PCI: dwc: Consolidate devicetree handling in dw_pcie_host_get_resources()

Consolidate devicetree resource handling in dw_pcie_host_get_resources().
No functional change intended.

Link: https://lore.kernel.org/r/20250315201548.858189-5-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>

Author: bjorn-helgaas

drivers/pci/controller/dwc/pcie-designware-host.c

@@ -418,25 +418,15 @@ static void dw_pcie_host_request_msg_tlp_res(struct dw_pcie_rp *pp)
 	}
 }
 
-int dw_pcie_host_init(struct dw_pcie_rp *pp)
+static int dw_pcie_host_get_resources(struct dw_pcie_rp *pp)
 {
 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
 	struct device *dev = pci->dev;
-	struct device_node *np = dev->of_node;
 	struct platform_device *pdev = to_platform_device(dev);
 	struct resource_entry *win;
-	struct pci_host_bridge *bridge;
 	struct resource *res;
 	int ret;
 
-	raw_spin_lock_init(&pp->lock);
-
-	bridge = devm_pci_alloc_host_bridge(dev, 0);
-	if (!bridge)
-		return -ENOMEM;
-
-	pp->bridge = bridge;
-
 	ret = dw_pcie_get_resources(pci);
 	if (ret)
 		return ret;
@@ -455,13 +445,36 @@ int dw_pcie_host_init(struct dw_pcie_rp *pp)
 		return PTR_ERR(pp->va_cfg0_base);
 
 	/* Get the I/O range from DT */
-	win = resource_list_first_type(&bridge->windows, IORESOURCE_IO);
+	win = resource_list_first_type(&pp->bridge->windows, IORESOURCE_IO);
 	if (win) {
 		pp->io_size = resource_size(win->res);
 		pp->io_bus_addr = win->res->start - win->offset;
 		pp->io_base = pci_pio_to_address(win->res->start);
 	}
 
+	return 0;
+}
+
+int dw_pcie_host_init(struct dw_pcie_rp *pp)
+{
+	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
+	struct device *dev = pci->dev;
+	struct device_node *np = dev->of_node;
+	struct pci_host_bridge *bridge;
+	int ret;
+
+	raw_spin_lock_init(&pp->lock);
+
+	bridge = devm_pci_alloc_host_bridge(dev, 0);
+	if (!bridge)
+		return -ENOMEM;
+
+	pp->bridge = bridge;
+
+	ret = dw_pcie_host_get_resources(pp);
+	if (ret)
+		return ret;
+
 	/* Set default bus ops */
 	bridge->ops = &dw_pcie_ops;
 	bridge->child_ops = &dw_child_pcie_ops;