PCI: xilinx: Remove dependency on ARM-specific struct hw_pci

The Xilinx PCIe host controller driver uses pci_common_init_dev(), which
is ARM-specific and requires the ARM struct hw_pci.  The part of
pci_common_init_dev() that is needed is limited and can be done here
without using hw_pci.

Create and scan the root bus directly without using the ARM
pci_common_init_dev() interface.

[bhelgaas: revise changelog to show similarity to 79953dd22c1d ("PCI: rcar: Remove dependency on ARM-specific struct hw_pci")]
Signed-off-by: Bharat Kumar Gogada <bharatku@xilinx.com>
Signed-off-by: Ravi Kiran Gummaluri <rgummal@xilinx.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Michal Simek <michal.simek@xilinx.com>

drivers/pci/host/pcie-xilinx.c

@@ -111,17 +111,11 @@ struct xilinx_pcie_port {
 	u8 root_busno;
 	struct device *dev;
 	struct irq_domain *irq_domain;
-	struct resource bus_range;
 	struct list_head resources;
 };
 
 static DECLARE_BITMAP(msi_irq_in_use, XILINX_NUM_MSI_IRQS);
 
-static inline struct xilinx_pcie_port *sys_to_pcie(struct pci_sys_data *sys)
-{
-	return sys->private_data;
-}
-
 static inline u32 pcie_read(struct xilinx_pcie_port *port, u32 reg)
 {
 	return readl(port->reg_base + reg);
@@ -163,7 +157,7 @@ static void xilinx_pcie_clear_err_interrupts(struct xilinx_pcie_port *port)
  */
 static bool xilinx_pcie_valid_device(struct pci_bus *bus, unsigned int devfn)
 {
-	struct xilinx_pcie_port *port = sys_to_pcie(bus->sysdata);
+	struct xilinx_pcie_port *port = bus->sysdata;
 
 	/* Check if link is up when trying to access downstream ports */
 	if (bus->number != port->root_busno)
@@ -196,7 +190,7 @@ static bool xilinx_pcie_valid_device(struct pci_bus *bus, unsigned int devfn)
 static void __iomem *xilinx_pcie_map_bus(struct pci_bus *bus,
 					 unsigned int devfn, int where)
 {
-	struct xilinx_pcie_port *port = sys_to_pcie(bus->sysdata);
+	struct xilinx_pcie_port *port = bus->sysdata;
 	int relbus;
 
 	if (!xilinx_pcie_valid_device(bus, devfn))
@@ -228,7 +222,7 @@ static void xilinx_pcie_destroy_msi(unsigned int irq)
 
 	if (!test_bit(irq, msi_irq_in_use)) {
 		msi = irq_get_msi_desc(irq);
-		port = sys_to_pcie(msi_desc_to_pci_sysdata(msi));
+		port = msi_desc_to_pci_sysdata(msi);
 		dev_err(port->dev, "Trying to free unused MSI#%d\n", irq);
 	} else {
 		clear_bit(irq, msi_irq_in_use);
@@ -277,7 +271,7 @@ static int xilinx_pcie_msi_setup_irq(struct msi_controller *chip,
 				     struct pci_dev *pdev,
 				     struct msi_desc *desc)
 {
-	struct xilinx_pcie_port *port = sys_to_pcie(pdev->bus->sysdata);
+	struct xilinx_pcie_port *port = pdev->bus->sysdata;
 	unsigned int irq;
 	int hwirq;
 	struct msi_msg msg;
@@ -613,47 +607,6 @@ static void xilinx_pcie_init_port(struct xilinx_pcie_port *port)
 		   XILINX_PCIE_REG_RPSC);
 }
 
-/**
- * xilinx_pcie_setup - Setup memory resources
- * @nr: Bus number
- * @sys: Per controller structure
- *
- * Return: '1' on success and error value on failure
- */
-static int xilinx_pcie_setup(int nr, struct pci_sys_data *sys)
-{
-	struct xilinx_pcie_port *port = sys_to_pcie(sys);
-
-	list_splice_init(&port->resources, &sys->resources);
-
-	return 1;
-}
-
-/**
- * xilinx_pcie_scan_bus - Scan PCIe bus for devices
- * @nr: Bus number
- * @sys: Per controller structure
- *
- * Return: Valid Bus pointer on success and NULL on failure
- */
-static struct pci_bus *xilinx_pcie_scan_bus(int nr, struct pci_sys_data *sys)
-{
-	struct xilinx_pcie_port *port = sys_to_pcie(sys);
-	struct pci_bus *bus;
-
-	port->root_busno = sys->busnr;
-
-	if (IS_ENABLED(CONFIG_PCI_MSI))
-		bus = pci_scan_root_bus_msi(port->dev, sys->busnr,
-					    &xilinx_pcie_ops, sys,
-					    &sys->resources,
-					    &xilinx_pcie_msi_chip);
-	else
-		bus = pci_scan_root_bus(port->dev, sys->busnr,
-					&xilinx_pcie_ops, sys, &sys->resources);
-	return bus;
-}
-
 /**
  * xilinx_pcie_parse_dt - Parse Device tree
  * @port: PCIe port information
@@ -705,8 +658,9 @@ static int xilinx_pcie_parse_dt(struct xilinx_pcie_port *port)
 static int xilinx_pcie_probe(struct platform_device *pdev)
 {
 	struct xilinx_pcie_port *port;
-	struct hw_pci hw;
 	struct device *dev = &pdev->dev;
+	struct pci_bus *bus;
+
 	int err;
 	resource_size_t iobase = 0;
 	LIST_HEAD(res);
@@ -740,24 +694,20 @@ static int xilinx_pcie_probe(struct platform_device *pdev)
 		dev_err(dev, "Getting bridge resources failed\n");
 		return err;
 	}
-
-	platform_set_drvdata(pdev, port);
-
-	/* Register the device */
-	memset(&hw, 0, sizeof(hw));
-	hw = (struct hw_pci) {
-		.nr_controllers	= 1,
-		.private_data	= (void **)&port,
-		.setup		= xilinx_pcie_setup,
-		.map_irq	= of_irq_parse_and_map_pci,
-		.scan		= xilinx_pcie_scan_bus,
-		.ops		= &xilinx_pcie_ops,
-	};
+	bus = pci_create_root_bus(&pdev->dev, 0,
+				  &xilinx_pcie_ops, port, &res);
+	if (!bus)
+		return -ENOMEM;
 
 #ifdef CONFIG_PCI_MSI
 	xilinx_pcie_msi_chip.dev = port->dev;
+	bus->msi = &xilinx_pcie_msi_chip;
 #endif
-	pci_common_init_dev(dev, &hw);
+	pci_scan_child_bus(bus);
+	pci_assign_unassigned_bus_resources(bus);
+	pci_fixup_irqs(pci_common_swizzle, of_irq_parse_and_map_pci);
+	pci_bus_add_devices(bus);
+	platform_set_drvdata(pdev, port);
 
 	return 0;
 }