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+NVIDIA Tegra PCIe controller
+
+Required properties:
+- compatible: "nvidia,tegra20-pcie"
+- device_type: Must be "pci"
+- reg: A list of physical base address and length for each set of controller
+ registers. Must contain an entry for each entry in the reg-names property.
+- reg-names: Must include the following entries:
+ "pads": PADS registers
+ "afi": AFI registers
+ "cs": configuration space region
+- interrupts: A list of interrupt outputs of the controller. Must contain an
+ entry for each entry in the interrupt-names property.
+- interrupt-names: Must include the following entries:
+ "intr": The Tegra interrupt that is asserted for controller interrupts
+ "msi": The Tegra interrupt that is asserted when an MSI is received
+- pex-clk-supply: Supply voltage for internal reference clock
+- vdd-supply: Power supply for controller (1.05V)
+- bus-range: Range of bus numbers associated with this controller
+- #address-cells: Address representation for root ports (must be 3)
+ - cell 0 specifies the bus and device numbers of the root port:
+ [23:16]: bus number
+ [15:11]: device number
+ - cell 1 denotes the upper 32 address bits and should be 0
+ - cell 2 contains the lower 32 address bits and is used to translate to the
+ CPU address space
+- #size-cells: Size representation for root ports (must be 2)
+- ranges: Describes the translation of addresses for root ports and standard
+ PCI regions. The entries must be 6 cells each, where the first three cells
+ correspond to the address as described for the #address-cells property
+ above, the fourth cell is the physical CPU address to translate to and the
+ fifth and six cells are as described for the #size-cells property above.
+ - The first two entries are expected to translate the addresses for the root
+ port registers, which are referenced by the assigned-addresses property of
+ the root port nodes (see below).
+ - The remaining entries setup the mapping for the standard I/O, memory and
+ prefetchable PCI regions. The first cell determines the type of region
+ that is setup:
+ - 0x81000000: I/O memory region
+ - 0x82000000: non-prefetchable memory region
+ - 0xc2000000: prefetchable memory region
+ Please refer to the standard PCI bus binding document for a more detailed
+ explanation.
+- clocks: List of clock inputs of the controller. Must contain an entry for
+ each entry in the clock-names property.
+- clock-names: Must include the following entries:
+ "pex": The Tegra clock of that name
+ "afi": The Tegra clock of that name
+ "pcie_xclk": The Tegra clock of that name
+ "pll_e": The Tegra clock of that name
+
+Root ports are defined as subnodes of the PCIe controller node.
+
+Required properties:
+- device_type: Must be "pci"
+- assigned-addresses: Address and size of the port configuration registers
+- reg: PCI bus address of the root port
+- #address-cells: Must be 3
+- #size-cells: Must be 2
+- ranges: Sub-ranges distributed from the PCIe controller node. An empty
+ property is sufficient.
+- nvidia,num-lanes: Number of lanes to use for this port. Valid combinations
+ are:
+ - Root port 0 uses 4 lanes, root port 1 is unused.
+ - Both root ports use 2 lanes.
+
+Example:
+
+SoC DTSI:
+
+ pcie-controller {
+ compatible = "nvidia,tegra20-pcie";
+ device_type = "pci";
+ reg = <0x80003000 0x00000800 /* PADS registers */
+ 0x80003800 0x00000200 /* AFI registers */
+ 0x90000000 0x10000000>; /* configuration space */
+ reg-names = "pads", "afi", "cs";
+ interrupts = <0 98 0x04 /* controller interrupt */
+ 0 99 0x04>; /* MSI interrupt */
+ interrupt-names = "intr", "msi";
+
+ bus-range = <0x00 0xff>;
+ #address-cells = <3>;
+ #size-cells = <2>;
+
+ ranges = <0x82000000 0 0x80000000 0x80000000 0 0x00001000 /* port 0 registers */
+ 0x82000000 0 0x80001000 0x80001000 0 0x00001000 /* port 1 registers */
+ 0x81000000 0 0 0x82000000 0 0x00010000 /* downstream I/O */
+ 0x82000000 0 0xa0000000 0xa0000000 0 0x10000000 /* non-prefetchable memory */
+ 0xc2000000 0 0xb0000000 0xb0000000 0 0x10000000>; /* prefetchable memory */
+
+ clocks = <&tegra_car 70>, <&tegra_car 72>, <&tegra_car 74>,
+ <&tegra_car 118>;
+ clock-names = "pex", "afi", "pcie_xclk", "pll_e";
+ status = "disabled";
+
+ pci@1,0 {
+ device_type = "pci";
+ assigned-addresses = <0x82000800 0 0x80000000 0 0x1000>;
+ reg = <0x000800 0 0 0 0>;
+ status = "disabled";
+
+ #address-cells = <3>;
+ #size-cells = <2>;
+
+ ranges;
+
+ nvidia,num-lanes = <2>;
+ };
+
+ pci@2,0 {
+ device_type = "pci";
+ assigned-addresses = <0x82001000 0 0x80001000 0 0x1000>;
+ reg = <0x001000 0 0 0 0>;
+ status = "disabled";
+
+ #address-cells = <3>;
+ #size-cells = <2>;
+
+ ranges;
+
+ nvidia,num-lanes = <2>;
+ };
+ };
+
+
+Board DTS:
+
+ pcie-controller {
+ status = "okay";
+
+ vdd-supply = <&pci_vdd_reg>;
+ pex-clk-supply = <&pci_clk_reg>;
+
+ /* root port 00:01.0 */
+ pci@1,0 {
+ status = "okay";
+
+ /* bridge 01:00.0 (optional) */
+ pci@0,0 {
+ reg = <0x010000 0 0 0 0>;
+
+ #address-cells = <3>;
+ #size-cells = <2>;
+
+ device_type = "pci";
+
+ /* endpoint 02:00.0 */
+ pci@0,0 {
+ reg = <0x020000 0 0 0 0>;
+ };
+ };
+ };
+ };
+
+Note that devices on the PCI bus are dynamically discovered using PCI's bus
+enumeration and therefore don't need corresponding device nodes in DT. However
+if a device on the PCI bus provides a non-probeable bus such as I2C or SPI,
+device nodes need to be added in order to allow the bus' children to be
+instantiated at the proper location in the operating system's device tree (as
+illustrated by the optional nodes in the example above).