TI Keystone PCIe interface

Keystone PCI host Controller is based on the Synopsys DesignWare PCI
hardware version 3.65.  It shares common functions with the PCIe DesignWare
core driver and inherits common properties defined in
Documentation/devicetree/bindings/pci/designware-pcie.txt

Please refer to Documentation/devicetree/bindings/pci/designware-pcie.txt
for the details of DesignWare DT bindings.  Additional properties are
described here as well as properties that are not applicable.

Required Properties:-

compatibility: Should be "ti,keystone-pcie" for RC on Keystone2 SoC
	       Should be "ti,am654-pcie-rc" for RC on AM654x SoC
reg: Three register ranges as listed in the reg-names property
reg-names: "dbics" for the DesignWare PCIe registers, "app" for the
	   TI specific application registers, "config" for the
	   configuration space address

pcie_msi_intc : Interrupt controller device node for MSI IRQ chip
	interrupt-cells: should be set to 1
	interrupts: GIC interrupt lines connected to PCI MSI interrupt lines
	(required if the compatible is "ti,keystone-pcie")
msi-map: As specified in Documentation/devicetree/bindings/pci/pci-msi.txt
	 (required if the compatible is "ti,am654-pcie-rc".

ti,syscon-pcie-id : phandle to the device control module required to set device
		    id and vendor id.
ti,syscon-pcie-mode : phandle to the device control module required to configure
		      PCI in either RC mode or EP mode.

 Example:
	pcie_msi_intc: msi-interrupt-controller {
			interrupt-controller;
			#interrupt-cells = <1>;
			interrupt-parent = <&gic>;
			interrupts = <GIC_SPI 30 IRQ_TYPE_EDGE_RISING>,
					<GIC_SPI 31 IRQ_TYPE_EDGE_RISING>,
					<GIC_SPI 32 IRQ_TYPE_EDGE_RISING>,
					<GIC_SPI 33 IRQ_TYPE_EDGE_RISING>,
					<GIC_SPI 34 IRQ_TYPE_EDGE_RISING>,
					<GIC_SPI 35 IRQ_TYPE_EDGE_RISING>,
					<GIC_SPI 36 IRQ_TYPE_EDGE_RISING>,
					<GIC_SPI 37 IRQ_TYPE_EDGE_RISING>;
	};

pcie_intc: Interrupt controller device node for Legacy IRQ chip
	interrupt-cells: should be set to 1

 Example:
	pcie_intc: legacy-interrupt-controller {
		interrupt-controller;
		#interrupt-cells = <1>;
		interrupt-parent = <&gic>;
		interrupts = <GIC_SPI 26 IRQ_TYPE_EDGE_RISING>,
			<GIC_SPI 27 IRQ_TYPE_EDGE_RISING>,
			<GIC_SPI 28 IRQ_TYPE_EDGE_RISING>,
			<GIC_SPI 29 IRQ_TYPE_EDGE_RISING>;
	};

Optional properties:-
	phys: phandle to generic Keystone SerDes PHY for PCI
	phy-names: name of the generic Keystone SerDes PHY for PCI
	  - If boot loader already does PCI link establishment, then phys and
	    phy-names shouldn't be present.
	interrupts: platform interrupt for error interrupts.

DesignWare DT Properties not applicable for Keystone PCI

1. pcie_bus clock-names not used.  Instead, a phandle to phys is used.

AM654 PCIe Endpoint
===================

Required Properties:-

compatibility: Should be "ti,am654-pcie-ep" for EP on AM654x SoC
reg: Four register ranges as listed in the reg-names property
reg-names: "dbics" for the DesignWare PCIe registers, "app" for the
	   TI specific application registers, "atu" for the
	   Address Translation Unit configuration registers and
	   "addr_space" used to map remote RC address space
num-ib-windows: As specified in
		Documentation/devicetree/bindings/pci/designware-pcie.txt
num-ob-windows: As specified in
		Documentation/devicetree/bindings/pci/designware-pcie.txt
num-lanes: As specified in
	   Documentation/devicetree/bindings/pci/designware-pcie.txt
power-domains: As documented by the generic PM domain bindings in
	       Documentation/devicetree/bindings/power/power_domain.txt.
ti,syscon-pcie-mode: phandle to the device control module required to configure
		      PCI in either RC mode or EP mode.

Optional properties:-

phys: list of PHY specifiers (used by generic PHY framework)
phy-names: must be "pcie-phy0", "pcie-phy1", "pcie-phyN".. based on the
               number of lanes as specified in *num-lanes* property.
("phys" and "phy-names" DT bindings are specified in
Documentation/devicetree/bindings/phy/phy-bindings.txt)
interrupts: platform interrupt for error interrupts.

pcie-ep {
	compatible = "ti,am654-pcie-ep";
	reg =  <0x5500000 0x1000>, <0x5501000 0x1000>,
	       <0x10000000 0x8000000>, <0x5506000 0x1000>;
	reg-names = "app", "dbics", "addr_space", "atu";
	power-domains = <&k3_pds 120>;
	ti,syscon-pcie-mode = <&pcie0_mode>;
	num-lanes = <1>;
	num-ib-windows = <16>;
	num-ob-windows = <16>;
	interrupts = <GIC_SPI 340 IRQ_TYPE_EDGE_RISING>;
};