu)
 {
-	struct device_node *child;
-	struct platform_device *pdev;
 	int i;
 	const char *compat = NULL;
 
@@ -357,22 +389,14 @@ static struct device *msm_smmu_device_create(struct device *dev,
 	}
 	DRM_DEBUG("found domain %d compat: %s\n", domain, compat);
 
-	child = of_find_compatible_node(dev->of_node, NULL, compat);
-	if (!child) {
-		DRM_DEBUG("unable to find compatible node for %s\n", compat);
+	smmu->client = msm_smmu_get_smmu(compat);
+	if (IS_ERR_OR_NULL(smmu->client)) {
+		DRM_ERROR("unable to find domain %d compat: %s\n", domain,
+				compat);
 		return ERR_PTR(-ENODEV);
 	}
 
-	pdev = of_platform_device_create(child, NULL, dev);
-	if (!pdev) {
-		DRM_ERROR("unable to create smmu platform dev for domain %d\n",
-				domain);
-		return ERR_PTR(-ENODEV);
-	}
-
-	smmu->client = platform_get_drvdata(pdev);
-
-	return &pdev->dev;
+	return smmu->client->dev;
 }
 
 struct msm_mmu *msm_smmu_new(struct device *dev,
@@ -385,8 +409,8 @@ struct msm_mmu *msm_smmu_new(struct device *dev,
 	if (!smmu)
 		return ERR_PTR(-ENOMEM);
 
-	client_dev = msm_smmu_device_create(dev, domain, smmu);
-	if (IS_ERR(client_dev)) {
+	client_dev = msm_smmu_device_add(dev, domain, smmu);
+	if (IS_ERR_OR_NULL(client_dev)) {
 		kfree(smmu);
 		return (void *)client_dev ? : ERR_PTR(-ENODEV);
 	}
@@ -423,6 +447,34 @@ static int msm_smmu_fault_handler(struct iommu_domain *domain,
 	return rc;
 }
 
+/**
+ * msm_smmu_bind - bind smmu device with controlling device
+ * @dev:        Pointer to base of platform device
+ * @master:     Pointer to container of drm device
+ * @data:       Pointer to private data
+ * Returns:     Zero on success
+ */
+static int msm_smmu_bind(struct device *dev, struct device *master, void *data)
+{
+	return 0;
+}
+
+/**
+ * msm_smmu_unbind - unbind msm_smmu from controlling device
+ * @dev:        Pointer to base of platform device
+ * @master:     Pointer to container of drm device
+ * @data:       Pointer to private data
+ */
+static void msm_smmu_unbind(struct device *dev,
+		struct device *master, void *data)
+{
+}
+
+static const struct component_ops msm_smmu_comp_ops = {
+	.bind = msm_smmu_bind,
+	.unbind = msm_smmu_unbind,
+};
+
 /**
  * msm_smmu_probe()
  * @pdev: platform device
@@ -437,6 +489,7 @@ static int msm_smmu_probe(struct platform_device *pdev)
 	const struct of_device_id *match;
 	struct msm_smmu_client *client;
 	const struct msm_smmu_domain *domain;
+	int ret;
 
 	match = of_match_device(msm_smmu_dt_match, &pdev->dev);
 	if (!match || !match->data) {
@@ -462,6 +515,7 @@ static int msm_smmu_probe(struct platform_device *pdev)
 		dev_err(&pdev->dev, "iommu get domain for dev failed\n");
 		return -EINVAL;
 	}
+	client->compat = match->compatible;
 	client->secure = domain->secure;
 	client->domain_attached = true;
 
@@ -479,16 +533,34 @@ static int msm_smmu_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, client);
 
-	return 0;
+	mutex_lock(&smmu_list_lock);
+	list_add(&client->smmu_list, &sde_smmu_list);
+	mutex_unlock(&smmu_list_lock);
+
+	ret = component_add(&pdev->dev, &msm_smmu_comp_ops);
+	if (ret)
+		pr_err("component add failed\n");
+
+	return ret;
 }
 
 static int msm_smmu_remove(struct platform_device *pdev)
 {
 	struct msm_smmu_client *client;
+	struct msm_smmu_client *curr, *next;
 
 	client = platform_get_drvdata(pdev);
 	client->domain_attached = false;
 
+	mutex_lock(&smmu_list_lock);
+	list_for_each_entry_safe(curr, next, &sde_smmu_list, smmu_list) {
+		if (curr == client) {
+			list_del(&client->smmu_list);
+			break;
+		}
+	}
+	mutex_unlock(&smmu_list_lock);
+
 	return 0;
 }