From 9c3f3410f5ace868c7c82fe4479fd36bed5eee64 Mon Sep 17 00:00:00 2001 From: Trent Piepho Date: Wed, 22 May 2019 18:43:19 +0000 Subject: [PATCH] dt-bindings: phy: dp83867: Describe how driver behaves w.r.t rgmii delay Add a note to make it more clear how the driver behaves when "rgmii" vs "rgmii-id", "rgmii-idrx", or "rgmii-idtx" interface modes are selected. Cc: Rob Herring Cc: Mark Rutland Signed-off-by: Trent Piepho Reviewed-by: Andrew Lunn Signed-off-by: David S. Miller --- Documentation/devicetree/bindings/net/ti,dp83867.txt | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/Documentation/devicetree/bindings/net/ti,dp83867.txt b/Documentation/devicetree/bindings/net/ti,dp83867.txt index 9ef9338..99b8681 100644 --- a/Documentation/devicetree/bindings/net/ti,dp83867.txt +++ b/Documentation/devicetree/bindings/net/ti,dp83867.txt @@ -11,6 +11,14 @@ Required properties: - 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 -- 2.7.4