* Intel XPCS driver

Required properties:
- compatible:	should be "intel,xpcs"
- reg:	address and length of the register set for the device.
- reg-names:	names of the mapped memory regions listed in regs property
- interrupts:	IRQ line info for XPCS, The interrupt specifier
	depends on the interrupt-parent interrupt controller
- interrupt-names:	Name associated with interrupt line
	Should be "xpcs_reset"
- phy: - phys :	the phandle for the PHY device
	(used by generic PHY framework)
- phy-names :	the names of the PHY corresponding to the PHYs present in the
  	 *phy* phandle.
- resets:	Reference to a reset controller asserting the XPCS
- reset-names:	list of reset signal names. Should be "xpcs_reset".
          See: Documentation/devicetree/bindings/reset/reset.txt
-xpcs-mode:	Speed capabilities of the XPCS
	 0 - 10GbE-KR(default)
	 1 - 10GbE-XAUI
	 2 - 1GbE-SGMII
	 3 - 2.5GbE-SGMII
xpcs-cl73:	CL73 configuration
	0 - CL73 ANEG disabled
	1 - CL73 ANEG enabled
xpcs-cl37:	CL37 configuration
	0 - CL37 ANEG disabled
	1 - CL37 ANEG enabled in SGMII MAC Side
	2 - CL37 ANEG enabled in SGMII PHY Side
	3 - CL37 ANEG enabled (BaseX)
xpcs-conn:	Auto negotiate mode (for backward compatible)
	0 - disable ANEG, overwritten by xpcs-cl37/xpcs-cl73
	1 - enable ANEG, overwritten by xpcs-cl37/xpcs-cl73
power-save:	Tx current boost level on lane of the PHY
	0 - Default Value
	1 - 0xB

Optional properties:
- xpcs-no-phy-rx-auto-adapt: boolean,Tunes the phy hw
	parameters for current configuration.
 
xpcs_mode_cfg_seq:  management of link dynamically,
			represented by an array with each value corresponding
			to a particular speed supported options are
		0 - 10GbE-KR(default)
		1 - 10GbE-XAUI
		2 - 1GbE-SGMII (1000BaseX)
		3 - 2.5GbE-SGMII (2500BaseX)

link_poll_interval: polling period of XPCS get link status.

The following optional Channel Equalization properties are
represented by an array with each value corresponding to a
particular speed. The first array value represents the setting
for the 10GbE KR speed, the second value for the 10GbE XAUI, the second
value for the 2.5GbE speed and the fouth value for the 10GbE speed.
All four values are required if the property is used.

/* xpcs RX EQ Settings */
-xpcs-afe_en: Rx Adaptation AFE Enable on lane
-xpcs-dfe_en: Rx Decision Feedback Equalization (DFE) Enable on lane
-xpcs-cont_adapt_en: Receiver Adaptation Continuous Operation on lane
-xpcs-rx_attn_lvl: Rx Equalization Attenuation level for lane
-xpcs-rx_ctle_boost: Rx Equalization CTLE Boost value on lane
-xpcs-rx_ctle_pole: Rx Equalization CTLE Pole Value on lane
-xpcs-rx_vga2_gain:Rx Equalization VGA2 Gain on lane
-xpcs-rx_vga1_gain: Rx Equalization VGA1 Gain on lane

/* xpcs TX EQ Settings */
-xpcs-tx_eq_pre: Tx Pre-Emphasis level adjustment Control
-xpcs-tx_eq_post: Tx Post-Emphasis level adjustment Control
-xpcs-tx_eq_main: Control for setting Tx driver output amplitude
-xpcs-tx_iboost_lvl: Tx current boost level on lane
-xpcs-tx_vboost_lvl: Tx Voltage Boost Maximum Level
-xpcs-tx_vboost_en: Tx voltage Boost Enable on lane 

Example:
	wan_xpcs: wan_xpcs@18C42000 {
		compatible = "intel,xpcs";
		reg =<0x18C42000 0x400 >;
		reg-names = "xpcs_reg";
		interrupt-parent = <&gic>;
		interrupts = <GIC_SHARED 26 IRQ_TYPE_LEVEL_HIGH>;
		interrupt-names = "xpcs_irq";
		phys = <&wan_xpcs_phy>;
		phy-names = "phy";
		resets = <&rcu0 0x10 16>;
		reset-names = "xpcs_reset";
		xpcs-name = "wan_xpcs";
		xpcs-mode = <2>;
		xpcs-cl73 = <0>;
		xpcs-cl37 = <1>;
		power-save = <1>;
		xpcs-no-phy-rx-auto-adapt
		/* xpcs RX EQ Settings */
		xpcs-afe_en = <0x0>, <0x0>, <0x0>, <0x0>;
		xpcs-dfe_en = <0x0>, <0x0>, <0x0>, <0x0>;
		xpcs-cont_adapt_en = <0x0>, <0x0>, <0x0>, <0x0>;
		xpcs-rx_attn_lvl = <0x7>, <0x7>, <0x7>, <0x7>;
		xpcs-rx_ctle_boost = <0x0>, <0x0>, <0x0>, <0x0>;
		xpcs-rx_ctle_pole = <0x6>, <0x6>, <0x6>, <0x6>;
		xpcs-rx_vga2_gain = <0x5>, <0x5>, <0x5>, <0x5>;
		xpcs-rx_vga1_gain = <0x5>, <0x5>, <0x5>, <0x5>;
		/* xpcs TX EQ Settings */
		xpcs-tx_eq_pre = <0x5>, <0x5>, <0x0>, <0x0>;
		xpcs-tx_eq_post =  <0x14>, <0x14>, <0x1>, <0x1>;
		xpcs-tx_eq_main = <0x18>, <0x18>, <0xC>, <0xC>;
		xpcs-tx_iboost_lvl = <0xF>, <0xF>,<0xF>, <0xF>;
		xpcs-tx_vboost_lvl = <0x5>, <0x5>, <0x5>, <0x5>;
		xpcs-tx_vboost_en = <0x1>, <0x1>, <0x1>, <0x1>;
	}