* Switch binding description

The device tree allows to describe the layout of a switch in a system through the "switch" node.


Main node required properties:

- compatible: should be "marvell,mv_switch"
- status: switch status, should be "disabled" or "okay"
- index: switch index, generally it's zero since systeem has only 1 switch generally
- phy_addr: the SMI PHY address to access switch
- gbe_port: the SOC GBE port which switch uplink port is connected to
- cpuPort: the switch port which is connect to SOC CPU
- vid: switch default DB number
- port_mask: switch port mask, if bitn is 1, then the NO. n switch port is valid in physical
- connected_port_mask: which switch ports are being used
- forced_link_port_mask: which switch ports are forced link up
- mtu: switch MTU
- smi_scan_mode: switch SMI scan mode, encoded as follows:
	0 = SMI auto scan mode, scan 0 or 0x10 base address to find the QD
	1 = SMI muanal mode, use QD located at manually defined base addr
	2 = SMI multi address mode, use QD at base addr and use indirect access
- qsgmii_module: 0 or 1, whether there is qsgmii module in switch, 0 is no, 1 is yes
- gephy_on_port: the switch GE PHY ports bitmask
- rgmiia_on_port: the switch RGMII ports bitmask, generally these ports are uplink ports
- switch_irq: if the switch use IRQ mode to report events, then switch_irq is valid and it is
	the switch IRQ number in system; if PHY polling unit is enabled and IRQ is disabled,
	the switch_irq should be 0xffffffff(-1)
- is_speed_2000: if the value is not zero, then the switch CPU port works in 2 Gbps mode
- rgmii_rx_timing_delay: RGMII receive timing control
	0 = default, there is no delay
	1 = add delay to RXCLK for IND inputs when port is in RGMII mode
- rgmii_tx_timing_delay: RGMII transmit timing control
	0 = default, there is no delay
	1 = add delay to GTXCLK for OUTD outputs when port is in RGMII mode

Example:

	In A38x mamba board,  the switch is in external mode, its SMI scan mode is multi address mode,
	and switch SMI address is 2, PHY polling unit is enabled and IRQ is disabled;
	There are 7 ports in the switch, port 5 is connected to GBE port 1 while port 6 is connected
	to the GBE port 0, switch port 6 is the CPU port, switch port 5 and 6 works in RGMII mode
	and should add delay to RXCLK for IND inputs and GTXCLK for OUTD outputs.
	Switch MTU is 1500 and switch does not works in 2G mode;

	switch {
			compatible = "marvell,mv_switch";
			status = "okay";
			index = <0x0>;
			phy_addr = <0x2>;
			gbe_port = <0x0>;
			cpuPort = <0x6>;
			vid = <0>;
			port_mask = <0x7f>;
			connected_port_mask = <0x7f>;
			forced_link_port_mask = <0x60>;
			mtu = <1500>;
			smi_scan_mode = <0x2>;
			qsgmii_module = <0>;
			gephy_on_port = <0x1f>;
			rgmiia_on_port = <0x60>;
			switch_irq = <0xffffffff>;
			is_speed_2000 = <0>;
			rgmii_rx_timing_delay = <1>;
			rgmii_tx_timing_delay = <1>;
		};
