dt-bindings: PCI: Add MT7621 SoC PCIe host controller

Add device tree binding documentation for PCIe in MT7621 SoCs.

Link: https://lore.kernel.org/r/20210922050035.18162-2-sergio.paracuellos@gmail.comSigned-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rob Herring <robh@kernel.org>

Documentation/devicetree/bindings/pci/mediatek,mt7621-pcie.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/pci/mediatek,mt7621-pcie.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: MediaTek MT7621 PCIe controller
+
+maintainers:
+  - Sergio Paracuellos <sergio.paracuellos@gmail.com>
+
+description: |+
+  MediaTek MT7621 PCIe subsys supports a single Root Complex (RC)
+  with 3 Root Ports. Each Root Port supports a Gen1 1-lane Link
+
+allOf:
+  - $ref: /schemas/pci/pci-bus.yaml#
+
+properties:
+  compatible:
+    const: mediatek,mt7621-pci
+
+  reg:
+    items:
+      - description: host-pci bridge registers
+      - description: pcie port 0 RC control registers
+      - description: pcie port 1 RC control registers
+      - description: pcie port 2 RC control registers
+
+  ranges:
+    maxItems: 2
+
+patternProperties:
+  'pcie@[0-2],0':
+    type: object
+    $ref: /schemas/pci/pci-bus.yaml#
+
+    properties:
+      resets:
+        maxItems: 1
+
+      clocks:
+        maxItems: 1
+
+      phys:
+        maxItems: 1
+
+    required:
+      - "#interrupt-cells"
+      - interrupt-map-mask
+      - interrupt-map
+      - resets
+      - clocks
+      - phys
+      - phy-names
+      - ranges
+
+    unevaluatedProperties: false
+
+required:
+  - compatible
+  - reg
+  - ranges
+  - "#interrupt-cells"
+  - interrupt-map-mask
+  - interrupt-map
+  - reset-gpios
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    #include <dt-bindings/interrupt-controller/mips-gic.h>
+
+    pcie: pcie@1e140000 {
+        compatible = "mediatek,mt7621-pci";
+        reg = <0x1e140000 0x100>,
+              <0x1e142000 0x100>,
+              <0x1e143000 0x100>,
+              <0x1e144000 0x100>;
+
+        #address-cells = <3>;
+        #size-cells = <2>;
+        pinctrl-names = "default";
+        pinctrl-0 = <&pcie_pins>;
+        device_type = "pci";
+        ranges = <0x02000000 0 0x60000000 0x60000000 0 0x10000000>,  /* pci memory */
+                 <0x01000000 0 0x1e160000 0x1e160000 0 0x00010000>;  /* io space */
+        #interrupt-cells = <1>;
+        interrupt-map-mask = <0xF800 0 0 0>;
+        interrupt-map = <0x0000 0 0 0 &gic GIC_SHARED 4 IRQ_TYPE_LEVEL_HIGH>,
+                        <0x0800 0 0 0 &gic GIC_SHARED 24 IRQ_TYPE_LEVEL_HIGH>,
+                        <0x1000 0 0 0 &gic GIC_SHARED 25 IRQ_TYPE_LEVEL_HIGH>;
+        reset-gpios = <&gpio 19 GPIO_ACTIVE_LOW>;
+
+        pcie@0,0 {
+            reg = <0x0000 0 0 0 0>;
+            #address-cells = <3>;
+            #size-cells = <2>;
+            device_type = "pci";
+            #interrupt-cells = <1>;
+            interrupt-map-mask = <0 0 0 0>;
+            interrupt-map = <0 0 0 0 &gic GIC_SHARED 4 IRQ_TYPE_LEVEL_HIGH>;
+            resets = <&rstctrl 24>;
+            clocks = <&clkctrl 24>;
+            phys = <&pcie0_phy 1>;
+            phy-names = "pcie-phy0";
+            ranges;
+        };
+
+        pcie@1,0 {
+            reg = <0x0800 0 0 0 0>;
+            #address-cells = <3>;
+            #size-cells = <2>;
+            device_type = "pci";
+            #interrupt-cells = <1>;
+            interrupt-map-mask = <0 0 0 0>;
+            interrupt-map = <0 0 0 0 &gic GIC_SHARED 24 IRQ_TYPE_LEVEL_HIGH>;
+            resets = <&rstctrl 25>;
+            clocks = <&clkctrl 25>;
+            phys = <&pcie0_phy 1>;
+            phy-names = "pcie-phy1";
+            ranges;
+        };
+
+        pcie@2,0 {
+            reg = <0x1000 0 0 0 0>;
+            #address-cells = <3>;
+            #size-cells = <2>;
+            device_type = "pci";
+            #interrupt-cells = <1>;
+            interrupt-map-mask = <0 0 0 0>;
+            interrupt-map = <0 0 0 0 &gic GIC_SHARED 25 IRQ_TYPE_LEVEL_HIGH>;
+            resets = <&rstctrl 26>;
+            clocks = <&clkctrl 26>;
+            phys = <&pcie2_phy 0>;
+            phy-names = "pcie-phy2";
+            ranges;
+        };
+    };
+...