PCI: hisi: Avoid invalid address space conversions

The sparse checker complains about converting pointers between address
spaces. The pci_config_window.priv pointer is a generic void *, but
hisi_pcie_map_bus() needs a void __iomem *.

This isn't a problem in other drivers because they store the __iomem
pointer in a driver struct. Add a trivial struct hisi_pcie to avoid the
warning.

The sparse warning looks like this:

$ make C=2 drivers/pci/controller/
drivers/pci/controller/dwc/pcie-hisi.c:61:37: warning: incorrect type in initializer (different address spaces)
drivers/pci/controller/dwc/pcie-hisi.c:61:37: expected void [noderef] __iomem *reg_base
drivers/pci/controller/dwc/pcie-hisi.c:61:37: got void *priv

Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Bjorn Helgaas <[e-mail]>
Cc: Zhou Wang <[e-mail]>

drivers/pci/controller/dwc/pcie-hisi.c

···
 
 #if defined(CONFIG_PCI_HISI) || (defined(CONFIG_ACPI) && defined(CONFIG_PCI_QUIRKS))
 
+struct hisi_pcie {
+	void __iomem	*reg_base;
+};
+
 static int hisi_pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
 			     int size, u32 *val)
 {
···
 				       int where)
 {
 	struct pci_config_window *cfg = bus->sysdata;
-	void __iomem *reg_base = cfg->priv;
+	struct hisi_pcie *pcie = cfg->priv;
 
 	if (bus->number == cfg->busr.start)
-		return reg_base + where;
+		return pcie->reg_base + where;
 	else
 		return pci_ecam_map_bus(bus, devfn, where);
 }
···
 static int hisi_pcie_init(struct pci_config_window *cfg)
 {
 	struct device *dev = cfg->parent;
+	struct hisi_pcie *pcie;
 	struct acpi_device *adev = to_acpi_device(dev);
 	struct acpi_pci_root *root = acpi_driver_data(adev);
 	struct resource *res;
-	void __iomem *reg_base;
 	int ret;
+
+	pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL);
+	if (!pcie)
+		return -ENOMEM;
 
 	/*
 	 * Retrieve RC base and size from a HISI0081 device with _UID
···
 		return -ENOMEM;
 	}
 
-	reg_base = devm_pci_remap_cfgspace(dev, res->start, resource_size(res));
-	if (!reg_base)
+	pcie->reg_base = devm_pci_remap_cfgspace(dev, res->start, resource_size(res));
+	if (!pcie->reg_base)
 		return -ENOMEM;
 
-	cfg->priv = reg_base;
+	cfg->priv = pcie;
 	return 0;
 }
 
···
 static int hisi_pcie_platform_init(struct pci_config_window *cfg)
 {
 	struct device *dev = cfg->parent;
+	struct hisi_pcie *pcie;
 	struct platform_device *pdev = to_platform_device(dev);
 	struct resource *res;
-	void __iomem *reg_base;
+
+	pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL);
+	if (!pcie)
+		return -ENOMEM;
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 	if (!res) {
···
 		return -EINVAL;
 	}
 
-	reg_base = devm_pci_remap_cfgspace(dev, res->start, resource_size(res));
-	if (!reg_base)
+	pcie->reg_base = devm_pci_remap_cfgspace(dev, res->start, resource_size(res));
+	if (!pcie->reg_base)
 		return -ENOMEM;
 
-	cfg->priv = reg_base;
+	cfg->priv = pcie;
 	return 0;
 }