dt-bindings: net: Add Loongson-1 Ethernet Controller

Add devicetree binding document for Loongson-1 Ethernet controller.
And modify MAINTAINERS to add a new F: entry for
Loongson1 dt-binding documents.

Signed-off-by: Keguang Zhang <[e-mail]>
Reviewed-by: Krzysztof Kozlowski <[e-mail]>
Reviewed-by: Serge Semin <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

Documentation/devicetree/bindings/net/loongson,ls1b-gmac.yaml

···
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/net/loongson,ls1b-gmac.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Loongson-1B Gigabit Ethernet MAC Controller
+
+maintainers:
+  - Keguang Zhang <[e-mail]>
+
+description: |
+  Loongson-1B Gigabit Ethernet MAC Controller is based on
+  Synopsys DesignWare MAC (version 3.50a).
+
+  Main features
+  - Dual 10/100/1000Mbps GMAC controllers
+  - Full-duplex operation (IEEE 802.3x flow control automatic transmission)
+  - Half-duplex operation (CSMA/CD Protocol and back-pressure support)
+  - RX Checksum Offload
+  - TX Checksum insertion
+  - MII interface
+  - RGMII interface
+
+select:
+  properties:
+    compatible:
+      contains:
+        enum:
+          - loongson,ls1b-gmac
+  required:
+    - compatible
+
+properties:
+  compatible:
+    items:
+      - enum:
+          - loongson,ls1b-gmac
+      - const: snps,dwmac-3.50a
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+  clock-names:
+    items:
+      - const: stmmaceth
+
+  interrupts:
+    maxItems: 1
+
+  interrupt-names:
+    items:
+      - const: macirq
+
+  loongson,ls1-syscon:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description:
+      Phandle to the syscon containing some extra configurations
+      including PHY interface mode.
+
+  phy-mode:
+    enum:
+      - mii
+      - rgmii-id
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - clock-names
+  - interrupts
+  - interrupt-names
+  - loongson,ls1-syscon
+
+allOf:
+  - $ref: snps,dwmac.yaml#
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/loongson,ls1x-clk.h>
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    gmac0: ethernet@1fe10000 {
+        compatible = "loongson,ls1b-gmac", "snps,dwmac-3.50a";
+        reg = <0x1fe10000 0x10000>;
+
+        clocks = <&clkc LS1X_CLKID_AHB>;
+        clock-names = "stmmaceth";
+
+        interrupt-parent = <&intc1>;
+        interrupts = <2 IRQ_TYPE_LEVEL_HIGH>;
+        interrupt-names = "macirq";
+
+        loongson,ls1-syscon = <&syscon>;
+
+        phy-handle = <&phy0>;
+        phy-mode = "mii";
+        snps,pbl = <1>;
+
+        mdio {
+            #address-cells = <1>;
+            #size-cells = <0>;
+            compatible = "snps,dwmac-mdio";
+
+            phy0: ethernet-phy@0 {
+                reg = <0x0>;
+            };
+        };
+    };

Documentation/devicetree/bindings/net/loongson,ls1c-emac.yaml

···
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/net/loongson,ls1c-emac.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Loongson-1C Ethernet MAC Controller
+
+maintainers:
+  - Keguang Zhang <[e-mail]>
+
+description: |
+  Loongson-1C Ethernet MAC Controller is based on
+  Synopsys DesignWare MAC (version 3.50a).
+
+  Main features
+  - 10/100Mbps
+  - Full-duplex operation (IEEE 802.3x flow control automatic transmission)
+  - Half-duplex operation (CSMA/CD Protocol and back-pressure support)
+  - IEEE 802.1Q VLAN tag detection for reception frames
+  - MII interface
+  - RMII interface
+
+select:
+  properties:
+    compatible:
+      contains:
+        enum:
+          - loongson,ls1c-emac
+  required:
+    - compatible
+
+properties:
+  compatible:
+    items:
+      - enum:
+          - loongson,ls1c-emac
+      - const: snps,dwmac-3.50a
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+  clock-names:
+    items:
+      - const: stmmaceth
+
+  interrupts:
+    maxItems: 1
+
+  interrupt-names:
+    items:
+      - const: macirq
+
+  loongson,ls1-syscon:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description:
+      Phandle to the syscon containing some extra configurations
+      including PHY interface mode.
+
+  phy-mode:
+    enum:
+      - mii
+      - rmii
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - clock-names
+  - interrupts
+  - interrupt-names
+  - loongson,ls1-syscon
+
+allOf:
+  - $ref: snps,dwmac.yaml#
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/loongson,ls1x-clk.h>
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    emac: ethernet@1fe10000 {
+        compatible = "loongson,ls1c-emac", "snps,dwmac-3.50a";
+        reg = <0x1fe10000 0x10000>;
+
+        clocks = <&clkc LS1X_CLKID_AHB>;
+        clock-names = "stmmaceth";
+
+        interrupt-parent = <&intc1>;
+        interrupts = <2 IRQ_TYPE_LEVEL_HIGH>;
+        interrupt-names = "macirq";
+
+        loongson,ls1-syscon = <&syscon>;
+
+        phy-handle = <&phy0>;
+        phy-mode = "mii";
+        snps,pbl = <1>;
+
+        mdio {
+            #address-cells = <1>;
+            #size-cells = <0>;
+            compatible = "snps,dwmac-mdio";
+
+            phy0: ethernet-phy@13 {
+                reg = <0x13>;
+            };
+        };
+    };

MAINTAINERS

···
 M:	Keguang Zhang <[e-mail]>
 L:	[e-mail]
 S:	Maintained
+F:	Documentation/devicetree/bindings/*/loongson,ls1*.yaml
 F:	arch/mips/include/asm/mach-loongson32/
 F:	arch/mips/loongson32/
 F:	drivers/*/*loongson1*