brcm,bca-phy network driver Device Tree Bindings

PHY nodes
=========

PHY node must be a child device of a simple-bus (i.e MDIO), which has the required 'bus-type'
property, refering to bus_type_t bus name.
Each PHY driver might specify its own required and optional properties in addition to the properties
below detailed in it own binding txt file.

Required properties:

- reg:        The ID number for the phy, usually a small integer

- phy-type:   string, phydrv phy_type_t device driver type


Optional Properties:

- enet-phy-lane-swap: swap pair

- caps-no-hdx: Disable half duplex capability advertisement

- caps-no-5000: Disable 5G capability advertisement

- idle-stuffing:

- phy-reset:    gpio, if set, used to take phy out of reset before PHY initialization

- serdes-core:  serdes core index

- serdes-lane:  serdes lane index within core

- phy-external: bool, indicates phy is external to chip.

- phy-extswitch: bool, indicates external switch is connected.

- wake-on-lan: bool, indicates wake-on-lan is supported.

# TODO: is this LPORT_SERDES specific ?
- serdes-tx-disable: The GPIO phandle and specifier for the SFP tx disable signal.


egphy
=====

Represents the QGPHY block

Required properties:
- reg:          memory map for egphy registers

Optional Properties:
- base-addr:    base address of the 4 GPHY ports. default is 1 if not set.


lport
=====

Represents the LPORT block

Required properties:
- reg:          memory maps for lport registers

Optional Properties:
- base-addr:    base address of the 4 GPHY ports. default is 1 if not set.


crossbar
========

Devices like 63138, 63148, 4902, 63158, 47622 contain crossbar so N ports can shared M PHY connections.
On port side (internal endpoint), a crossbar group (PHY node) is defined.
On PHY side (external endpoint), a PHY node is also defined.

Required properties for crossbar group:
- phy-handle:   phandle to PHYs on external endpoint, can be one or more per crossbar group.

- reg:          index, indicates internal endpoint (based 0)

- phy-type:     "crossbar"


Required properties for external endpoint PHY node:
- xbar-ext-ep:  index, indicates external endpoint (based 0)

- phy-mode:     string, operation mode of the PHY interface from phy_mii_type_t.


For external endpoint PHY node with phy-mode set to "rgmii" on devices using RGMII pad control (63138, 63148, 63158) 
following optional properties should be set.

- rx-delay:   string, RGMII interface rx delay configuration.

- tx-delay:   string, RGMII interface tx delay configuration.

- rgmii-1p8v: string, RGMII interface is 1.8v 

- rgmii-3p3v: string, RGMII interface is 3.3v

- rgmii-disabled: string, RGMII interface is not connected

- rgmii-intf: index, indicates which RGMII interface (if absent, index is 0)