[v2,0/7] ravb: Add support for explicit internal clock delay configuration

Hi all,

Some Renesas EtherAVB variants support internal clock delay
configuration, which can add larger delays than the delays that are
typically supported by the PHY (using an "rgmii-*id" PHY mode, and/or
"[rt]xc-skew-ps" properties).

Historically, the EtherAVB driver configured these delays based on the
"rgmii-*id" PHY mode.  This caused issues with PHY drivers that
implement PHY internal delays properly[1].  Hence a backwards-compatible
workaround was added by masking the PHY mode[2].

This patch series implements the next step of the plan outlined in [3],
and adds proper support for explicit configuration of the MAC internal
clock delays using new "[rt]x-internal-delay-ps" properties.  If none of
these properties is present, the driver falls back to the old handling.

This can be considered the MAC counterpart of commit 9150069bf5fc0e86
("dt-bindings: net: Add tx and rx internal delays"), which applies to
the PHY.  Note that unlike commit 92252eec913b2dd5 ("net: phy: Add a
helper to return the index for of the internal delay"), no helpers are
provided to parse the DT properties, as so far there is a single user
only, which supports only zero or a single fixed value.  Of course such
helpers can be added later, when the need arises, or when deemed useful
otherwise.

This series consists of 4 parts:
  1. DT binding updates documenting the new properties, for both the
     generic ethernet-controller and the EtherAVB-specific bindings.
     => intended to be merged through net-next.
  2. EtherAVB driver update implementing support for the new properties.
     => intended to be merged through net-next.
  3. DT updates, one for R-Car Gen3 and RZ/G2 SoC families each.
     => intended to be merged through renesas-devel and arm-soc, but
	only _after_ 2. has hit upstream.
  4. Conversion to json-schema of the Renesas EtherAVB DT bindings.
     Technically, the conversion is independent of all of the above.
     I included it in this series, as it shows how all sanity checks on
     "[rt]x-internal-delay-ps" values are implemented as DT binding
     checks.
     => intended to be merged through net-next, or devicetree (ignoring
        any conflict due to 1.).

Changes compared to v1[4] (more detail in the individual patch
descriptions):
  - Added "[PATCH 1/7] dt-bindings: net: ethernet-controller: Add
    internal delay properties",
  - Replace "renesas,[rt]xc-delay-ps" by "[rt]x-internal-delay-ps",
  - Incorporated EtherAVB DT binding conversion to json-schema.
  - Add Reviewed-by,

Impacted, tested:
  - Salvator-X(S) with R-Car H3 ES1.0 and ES2.0, M3-W, and M3-N.

Not impacted, tested:
  - Ebisu with R-Car E3.

Impacted, not tested:
  - Salvator-X(S) with other SoC variants,
  - ULCB with R-Car H3/M3-W/M3-N variants,
  - V3MSK and Eagle with R-Car V3M,
  - Draak with R-Car V3H,
  - HiHope RZ/G2[MN] with RZ/G2M or RZ/G2N.

To ease testing, I have pushed this series to the
topic/ravb-internal-clock-delays-v2 branch of my renesas-drivers
repository at
git://git.kernel.org/pub/scm/linux/kernel/git/geert/renesas-drivers.git.

Thanks for your comments!

References:
  [1] Commit bcf3440c6dd78bfe ("net: phy: micrel: add phy-mode support
      for the KSZ9031 PHY")
  [2] Commit 9b23203c32ee02cd ("ravb: Mask PHY mode to avoid inserting
      delays twice").
      https://lore.kernel.org/r/20200529122540.31368-1-geert+renesas@glider.be/
  [3] https://lore.kernel.org/r/CAMuHMdU+MR-2tr3-pH55G0GqPG9HwH3XUd=8HZxprFDMGQeWUw@mail.gmail.com/
  [4] https://lore.kernel.org/linux-devicetree/20200619191554.24942-1-geert+renesas@glider.be/

Geert Uytterhoeven (7):
  dt-bindings: net: ethernet-controller: Add internal delay properties
  dt-bindings: net: renesas,ravb: Document internal clock delay
    properties
  ravb: Split delay handling in parsing and applying
  ravb: Add support for explicit internal clock delay configuration
  arm64: dts: renesas: rcar-gen3: Convert EtherAVB to explicit delay
    handling
  arm64: dts: renesas: rzg2: Convert EtherAVB to explicit delay handling
  dt-bindings: net: renesas,etheravb: Convert to json-schema

 .../bindings/net/ethernet-controller.yaml     |  14 +
 .../bindings/net/renesas,etheravb.yaml        | 261 ++++++++++++++++++
 .../devicetree/bindings/net/renesas,ravb.txt  | 134 ---------
 .../boot/dts/renesas/hihope-rzg2-ex.dtsi      |   2 +-
 arch/arm64/boot/dts/renesas/r8a774a1.dtsi     |   2 +
 arch/arm64/boot/dts/renesas/r8a774b1.dtsi     |   2 +
 arch/arm64/boot/dts/renesas/r8a774c0.dtsi     |   1 +
 arch/arm64/boot/dts/renesas/r8a77951.dtsi     |   2 +
 arch/arm64/boot/dts/renesas/r8a77960.dtsi     |   2 +
 arch/arm64/boot/dts/renesas/r8a77961.dtsi     |   2 +
 arch/arm64/boot/dts/renesas/r8a77965.dtsi     |   2 +
 .../arm64/boot/dts/renesas/r8a77970-eagle.dts |   3 +-
 .../arm64/boot/dts/renesas/r8a77970-v3msk.dts |   3 +-
 arch/arm64/boot/dts/renesas/r8a77970.dtsi     |   2 +
 arch/arm64/boot/dts/renesas/r8a77980.dtsi     |   2 +
 arch/arm64/boot/dts/renesas/r8a77990.dtsi     |   1 +
 arch/arm64/boot/dts/renesas/r8a77995.dtsi     |   1 +
 .../boot/dts/renesas/salvator-common.dtsi     |   2 +-
 arch/arm64/boot/dts/renesas/ulcb.dtsi         |   2 +-
 drivers/net/ethernet/renesas/ravb.h           |   5 +-
 drivers/net/ethernet/renesas/ravb_main.c      |  53 +++-
 21 files changed, 346 insertions(+), 152 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/net/renesas,etheravb.yaml
 delete mode 100644 Documentation/devicetree/bindings/net/renesas,ravb.txt