PCI: keystone: Assume controller is already in RC mode

Keystone PCI hardware supports both RC and EP modes and devcfg register has
bits to boot strap the device to either of these modes.  It seems proper to
add this functionality to the boot loader rather than in the driver as
device will be operating in either mode, not both any time.  Currently the
driver supports only RC mode and hence register configuration in the driver
is not needed and the driver can assume the hardware is in RC mode.

Also update the DT documentation accordingly.

Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>

Documentation/devicetree/bindings/pci/pci-keystone.txt

@@ -13,9 +13,7 @@ Required Properties:-
 
 compatibility: "ti,keystone-pcie"
 reg:	index 1 is the base address and length of DW application registers.
-	index 2 is the base address and length of PCI mode configuration
-	register.
-	index 3 is the base address and length of PCI device ID register.
+	index 2 is the base address and length of PCI device ID register.
 
 pcie_msi_intc : Interrupt controller device node for MSI IRQ chip
 	interrupt-cells: should be set to 1

drivers/pci/host/pci-keystone.c

@@ -35,10 +35,6 @@
 #define MAX_MSI_HOST_IRQS		8
 #define MAX_LEGACY_HOST_IRQS		4
 
-/* RC mode settings masks */
-#define PCIE_RC_MODE		BIT(2)
-#define PCIE_MODE_MASK		(BIT(1) | BIT(2))
-
 /* DEV_STAT_CTRL */
 #define PCIE_CAP_BASE		0x70
 
@@ -355,7 +351,6 @@ static int __init ks_pcie_probe(struct platform_device *pdev)
 	void __iomem *reg_p;
 	struct phy *phy;
 	int ret = 0;
-	u32 val;
 
 	ks_pcie = devm_kzalloc(&pdev->dev, sizeof(*ks_pcie),
 				GFP_KERNEL);
@@ -365,18 +360,6 @@ static int __init ks_pcie_probe(struct platform_device *pdev)
 	}
 	pp = &ks_pcie->pp;
 
-	/* index 2 is the devcfg register for RC mode settings */
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
-	reg_p = devm_ioremap_resource(dev, res);
-	if (IS_ERR(reg_p))
-		return PTR_ERR(reg_p);
-
-	/* enable RC mode in devcfg */
-	val = readl(reg_p);
-	val &= ~PCIE_MODE_MASK;
-	val |= PCIE_RC_MODE;
-	writel(val, reg_p);
-
 	/* initialize SerDes Phy if present */
 	phy = devm_phy_get(dev, "pcie-phy");
 	if (!IS_ERR_OR_NULL(phy)) {
@@ -385,8 +368,8 @@ static int __init ks_pcie_probe(struct platform_device *pdev)
 			return ret;
 	}
 
-	/* index 3 is to read PCI DEVICE_ID */
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 3);
+	/* index 2 is to read PCI DEVICE_ID */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
 	reg_p = devm_ioremap_resource(dev, res);
 	if (IS_ERR(reg_p))
 		return PTR_ERR(reg_p);