PCI: Add R-Car Gen2 internal PCI support

This adds internal PCI controller driver for R-Car Gen2 SoC.  There are
three PCI controllers available with only a single EHCI/OHCI device
built-in on each PCI bus.  This gives us three USB channels.  Channel 0 is
shared with the USBHS device, while channel 2 is shared with the USBSS.

The PCI controllers do not support I/O port space mapping, and it is not
needed here.

Signed-off-by: Valentine Barshak <valentine.barshak@cogentembedded.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
diff --git a/drivers/pci/host/Kconfig b/drivers/pci/host/Kconfig
index 3d95048..2e33c2b 100644
--- a/drivers/pci/host/Kconfig
+++ b/drivers/pci/host/Kconfig
@@ -19,4 +19,12 @@
 	bool "NVIDIA Tegra PCIe controller"
 	depends on ARCH_TEGRA
 
+config PCI_RCAR_GEN2
+	bool "Renesas R-Car Gen2 Internal PCI controller"
+	depends on ARM && (ARCH_R8A7790 || ARCH_R8A7791 || COMPILE_TEST)
+	help
+	  Say Y here if you want internal PCI support on R-Car Gen2 SoC.
+	  There are 3 internal PCI controllers available with a single
+	  built-in EHCI/OHCI host controller present on each one.
+
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