linux_dsm_epyc7002/Documentation/devicetree/bindings/net/ti,dp83867.txt
Trent Piepho 980066e6d9 dt-bindings: phy: dp83867: Add documentation for disabling clock output
The clock output is generally only used for testing and development and
not used to daisy-chain PHYs.  It's just a source of RF noise afterward.

Add a mux value for "off".  I've added it as another enumeration to the
output property.  In the actual PHY, the mux and the output enable are
independently controllable.  However, it doesn't seem useful to be able
to describe the mux setting when the output is disabled.

Document that PHY's default setting will be left as is if the property
is omitted.

Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Trent Piepho <tpiepho@impinj.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-22 17:40:17 -07:00

59 lines
2.6 KiB
Plaintext

* Texas Instruments - dp83867 Giga bit ethernet phy
Required properties:
- reg - The ID number for the phy, usually a small integer
- ti,rx-internal-delay - RGMII Receive Clock Delay - see dt-bindings/net/ti-dp83867.h
for applicable values. Required only if interface type is
PHY_INTERFACE_MODE_RGMII_ID or PHY_INTERFACE_MODE_RGMII_RXID
- ti,tx-internal-delay - RGMII Transmit Clock Delay - see dt-bindings/net/ti-dp83867.h
for applicable values. Required only if interface type is
PHY_INTERFACE_MODE_RGMII_ID or PHY_INTERFACE_MODE_RGMII_TXID
- ti,fifo-depth - Transmitt FIFO depth- see dt-bindings/net/ti-dp83867.h
for applicable values
Note: If the interface type is PHY_INTERFACE_MODE_RGMII the TX/RX clock delays
will be left at their default values, as set by the PHY's pin strapping.
The default strapping will use a delay of 2.00 ns. Thus
PHY_INTERFACE_MODE_RGMII, by default, does not behave as RGMII with no
internal delay, but as PHY_INTERFACE_MODE_RGMII_ID. The device tree
should use "rgmii-id" if internal delays are desired as this may be
changed in future to cause "rgmii" mode to disable delays.
Optional property:
- ti,min-output-impedance - MAC Interface Impedance control to set
the programmable output impedance to
minimum value (35 ohms).
- ti,max-output-impedance - MAC Interface Impedance control to set
the programmable output impedance to
maximum value (70 ohms).
- ti,dp83867-rxctrl-strap-quirk - This denotes the fact that the
board has RX_DV/RX_CTRL pin strapped in
mode 1 or 2. To ensure PHY operation,
there are specific actions that
software needs to take when this pin is
strapped in these modes. See data manual
for details.
- ti,clk-output-sel - Muxing option for CLK_OUT pin. See dt-bindings/net/ti-dp83867.h
for applicable values. The CLK_OUT pin can also
be disabled by this property. When omitted, the
PHY's default will be left as is.
Note: ti,min-output-impedance and ti,max-output-impedance are mutually
exclusive. When both properties are present ti,max-output-impedance
takes precedence.
Default child nodes are standard Ethernet PHY device
nodes as described in Documentation/devicetree/bindings/net/phy.txt
Example:
ethernet-phy@0 {
reg = <0>;
ti,rx-internal-delay = <DP83867_RGMIIDCTL_2_25_NS>;
ti,tx-internal-delay = <DP83867_RGMIIDCTL_2_75_NS>;
ti,fifo-depth = <DP83867_PHYCR_FIFO_DEPTH_4_B_NIB>;
};
Datasheet can be found:
http://www.ti.com/product/DP83867IR/datasheet