Subject: Re: [PATCH V6 net-next 08/11] dt-bindings: ptp: Introduce MII time stamping devices.

From: Rob Herring <[email-masked]>
Date: Wed, 18 Dec 2019 14:02:24 -0600

On Mon, Dec 16, 2019 at 08:13:23AM -0800, Richard Cochran wrote:
> This patch add a new binding that allows non-PHY MII time stamping
> devices to find their buses.  The new documentation covers both the
> generic binding and one upcoming user.
> 
> Signed-off-by: Richard Cochran <[email-masked]>
> Reviewed-by: Andrew Lunn <[email-masked]>
> ---
>  .../devicetree/bindings/ptp/ptp-ines.txt      | 35 ++++++++++++++++
>  .../devicetree/bindings/ptp/timestamper.txt   | 41 +++++++++++++++++++
>  2 files changed, 76 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/ptp/ptp-ines.txt
>  create mode 100644 Documentation/devicetree/bindings/ptp/timestamper.txt
> 
> diff --git a/Documentation/devicetree/bindings/ptp/ptp-ines.txt b/Documentation/devicetree/bindings/ptp/ptp-ines.txt
> new file mode 100644
> index 000000000000..4c242bd1ce9c
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/ptp/ptp-ines.txt
> @@ -0,0 +1,35 @@
> +ZHAW InES PTP time stamping IP core
> +
> +The IP core needs two different kinds of nodes.  The control node
> +lives somewhere in the memory map and specifies the address of the
> +control registers.  There can be up to three port handles placed as
> +attributes of PHY nodes.  These associate a particular MII bus with a
> +port index within the IP core.
> +
> +Required properties of the control node:
> +
> +- compatible:		"ines,ptp-ctrl"
> +- reg:			physical address and size of the register bank
> +
> +Required format of the port handle within the PHY node:
> +
> +- timestamper:		provides control node reference and
> +			the port channel within the IP core
> +
> +Example:
> +
> +	tstamper: timestamper@60000000 {
> +		compatible = "ines,ptp-ctrl";
> +		reg = <0x60000000 0x80>;
> +	};
> +
> +	ethernet@80000000 {
> +		...
> +		mdio {
> +			...
> +			ethernet-phy@3 {
> +				...
> +				timestamper = <&tstamper 0>;
> +			};
> +		};
> +	};
> diff --git a/Documentation/devicetree/bindings/ptp/timestamper.txt b/Documentation/devicetree/bindings/ptp/timestamper.txt
> new file mode 100644
> index 000000000000..70d636350582
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/ptp/timestamper.txt
> @@ -0,0 +1,41 @@
> +Time stamps from MII bus snooping devices
> +
> +This binding supports non-PHY devices that snoop the MII bus and
> +provide time stamps.  In contrast to PHY time stamping drivers (which
> +can simply attach their interface directly to the PHY instance), stand
> +alone MII time stamping drivers use this binding to specify the
> +connection between the snooping device and a given network interface.
> +
> +Non-PHY MII time stamping drivers typically talk to the control
> +interface over another bus like I2C, SPI, UART, or via a memory mapped
> +peripheral.  This controller device is associated with one or more
> +time stamping channels, each of which snoops on a MII bus.
> +
> +The "timestamper" property lives in a phy node and links a time
> +stamping channel from the controller device to that phy's MII bus.
> +
> +Example:
> +
> +	tstamper: timestamper@10000000 {

unit-address needs a reg property.

> +		compatible = "ines,ts-ctrl";

Should be ines,ptp-ctrl?

> +	};
> +
> +	ethernet@20000000 {
> +		mdio {
> +			ethernet-phy@1 {
> +				timestamper = <&tstamper 0>;
> +			};
> +		};
> +	};
> +
> +	ethernet@30000000 {
> +		mdio {
> +			ethernet-phy@2 {
> +				timestamper = <&tstamper 1>;
> +			};
> +		};
> +	};
> +
> +In this example, time stamps from the MII bus attached to phy@1 will
> +appear on time stamp channel 0 (zero), and those from phy@2 appear on
> +channel 1.
> -- 
> 2.20.1
>