PCI: keystone: Add separate functions for configuring MSI and legacy interrupt

ks_pcie_get_irq_controller_info() is used to configure both MSI and
legacy interrupt. This will prevent MSI or legacy interrupt specific
intializations. Add separate functions to configure MSI and legacy
interrupts.
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

drivers/pci/controller/dwc/pci-keystone.c

@@ -87,11 +87,9 @@ struct keystone_pcie {
 	struct dw_pcie		*pci;
 	/* PCI Device ID */
 	u32			device_id;
-	int			num_legacy_host_irqs;
 	int			legacy_host_irqs[PCI_NUM_INTX];
 	struct			device_node *legacy_intc_np;
 
-	int			num_msi_host_irqs;
 	int			msi_host_irqs[MAX_MSI_HOST_IRQS];
 	int			num_lanes;
 	u32			num_viewport;
@@ -201,14 +199,6 @@ static int ks_pcie_msi_host_init(struct pcie_port *pp)
 	return dw_pcie_allocate_domains(pp);
 }
 
-static void ks_pcie_enable_legacy_irqs(struct keystone_pcie *ks_pcie)
-{
-	int i;
-
-	for (i = 0; i < PCI_NUM_INTX; i++)
-		ks_pcie_app_writel(ks_pcie, IRQ_ENABLE_SET(i), 0x1);
-}
-
 static void ks_pcie_handle_legacy_irq(struct keystone_pcie *ks_pcie,
 				      int offset)
 {
@@ -495,17 +485,6 @@ static int __init ks_pcie_dw_host_init(struct keystone_pcie *ks_pcie)
 
 	ks_pcie->app = *res;
 
-	/* Create legacy IRQ domain */
-	ks_pcie->legacy_irq_domain =
-			irq_domain_add_linear(ks_pcie->legacy_intc_np,
-					      PCI_NUM_INTX,
-					      &ks_pcie_legacy_irq_domain_ops,
-					      NULL);
-	if (!ks_pcie->legacy_irq_domain) {
-		dev_err(dev, "Failed to add irq domain for legacy irqs\n");
-		return -EINVAL;
-	}
-
 	return dw_pcie_host_init(pp);
 }
 
@@ -622,85 +601,109 @@ static void ks_pcie_legacy_irq_handler(struct irq_desc *desc)
 	chained_irq_exit(chip, desc);
 }
 
-static int ks_pcie_get_irq_controller_info(struct keystone_pcie *ks_pcie,
-					   char *controller, int *num_irqs)
+static int ks_pcie_config_msi_irq(struct keystone_pcie *ks_pcie)
 {
-	int temp, max_host_irqs, legacy = 1, *host_irqs;
 	struct device *dev = ks_pcie->pci->dev;
-	struct device_node *np_pcie = dev->of_node, **np_temp;
+	struct device_node *np = ks_pcie->np;
+	struct device_node *intc_np;
+	int irq_count, irq, ret, i;
 
-	if (!strcmp(controller, "msi-interrupt-controller"))
-		legacy = 0;
-
-	if (legacy) {
-		np_temp = &ks_pcie->legacy_intc_np;
-		max_host_irqs = PCI_NUM_INTX;
-		host_irqs = &ks_pcie->legacy_host_irqs[0];
-	} else {
-		np_temp = &ks_pcie->msi_intc_np;
-		max_host_irqs = MAX_MSI_HOST_IRQS;
-		host_irqs =  &ks_pcie->msi_host_irqs[0];
-	}
+	if (!IS_ENABLED(CONFIG_PCI_MSI))
+		return 0;
 
-	/* interrupt controller is in a child node */
-	*np_temp = of_get_child_by_name(np_pcie, controller);
-	if (!(*np_temp)) {
-		dev_err(dev, "Node for %s is absent\n", controller);
+	intc_np = of_get_child_by_name(np, "msi-interrupt-controller");
+	if (!intc_np) {
+		dev_warn(dev, "msi-interrupt-controller node is absent\n");
 		return -EINVAL;
 	}
 
-	temp = of_irq_count(*np_temp);
-	if (!temp) {
-		dev_err(dev, "No IRQ entries in %s\n", controller);
-		of_node_put(*np_temp);
-		return -EINVAL;
+	irq_count = of_irq_count(intc_np);
+	if (!irq_count) {
+		dev_err(dev, "No IRQ entries in msi-interrupt-controller\n");
+		ret = -EINVAL;
+		goto err;
 	}
 
-	if (temp > max_host_irqs)
-		dev_warn(dev, "Too many %s interrupts defined %u\n",
-			(legacy ? "legacy" : "MSI"), temp);
+	if (irq_count > MAX_MSI_HOST_IRQS) {
+		dev_warn(dev, "Too many MSI interrupt lines defined %u\n",
+			 irq_count);
+		irq_count = MAX_MSI_HOST_IRQS;
+	}
 
