pci: xilinx: Use pci_generic_mmap_{read, write}_config()

Use the new helper function to avoid boilerplate in the driver.

Note that this changes __raw_writel et al. to writel. AFAICT this is
no problem because:

- The Linux driver for the same hardware uses the non-__raw variants as
  well (via pci_generic_config_write()).
- This driver seems to be used only on MIPS so far, where the __raw and
  non-__raw accessors are the same.

Signed-off-by: Tuomas Tynkkynen <tuomas.tynkkynen@iki.fi>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

drivers/pci/pcie_xilinx.c

@@ -41,7 +41,7 @@ static bool pcie_xilinx_link_up(struct xilinx_pcie *pcie)
 
 /**
  * pcie_xilinx_config_address() - Calculate the address of a config access
- * @pcie: Pointer to the PCI controller state
+ * @udev: Pointer to the PCI bus
  * @bdf: Identifies the PCIe device to access
  * @offset: The offset into the device's configuration space
  * @paddress: Pointer to the pointer to write the calculates address to
@@ -55,9 +55,10 @@ static bool pcie_xilinx_link_up(struct xilinx_pcie *pcie)
  *
  * Return: 0 on success, else -ENODEV
  */
-static int pcie_xilinx_config_address(struct xilinx_pcie *pcie, pci_dev_t bdf,
+static int pcie_xilinx_config_address(struct udevice *udev, pci_dev_t bdf,
 				      uint offset, void **paddress)
 {
+	struct xilinx_pcie *pcie = dev_get_priv(udev);
 	unsigned int bus = PCI_BUS(bdf);
 	unsigned int dev = PCI_DEV(bdf);
 	unsigned int func = PCI_FUNC(bdf);
@@ -101,29 +102,8 @@ static int pcie_xilinx_read_config(struct udevice *bus, pci_dev_t bdf,
 				   uint offset, ulong *valuep,
 				   enum pci_size_t size)
 {
-	struct xilinx_pcie *pcie = dev_get_priv(bus);
-	void *address;
-	int err;
-
-	err = pcie_xilinx_config_address(pcie, bdf, offset, &address);
-	if (err < 0) {
-		*valuep = pci_get_ff(size);
-		return 0;
-	}
-
-	switch (size) {
-	case PCI_SIZE_8:
-		*valuep = __raw_readb(address);
-		return 0;
-	case PCI_SIZE_16:
-		*valuep = __raw_readw(address);
-		return 0;
-	case PCI_SIZE_32:
-		*valuep = __raw_readl(address);
-		return 0;
-	default:
-		return -EINVAL;
-	}
+	return pci_generic_mmap_read_config(bus, pcie_xilinx_config_address,
+					    bdf, offset, valuep, size);
 }
 
 /**
@@ -144,27 +124,8 @@ static int pcie_xilinx_write_config(struct udevice *bus, pci_dev_t bdf,
 				    uint offset, ulong value,
 				    enum pci_size_t size)
 {
-	struct xilinx_pcie *pcie = dev_get_priv(bus);
-	void *address;
-	int err;
-
-	err = pcie_xilinx_config_address(pcie, bdf, offset, &address);
-	if (err < 0)
-		return 0;
-
-	switch (size) {
-	case PCI_SIZE_8:
-		__raw_writeb(value, address);
-		return 0;
-	case PCI_SIZE_16:
-		__raw_writew(value, address);
-		return 0;
-	case PCI_SIZE_32:
-		__raw_writel(value, address);
-		return 0;
-	default:
-		return -EINVAL;
-	}
+	return pci_generic_mmap_write_config(bus, pcie_xilinx_config_address,
+					     bdf, offset, value, size);
 }
 
 /**