PCI: xilinx: Keep both legacy and MSI interrupt domain references

When built with MSI support, the legacy domain reference was being
overwritten with MSI.

Create two separate domains for MSI and legacy interrupts.
Signed-off-by: NBharat Kumar Gogada <bharatku@xilinx.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NMichal Simek <michal.simek@xilinx.com>

drivers/pci/host/pcie-xilinx.c

@@ -101,7 +101,8 @@
  * @msi_pages: MSI pages
  * @root_busno: Root Bus number
  * @dev: Device pointer
- * @irq_domain: IRQ domain pointer
+ * @msi_domain: MSI IRQ domain pointer
+ * @leg_domain: Legacy IRQ domain pointer
  * @resources: Bus Resources
  */
 struct xilinx_pcie_port {
@@ -110,7 +111,8 @@ struct xilinx_pcie_port {
 	unsigned long msi_pages;
 	u8 root_busno;
 	struct device *dev;
-	struct irq_domain *irq_domain;
+	struct irq_domain *msi_domain;
+	struct irq_domain *leg_domain;
 	struct list_head resources;
 };
 
@@ -281,7 +283,7 @@ static int xilinx_pcie_msi_setup_irq(struct msi_controller *chip,
 	if (hwirq < 0)
 		return hwirq;
 
-	irq = irq_create_mapping(port->irq_domain, hwirq);
+	irq = irq_create_mapping(port->msi_domain, hwirq);
 	if (!irq)
 		return -EINVAL;
 
@@ -443,7 +445,7 @@ static irqreturn_t xilinx_pcie_intr_handler(int irq, void *data)
 			/* Handle INTx Interrupt */
 			val = ((val & XILINX_PCIE_RPIFR1_INTR_MASK) >>
 				XILINX_PCIE_RPIFR1_INTR_SHIFT) + 1;
-			generic_handle_irq(irq_find_mapping(port->irq_domain,
+			generic_handle_irq(irq_find_mapping(port->leg_domain,
 							    val));
 		}
 	}
@@ -526,12 +528,14 @@ static void xilinx_pcie_free_irq_domain(struct xilinx_pcie_port *port)
 	}
 
 	for (i = 0; i < num_irqs; i++) {
-		irq = irq_find_mapping(port->irq_domain, i);
+		irq = irq_find_mapping(port->leg_domain, i);
 		if (irq > 0)
 			irq_dispose_mapping(irq);
 	}
-
-	irq_domain_remove(port->irq_domain);
+	if (port->leg_domain)
+		irq_domain_remove(port->leg_domain);
+	if (port->msi_domain)
+		irq_domain_remove(port->msi_domain);
 }
 
 /**
@@ -553,21 +557,21 @@ static int xilinx_pcie_init_irq_domain(struct xilinx_pcie_port *port)
 		return -ENODEV;
 	}
 
-	port->irq_domain = irq_domain_add_linear(pcie_intc_node, 4,
+	port->leg_domain = irq_domain_add_linear(pcie_intc_node, 4,
 						 &intx_domain_ops,
 						 port);
-	if (!port->irq_domain) {
+	if (!port->leg_domain) {
 		dev_err(dev, "Failed to get a INTx IRQ domain\n");
 		return -ENODEV;
 	}
 
 	/* Setup MSI */
 	if (IS_ENABLED(CONFIG_PCI_MSI)) {
-		port->irq_domain = irq_domain_add_linear(node,
+		port->msi_domain = irq_domain_add_linear(node,
 							 XILINX_NUM_MSI_IRQS,
 							 &msi_domain_ops,
 							 &xilinx_pcie_msi_chip);
-		if (!port->irq_domain) {
+		if (!port->msi_domain) {
 			dev_err(dev, "Failed to get a MSI IRQ domain\n");
 			return -ENODEV;
 		}