PCI: microchip: Add Microchip PolarFire PCIe controller driver

Add support for the Microchip PolarFire PCIe controller when configured in
host (Root Complex) mode.

[bhelgaas: wrap lines to fit in 80 columns, fix trivial style issues]
Link: https://lore.kernel.org/r/20210125162934.5335-4-daire.mcnamara@microchip.com
Signed-off-by: Daire McNamara <daire.mcnamara@microchip.com>
[lorenzo.pieralisi@arm.com: minor comments tweak]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rob Herring <robh@kernel.org>

drivers/pci/controller/Kconfig

@@ -298,6 +298,16 @@ config PCI_LOONGSON
 	  Say Y here if you want to enable PCI controller support on
 	  Loongson systems.
 
+config PCIE_MICROCHIP_HOST
+	bool "Microchip AXI PCIe host bridge support"
+	depends on PCI_MSI && OF
+	select PCI_MSI_IRQ_DOMAIN
+	select GENERIC_MSI_IRQ_DOMAIN
+	select PCI_HOST_COMMON
+	help
+	  Say Y here if you want kernel to support the Microchip AXI PCIe
+	  Host Bridge driver.
+
 config PCIE_HISI_ERR
 	depends on ACPI_APEI_GHES && (ARM64 || COMPILE_TEST)
 	bool "HiSilicon HIP PCIe controller error handling driver"

drivers/pci/controller/Makefile

@@ -28,6 +28,7 @@ obj-$(CONFIG_PCIE_ROCKCHIP_EP) += pcie-rockchip-ep.o
 obj-$(CONFIG_PCIE_ROCKCHIP_HOST) += pcie-rockchip-host.o
 obj-$(CONFIG_PCIE_MEDIATEK) += pcie-mediatek.o
 obj-$(CONFIG_PCIE_TANGO_SMP8759) += pcie-tango.o
+obj-$(CONFIG_PCIE_MICROCHIP_HOST) += pcie-microchip-host.o
 obj-$(CONFIG_VMD) += vmd.o
 obj-$(CONFIG_PCIE_BRCMSTB) += pcie-brcmstb.o
 obj-$(CONFIG_PCI_LOONGSON) += pci-loongson.o