-	/*
-	 * support upto max_host_irqs. In dt from index 0 to 3 (legacy) or 0 to
-	 * 7 (MSI)
-	 */
-	for (temp = 0; temp < max_host_irqs; temp++) {
-		host_irqs[temp] = irq_of_parse_and_map(*np_temp, temp);
-		if (!host_irqs[temp])
-			break;
+	for (i = 0; i < irq_count; i++) {
+		irq = irq_of_parse_and_map(intc_np, i);
+		if (!irq) {
+			ret = -EINVAL;
+			goto err;
 		}
+		ks_pcie->msi_host_irqs[i] = irq;
 
-	of_node_put(*np_temp);
+		irq_set_chained_handler_and_data(irq, ks_pcie_msi_irq_handler,
+						 ks_pcie);
+	}
 
-	if (temp) {
-		*num_irqs = temp;
+	of_node_put(intc_np);
 	return 0;
-	}
 
-	return -EINVAL;
+err:
+	of_node_put(intc_np);
+	return ret;
 }
 
-static void ks_pcie_setup_interrupts(struct keystone_pcie *ks_pcie)
+static int ks_pcie_config_legacy_irq(struct keystone_pcie *ks_pcie)
 {
-	int i;
+	struct device *dev = ks_pcie->pci->dev;
+	struct irq_domain *legacy_irq_domain;
+	struct device_node *np = ks_pcie->np;
+	struct device_node *intc_np;
+	int irq_count, irq, ret = 0, i;
 
-	/* Legacy IRQ */
-	for (i = 0; i < ks_pcie->num_legacy_host_irqs; i++) {
-		irq_set_chained_handler_and_data(ks_pcie->legacy_host_irqs[i],
-						 ks_pcie_legacy_irq_handler,
-						 ks_pcie);
+	intc_np = of_get_child_by_name(np, "legacy-interrupt-controller");
+	if (!intc_np) {
+		dev_warn(dev, "legacy-interrupt-controller node is absent\n");
+		return -EINVAL;
 	}
-	ks_pcie_enable_legacy_irqs(ks_pcie);
 
-	/* MSI IRQ */
-	if (IS_ENABLED(CONFIG_PCI_MSI)) {
-		for (i = 0; i < ks_pcie->num_msi_host_irqs; i++) {
-			irq_set_chained_handler_and_data(ks_pcie->msi_host_irqs[i],
-							 ks_pcie_msi_irq_handler,
+	irq_count = of_irq_count(intc_np);
+	if (!irq_count) {
+		dev_err(dev, "No IRQ entries in legacy-interrupt-controller\n");
+		ret = -EINVAL;
+		goto err;
+	}
+
+	for (i = 0; i < irq_count; i++) {
+		irq = irq_of_parse_and_map(intc_np, i);
+		if (!irq) {
+			ret = -EINVAL;
+			goto err;
+		}
+		ks_pcie->legacy_host_irqs[i] = irq;
+
+		irq_set_chained_handler_and_data(irq,
+						 ks_pcie_legacy_irq_handler,
 						 ks_pcie);
 	}
+
+	legacy_irq_domain =
+		irq_domain_add_linear(intc_np, PCI_NUM_INTX,
+				      &ks_pcie_legacy_irq_domain_ops, NULL);
+	if (!legacy_irq_domain) {
+		dev_err(dev, "Failed to add irq domain for legacy irqs\n");
+		ret = -EINVAL;
+		goto err;
 	}
+	ks_pcie->legacy_irq_domain = legacy_irq_domain;
+
+	for (i = 0; i < PCI_NUM_INTX; i++)
+		ks_pcie_app_writel(ks_pcie, IRQ_ENABLE_SET(i), INTx_EN);
+
+err:
+	of_node_put(intc_np);
+	return ret;
+}
 
+static void ks_pcie_setup_interrupts(struct keystone_pcie *ks_pcie)
+{
 	if (ks_pcie->error_irq > 0)
 		ks_pcie_enable_error_irq(ks_pcie);
 }
@@ -754,6 +757,14 @@ static int __init ks_pcie_host_init(struct pcie_port *pp)
 	struct keystone_pcie *ks_pcie = to_keystone_pcie(pci);
 	int ret;
 
+	ret = ks_pcie_config_legacy_irq(ks_pcie);
+	if (ret)
+		return ret;
+
+	ret = ks_pcie_config_msi_irq(ks_pcie);
+	if (ret)
+		return ret;
+
 	dw_pcie_setup_rc(pp);
 
 	ks_pcie_establish_link(ks_pcie);
@@ -803,20 +814,6 @@ static int __init ks_pcie_add_pcie_port(struct keystone_pcie *ks_pcie,
 	struct device *dev = &pdev->dev;
 	int ret;
 
-	ret = ks_pcie_get_irq_controller_info(ks_pcie,
-					"legacy-interrupt-controller",
-					&ks_pcie->num_legacy_host_irqs);
-	if (ret)
-		return ret;
-
-	if (IS_ENABLED(CONFIG_PCI_MSI)) {
-		ret = ks_pcie_get_irq_controller_info(ks_pcie,
-						"msi-interrupt-controller",
-						&ks_pcie->num_msi_host_irqs);
-		if (ret)
-			return ret;
-	}
-
 	/*
 	 * Index 0 is the platform interrupt for error interrupt
 	 * from RC.  This is optional.