Merge branch 'add-support-for-open-alliance-10base-t1x-macphy-serial-interface'

Parthiban Veerasooran says:

====================
Add support for OPEN Alliance 10BASE-T1x MACPHY Serial Interface

This patch series contain the below updates,

- Adds support for OPEN Alliance 10BASE-T1x MACPHY Serial Interface
  in the net/ethernet/oa_tc6.c.

  Link to the spec:
  -----------------
  https://opensig.org/download/document/OPEN_Alliance_10BASET1x_MAC-PHY_Serial_Interface_V1.1.pdf

- Adds driver support for Microchip LAN8650/1 Rev.B1 10BASE-T1S MACPHY
  Ethernet driver in the net/ethernet/microchip/lan865x/lan865x.c.

  Link to the product:
  --------------------
  https://www.microchip.com/en-us/product/lan8650

Testing Details:
----------------
The driver performance was tested using iperf3 in the below two setups
separately.

Setup 1:
--------
Node 0 - Raspberry Pi 4 with LAN8650 MAC-PHY
Node 1 - Raspberry Pi 4 with EVB-LAN8670-USB USB Stick

Setup 2:
--------
Node 0 - SAMA7G54-EK with LAN8650 MAC-PHY
Node 1 - Raspberry Pi 4 with EVB-LAN8670-USB USB Stick

Achieved maximum of 9.4 Mbps.

Some systems like Raspberry Pi 4 need performance mode enabled to get the
proper clock speed for SPI. Refer below link for more details.

raspberrypi/linux#3381 (comment)
====================

Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

Author: kuba-moo

Documentation/devicetree/bindings/net/microchip,lan8650.yaml

@@ -0,0 +1,74 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/net/microchip,lan8650.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Microchip LAN8650/1 10BASE-T1S MACPHY Ethernet Controllers
+
+maintainers:
+  - Parthiban Veerasooran <[email protected]>
+
+description:
+  The LAN8650/1 combines a Media Access Controller (MAC) and an Ethernet
+  PHY to enable 10BASE‑T1S networks. The Ethernet Media Access Controller
+  (MAC) module implements a 10 Mbps half duplex Ethernet MAC, compatible
+  with the IEEE 802.3 standard and a 10BASE-T1S physical layer transceiver
+  integrated into the LAN8650/1. The communication between the Host and
+  the MAC-PHY is specified in the OPEN Alliance 10BASE-T1x MACPHY Serial
+  Interface (TC6).
+
+allOf:
+  - $ref: /schemas/net/ethernet-controller.yaml#
+  - $ref: /schemas/spi/spi-peripheral-props.yaml#
+
+properties:
+  compatible:
+    oneOf:
+      - const: microchip,lan8650
+      - items:
+          - const: microchip,lan8651
+          - const: microchip,lan8650
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    description:
+      Interrupt from MAC-PHY asserted in the event of Receive Chunks
+      Available, Transmit Chunk Credits Available and Extended Status
+      Event.
+    maxItems: 1
+
+  spi-max-frequency:
+    minimum: 15000000
+    maximum: 25000000
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - spi-max-frequency
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/irq.h>
+    #include <dt-bindings/gpio/gpio.h>
+
+    spi {
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      ethernet@0 {
+        compatible = "microchip,lan8651", "microchip,lan8650";
+        reg = <0>;
+        pinctrl-names = "default";
+        pinctrl-0 = <&eth0_pins>;
+        interrupt-parent = <&gpio>;
+        interrupts = <6 IRQ_TYPE_EDGE_FALLING>;
+        local-mac-address = [04 05 06 01 02 03];
+        spi-max-frequency = <15000000>;
+      };
+    };

Documentation/networking/index.rst

@@ -88,6 +88,7 @@ Contents:
    nexthop-group-resilient
    nf_conntrack-sysctl
    nf_flowtable
+   oa-tc6-framework
    openvswitch
    operstates
    packet_mmap